Jhuma Sadhukhan

Dr Jhuma Sadhukhan


Reader

Academic and research departments

Centre for Environment and Sustainability.

Biography

Biography

Jhuma Sadhukhan is a Fellow of the Institution of Chemical Engineers (FIChemE), Chartered Engineer (CEng) and Chartered Scientist (CSci). With extensive industrial and academic experience with Technip, MW Kellogg Ltd., The University of Manchester, Imperial College London (Visiting Academic) and University of Surrey, she brings unique expertise in sustainability and engineering systems. She has published widely in the area and received several internationally acclaimed awards, the IChemE Moulton Medal 2010 and Hanson medal 2006 and First prize at the IChemE International Conference on 'Gasification for the Future', The Netherlands, 10-14 April 2000. She and her colleagues at Nottingham Malaysia have been a Finalist in the WBM Bio Business Award 2015. She regularly gives keynote speeches at international conferences.

Research interests

Jhuma Sadhukhan, Founder of IBEST (Institution of Biorefinery Engineers, Scientists and Technologists), undertakes fundamental research in “Biorefinery” and “Resource Recovery from Waste”. She does modelling, simulation and design, across the scale, from molecules to systems, and techno-economic analysis, life cycle assessment, life cycle costing and life cycle sustainability assessment.

She is the Sustainability theme leader of multi-disciplinary Consortia: METEORR Consortium of the NERC “Resource Recovery from Waste” programme and LifesCO2R Consortium of the EPSRC “Liquid Fuel and bioEnergy Supply from CO2 Reduction”. She is the Editor of the Elsevier and IChemE journal: Sustainable Production and Consumption and the Special Issue on Biorefinery Value Chain Creation Chemical Engineering Research and Design.

Read Editorial “Sustainable Availability and Utilisation of Wastes”. Sustainable Production and Consumption, 9, 2017, 1-2.Read Editorial “Biorefinery Value Chain Creation”. Chemical Engineering Research & Design, 107, 2016, 1-3.

Her scholastic teaching and learning leadership includes internationally acclaimed Wiley's Advanced (Authored) Textbook: Biorefineries and Chemical Processes: Design, integration and Sustainability Analysis consisting of 1150 pages, including 625 pages paperback and web material.

A few of the commendations on the book are as follows: “This book is designed as an advanced text for final year and postgraduate chemical engineers as well as for the teaching staff. It deals with the specialized subject matter thoroughly with good explanations of the chemistries involved and emphasizes where conventional chemical engineering principles differ from those needed to design biorefinery plant. Admirably, an “economic analysis” chapter is provided and includes the standard discounted cash flow method for evaluating the ongoing financial viability of any production unit.” - Springer (Chromatographia, DOI 10.1007/s10337-015-2843-9).

“This book aims to bridge the gap between engineering and sustainability in bio-based processes, with the help of analytical tools for economic and environmental assessment - and it succeeds in doing so. The reader will also learn how to apply these tools, thanks to the numerous problems elaborated and solved using software like ASPEN, MATLAB and GaBi (for LCA). In conclusion, this book introduces the reader to the rapidly-developing industry of biorefineries, with a multi-disciplinary approach. It is a good resource for undergraduate and post-graduate students who want to learn about biorefineries; it can also be valuable for researchers who are looking to practically apply these analytical tools in their work.” - Green Processing & Synthesis (Green Process Synth 2015; 4: 65-66)

“It looks so substantial (in the literal sense of containing a lots of tangible substance) and so high quality! The scope and quality of the resources, including the additional web material, are extensive, and the pedagogical innovations and presentation are creative and empowering. I believe it has the potential to be a game-changer by giving a basis for educating the biorefinery engineers who will actually bring about the power and contribution that biorefineries, correctly conceived, designed and operated, can deliver. This book is the first in this area and has done a remarkable job of synthesising process integration and sustainability approaches for application to biorefinery design and evaluation, including significantly new approaches developed by the authors. The book has been well received and promises to have a major impact in empowering the application of process integration approaches into biorefineries and in developing true biorefinery engineers who are able to exploit the power of formal process integration.” - A UK University Professor.

Her research has been funded by NERC, EPSRC, BBSRC, British Council, Royal Academy of Engineering (RAEng), Royal Society of Chemistry (RSC), European Commission, industries and overseas funding organisations.

Other research roles

  • PI of UK-India British Council / RSC Researcher Links Workshop on “Energy for Economic Development and Welfare”
  • PI of UK-Malaysia British Council / Akademi of Sains Malaysia Researcher Links Workshop on "Bioenergy, Biorefinery and Bioeconomy"
  • PI of UK-Mexico British Council / CONACYT Researcher Links Workshop on “Biorefinery Research”
  • PI of UK-Mexico RAEng Newton Collaborative Grant “Economic Value Generation and Social Welfare in Mexico by Waste Biorefining”
  • PI of NERC Grant “Life Cycle Sustainability and Policy Analyses of Plausible Systems for Resource Recovery from Waste (RRfW)”
  • PI of HEFCE Newton Fund “Biorefinery Systems for Social Welfare and Economic Development: A Focus Group Workshop on Impact Generation”
  • Winner of IChemE Junior Moulton Medal 2011 and Hanson Medal 2006 and Finalist in the WBM Bio Business Award 2015.

Research collaborations

Her PhD graduates are:

  • Freddie Pask (2016)
  • Stefanie Reiss (2016)
  • Elias Martinez-Hernandez (2013)
  • Kok Siew Ng (2011)
  • Ankur Kapil (2009)
  • Mian Xu (2009)
  • Fernan Mateos-Salvador (2010)
  • Ta-Chen Lin (2008)
  • Yuhang Lou (2008)

Her PhDs:

  • Ms Ida Md Jaye
  • Mr Eyo Ansa, DECC

Her EngDs:

  • Mr Freddie Pask, 3M
  • Mr Jamal Miah, Nestle
  • Ms Stefanie Niekamp, TWI Ltd.
  • Mr Matthew Gear, Recycling Technologies
  • Mr Rupert Zierler, Network Rail
  • Mr Alex Tooby, Unilever
  • Ms Sophie Parsons, National Physical Laboratory

Her Research Fellows:

  • Dr Kok Siew Ng
  • Dr Rex T L Ng
  • Mr Chinedu Okoli
  • Dr Mirjam Roeder
  • Dr Shrikant Bhat
  • Dr Mustafa Mustafa

Teaching

  • Convener of Life Cycle Assessment
  • Convener of Biomass Processing Technology
  • Convener of Dissertation in Centre for Environment and Sustainability
  • Coordinator and teacher of CPD courses in Process Systems Engineering, Biorefinery Systems and Sustainability Analysis
  • See EUBCE 2016 and IChemE 2016

Affiliations

  • FIChemE (Fellow of Institution of Chemical Engineers)
  • Member of ACS (American Chemical Society)
  • Member of AIChE (American Institute of Chemical Engineers)

My publications

Publications

Martinez-Hernandez E, Ibrahim M, Campbell G, Leach MA, Sinclair P, Sadhukhan J (2013) Environmental sustainability analysis of UK whole-wheat bioethanol and CHP systems, Biomass and Bioenergy 50 pp. 52-64 Elsevier
The UK whole-wheat bioethanol and straw and DDGS-based combined heat and power (CHP) generation systems were assessed for environmental sustainability using a range of impact categories or characterisations (IC): cumulative primary fossil energy (CPE), land use, life cycle global warming potential over 100 years (GWP), acidification potential (AP), eutrophication potential (EP) and abiotic resources use (ARU). The European Union (EU) Renewable Energy Directive's target of greenhouse gas (GHG) emission saving of 60% in comparison to an equivalent fossil-based system by 2020 seems to be very challenging for stand-alone wheat bioethanol system. However, the whole-wheat integrated system, wherein the CHP from the excess straw grown in the same season and from the same land is utilised in the wheat bioethanol plant, can be demonstrated for potential sustainability improvement, achieving 85% emission reduction and 97% CPE saving compared to reference fossil systems. The net bioenergy from this system and from 172,370 ha of grade 3 land is 12.1 PJ y providing land to energy yield of 70 GJ ha y. The use of DDGS as an animal feed replacing soy meal incurs environmental emission credit, whilst its use in heat or CHP generation saves CPE. The hot spots in whole system identified under each impact category are as follows: bioethanol plant and wheat cultivation for CPE (50% and 48%), as well as for ARU (46% and 52%). EP and GWP are distributed among wheat cultivation (49% and 37%), CHP plant (26% and 30%) and bioethanol plant (25%, and 33%), respectively. © 2013 Elsevier Ltd.
Martinez-Hernandez E, Campbell G, Sadhukhan J (2013) Economic value and environmental impact (EVEI) analysis of biorefinery systems, Chemical Engineering Research and Design 91 (8) pp. 1418-1426 Elsevier
The selection of product portfolios, processing routes and the combination of technologies to obtain a sustainable biorefinery design according to economic and environmental criteria represents a challenge to process engineering. The aim of this research is to generate a robust methodology that assists process engineers to conceptually optimise the environmental and economic performances of biorefinery systems. A novel economic value and environmental impact (EVEI) analysis methodology is presented in this paper. The EVEI analysis is a tool that emerges from the combination of the value analysis method for the evaluation of economic potential with environmental footprinting for impact analysis. The methodology has been effectively demonstrated by providing insights into the performance of a bioethanol plant as a case study. The systematisation of the methodology allowed its implementation and integration into a computer-aided process engineering (CAPE) tool in the spreadsheet environment. © 2013 The Institution of Chemical Engineers.
Xu M, Wilson K, Sadhukhan J (2008) Simulation process of biodiesel production over heterogeneous catalysts, ACS National Meeting Book of Abstracts
Biodiesel production is a very promising area due to the relevance that it is an environmental-friendly diesel fuel alternative to fossil fuel derived diesel fuels. Nowadays, most industrial applications of biodiesel production are performed by the transesterification of renewable biological sources based on homogeneous acid catalysts, which requires downstream neutralization and separation leading to a series of technical and environmental problems. However, heterogeneous catalyst can solve these issues, and be used as a better alternative for biodiesel production. Thus, a heuristic diffusion-reaction kinetic model has been established to simulate the transesterification of alkyl ester with methanol over a series of heterogeneous Cs-doped heteropolyacid catalysts. The novelty of this framework lies in detailed modeling of surface reacting kinetic phenomena and integrating that with particle-level transport phenomena all the way through to process design and optimisation, which has been done for biodiesel production process for the first time. This multi-disciplinary research combining chemistry, chemical engineering and process integration offers better insights into catalyst design and process intensification for the industrial application of Cs-doped heteropolyacid catalysts for biodiesel production. A case study of the transesterification of tributyrin with methanol has been demonstrated to establish the effectiveness of this methodology.
Ng KS, Sadhukhan J (2011) Techno-economic performance analysis of bio-oil based Fischer-Tropsch and CHP synthesis platform, BIOMASS & BIOENERGY 35 (7) pp. 3218-3234 Elsevier
The techno-economic potential of the UK poplar wood and imported oil palm empty fruit bunch derived bio-oil integrated gasification and Fischer-Tropsch (BOIG-FT) systems for the generation of transportation fuels and combined heat and power (CHP) was investigated. The bio-oil was represented in terms of main chemical constituents, i.e. acetic acid, acetol and guaiacol. The compositional model of bio-oil was validated based on its performance through a gasification process. Given the availability of large scale gasification and FT technologies and logistic constraints in transporting biomass in large quantities, distributed bio-oil generations using biomass pyrolysis and centralised bio-oil processing in BOIG-FT system are technically more feasible. Heat integration heuristics and composite curve analysis were employed for once-through and full conversion configurations, and for a range of economies of scale, 1 MW, 675 MW and 1350 MW LHV of bio-oil. The economic competitiveness increases with increasing scale. A cost of production of FT liquids of 78.7 Euro/MWh was obtained based on 80.12 Euro/MWh of electricity, 75 Euro/t of bio-oil and 116.3 million Euro/y of annualised capital cost.
Sadhukhan J, Smith R (2005) Synthesis of industrial system based on value analysis, Computer Aided Chemical Engineering 20 (C) pp. 793-798
In this contribution, we present a novel methodology for flexible design of industrial systems based on detailed differential value analysis (Sadhukhan, J. Ph.D. Dissertation, UMIST, Manchester, U.K., 2002). Evolving from graph theory this methodology performs better than conventional mathematical programming based optimisation approaches through systematic structural decomposition of large scale industrial systems into basic processing elements (paths and trees), which helps to reduce the size and the complexity of large combinatorial problems and comprehensively analyse the multiple objectives, set of optimal operating states and marginal contributions at elemental levels that are critical for flexible designs. © 2005 Elsevier B.V. All rights reserved.
Kapil A, Bhat SA, Sadhukhan J (2008) Multiscale characterization framework for sorption enhanced reaction processes, AICHE JOURNAL 54 (4) pp. 1025-1036 JOHN WILEY & SONS INC
Martinez-Hernandez E, Campbell GM, Sadhukhan J (2014) Economic and environmental impact marginal analysis of biorefinery products for policy targets, Journal of Cleaner Production 74 pp. 74-85
A simple biofuel production system can be first examined for its policy compliance in terms of GHG emission reduction target relative to fossil-based counterparts. More integrated and optimised biorefinery systems with polygeneration can then be evolved with the aid of graphical analysis of marginal emission savings vs. additional economic margins. This bottom-up approach helps to achieve greater GHG emission cut by integrated systems design and thereby setting a more stringent benchmark to support policies towards achieving climate change mitigation goals. The combined Economic Value and Environmental Impact analysis is a multi-level methodology that can be used to represent biorefinery system performances as an aggregate of differential economic and environmental impact margins of biorefinery products. The methodology is extended in this paper to support process integration strategies that allow achieving policy compliance of biorefinery products in terms of GHG emission savings. An economic and environmental impact profile of the products is introduced for a graphical visualisation of economic costs and values as well as deficits and surpluses in environmental impact savings. The effectiveness of the extended methodology has been demonstrated using a Jatropha-based biorefinery system converting Jatropha seed into biodiesel, glycerol and cake, as a case study. The biodiesel produced can achieve 53% emission cut, while glycerol and cake can achieve an emission cut by 57% by displacing similar functionality fossil based products. © 2014 Elsevier Ltd. All rights reserved.
Martinez-Hernandez E, Campbell G, Sadhukhan J (2013) Economic value and environmental impact (EVEI) analysis of biorefinery systems, Chemical Engineering Research and Design 91 (8) pp. 1418-1426
The selection of product portfolios, processing routes and the combination of technologies to obtain a sustainable biorefinery design according to economic and environmental criteria represents a challenge to process engineering. The aim of this research is to generate a robust methodology that assists process engineers to conceptually optimise the environmental and economic performances of biorefinery systems. A novel economic value and environmental impact (EVEI) analysis methodology is presented in this paper. The EVEI analysis is a tool that emerges from the combination of the value analysis method for the evaluation of economic potential with environmental footprinting for impact analysis. The methodology has been effectively demonstrated by providing insights into the performance of a bioethanol plant as a case study. The systematisation of the methodology allowed its implementation and integration into a computer-aided process engineering (CAPE) tool in the spreadsheet environment. © 2013 The Institution of Chemical Engineers.
Ng KS, Zhang N, Sadhukhan J (2013) Techno-economic analysis of polygeneration systems with carbon capture and storage and CO reuse, Chemical Engineering Journal 219 pp. 96-108 Elsevier
Several decarbonised polygeneration schemes exploiting carbon capture and storage (CCS) or CO reuse technologies for the generation of clean fuels, chemicals, electricity and heat have been systematically analysed for techno-economic feasibility. Process simulation, energy integration and economic analysis were undertaken to analyse the effect of process configurations and operating conditions on the economic potential (EP) and risks. CO capture and reuse producing methane using Sabatier's reaction shows less favourable economics compared to the counterpart CCS based scheme, both producing electricity, hydrogen, acetic acid and methanol in common. Post-combustion CO tri-reforming into methanol production in addition to electricity generation shows overall favourable economics compared to the counterpart integrated gasification combined cycle (IGCC) with CCS scheme. Thus, increasing product portfolio from energy products in a cogeneration plant to chemical products evolved from thermodynamic and process integration synergies increases the techno-economic viability. Bio-oil can be processed as an alternative low carbon feedstock. While bio-oil creates environmental incentives, its economic competitiveness can be enhanced by introducing credits on product prices. © 2013 Elsevier B.V.
Pask F, Sadhukhan J, Lake P, McKenna S, Perez EB, Yang A (2014) Systematic approach to industrial oven optimisation for energy saving, Applied Thermal Engineering 71 (1) pp. 72-77
Industrial ovens consume a sizable proportion of energy within the manufacturing sector. Although there has been considerable research into energy reduction of industrial processes throughout literature, there is not yet a generalised tool to reduce energy within industrial ovens. The systematic approach presented aims to guide an engineer through five stages of oven optimisation. These involve defining the scope of the optimisation project, measuring and analysing process variables in order to develop fundamental understanding of the system so that an optimisation plan can be established and then implemented. The paper gives an application example of the methodology to a curing oven within a masking tape manufacturing facility. This approach showed an estimated annual saving of 1,658,000 kWh (29% reduction of the oven's energy consumption and a 4.7% reduction of the whole plant's energy consumption) with very little capital expenditure. As the methodology can be tailored to accommodate individual optimisation options for each oven scenario, while still providing a clear pathway, it has potential applications within the wider manufacturing industry. © 2014 Elsevier Ltd. All rights reserved.
Sadhukhan J, Zhang N, Zhu XX, Smith R (2004) Value analysis of industrial systems, AIChE Annual Meeting, Conference Proceedings
A generalized strategy for modeling and integration of an overall system is developed for detailed economic analysis of industrial systems. Industrial applications of the value analysis method by Sadhukhan (2002) for such an economic analysis of complex systems, e.g., refineries, petrochemical complexes, having a number of processing networks, is carried out. The approach for economic analysis of a system is simple and provides a transparent and complete set of economic values for all basic components and correlates these values with the overall system economic margin. The approach considers all possible effects of interactions among streams and processes and retains the overall integrity in the economic analysis. At the same time rigorous process models can be used to capture the effects of real plant operations in economic analysis. Even for complex systems such as refineries with many processing networks interacting in complicated ways, such economic analysis can be conveniently carried out by integrating the overall system while retaining the quality of models at process level. This is an abstract of a paper presented at the AIChE Annual Meeting (Austin, TX 11/7-12/2004).
Sadhukhan J, Ng KS, Martinez Hernandez E (2014) Biorefineries and Chemical Processes: Design, Integration and Sustainability Analysis, pp. 1-625 Wiley
As the range of feedstocks, process technologies and products expand, biorefineries will become increasingly complex manufacturing systems. Biorefineries and Chemical Processes: Design, Integration and Sustainability Analysis presents process modelling and integration, and whole system life cycle analysis tools for the synthesis, design, operation and sustainable development of biorefinery and chemical processes.

