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A Systems Approach to Promoting Sustainable Bioeconomy through International Development of Novel Biorefinery System Concepts


At present, most industries are heavily relying on fossil fuels and this has caused severe damage to the environment. Transitioning from a fossil based economy to a more sustainable, renewable and circular economy is envisaged and exigent, however this is not straightforward as there are various challenges that need to be addressed such as the availability of renewable feedstock, robustness of the conversion and pollution mitigation technologies, and sustainability performance of the whole system.

We need to undertake a more holistic and unified approach, in view of achieving a more circular economy and net zero targets. This can only be realised through a systems approach (i.e. integrated and multidisciplinary collaboration) that incorporates innovative engineering solutions; developing and accelerating the uptake of transformative technologies in the industry; and policy harmonisation.

This research project will focus on developing novel biorefinery system design that is highly integrated, flexible and robust for the production of fuels, chemicals, hydrogen and polymers. Biomass is regarded as a carbon-neutral feedstock and can potentially achieve negative carbon emissions if carbon capture, utilisation and storage (CCUS) facilities are embedded within the biorefinery system.

This research will explore one or more of the following areas:

• Sustainable aviation fuel production

• Chemical, hydrogen, methanol, Fischer-Tropsch liquid production

• Combined heat and power (CHP)

• Thermochemical and biochemical conversion of biomass

• CCUS pathways

• Centralised and decentralised configurations

Chemical engineering principles, process integration and intensification techniques are needed in designing the biorefinery systems in order to achieve maximum resource efficiency and minimum environmental impact by recovering by-product and waste streams into value-added products.

What would you expect from this project?

• Computational modelling: This project will require simulation modelling and optimisation techniques using software such as Aspen Plus, Matlab and GAMS, and will also involve software development using Python.

• Sustainability assessment: This research will involve rigorous sustainability assessment including techno-economic analysis and environmental life cycle assessment (LCA). LCA software such as SimaPro is required.

• International collaboration: In addition to the core engineering research study, this research will also involve great learning opportunities working with international collaborators from Malaysia, Thailand, Mexico and Brazil in view of promoting sustainability and circular economy practices in the developing countries.

You will have the opportunity to learn the policy aspects of these countries, engage with relevant stakeholders and integrate systems thinking into your study.

Applicants should have received a First or Upper Second Class honours degree in Chemical Engineering, Environmental Engineering, Chemistry or a similar discipline. Applicants should be