Topics covered include:

Introduction: An introduction to the concept and development of biorefineries.

Tools: Included here are the methods for detailed economic and environmental impact analyses; combined economic value and environmental impact analysis; life cycle assessment (LCA); multi-criteria analysis; heat integration and utility system design; mathematical programming based optimization and genetic algorithms.

Process synthesis and design: Focuses on modern unit operations and innovative process flowsheets. Discusses thermochemical and biochemical processing of biomass, production of chemicals and polymers from biomass, and processes for carbon dioxide capture.

Biorefinery systems: Presents biorefinery process synthesis using whole system analysis. Discusses bio-oil and algae biorefineries, integrated fuel cells and renewables, and heterogeneous catalytic reactors.

Companion website: Four case studies, additional exercises and examples are available online, together with three supplementary chapters which address waste and emission minimization, energy storage and control systems, and the optimization and reuse of water.

This textbook is designed to bridge a gap between engineering design and sustainability assessment, for advanced students and practicing process designers and engineers.

Ng KS, Zhang N, Sadhukhan J (2012) Decarbonised coal energy system advancement through CO 2 utilisation and polygeneration, Clean Technologies and Environmental Policy 14 (3) pp. 443-451
Development of clean coal technology is highly envisaged to mitigate the CO 2 emission level whilst meeting the rising global energy demands which require highly efficient and economically compelling technology. Integrated gasification combined cycle (IGCC) with carbon capture and storage (CCS) system is highly efficient and cleaner compared to the conventional coal-fired power plant. In this study, an alternative process scheme for IGCC system has been proposed, which encompasses the reuse of CO 2 from the flue gas of gas turbine into syngas generation, followed by methanol synthesis. The thermodynamic efficiency and economic potential are evaluated and compared for these two systems. The performances of the systems have been enhanced through systematic energy integration strategies. It has been found that the thermodynamic and economic feasibilities have attained significant improvement through the realisation of a suitably balanced polygeneration scheme. The economic potential can be enhanced from negative impact to 317 M¬/y (3.6 ¬/GJ). The results have demonstrated promising prospects of employing CO 2 reuse technology into IGCC system, as an alternative to CCS system. © 2011 Springer-Verlag.
Ng KS, Zhang N, Sadhukhan J (2011) Process Synthesis with Heat Integration of Decarbonised Coal Energy Systems, PRES 2011: 14TH INTERNATIONAL CONFERENCE ON PROCESS INTEGRATION, MODELLING AND OPTIMISATION FOR ENERGY SAVING AND POLLUTION REDUCTION, PTS 1 AND 2: Chemical Enginnering Transactions 25 pp. 387-392
Development of clean coal technology is highly envisaged to mitigate the CO2 emission
level while meeting the rising global energy demands which require highly efficient and
economically compelling technology. Integrated gasification combined cycle (IGCC)
with carbon capture and storage (CCS) system is highly efficient and cleaner compared
to the conventional coal-fired power plant. In this study, an alternative process scheme
for IGCC system has been proposed, which encompasses the recycling and re-use of
CO2 from the flue gas of gas turbine into a secondary syngas processing route,
proceeding with conversion of syngas into methanol. The system modification requires
extensive mass and energy integration strategies to ensure that the efficiency and
economics of the system are achieved to a considerably high level. The thermodynamic
and economic feasibilities of the modified IGCC system were found to attain
tremendous improvements. The thermal efficiency has been increased from 54% to
89.3%, whilst the economic potential has been enhanced from 48.1 M¬/y to 377.4
M¬/y. These results have shown good future prospects for employing CO2 re-use
technology into IGCC system, as an alternative to CCS system.
Sadhukhan J (2016) Biorefinery value chain creation, Chemical Engineering Research and Design
Wan YK, Sadhukhan J, Ng KS, Ng DKS (2015) Techno-economic evaluations for feasibility of sago-based biorefinery, Part 1: Alternative energy systems, CHEMICAL ENGINEERING RESEARCH & DESIGN 107 pp. 263-279 INST CHEMICAL ENGINEERS
Lou Y, Smith R, Sadhukhan J (2008) Decarbonisation in process sites, 2008 AIChE Spring National Meeting, Conference Proceedings
This work tackles the carbon dioxide (CO2) emission problem in process sites, particularly in relation to the site utility systems.
There are three basic decarbonisation routes to deal with the CO2 emission problem in energy production. These are pre-combustion, post-combustion and the oxy-combustion routes. For each route, different CO2 separation technologies can be exploited. This work has adopted different decarbonisation routes with both conventional CO2 separation technologies and novel pre-combustion routes.

Unlike the CO2 emission problem of energy generation taken in isolation, the emissions from a utility site can be widely distributed. To challenge this problem, utility sites are integrated with decarbonised combined heat and power generation systems. By doing this, some of the utility products like power, steam and fuel can be substituted by products from the decarbonised power generation system. Consequently, reduced carbon dioxide emissions from the utility system can be achieved.

Thus, a wide range of decarbonisation designs can be applied with power generation. Among them, pre-combustion with novel CO2 separation technology has the best performance. Integrating decarbonised combined heat and power generation systems can give significant potential for CO2 emission reduction to the utility site.

Ng KS, Zhang N, Sadhukhan J (2012) A graphical CO emission treatment intensity assessment for energy and economic analyses of integrated decarbonised production systems, Computers and Chemical Engineering 45 pp. 1-14 Elsevier
Design of clean energy systems is highly complex due to the existence of a variety of CO abatement and integration options. In this study, an effective decision-making methodology has been developed for facilitating the selection of lowest energy or lowest cost intensity systems, from a portfolio of flowsheet configurations with different decarbonisation strategies. The fundamental aspect of the proposed methodology lies in thermodynamic feasibility assessment as well as quantification of CO emission treatment intensity using a graphical approach (CO emission balance diagram) for energy and economic performance analyses of integrated decarbonised systems. The relationship between the graphical representation and performances is established using blocks and boundaries on integrated systems. The effectiveness of the methodology has been demonstrated through a range of coal gasification based polygeneration and cogeneration systems, incorporating either of carbon capture and storage (CCS) or CO reuse options. © 2012 Elsevier Ltd.
Du C, Campbell GM, Misailidis N, Mateos-Salvador F, Sadhukhan J, Mustafa M, Weightman RM (2009) Evaluating the feasibility of commercial arabinoxylan production in the context of a wheat biorefinery principally producing ethanol. Part 1. Experimental studies of arabinoxylan extraction from wheat bran, Chemical Engineering Research and Design 87 (9) pp. 1232-1238
Xu M, Smith R, Sadhukhan J (2006) A bi-level optimisation approach for the productivity and thermodynamic performance of metabolic systems, AIChE Annual Meeting, Conference Proceedings
Xu M, Smith R, Sadhukhan J (2008) Optimization of productivity and thermodynamic performance of metabolic pathways, INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 47 (15) pp. 5669-5679 AMER CHEMICAL SOC
Sadhukhan J, Zhao Y, Leach M, Brandon NP, Shah N (2010) Energy Integration and Analysis of Solid Oxide Fuel Cell Based Microcombined Heat and Power Systems and Other Renewable Systems Using Biomass Waste Derived Syngas, INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 49 (22) pp. 11506-11516 AMER CHEMICAL SOC
Martinez Hernandez E, SADHUKHAN J, Campbell GM, Martinez-Herrera J (2014) Process integration, energy and GHG emission analyses of Jatropha-based biorefinery systems, Biomass Conversion and Biorefinery 4 (2) pp. 105-124 Springer Berlin Heidelberg
Driven by the need to develop a wide variety of products with low environmental impact, biorefineries need to emerge as highly integrated facilities. This becomes effective when overall mass and energy integration through a centralised utility system design is undertaken. An approach combining process integration, energy and greenhouse gas (GHG) emission analyses is shown in this paper for Jatropha biorefinery design, primarily producing biodiesel using oil-based heterogeneously catalysed transesterification or green diesel using hydrotreatment. These processes are coupled with gasification of husk to produce syngas. Syngas is converted into end products, heat, power and methanol in the biodiesel case or hydrogen in the green diesel case. Anaerobic digestion of Jatropha by-products such as fruit shell, cake and/or glycerol has been considered to produce biogas for power generation. Combustion of fruit shell and cake is considered to provide heat. Heat recovery within biodiesel or green diesel production and the design of the utility (heat and power) system are also shown. The biorefinery systems wherein cake supplies heat for oil extraction and seed drying while fruit shells and glycerol provide power generation via anaerobic digestion into biogas achieve energy efficiency of 53 % in the biodiesel system and 57 % in the green diesel system. These values are based on high heating values (HHV) of Jatropha feedstocks, HHV of the corresponding products and excess power generated. Results showed that both systems exhibit an energy yield per unit of land of 83 GJ ha?1. The global warming potential from GHG emissions of the net energy produced (i.e. after covering energy requirements by the biorefinery systems) was 29 g CO2-eq MJ?1, before accounting credits from displacement of fossil-based energy by bioenergy exported from the biorefineries. Using a systematic integration approach for utilisation of whole Jatropha fruit, it is shown that global warming potential and fossil primary energy use can be reduced significantly if the integrated process schemes combined with optimised cultivation and process parameters are adopted in Jatropha-based biorefineries.
Pask F, Lake P, Yang A, Tokos H, Sadhukhan J (2016) Industrial oven improvement for energy reduction and enhanced process performance, Clean Technologies and Environmental Policy Springer
Industrial ovens consume a considerable amount of energy and have a significant impact on product quality; therefore, improving ovens should be an important objective for manufacturers. This paper presents a novel and practical approach to oven improvement that emphasises both energy reduction and enhanced process performance. The three-phased approach incorporates product understanding, process improvement and process parameter optimisation. Cure understanding is developed using Dynamic Mechanical Analysis (DMA) and Lch-CIE colour tests, which together highlight the impact of temperature variation on cure conversion and resulting product quality. Process improvement encompasses thermodynamic modelling of the oven air to evaluate the impact of insulation on temperature uniformity and system responsiveness. Finally, process parameters, such as temperature, pressure negativity and air flow, are optimised to reduce energy consumption. The methodology has been effectively demonstrated for a 1MW festoon oven, resulting in an 87.5% reduction in cooling time, saving 202h of annual downtime and a reduction in gas consumption by 20-30%.
Ng KS, Lopez Y, Campbell GM, Sadhukhan J (2010) Heat integration and analysis of decarbonised IGCC sites, Chemical Engineering Research and Design 88 (2) pp. 170-188 Elsevier B.V. on behalf of The Institution of Chemical Engineers
Integrated gasification combined cycle (IGCC) power generation systems have become of interest due to their high
combined heat and power (CHP) generation efficiency and flexibility to include carbon capture and storage (CCS) in
order to reduce CO2 emissions. However, IGCC?s biggest challenge is its high cost of energy production. In this study,
decarbonised coal IGCC sites integrated with CCS have been investigated for heat integration and economic value
analyses. It is envisaged that the high energy production cost of an IGCC site can be offset by maximising site-wide
heat recovery and thereby improving the cost of electricity (COE) of CHP generation. Strategies for designing high
efficiency CHP networks have been proposed based on thermodynamic heuristics and pinch theory. Additionally, a
comprehensive methodology to determine the COE from a process site has been developed. In this work, we have
established thermodynamic and economic comparisons between IGCC sites with and without CCS and a trade-off
between the degree of decarbonisation and the COE from the heat integrated IGCC sites. The results show that the
COE from the heat integrated decarbonised IGCC sites is significantly lower compared to IGCC sites without heat
integration making application of CCS in IGCC sites economically competitive.
Ng KS, Zhang N, Sadhukhan J (2012) Decarbonised coal energy system advancement through CO2 utilisation and polygeneration, Clean Technologies and Environmental Policy 14 (3) pp. 443-451 Springer
Development of clean coal technology is highly
envisaged to mitigate the CO2 emission level whilst
meeting the rising global energy demands which require
highly efficient and economically compelling technology.
Integrated gasification combined cycle (IGCC) with carbon
capture and storage (CCS) system is highly efficient and
cleaner compared to the conventional coal-fired power
plant. In this study, an alternative process scheme for IGCC
system has been proposed, which encompasses the reuse of
CO2 from the flue gas of gas turbine into syngas generation,
followed by methanol synthesis. The thermodynamic
efficiency and economic potential are evaluated and
compared for these two systems. The performances of
the systems have been enhanced through systematic
energy integration strategies. It has been found that the
thermodynamic and economic feasibilities have attained
significant improvement through the realisation of a suitably
balanced polygeneration scheme. The economic
potential can be enhanced from negative impact to
317 M¬/y (3.6 ¬/GJ). The results have demonstrated
promising prospects of employing CO2 reuse technology
into IGCC system, as an alternative to CCS system.
Sadhukhan J, Zhang N, Zhu X, Smith R (2004) Analytical optimisation of industrial systems and applications to refineries, petrochemicals, AIChE Annual Meeting, Conference Proceedings pp. 7619-7626
A method for the optimizing process networks of industrial systems and applications to refineries and petrochemicals was discussed. The analytical optimization procedure was designed based on comprehensive economic analysis of process networks for maximising the overall system economics. The anaytical optimization process network comprised of three steps including marketing integration, and the optimization of network flowsheet. Marginal correlations for elements and processing of streams were developed in terms of its market price, cost of production (COP) and value on processing (VOP),and market price.
Kapil A, Bhat SA, Sadhukhan J (2010) Response to "Comments on the 'Dynamic Simulation of Sorption Enhanced Reaction Processes for Biodiesel Production", INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 49 (22) pp. 11856-11856 AMER CHEMICAL SOC
Xu M, Bhat S, Smith R, Stephens G, Sadhukhan J (2009) Multi-objective optimisation of metabolic productivity and thermodynamic performance, COMPUTERS & CHEMICAL ENGINEERING 33 (9) pp. 1438-1450 PERGAMON-ELSEVIER SCIENCE LTD
Martinez-Hernandez E, Ibrahim MH, Campbell GM, Leach M, Sinclair P, Sadhukhan J (2013) Environmental sustainability analysis of UK whole-wheat bioethanol and CHP systems, Biomass and Bioenergy
The UK whole-wheat bioethanol and straw and DDGS-based combined heat and power (CHP) generation systems were assessed for environmental sustainability using a range of impact categories or characterisations (IC): cumulative primary fossil energy (CPE), land use, life cycle global warming potential over 100 years (GWP), acidification potential (AP), eutrophication potential (EP) and abiotic resources use (ARU). The European Union (EU) Renewable Energy Directive's target of greenhouse gas (GHG) emission saving of 60% in comparison to an equivalent fossil-based system by 2020 seems to be very challenging for stand-alone wheat bioethanol system. However, the whole-wheat integrated system, wherein the CHP from the excess straw grown in the same season and from the same land is utilised in the wheat bioethanol plant, can be demonstrated for potential sustainability improvement, achieving 85% emission reduction and 97% CPE saving compared to reference fossil systems. The net bioenergy from this system and from 172,370 ha of grade 3 land is 12.1 PJ y providing land to energy yield of 70 GJ ha y. The use of DDGS as an animal feed replacing soy meal incurs environmental emission credit, whilst its use in heat or CHP generation saves CPE. The hot spots in whole system identified under each impact category are as follows: bioethanol plant and wheat cultivation for CPE (50% and 48%), as well as for ARU (46% and 52%). EP and GWP are distributed among wheat cultivation (49% and 37%), CHP plant (26% and 30%) and bioethanol plant (25%, and 33%), respectively. © 2013 Elsevier Ltd. All rights reserved.
Xu M, Wilson K, Sadhukhan J (2008) Simulation process of biodiesel production over heterogeneous catalysts, 2008 AIChE Spring National Meeting, Conference Proceedings
Biodiesel production is a very promising area due to the relevance that it is an environmental-friendly diesel fuel alternative to fossil fuel derived diesel fuels. Nowadays, most industrial applications of biodiesel production are performed by the transesterification of renewable biological sources based on homogeneous acid catalysts, which requires downstream neutralization and separation leading to a series of technical and environmental problems. However, heterogeneous catalyst can solve these issues, and be used as a better alternative for biodiesel production. Thus, a heuristic diffusion-reaction kinetic model has been established to simulate the transesterification of alkyl ester with methanol over a series of heterogeneous Cs-doped heteropolyacid catalysts. The novelty of this framework lies in detailed modeling of surface reacting kinetic phenomena and integrating that with particle-level transport phenomena all the way through to process design and optimisation, which has been done for biodiesel production process for the first time. This multi-disciplinary research combining chemistry, chemical engineering and process integration offers better insights into catalyst design and process intensification for the industrial application of Cs-doped heteropolyacid catalysts for biodiesel production. A case study of the transesterification of tributyrin with methanol has been demonstrated to establish the effectiveness of this methodology.
Sadhukhan J, Ng KS (2011) Economic and European Union Environmental Sustainability Criteria Assesment of Bio-Oil-Based Biofuel Systems: Refinery Integration Cases, INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 50 (11) pp. 6794-6808 AMER CHEMICAL SOC
The biofuel mix in transport in the U.K. must be increased from currently exploited 3.33% to the EU target mix of 10% by 2020. Under the face of this huge challenge, the most viable way forward is to process infrastructure-compatible intermediate, such as bio-oil from fast pyrolysis of lignocellulosic biomass, into biofuels. New facilities may integrate multiple distributed pyrolysis units producing bio-oil from locally available biomass and centralized biofuel production platforms, such as methanol or Fischer?Tropsch liquid synthesis utilizing syngas derived from gasification of bio-oil. An alternative to bio-oil gasification is hydrotreating and hydrocracking (upgrading) of bio-oil into stable oil with reduced oxygen content. The stable oil can then be coprocessed into targeted transportation fuel mix within refinery in exchange of refinery hydrogen to the upgrader. This Article focuses on the evaluation of economic and environmental sustainability of industrial scale biofuel production systems from bio-oils. An overview of bio-oil gasification-based system evaluation is presented, while comprehensive process reaction modeling (with 40 overall bio-oil hydrocracking and hydrotreating reaction steps), simulation, integration, and value analysis frameworks are illustrated for bio-oil upgrading and refinery coprocessing systems. The environmental analysis shows that the former technologies are able to meet the minimum greenhouse gas (GHG) emission reduction target of 60%, to be eligible for the European Union (EU) Directive?s 2020 target of 10% renewable energy in transport, while at least 20% renewable energy mix from an upgrader is required for meeting the EU GHG emission reduction target. Increases in the price of biodiesel and hydrogen make coprocessing of stable oils from bio-oil upgrader using refinery facilities economically more favorable than final biofuel blending from refineries and create win?win economic scenarios between the bio-oil upgrader and the refinery. The range of the cost of production (COP) of stable oil (328 MW or 0.424 t/t bio-oil), steam (49.5 MW or 0.926 t/t bio-oil), and off-gas or fuel gas (72.3 MW or 0.142 t/t bio-oil) from a bio-oil (LHV of 23.3 MJ/kg) upgrader process is evaluated on the basis of individual product energy values and global warming potential (GWP) impacts. The minimum and the maximum annualized capital charges predicted by the Discounted Cash Flow (DCF) analysis correspond to 25 operating years and 10% IRR, an
Xu M, Sadhukhan J, Wilson K (2008) Dynamic modeling of transesterification in a simulated moving bed chromatographic reactor for biodiesel production, 2008 AIChE Annual Meeting, Conference Proceedings
Biodiesel production is a very promising subject due to the relevance that it is environmental-friendly and an alternative diesel fuel for fossil fuel. Nowadays, most industrial applications of biodiesel production are performed by the transesterification of renewable biological sources based on heterogeneous catalysts, which requires separate reaction and separation processes. And the conversion of the reaction is restricted due to its equilibrium limitation. Thus, in this work, a simulated moving bed chromatographic reactor (SMBR) has been applied for the first time into the transesterification of biodiesel production, which allows us to carry out a simultaneous reaction and separation process and drive the transesterification reaction beyond its equilibrium. A detailed dynamic modeling of reaction as well as continuous adsorptive separation based on the surface reacting kinetic phenomena integrating with particle-level transport phenomena has been established firstly for a SMBR process design and optimization. This research offers a heuristic insight into the improvement of industrial production of biodiesel. A case study of the transesterification of tributyrin with methanol over hydrotalcite catalysts has been demonstrated to establish the effectiveness of this methodology.
Sadhukhan J, Simons HJ (2005) Cleaner technology evolutions for refineries, 7th World Congress of Chemical Engineering, GLASGOW2005, incorporating the 5th European Congress of Chemical Engineering
It was established that olefin cracker and gasification technologies provide solutions to today's refineries by marketing unwanted, heavy, high sulfur, TAN materials though environmentally benign, highly valuable productions. To a refinery, these technologies offer reaction operations like hydrocracking, catalytic reforming etc. However, they convert the various fractions of oils including heavy, high sulfur, TAN oils to more valuable primary petrochemicals, hydrogen, power, and energy. Due to high investment and maintenance costs of these two processes their applications are limited to refineries. However, in recent years when the environmental legislations on fuel qualities and emissions demand a complete disposal of bottom fractions into sustainable products, while ensuring a steady economic gain, integration of these two technologies to refineries seems to be the most promising option. Economic justification is achieved in the following ways. A high valued product slate consisting of polymer grade olefins (ethylene, propylene), hydrogen, transportation fuels (gasoline, diesel), power and energy with significantly lower emissions is resulted from complete bottom of barrel disposal. No heavy products, fuel oils, residues are produced having lower value than crude oils. Today's refinery should ideally employ a limited number of selective technologies: crude distillation, hydrotreating, olefin cracking, resid processing (e.g. solvent deasphalting, delayed coking), integrated gasification combined cycle (IGCC). Use of advanced process integration tools and development of process technologies particularly in the areas of olefin cracking, IGCC offer additional prospects of economic growth in refineries. This is an abstract of a paper presented at the 7th World Congress of Chemical Engineering (Glasgow, Scotland 7/10-14/2005).
Mateos-Salvador F, Sadhukhan J, Campbell GM (2013) Extending the Normalised Kumaraswamy Breakage Function for roller milling of wheat flour stocks to Second Break, Powder Technology 237 pp. 107-116
The Normalised Kumaraswamy Breakage Function (NKBF), developed previously to describe First Break milling of wheat kernels, was applied here to describe the breakage of the stocks produced by First Break that then pass to Second Break milling. The breakage equation for roller milling assumes independent breakage of particles as they pass through the mill; that assumption was tested for Second Break milling and found to be appropriate. A single NKBF was not adequate to describe the full particle size distribution (PSD) created by Second Break milling, as the PSD is bimodal, and the NKBF is unimodal. Instead, the PSD was divided into the fraction of particles larger than 2000. ¼m, and those smaller than 2000. ¼m, and separate NKBF functions were applied to each fraction. In this way, it was demonstrated that the size distribution of particles larger than 2000. ¼m produced after Second Break milling depended strongly on the input particle size, but was essentially independent of the roll gap used for Second Break. By contrast, the PSD of particles smaller than 2000. ¼m depended strongly on the roll gap, but was essentially independent of the input particle size. This finding reflects the nature of Second Break milling, that it involves scraping endosperm material off bran particles, such that the endosperm material (which is produced as small particles) depends strongly on the size of the gap through which the bran particle passes, but the bran particle itself remains essentially intact, irrespective of roll gap. This scraping of endosperm particles, although strongly dependent on the roll gap, is independent of the size of the bran particles, because the bran particles pass through the roll gap oriented along their longest dimensions. Second Break milling of the entire output from First Break, as practised in double high systems, could be described adequately by a single NKBF. Extending the breakage equation via the NKBF to Second Break facilitates the application of simulation and optimisation to flour milling for both food and non-food processes. © 2013 Elsevier B.V.
Sadhukhan J, Smith R (2005) Analytical optimisation of industrial ms based on economic analysis, 7th World Congress of Chemical Engineering, GLASGOW2005, incorporating the 5th European Congress of Chemical Engineering
A methodology for detailed differential economic analysis of industrial systems based on an analytical optimization procedure is presented. Existing process integration methodologies for large scale industrial systems (refineries, petrochemicals, chemicals) where a number of processes, streams, and supporting systems are involved, do not provide economic value structure of individual components prior to optimization. Such problems are overcome through an economic analysis of streams and processes in a system. A novel optimization method called analytical optimization for process industries is developed. An overall integration strategy is then developed to capture the impacts of variable operating conditions and complex network connections in the detailed differential economic analysis of systems. The methodology is applied in the design and synthesis of an oil upgrading system. This is an abstract of a paper presented at the 7th World Congress of Chemical Engineering (Glasgow, Scotland 7/10-14/2005).
Kapil A, Wilson K, Lee AF, Sadhukhan J (2011) Kinetic Modeling Studies of Heterogeneously Catalyzed Biodiesel Synthesis Reactions, Industrial and Engineering Chemistry Research 50 (9) pp. 4818-4830 AMER CHEMICAL SOC
The heterogeneously catalyzed transesterification reaction for the production of biodiesel from triglycerides was
investigated for reaction mechanism and kinetic constants. Three elementary reaction mechanisms Eley-Rideal (ER), Langmuir-
Hinshelwood-Hougen-Watson (LHHW), andHattori with assumptions, such as quasi-steady-state conditions for the surface species
andmethanol adsorption, and surface reactions as the rate-determining steps were applied to predict the catalyst surface coverage and the
bulk concentration using a multiscale simulation framework. The rate expression based on methanol adsorption as the rate limiting in
LHHW elementary mechanism has been found to be statistically the most reliable representation of the experimental data using
hydrotalcite catalyst with different formulations.
Sadhukhan J, Zhao Y, Shah N, Brandon NP (2010) Performance analysis of integrated biomass gasification fuel cell (BGFC) and biomass gasification combined cycle (BGCC) systems, CHEMICAL ENGINEERING SCIENCE 65 (6) pp. 1942-1954 PERGAMON-ELSEVIER SCIENCE LTD
Process to process material and heat integration strategies for bio-oil integrated gasification
and methanol synthesis (BOIG-MeOH) systems were developed to assess their technological
and economic feasibility. Distributed bio-oil generations and centralised processing
enhance resource flexibility and technological feasibility. Economic performance depends
on the integration of centralised BOIG-MeOH processes, investigated for cryogenic air
separation unit (ASU) and water electrolyser configurations. Design and operating variables
of gasification, heat recovery from gases, water and carbon dioxide removal units, water-gas
shift and methanol synthesis reactors and CHP network were analysed to improve the
overall efficiency and economics. The efficiency of BOIG-MeOH system using bio-oil from
various feedstocks was investigated. The system efficiency primarily attributed by the
moisture content of the raw material decreases from oilseed rape through miscanthus to
poplar wood. Increasing capacity and recycle enhances feasibility, e.g.1350MWBOIG-MeOH
with ASU and 90% recycle configuration achieves an efficiency of 61.5% (methanol, low
grade heat and electricity contributions by 89%, 7.9% and 3% respectively) based on poplar
wood and the cost of production (COP) of methanol of 318.1 Euro/t for the prices of bio-oil of
75 Euro/t and electricity of 80.12 Euro/MWh, respectively. An additional transportation cost
of 4.28e8.89 Euro/t based on 100 km distance between distributed and centralised plants
reduces the netback of bio-oil to 40.9e36.3 Euro/t.
Miah JH, Griffiths A, McNeill R, Poonaji I, Martin R, Morse S, Yang A, Sadhukhan J (2015) Creating an environmentally sustainable food factory: A case study of the Lighthouse project at Nestlé, Procedia CIRP 26 pp. 229-234
Many manufacturing companies recognise the need to produce products that are cleaner, greener, and environmentally sustainable, yet they are only at the early stages of this transition in addressing the symptoms of unsustainability at their direct operations by reducing waste and the use of energy, water and material. The implementation of reductions in these areas can be disparate and minimal given the life cycle of a product. Bridging the gap between the rhetoric of sustainable manufacturing and reality requires a holistic, systems thinking approach to ensure the implementation of sustainability is unified and strategic. This paper presents a novel environmentally sustainable manufacturing framework that encompasses energy, water, waste, biodiversity, and people & community. It adopts a systems thinking perspective to address the factories ?environmental life cycle impact to deliver factory and supply chain benefits. The insights from the application at a Nestlé confectionery factory are reported.
Pask F, Sadhukhan J, Lake P, McKenna S, Perez E, Yang A (2014) Practical approach for engineers to optimise industrial ovens for energy saving, Chemical Engineering Transactions 39 (Special Issue) pp. 865-870
Copyright © 2014, AIDIC Servizi S.r.l.Energy saving within the manufacturing sector has a role to play in reducing global energy consumption and green house gas emissions. Despite heating applications being common throughout industry, there is currently no framework that provides practical guidance for energy optimisation in ovens. This paper presents a systematic approach to guide an engineer through five stages of optimisation. It begins with defining the problem and system boundaries, before developing a thorough understanding of the oven system through mass balance and energy analysis as well as identifying all process variables. Analysis of key process variables is conducted to develop process & product understanding and to identify key variables. Improvement of the system and then controlling for full implementation leads to successful conclusion of the project. Application of this methodology has been conducted on curing oven for masking tape manufacture. The optimisation results in a potential 4.7 % annual reduction of the plants energy consumption and off-setting 305 teCO2 from minimal capital expenditure. As the methodology can be tailored to accommodate individual optimisation options for each oven scenario, while still providing a clear pathway, it has potential to reduce energy within the wider manufacturing industry.
Miah JH, Griffiths A, McNeill R, Poonaji I, Martin R, Leiser A, Morse S, Yang A, Sadhukhan J (2015) Maximising the recovery of low grade heat: An integrated heat integration framework incorporating heat pump intervention for simple and complex factories, Applied Energy 160 pp. 172-184 Elsevier
The recovery of heat has long been a key measure to improving energy efficiency and maximising the heat recovery of factories by Pinch analysis. However, a substantial amount of research has been dedicated to conventional heat integration where low grade heat is often ignored. Despite this, the sustainability challenges facing the process manufacturing community are turning interest on low grade energy recovery systems to further advance energy efficiency by technological interventions such as heat pumps. This paper presents a novel heat integration framework incorporating technological interventions for both simple and complex factories to evaluate all possible heat integration opportunities including low grade and waste heat. The key features of the framework include the role of heat pumps to upgrade heat which can significantly enhance energy efficiency; the selection process of heat pump designs which was aided by the development of ?Heat Pump Thresholds? to decide if heat pump designs are cost-competitive with steam generation combustion boiler; a decision making procedure to select process or utility heat integration in complex and diverse factories; and additional stream classifications to identify and separate streams that can be practically integrated. The application of the framework at a modified confectionery factory has yielded four options capable of delivering a total energy reduction of about 32% with an economic payback period of about 5 years. In comparison, conventional direct and/or indirect heat integration without heat pumps showed an energy reduction potential of only 3.7?4.3%. Despite the long payback, the role of heat pumps combined with an integrated search by direct and indirect heat exchange from zonal to factory level can provide the maximum heat recovery. The framework has the potential to be applied across the process manufacturing community to inform longer-term energy integration strategies.
Sadhukhan J, Smith R (2007) Synthesis of industrial systems based on value analysis, COMPUTERS & CHEMICAL ENGINEERING 31 (5-6) pp. 535-551 PERGAMON-ELSEVIER SCIENCE LTD
Misailidis N, Campbell GM, Du C, Sadhukhan J, Mustafa M, Mateos-Salvador F, Weightman RM (2009) Evaluating the feasibility of commercial arabinoxylan production in the context of a wheat biorefinery principally producing ethanol Part 2. Process simulation and economic analysis, CHEMICAL ENGINEERING RESEARCH & DESIGN 87 (9A) pp. 1239-1250 INST CHEMICAL ENGINEERS
Campbell G, Koutinas A, Wang R, Sadhukhan J, Webb C (2006) Biofuels 1: Cereal potential, Chemical Engineer (781) pp. 26-28
A discussion covers the challenge of engineering cereal-based biorefineries; argument that cereals are the best raw material option for a sustainable chemical industry; economic issues; success factors, e.g., process engineering innovations and the chemistry of extraction and transformation of cereal components; genetic modification of cereals; and implications on the education of process engineers.
Xu M, Sadhukhan J (2008) Kinetics of heterogeneously catalyzed triglyceride transesterification: A new simulation framework for biodiesel production, 2008 AIChE Spring National Meeting, Conference Proceedings
Biodiesel, an alternative diesel fuel, has become more attractive recently because of its environmental benefits and the increase in the petroleum price. Nowadays, most industrial applications of biodiesel production are performed by the transesterification of renewable biological sources based on homogeneous acid catalysts, which requires downstream neutralization and separation leading to a series of technical and environmental problems. However, heterogeneous catalyst can solve these issues, and be used as a better alternative for biodiesel production. Thus, a heuristic diffusion-reaction kinetic model has been established to simulate the transesterification of alkyl ester with methanol over a series of heterogeneous Cs-doped heteropolyacid catalysts. The novelty of this framework lies in detailed modeling of surface reacting kinetic phenomena and integrating that with particle-level transport phenomena all the way through to process design and optimisation, which has been done for biodiesel production process for the first time. This multi-disciplinary research combining chemistry, chemical engineering and process integration offers better insights into catalyst design and process intensification for the industrial application of Cs-doped heteropolyacid catalysts for biodiesel production. A case study of the transesterification of tributyrin with methanol has been demonstrated to establish the effectiveness of this methodology.
Xu M, Wilson K, Sadhukhan J (2008) Simulation of heterogeneously Cs-doped heteropolyacid catalyzed transesterification for biodiesel production, Catalysis and Reaction Engineering Division Conference, Presentations at the 2008 AIChE Spring National Meeting pp. 67-74
Zhao Y, Sadhukhan J, Lanzini A, Brandon N, Shah N (2011) Optimal integration strategies for a syngas fuelled SOFC and gas turbine hybrid, JOURNAL OF POWER SOURCES 196 (22) pp. 9516-9527
Davison TJ, Okoli C, Wilson K, Lee AF, Harvey A, Woodford J, Sadhukhan J (2013) Multiscale modelling of heterogeneously catalysed transesterification reaction process: an overview, RSC ADVANCES 3 (18) pp. 6226-6240 ROYAL SOC CHEMISTRY
Sadhukhan J, Zhang N, Zhu XX, Smith R (2004) Analytical optimisation of industrial systems and applications to refineries, petrochemicals, AIChE Annual Meeting, Conference Proceedings
A new method for optimizing process networks is presented. The method uses economic analysis of existing systems based on the value analysis method derived by Sadhukhan (2002) as the basis to derive the optimum network design. Optimizing a large scale industrial system (e.g., refineries, petrochemicals) where multiple processes, many material streams and a number of supporting systems (e.g., energy) are involved, is a difficult task to achieve. The methodology is conceived in consideration to exploit opportunities existing in both the market as well as in the site to the fullest extent. The proposed optimization procedure uses analytical insights to integrate and optimize process networks. The procedure is built upon economic analysis at the basic stream and process level. The resulting network flowsheet includes the profitable connections and gets rid of the non-profitable connections. The opportunities in the existing infrastructure are fully exploited to result in an overall network integration. This is an abstract of a paper presented at the AIChE Annual Meeting (Austin, TX 11/7-12/2004).
Miah JH, Griffiths A, McNeill R, Poonaji I, Martin R, Morse S, Yang A, Sadhukhan J (2015) A small-scale transdisciplinary process to maximising the energy efficiency of food factories: insights and recommendations from the development of a novel heat integration framework, Sustainability Science 10 (4) pp. 621-637 Springer
The rise and uncertainty in energy prices in recent years has widened the solution search space by industry to understand the full impacts on operations and to develop a range of workable solutions to reduce risk. This has involved companies exploring alternative approaches to co-create solutions with different groups comprising varying intellectual capital, e.g. consultants, NGOs, and academia. This paper presents the small-scale transdisciplinary process adopted by Nestlé UK in partnership with the University of Surrey as part of an Engineering Doctorate (EngD) programme to co-develop a heat integration framework to improve the energy efficiency of a confectionery factory. The small-scale co-creation process?between industry and academia?for a heat integration framework is described and includes a set of criteria to evaluate the effectiveness of the process. The results of the evaluation process and a reflection of the key challenges and implications faced when trying to implement a small-scale transdisciplinary process are reported which covers the role of an EngD researcher as a manager, facilitator and researcher, time management, finance, communication, knowledge integration, mutual learning, and conflict. Some of the key recommendations for industrial practitioners include: actively engaging in the transdisciplinary process on a consistent basis, staying open minded to developing a solution even when there is a lack of progress, and building relationships with academics by supporting university activities, e.g. lecturing, research projects and funding proposals. For scientists, PhD students, research institutes, and private and public R&D, some of the key recommendations include: communicating expert knowledge to a few points rather than opening out into a lecture, contributing to the transdisciplinary process even if it is on a non-expert level but provides objective and critical input, and visiting industrial sites to gain exposure to industrial problems first-hand. Overall, the range of recommendations provided can help both industrial practitioners and scientists, especially doctoral students seeking to operate in the industry?academia domain on a small?practically manageable?scale.
Sadhukhan J, Ng KS, Shah N, Simons HJ (2009) Heat Integration Strategy for Economic Production of Combined Heat and Power from Biomass Waste, Energy Fuels 23 (10) pp. 5106-5120 American Chemical Society
The objective of this work was to design a heat integrated, cost-effective, and cleaner combined heat and power (CHP) generation plant from low-cost, fourth-generation biomass waste feedstocks. The novelty lies in the development of systematic sitewide heat recovery and integration strategies among biomass integrated gasification combined cycle processes so as to offset the low heating value of the biomass waste feedstocks. For the biomass waste based CHP plant technical and economic analysis, the process was based on low-cost agricultural wastes like straws as the biomass feedstock and further established for a more predominant biomass feedstock, wood. The process was modeled using the Aspen simulator. Three conceptual flowsheets were proposed, based on the integration of the flue gas from the char combustor, which was separately carried out from the steam gasification of biomass volatalized gases and tars, and carbon dioxide removal strategies. The cost of energy production included detailed levelized discounted cash flow analysis and was found to be strongly influenced by the cost of feedstock. On the basis of a combined energy generation of 340?370 MW using straw wastes priced at 35.3 £/t or 40 Euro/t, with 8.5% and 8.61% by mass moisture and ash contents, respectively, the cost of electricity generation was 4.59 and 5.14 p/(kW h) for the cases without and with carbon capture respectively, with a 10% internal rate of return and 25 years of plant life. On the basis of the carbon capture value assigned by the Carbon Credits Trading scheme, a much constrained viable price of 22 £/t of such agricultural waste feedstocks for CHP generation was obtained, while up to 60 £/t of waste feedstocks can be economically viable under the UK Climate Change Levy, respectively.
Martinez-Hernandez E, Sadhukhan J, Campbell GM (2013) Integration of bioethanol as an in-process material in biorefineries using mass pinch analysis, Applied Energy 104 pp. 517-526 Elsevier
A biorefinery involving internal stream reuse and recycling (including products and co-products) should result in better biomass resource utilisation, leading to a system with increased efficiency, flexibility, profitability and sustainability. To benefit from those advantages, process integration methodologies need to be applied to understand, analyse and design highly integrated biorefineries. A bioethanol integration approach based on mass pinch analysis is presented in this work for the analysis and design of product exchange networks formed in biorefinery pathways featuring a set of processing units (sources and demands) producing or utilising bioethanol. The method is useful to identify system debottleneck opportunities and alternatives for bioethanol network integration that improve utilisation efficiency in biorefineries with added value co-products. This is demonstrated by a case study using a biorefinery producing bioethanol from wheat with arabinoxylan (AX) co-production using bioethanol for AX precipitation. The final integrated bioethanol network design allowed the reduction of bioethanol product utilisation by 94%, avoiding significant revenue losses. © 2012 Elsevier Ltd.
Sadhukhan J, Zhang N, Zhu X (2004) Analytical optimisation of industrial systems and applications to refineries, petrochemicals, Chemical Engineering Science 59 (20) pp. 4169-4192
A new method for optimising process networks is presented in this paper. The method uses economic analysis of existing systems based on the new value analysis method (Ph.D. Dissertation, UMIST, Manchester, UK, 2002) as the basis to derive the optimum network design. The analytical optimisation method comprises of three steps. Market integration is the first step that fully exploits the available market opportunities for selling and purchasing streams based on individual marginal contributions from productions and processing of streams. Market integration is an easy and straightforward way of achieving quick benefits. The second step deals with optimisation of network flowsheet/connections. The economic margins of various paths of network are used to determine the weaker paths and the stronger paths where the loads of weaker paths can be shifted. This load shifting among paths leads up to the overall benefits of a system, Finally, the non-profitable or less profitable process units are optimised to improve their individual marginal contributions. Analytical optimisation turns the traditional back box approach into a clear and transparent procedure and is simple to understand and easy to use. The application of analytical optimisation is demonstrated with industrial cases from refining. In the end, a generalised methodology has been illustrated on how to design the optimum flowsheet of a petrochemical complex in a changing market price scenario. © 2004 Elsevier Ltd. All rights reserved.
Lou Y, Hannan A, Sadhukhan J (2006) A flowsheet design methodology for the decarbonised energy systems via hydrogen from hydrocarbons, AIChE Annual Meeting, Conference Proceedings
Hydrogen is the most attractive decarbonized fuel leaving only water after power generation. A discussion covers a a novel methodology for the designing the process flowsheets from raw material to end products that utilize the light, e.g., natural gas, to heavy hydrocarbons for decarbonized energy generation; exploitation of poly-generation opportunities; use of pure hydrogen for power and heat generation; sequestration of CO2 for geological formations and EOR from oil wells/reservoirs; a three stage systematic methodology to assist the design of decarbonized energy generation flowsheets from the hydrocarbons; tuning the design and operation of the flowsheets; and an industrial case study that presents a systematic comparison and the tradeoffs between the sorption enhanced reaction processes and the membrane reactors for the decarbonized energy generation. This is an abstract of a paper presented at the 2006 AIChE Annual Meeting (San Francisco, CA 11/12-17/2006).
Sadhukhan J, Zhang N, Zhu XX (2003) Value analysis of complex systems and industrial application to refineries, Industrial and Engineering Chemistry Research 42 (21) pp. 5165-5181
A generalized strategy for the modeling and integration of an overall system is developed for the purpose of detailed economic analysis of industrial systems. The work uses the basics of value analysis method (Sadhukhan, J. Ph.D. Dissertation, UMIST, Manchester, U.K., 2002) to identify major material streams and their elements of production and processing. These major material streams are evaluated for economics, and these economics are used to predict the economics of elements of production and processing expressed as profit functions of process units. However, in a complex network system, there exist a variety of streams forming a number of processing networks in addition to the core system of major material streams and utilities. To consider the effects of overall network interactions in the economics of major material streams and elements, these processing networks are modeled interchangeably as material or utility networks and integrated with the core system of major material streams and utilities. Further, these economics of streams and elements are used to establish the overall system economics and thereby capturing the effects of overall network interactions in the overall system economics. The insights developed to build economic models at various stages are illustrated with several examples and an industrial case study from a refinery. In addition to the economic analysis of an overall refining system, the refinery crude switch problem is used to demonstrate the application of system economic analysis to optimum feedstock selection.
Mateos-Salvador F, Sadhukhan J, Campbell GM (2011) The normalised Kumaraswamy breakage function: A simple model for wheat roller milling, POWDER TECHNOLOGY 208 (1) pp. 144-157 ELSEVIER SCIENCE SA
Bhat SA, Sadhukhan J (2009) Process Intensification Aspects for Steam Methane Reforming: An Overview, AICHE JOURNAL 55 (2) pp. 408-422 JOHN WILEY & SONS INC
Niekamp S, Bharadwaj UR, Sadhukhan J, Chryssanthopoulos MK (2015) A multi-criteria decision support framework for sustainable asset management and challenges in its application, Journal of Industrial and Production Engineering 32 (1) pp. 44-57
Despite an increasing demand for considering sustainability aspects in asset management, there is a lack of guidance for decision-makers on how this can be achieved. The aim of this research is to present rational decision support for sustainable management of industrial assets in situations where there are multiple conflicting objectives. For this purpose, a Multi-criteria decision analysis framework that incorporates sustainability criteria over the whole life cycle has been developed. Stakeholder participation and uncertainty assessment are considered explicitly allowing for a holistic perspective and higher confidence in the results. In order to facilitate communication, methods for visualization of numerical results are highlighted. While the focus of this study is on the development of the framework, the challenges of applying it and potential steps to address these are discussed through an application in the shipping sector.
Campbell G, Koutinas A, Wang R, Sadhukhan J, Webb C (2006) Cereal potential, TCE (781) pp. 26-28 INST CHEMICAL ENGINEERS
Xu M, Wilson K, Sadhukhan J (2008) Simulation of heterogeneously Cs-doped heteropolyacid catalyzed transesterification for biodiesel production, 2008 AIChE Spring National Meeting, Conference Proceedings
Biodiesel, an alternative diesel fuel, has become more attractive recently because of its environmental benefits and the increase in the petroleum price. Nowadays, most industrial applications of biodiesel production are performed by the transesterification of renewable biological sources based on homogeneous acid catalysts, which requires downstream neutralization and separation leading to a series of technical and environmental problems. However, heterogeneous catalyst could solve these issues, and be used as a better alternative for biodiesel production. Thus, a heuristic diffusion-reaction kinetic model has been established to simulate the transesterification of alkyl ester with methanol over a series of heterogeneous Cs-doped heteropolyacid catalysts. The novelty of this framework lies in detailed modeling of surface reacting kinetic phenomena and integrating that with particle-level transport phenomena all the way through to process design and optimisation. A kinetic model based on a three-step ?Eley-Rideal' type of mechanism in the liquid phase is used in the simulation of reaction. The effect of diffusion inside a catalyst pellet is taken into account because of the mass transport inside the catalyst particles. This multi-disciplinary research offers better insights into catalyst design and process intensification for the industrial application of Cs-doped heteropolyacid catalysts for biodiesel production. A case study of the transesterification of tributyrin with methanol has been demonstrated to establish the effectiveness of this methodology.
Sadhukhan J, Zhu XX (2002) Integration strategy of gasification technology: A gateway to future refining, Industrial and Engineering Chemistry Research 41 (6) pp. 1528-1544
Stricter environmental legislation on emissions, product qualities, and the increased availability of heavier and sourer crudes are the main driving forces for refineries to use gasification technologies for the "bottom of the barrel" disposal into production of hydrogen and clean energy. However, economic viability needs to be fully proven. This paper takes the challenge of integrating gasification to an overall refinery. To achieve this, a four stage optimization strategy is developed. In the screening and scoping stage, the energy integration opportunities are explored. In site level optimization, the overall integration among refinery and gasification is considered to maximize the margin. In process level optimization, appropriate integration among gasification, hydrogen, and utility systems is derived to minimize the investment. Finally, the simultaneous optimization of site and process levels is carried out to trade off between benefits and investment. By applying this methodology to a refinery case study, signific marginal improvement is achieved with minimal investment.
Sadhukhan J, Martinez-Hernandez E (2017) Material Flow and Sustainability Analyses of Biorefining of Municipal Solid Waste, Bioresource Technology 243 pp. 135-146 Elsevier
This paper presents material flow and sustainability analyses of novel mechanical biological chemical treatment system for complete valorization of municipal solid waste (MSW). It integrates material recovery facility (MRF); pulping, chemical conversion; effluent treatment plant (ETP), anaerobic digestion (AD); and combined heat and power (CHP) systems producing end products: recyclables (24.9% by mass of MSW), metals (2.7%), fibre (1.5%); levulinic acid (7.4%); recyclable water (14.7%), fertiliser (8.3%); and electricity (0.126 MWh/t MSW), respectively. Refuse derived fuel (RDF) and non-recyclable other waste, char and biogas from MRF, chemical conversion and AD systems, respectively, are energy recovered in the CHP system. Levulinic acid gives profitability independent of subsidies; MSW priced at 50 Euro/t gives a margin of 204 Euro/t. Global warming potential savings are 2.4 and 1.3 kg CO2 equivalent per kg of levulinic acid and fertiliser, and 0.17 kg CO2 equivalent per MJ of grid electricity offset, respectively.
Sadhukhan J, Joshi N, Shemfe M, Lloyd J (2017) Life Cycle Assessment of Sustainable Raw Material Acquisition for Functional Magnetite Bionanoparticle Production, Journal of Environmental Management 199 pp. 116-125 Elsevier
Magnetite nanoparticles (MNPs) have several applications, including use in medical diagnostics, renewable energy production and waste remediation. However, the processes for MNP production from analytical-grade materials are resource intensive and can be environmentally damaging. This work for the first time examines the life cycle assessment (LCA) of four MNP production cases: (i) industrial MNP production system; (ii) a state-of-the-art MNP biosynthesis system; (iii) an optimal MNP biosynthesis system and (iv) an MNP biosynthesis system using raw materials sourced from wastewaters, in order to recommend a sustainable raw material acquisition pathway for MNP synthesis. The industrial production system was used as a benchmark to compare the LCA performances of the bio-based systems (cases ii-iv). A combination of appropriate life cycle impact assessment methods was employed to analyse environmental costs and benefits of the systems comprehensively. The LCA results revealed that the state-of-the-art MNP biosynthesis system, which utilises analytical grade ferric chloride and sodium hydroxide as raw materials, generated environmental costs rather than benefits compared to the industrial MNP production system. Nevertheless, decreases in environmental impacts by six-fold were achieved by reducing sodium hydroxide input from 11.28 to 1.55 in a mass ratio to MNPs and replacing ferric chloride with ferric sulphate (3.02 and 2.59, respectively, in a mass ratio to MNPs) in the optimal biosynthesis system. Thus, the potential adverse environmental impacts of MNP production via the biosynthesis system can be reduced by minimising sodium hydroxide and substituting ferric sulphate for ferric chloride. Moreover, considerable environmental benefits were exhibited in case (iv), where Fe(III) ions were sourced from metal-containing wastewaters and reduced to MNPs by electrons harvested from organic substrates. It was revealed that 14.4 kJ and 3.9 kJ of primary fossil resource savings could be achieved per g MNP and associated electricity recoveries from wastewaters, respectively. The significant environmental benefits exhibited by the wastewater-fed MNP biosynthesis system shows promise for the sustainable production of MNPs.
Sadhukhan J, Mustafa MA, Misailidis N, Mateos-Salvador F, Du C, Campbell GM (2008) Value analysis tool for feasibility studies of biorefineries integrated with value added production, CHEMICAL ENGINEERING SCIENCE 63 (2) pp. 503-519 PERGAMON-ELSEVIER SCIENCE LTD
Kapil A, Masters A, Sadhukhan J (2009) A multiscale model for determination of kinetic rate constants for hydrotalcite catalyzed biodiesel synthesis, Conference Proceedings - 2009 AIChE Spring National Meeting
Biodiesel is a renewable, environmentally friendly fuel. Commercially most biodiesel is produced from the esterification reaction of vegetable oil with methanol in the presence of a homogeneous catalyst 1. Heterogeneous catalysis however lowers the cost of production by reducing the number of downstream processes. There have been some experimental studies on hydrotalcite as a heterogeneous catalyst2, but little work has been done on the modelling of the process. To evaluate the industrial applicability of the heterogeneous catalyzed process, we have developed a multiscale model for hydrotalcite catalyzed transesterification using a hybrid Monte Carlo/mean field approach. The spatial distribution of species on the catalyst surface is an important factor in determining the reaction rate and this can be taken into account by the application of Kinetic Monte Carlo3. An Eley-Rideal type mechanism is used to model the reactions on the catalyst surface. The overall reaction rate expressions have been derived based on the assumption of quasi steady state conditions for the surface species. We have used a novel hybrid model based on elementary reaction steps to increase the accuracy and robustness of the overall reaction kinetic expression and hence the design of the reactor. This model can be further extended to determine optimum catalyst properties and bulk conditions.
Wan YK, Sadhukhan J, Ng DKS (2015) Techno-economic evaluations for feasibility of sago-based biorefinery, Part 2: Integrated bioethanol production and energy systems, CHEMICAL ENGINEERING RESEARCH & DESIGN 107 pp. 102-116 INST CHEMICAL ENGINEERS
Xu M, Smith R, Sadhukhan J (2006) A bi-level optimisation approach for the productivity and thermodynamic performance of metabolic systems, AIChE Annual Meeting, Conference Proceedings
A metabolic network is most often interpreted and modeled in terms of a collection of enzyme-catalyzed reactions with transport phenomena that utilise substrate metabolites to generate final metabolites. The complexity of the metabolic reaction systems necessitates the development of the integrated approaches to analyse and interpret the systemic properties of cellular metabolism, which shifts the emphasis from single metabolic reactions to systemic pathways defined by elementary flux mode (EFM) analysis. In this work a methodology is developed to establish a rational metabolic engineering strategy for the elucidation and optimisation of metabolic systems, by combining the metabolic flux analysis (MFA) and pathway identification with the thermodynamic analysis of the metabolic system. A bi-level optimisation strategy has been developed to predict the optimal pathways for the maximum productivity and the operating conditions / performance in the first and the second level respectively, for achieving the desired objectives. In the first level, a systematic enumeration of pathways is described by the elementary flux mode (EFM) analysis, which provides a mathematical tool to define and comprehensively describe all metabolic routes that are both stoichiometrically and thermodynamically feasible for a group of enzymes. The optimal metabolic flux distribution and the corresponding pathways are identified by LP optimisation subjecto to the stoichiometric flux balance analysis (FBA) and the constrains on negative gibbs free energy change, for achieving the maximum yield of products. In the second level, thermodynamic optimisation in terms of the Gibbs free energy change minimisation is carried out for the best performance of the system. The Gibbs free energy changes are predicted for the stoichiometrically balanced sequences of pathways from for the energetic coupling between metabolites. The Gibbs free energy of metabolites in this model is presented as a function of temperature, pressure, pH and metal ions concentrations. Hence the minimisation of the Gibbs free energy change optimises these operating conditions, for the optimal pathways that achieve the desired objectives on productions. This two stage optimisation approach is integrated through the flux balance analysis, the elementary flux mode analysis, the inequality constraints on the negative Gibbs free energy change and the calculation of metabolites formation gibbs energy. The optimisation procedure thus
Despite some success with microbial fuel cells and microbial electrolysis cells in recovering resources from wastes, challenges with their scale and yield need to be resolved. Waste streams from biorefineries e.g. bioethanol and biodiesel plants and wastewaters are plausible substrates for microbial electrosynthesis (MES). MES integration can help biorefineries achieving the full polygeneration potentials, i.e. recovery of metals turning apparently pollutants from biorefineries into resources, production of biofuels and chemicals from reuse of CO2 and clean water. Symbiotic integration between the two systems can attain an economic and environmental upside of the overall system. We envision that electrochemical technologies and waste biorefineries can be integrated for increased efficiency and competitiveness with stillage released from the latter process used in the former as feedstock and energy resource recovered from the former used in the latter. Such symbiotic integration can avoid loss of
2
material and energy from waste streams, thereby increasing the overall efficiency, economics and environmental performance that would serve towards delivering the common goals from both the systems. We present an insightful overview of the sources of organic wastes from biorefineries for integration with MES, anodic and cathodic substrates and biocatalysts. In addition, a generic and effective reaction and thermodynamic modelling framework for the MES has been given for the first time. The model is able to predict multi-component physico-chemical behaviour, technical feasibility and best configuration and conditions of the MES for resource recovery from waste streams.
Martinez-Hernandez E, Sadhukhan J, Campbell GM (2014) Economic and environmental impact marginal analysis of biorefinery products for policy targets, Journal of Cleaner Production
A simple biofuel production system can be first examined for its policy compliance in terms of GHG emission reduction target relative to fossil-based counterparts. More integrated and optimised biorefinery systems with polygeneration can then be evolved with the aid of graphical analysis of marginal emission savings vs. additional economic margins. This bottom-up approach helps to achieve greater GHG emission cut by integrated systems design and thereby setting a more stringent benchmark to support policies towards achieving climate change mitigation goals. The combined Economic Value and Environmental Impact analysis is a multi-level methodology that can be used to represent biorefinery system performances as an aggregate of differential economic and environmental impact margins of biorefinery products. The methodology is extended in this paper to support process integration strategies that allow achieving policy compliance of biorefinery products in terms of GHG emission savings. An economic and environmental impact profile of the products is introduced for a graphical visualisation of economic costs and values as well as deficits and surpluses in environmental impact savings. The effectiveness of the extended methodology has been demonstrated using a Jatropha-based biorefinery system converting Jatropha seed into biodiesel, glycerol and cake, as a case study. The biodiesel produced can achieve 53% emission cut, while glycerol and cake can achieve an emission cut by 57% by displacing similar functionality fossil based products. © 2014 Elsevier Ltd. All rights reserved.
Sadhukhan J (2012) Multiscale simulation for high efficiency biodiesel process intensification, Computer Aided Chemical Engineering 30 pp. 1023-1027 Elsevier
Design of highly efficient multifunctional reaction processes for energy production is one of the main focus areas of Chemical Engineering. This article presents multiscale simulation frameworks for heterogeneously catalyzed reactors wherein numerous synthesis steps are integrated for high efficiency biodiesel production. The goal is the modeling of transport-adsorption-reaction-desorption phenomena through catalytic porous networks for efficient diffusion, reactions of desired pathways and elimination of side reactions and waste formation. Building upon exciting ongoing EPSRC funded research activities on 'Designer catalyst for high efficiency biodiesel production', this work proposes a simulation method to refine micro-meso porous kinetic and diffusive parameters to converge with the experimental results and for biodiesel synthesis in continuous oscillatory baffle reactor (OBR) from non-edible oils. © 2012 Elsevier B.V.
Sadhukhan J, Zhang N, Zhu XX, Smith R (2004) Value analysis of industrial systems, AIChE Annual Meeting, Conference Proceedings pp. 7327-7334
The development of a generalized strategy for modeling and integration of an overall system, for detailed economic analysis of industrial systems, is described. Economic analysis of a system establishes the economic analysis of streams and processes with respect to the current system operation, network configuration, and market situation. An overall integration is developed to capture the impacts of real plant operations and the effects of network interactions in the detailed economic analysis of complex systems. The approach for economic analysis of a system is simple and provides a transparent and complete set of economic values for all basic components and correlates these values with the overall system economic margin.
Martinez-Hernandez E, Campbell G, Sadhukhan J (2012) Economic Value and Environmental Impact analysis tool for sustainable biorefinery design, Computer Aided Chemical Engineering 30 pp. 11-15
The selections of product portfolios, processing routes and the combination of technologies to obtain a sustainable biorefinery design according to economic and environmental criteria represent a challenge to process engineering. The aim of this research is to generate a simple but yet robust methodology that assists the process engineers to understand the environmental and economic behaviour of biorefinery systems. The novel Economic Value and Environmental Impact analysis (EVEI) methodology is presented in this paper. EVEI analysis is a tool that emerges from the combination of the value analysis method for the evaluation of economic potential and environmental footprinting for impact analysis. A quick illustration of the methodology in providing insights into the performances of a process network is given by taking a bioethanol plant as case study. The applicability to analyse biorefinery systems for selection of process pathway alternatives is demonstrated by using a Jatropha-based biorefinery case study. The systematisation of the methodology allowed its implementation and integration into a Computer Aided Process Engineering (CAPE) tool in the well known Excel® environment using the built-in VBA facility. This will accelerate the design process allowing focus on the analysis of results and devising alternatives from highly complex integrated process schemes. © 2012 Elsevier B.V.
Martinez-Hernandez E, Campbell GM, Sadhukhan J (2013) Jatropha-based biorefinery integrating chemical and thermochemical platforms for the co-production of biofuel, bioenergy and chemicals, Sustainable Engineering Forum 2013 - Core Programming Area at the 2013 AIChE Annual Meeting: Global Challenges for Engineering a Sustainable Future pp. 637-638
Sadhukhan J (2014) Distributed and micro-generation from biogas and agricultural application of sewage sludge: Comparative environmental performance analysis using life cycle approaches, Applied Energy 122 pp. 196-206
The Feed-In-Tariff scheme in the UK has generated attractive economics in the investment for anaerobic digestion (AD) to convert sewage sludge into biogas and digested sludge for energy and agricultural applications, respectively. The biogas is a source of biomethane to replace natural gas in the gas grid system. Biogas can be utilised to generate combined heat and power (CHP) on-site, at household micro and distributed or community scales. These biogas CHP generation options can replace the equivalent natural gas based CHP generation options. Digested sludge can be transformed into fertiliser for agricultural application replacing inorganic N:P:K fertiliser. Biogas and digested matter yields are inter-dependent: when one increases, the other decreases. Hence, these various options need to be assessed for avoided life cycle impact potentials, to understand where greatest savings lie and in order to rank these options for informed decision making by water industries. To fill a gap in the information available to industry dealing with wastewater, the avoided emissions by various AD based technologies, in primary impact potentials that make a difference between various systems, have been provided in this paper.1m3 biogas can save 0.92m3 natural gas. An average UK household (with a demand of 2kWe) requires 180,000MJ or 5000Nm3 or 4.76t biogas per year, from 15.87t sewage sludge processed through AD. The proton exchange membrane fuel cell (PEM FC) is suitable for building micro-generations; micro gas turbine (Micro GT), solid oxide fuel cell (SOFC) and SOFC-GT hybrid are suitable for distributed generations upto 500kWe and occasionally over 500kWe; engine and ignition engine above 1MWe. These CHP technologies can be ranked from the lowest to the highest impacts per unit energy production: PEM FC is the environmentally most benign option, followed by SOFC, SOFC-GT, Engine or Micro GT and Ignition engine (with the highest impact potential), respectively. In terms of avoided global warming, acidification and photochemical ozone creation potentials, compared to equivalent natural gas based systems, the biogas based PEM FC micro-generation and Micro GT distributed systems achieve the greatest avoided emissions with the most cost-effectiveness. Application of digested sludge as fertiliser has more toxicity impacts, however, has greater avoided emissions in acidification and photochemical ozone creation potentials on the basis of inorg
Kapil A, Bhat SA, Sadhukhan J (2010) Dynamic Simulation of Sorption Enhanced Reaction Processes for Biodiesel Production, INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH 49 (5) pp. 2326-2335 AMER CHEMICAL SOC
Sadhukhan J, Martinez-Hernandez E, Murphy R, Ng D, Hassim M, Ng K, Kim W, Jaye I, Leung M, Hang P, Andiappan V (2017) Role of Bioenergy, Biorefinery and Bioeconomy in Sustainable Development: Strategic Pathways for Malaysia, Renewable & Sustainable Energy Reviews 81 (Part 2) pp. 1966-1987 Elsevier
Malaysia has a plethora of biomass that can be utilized in a sustainable manner to produce bio-products for circular green economy. At the 15th Conference of Parties in Copenhagen, Malaysia stated to voluntarily reduce its emissions intensity of gross domestic product by upto 40% by 2020 from 2005 level. Natural resources e.g. forestry and agricultural resources will attribute in achieving these goals. This paper investigates optimum bio-based systems, such as bioenergy and biorefinery, and their prospects in sustainable development in Malaysia, while analyzing comparable cases globally. Palm oil industry will continue to play a major role in deriving products and contributing to gross national income in Malaysia. Based on the current processing capacity, one tonne of crude palm oil (CPO) production is associated with nine tonnes of biomass generation. Local businesses tend to focus on products with low-risk that enjoy subsidies, e.g. Feed-in-Tariff, such as bioenergy, biogas, etc. CPO biomass is utilized to produce biogas, pellets, dried long fibre and bio-fertilizer and recycle water. It is envisaged that co-production of bio-based products, food and pharmaceutical ingredients, fine, specialty and platform chemicals, polymers, alongside biofuel and bioenergy from biomass is possible to achieve overall sustainability by the replacement of fossil resources. Inception of process integration gives prominent innovative biorefinery configurations, an example demonstrated recently, via extraction of recyclable, metal, high value chemical (levulinic acid), fuel, electricity and bio-fertilizer from municipal solid waste or urban waste. Levulinic acid yield by only 5 weight% of waste feedstock gives 1.5 fold increase in profitability and eliminates the need for subsidies such as gate fees paid by local authority to waste processor. Unsustainable practices include consumable food wastage, end-of-pipe cleaning and linear economy that must be replaced by sustainable production and consumption, source segregation and process integration, and product longevity and circular economy.
Black M, Sadhukhan J, Day K, Drage G, Murphy R (2016) Developing database criteria for the assessment of biomass supply chains for biorefinery development, Chemical Engineering Research and Design pp. 253-262 Elsevier
The sustainable biorefinery will only be realised with a focus on optimal combinations of feedstock-process technologies-products. For many years, industry has been looking to add value to the by-products of commercial agriculture, forestry and processing. More recently, as concerns about climate change have increased around the globe, the use of biomass as a carbon saving feedstock (compared to fossil feedstock) has led to the implementation of policies to encourage its use for bioenergy, biofuels and bio-based products. As biomass conversion technologies become reality at the commercial scale for a range of diverse end products, the need to establish bespoke biomass supply chains also becomes a reality and industrial developers will face many business-critical decisions on the sourcing of biomass and location of conversion plants (biorefineries). The research presented here, aims to address these issues through the development of a comprehensive database to aid biomass sourcing and conversion decision-making. The database covers origin, logistics, technical suitability (in this case for a proprietary organosolv pre-treatment process) and policy and other risk attributes of the system. The development of key criteria required by the business community to develop biomass supply chains for specific requirements is discussed.
Ng K, Head I, Premier G, Scott K, Yu E, Lloyd J, Sadhukhan J (2016) A Multilevel Sustainability Analysis of Zinc Recovery from Wastes, Resources, Conservation & Recycling 113 pp. 88-105 Elsevier
As waste generation increases with increasing population, regulations become stricter to control and mitigate environmental emissions of substances, e.g. heavy metals: zinc and copper. Recovering these resources from wastes is the key interest of industries. The objective of this paper is the sustainability and feasibility evaluations of zinc recovery from waste streams. Sustainability and feasibility of a resource recovery strategy from wastes in a circular economy are governed by avoided environmental impacts and cost-effective transformation of an environmental contaminant into a valuable resource, e.g. as a coproduct by making use of an existing infrastructure as much as possible. This study, for the first time, gives a comprehensive overview of secondary sources and processes of recovering zinc, its stock analysis by country, regional and global divisions by a Sankey diagram, policies to regulate zinc emissions and avoided environmental impacts by zinc recovery. Two representative cases are further investigated for economic feasibility analysis of zinc recovery from 1) steelmaking dust and (2) municipal solid waste (MSW). The amount and value of zinc that can be generated from dust emitted from various steelmaking technologies are estimated. Additional revenues for the steelmaking industrial sector (with electric arc furnace), at the plant, national (UK), regional (EU) and global levels are 11, 12, 169 and 1670 million tonne/y, or 19-143, 20-157, 287-2203 and 2834-21740 million ¬/y, respectively. The second case study entails an integrated mechanical biological treatment (MBT) system of MSW consisting of metal recovery technologies, anaerobic digestion, refuse derived fuel (RDF) incineration and combined heat and power (CHP) generation. An effective economic value analysis methodology has been adopted to analyse the techno-economic feasibility of the integrated MBT system. The value analysis shows that an additional economic margin of 500 ¬ can be generated from the recovery of 1 tonne of zinc in the integrated MBT system enhancing its overall economic margin by 9%.
This paper, for the first time, reports integrated conceptual MBCT/biorefinery systems for unlocking the value of organics in municipal solid waste (MSW) through the production of levulinic acid (LA by 5wt%) that increases the economic margin by 110-150%. After mechanical separation recovering recyclables, metals (iron, aluminium, copper) and refuse derived fuel (RDF), lignocelluloses from remaining MSW are extracted by supercritical-water for chemical valorisation, comprising hydrolysis in 2wt% dilute H2SO4 catalyst producing LA, furfural, formic acid (FA), via C5/C6 sugar extraction, in plug flow (210?230°C, 25bar, 12s) and continuous stirred tank (195?215°C, 14bar, 20mins) reactors; char separation and LA extraction/purification by methyl isobutyl ketone solvent; acid/solvent and by-product recovery. The by-product and pulping effluents are anaerobically digested into biogas and fertiliser. Produced biogas(6.4MWh/t), RDF(5.4MWh/t), char(4.5MWh/t) are combusted, heat recovered into steam generation in boiler (efficiency:80%); on-site heat/steam demand is met; balance of steam is expanded into electricity in steam turbines (efficiency:35%).
Miah Jamal, Sadhukhan Jhuma, Griffiths A, McNeill R, Halvorson S, Schenker U, Espinoza-Orias N. D., Morse S, Yang A (2017) A framework for increasing the availability of life cycle inventory data based on the role of multinational companies, International Journal of Life Cycle Assessment 23 pp. 1744-1760 Springer Verlag
Purpose
The aim of the paper is to assesses the role and effectiveness of a proposed novel strategy for Life Cycle Inventory (LCI) data collection in the food sector and associated supply chains. The study represents one of the first of its type and provides answers to some of the key questions regarding the data collection process developed, managed and implemented by a multinational food company across the supply chain.
Methods
An integrated LCI data collection process for confectionery products was developed and implemented by Nestlé, a multinational food company. Some of the key features includes: (1) management and implementation by a multinational food company, (2) types of roles to manage, provide and facilitate data exchange, (3) procedures to identify key products, suppliers and customers, (4) LCI questionnaire and cover letter, and (5) data quality management based on the pedigree matrix. Overall, the combined features in an integrated framework provides a new way of thinking about the collection of LCI data from the perspective of a multinational food company.
Results
The integrated LCI collection framework spanned across five months and resulted in 87 new LCI datasets for confectionery products from raw material, primary resource use, emission and waste release data collected from suppliers across 19 countries. The data collected was found to be of medium-to-high quality compared with secondary data. However, for retailers and waste service companies only partially completed questionnaires were returned. Some of the key challenges encountered during the collection and creation of data included: lack of experience, identifying key actors, communication and technical language, commercial compromise, confidentiality protection, and complexity of multi-tiered supplier systems. A range of recommendations are proposed to reconcile these challenges which include: standardisation of environmental data from suppliers, concise and targeted LCI questionnaires, and visualising complexity through drawings.
Conclusions
The integrated LCI data collection process and strategy has demonstrated the potential role of a multinational company to quickly engage and act as a strong enabler to unlock latent data for various aspects of the confectionery supply chain. Overall, it is recommended that the research findings serve as the foundations to transition towards a standardised procedure which can practically guide other multinational companies to considerably increase the availability of LCI data.
Miah J, Griffiths A, McNeill R, Halvorson S, Schenker U, Espinoza-Orias N, Morse S, Yang A, Sadhukhan J (2017) Environmental management of confectionery products: Life cycle impacts and improvement strategies, Journal of Cleaner Production 177 pp. 732-751 Elsevier
This paper presents the first environmental life cycle analysis for a range of different confectionery products. A proposed Life Cycle Assessment (LCA) approach and multi-criteria decision analysis (MCDA) was developed to characterise and identify the environmental profiles and hotspots for five different confectionery products; milk chocolate, dark chocolate, sugar, milk chocolate biscuit and milk-based products. The environmental impact categories are based on Nestle's EcodEX LCA tool which includes Global Warming Potential (GWP), Abiotic Depletion Potential (ADP), ecosystems quality, and two new indicators previously not considered such as land use and water depletion. Overall, it was found that sugar confectionery had the lowest aggregated environmental impact compared to dark chocolate confectionery which had the highest, primarily due to ingredients. As such, nine key ingredients were identified across the five confectionery products which are recommended for confectionery manufacturers to prioritise e.g. sugar, glucose, starch, milk powder, cocoa butter, cocoa liquor, milk liquid, wheat flour and palm oil. Furthermore, the general environmental hotspots were found to occur at the following life cycle stages: raw materials, factory, and packaging. An analysis of five improvement strategies (e.g. alternative raw materials, packaging materials, renewable energy, product reformulations, and zero waste to landfill) showed both positive and negative environmental impact reduction is possible from cradle-to-grave, especially renewable energy. Surprisingly, the role of product reformulations was found to achieve moderate-to-low environmental reductions with waste reductions having low impacts. The majority of reductions was found to be achieved by focusing on sourcing raw materials with lower environmental impacts, product reformulations, and reducing waste generating an aggregated environmental reduction of 46%. Overall, this research provides many insights of the environmental impacts for a range of different confectionery products, especially how actors across the confectionery supply chain can improve the environmental sustainability performance. It is expected the findings from this research will serve as a base for future improvements, research and policies for confectionery manufacturers, supply chain actors, policy makers, and research institutes towards an environmentally sustainable confectionery industry.
Gear Matthew, Sadhukhan Jhuma, Thorpe Rex, Clift Roland, Seville Jonathan, Keast M (2018) A life cycle assessment data analysis toolkit for the design of novel processes - A case study for a thermal cracking process for mixed plastic waste, Journal of Cleaner Production 180 pp. 735-747 Elsevier
The earlier in the development of a process a design change is made, the lower the cost and the higher the impact on the final performance. This applies equally to environmental and technical performance, but in practice the environmental aspects often receive less attention. To maximise sustainability, it is important to review all of these aspects through each stage, not just after the design. Tools that integrate environmental goals into the design process would enable the design of more environmentally friendly processes at a lower cost. This paper brings together approaches based on Life Cycle Assessment (LCA) including comparisons of design changes, hotspot analysis, identification of key impact categories, environmental break-even analysis, and decision analysis using ternary diagrams that give detailed guidance for design while not requiring high quality data. The tools include hotspot analysis to reveal which unit operations dominate the impacts and therefore should be the focus of further detailed process development. This approach enables the best variants to be identified so that the basic design can be improved to reduce all significant environmental impacts. The tools are illustrated by a case study on the development of a novel process with several variants: thermal cracking of mixed plastic waste to produce a heavy hydrocarbon product that can displace crude oil, naphtha, or refinery wax or be used as a fuel. The results justified continuing with the development by confirming that the novel process is likely to be a better environmental option than landfill or incineration. The general approach embodied in the toolkit should be applicable in the development of any new process, particularly one producing multiple products.
Shemfe Mobolaji, Gadkari Siddharth, Yu Eileen, Rasul Shahid, Scott Keith, Head Ian M., Gu Sai, Sadhukhan Jhuma (2018) Life cycle, techno-economic and dynamic simulation assessment of bioelectrochemical systems: A case of formic acid synthesis, Bioresource Technology 255 pp. 39-49 Elsevier
A novel framework, integrating dynamic simulation (DS), life cycle assessment (LCA) and techno-economic assessment (TEA) of a bioelectrochemical system (BES), has been developed to study for the first time wastewater treatment by removal of chemical oxygen demand (COD) by oxidation in anode and thereby harvesting electron and proton for carbon dioxide reduction reaction or reuse to produce products in cathode. Increases in initial COD and applied potential increase COD removal and production (in this case formic acid) rates. DS correlations are used in LCA and TEA for holistic performance analyses. The cost of production of HCOOH is ¬0.015?0.005/g?1 for its production rate of 0.094?0.26/kg/yr?1 and a COD removal rate of 0.038?0.106/kg/yr?1. The life cycle (LC) benefits by avoiding fossil-based formic acid production (93%) and electricity for wastewater treatment (12%) outweigh LC costs of operation and assemblage of BES (?5%), giving a net 61MJkg?1 HCOOH saving.
Gadkari Siddharth, Gu Sai, Sadhukhan Jhuma (2018) Towards automated design of bioelectrochemical
systems: A comprehensive review of mathematical
models,
Chemical Engineering Journal 343 pp. 303-316 Elsevier
This review presents the developments in the mathematical models for various
bioelectrochemical systems. A number of modeling approaches starting
with the simple description of biological and electrochemical processes in
terms of ordinary differential equations to very detailed 2D and 3D models
that study the spatial distribution of substrates and biomass, have been
developed to study BES performance. Additionally, mathematical models
focused on studying a particular process such as ion diffusion through membrane
and new modeling approaches such as artifcial intelligence methods,
cellular network models, etc., have also been described. While most mathematical
models are still focused on performance studies and optimization of
microbial fuel cells, new models to study other BESs such as microbial electrolysis
cell, microbial electrosynthesis and microbial desalination cell have
also been reported and discussed in this review.
Shemfe Mobolaji, Gadkari Siddharth, Yu E, Rasul S, Scott K, Head I, Gu Sai, Sadhukhan Jhuma (2018) Life cycle, techno-economic and dynamic simulation assessment of bioelectrochemical systems: A case of formic acid synthesis, Bioresource Technology 255 pp. 39-49 Elsevier
A novel framework integrating dynamic simulation (DS), life cycle assessment (LCA) and techno-economic assessment (TEA) of bioelectrochemical system (BES) has been developed to study for the first time wastewater treatment by removal of chemical oxygen demand (COD) by oxidation in anode and thereby harvesting electron and proton for carbon dioxide reduction reaction or reuse to produce products in cathode. Increases in initial COD and applied potential increase COD removal and production (in this case formic acid) rates. DS correlations are used in LCA and TEA for holistic performance analyses. The cost of production of HCOOH is ¬0.015?0.005g?1 for its production rate of 0.094?0.26kgyr?1 and a COD removal rate of 0.038?0.106kgyr?1. The life cycle (LC) benefits by avoiding fossil-based formic acid production (93%) and electricity for wastewater treatment (12%) outweigh LC costs of operation and assemblage of BES (?5%), giving a net 61MJkg-1HCOOH saving.
Jaye I, Sadhukhan J, Murphy R (2018) Integrated Assessment of Palm Oil Mill Residues to
Sustainable Electricity System (POMR-SES): A Case Study
from Peninsular Malaysia,
IOP Conference Series: Materials Science and Engineering 358 012002 Institute of Physics
Generating electricity from biomass are undeniably gives huge advantages to the
energy security, environmental protection and the social development. Nevertheless, it always
been negatively claimed as not economically competitive as compared to the conventional
electricity generation system using fossil fuel. Due to the unfair subsidies given to renewable
energy based fuel and the maturity of conventional electricity generation system, the
commercialization of this system is rather discouraging. The uniqueness of the chemical and
physical properties of the biomass and the functionality of the system are fully depending on
the availability of the biomass resources, the capital expenditure of the system is relatively
expensive. To remain competitive, biomass based system must be developed in their most
economical form. Therefore the justification of the economies of scale of such system is
become essential. This study will provide a comprehensive review of process to select an
appropriate size for electricity generation plant from palm oil mill (POM) residues through the
combustion of an empty fruit bunch (EFB) and biogas from the anaerobic digestion of palm oil
mill effluent (POME) in Peninsular Malaysia using a mathematical model and simulation using
ASPEN Plus software package. The system operated at 4 MW capacity is expected to provide
a return on investment (ROI) of 20% with a payback period of 6.5 years. It is notably agreed
that the correct selection of generation plant size will have a significant impact on overall
economic and environmental feasibility of the system.
Global consumption for confectionery products are growing and is exerting enormous pressures on confectionery supply chains across the world to efficiently utilise natural resources towards becoming environmentally sustainable. However, there are a disparate range of studies investigating the environmental impacts of confectionery products, and more importantly how to improve environmental sustainability performance. In this thesis, the aim was to improve knowledge of opportunities for reducing environmental impact in confectionery manufacturing ? from factory to supply chain ? by developing methodological tools based on heat integration and Life Cycle Assessment (LCA). A range of novel methodologies were developed to advance heat integration and LCA knowledge, including (1) a heat integration framework combining direct and indirect heat exchange from zonal to multiple zones, possibly incorporating heat pump technology to enhance low grade heat recovery; (2) methodologies for systematically improving Life Cycle Inventory (LCI) data based on the role of multinational companies and for conducting effective LCA for confectionery products; and (3) a methodology to assess and quantify the environmental life cycle impacts of multi-product food factories. These methodologies have been applied at a multi-product confectionery factory, which has revealed significant findings: (1) combining direct and indirect heat integration from zonal to multiple zones can reduce factory energy by 4.04?6.05%, (2) heat pump technology can reduce factory energy by up to 29.2% but imposes design complexity and long economic paybacks up to 6.62 years, (3) fine bakery ware products on average was found to have the highest aggregated environmental life cycle impacts (higher than chocolate products by 7.1%, milk-based products by 18%, and sugar by 51.9%), and (4) combined improvement strategies of 50% energy reduction with 100% renewable energy, zero food waste to landfill (inc. 50% food waste reduction), and raw material changes to lower impacts can potentially reduce: Global Warming Potential by 65.82%, water depletion by 43.02%, abiotic depletion potential by 20.66%, land use by 17.45% and ecosystem quality by 7.24%. Overall, this research has culminated in several contributions to knowledge which substantially increases understanding of how to improve the environmental sustainability of confectionery manufacturing across the product, factory and supply chain level. The research will serve as a guide for future improvements, research and policies of confectionery manufacturers, supply chain actors, policy makers, and research institutes.
Bioelectrochemical systems (BESs) have been catalogued as a technological solution to three pressing global challenges: environmental pollution, resource scarcity, and freshwater scarcity. This study explores the social risks along the supply chain of requisite components of BESs for two functionalities: (i) copper recovery from spent lees and (ii) formic acid production via CO2 reduction, based on the UK?s trade policy. The methodology employed in this study is based on the UNEP/SETAC guidelines for social life-cycle assessment (S-LCA) of products. Relevant trade data from UN COMTRADE database and generic social data from New Earth?s social hotspot database were compiled for the S-LCA. The results revealed that about 75% of the components are imported from the European Union. However, the social risks were found to vary regardless of the magnitude or country of imports. ?Labour and Decent Work? was identified as the most critical impact category across all countries of imports, while the import of copper showed relatively higher risk than other components. The study concludes that BESs are a promising sustainable technology for resource recovery from wastewater. Nevertheless, it is recommended that further research efforts should concentrate on stakeholder engagement in order to fully grasp the potential social risks.
It is well accepted that the technical, financial and environmental performance of a chemical process is largely determined during design. Therefore, the development of tools that integrate environmental considerations would enable the design of more environmentally friendly processes at a lower cost. This research investigates how Life Cycle Assessment (LCA) can be applied at any stage in the design process to produce useful information for design, not just after the plant is operating, which is the norm for LCA. The tools have been applied to the development of a novel process (the RT7000): thermal cracking of mixed plastic waste to produce several hydrocarbon products with the potential to displace crude oil, naphtha, or refinery wax or be used as a fuel.

To allow LCA to guide the design process, a toolkit methodology was developed including comparisons of design changes, hotspot analysis, identification of key impact categories, environmental break-even analysis, and decision analysis using ternary diagrams. The results of applying these tools justified continuing with the development by confirming that the novel process is likely to be a better environmental option than landfill or incineration.

At the later stages of design, advanced tools such as process simulations become attractive and allow a more accurate estimation of material and energy flows. A simulation of the RT7000 in Aspen Plus® was developed that provided data for a wide range of feed compositions. The RT7000 continued to have lower environmental impact to incineration offering a saving equivalent to 969-1305 kgCO2/tonne plastic processed. It was also ascertained that variation in feed composition does influence environmental performance, but not enough to affect the outcomes of decision making.

The general approaches used in this work to assess the RT7000 should be applicable to the development of any new process. Benefits and insights similar to those obtained in the case study can realistically be expected when these methodologies are applied to any new processes. Therefore the results have been published in the Journal of Cleaner Production (Gear et al., 2018)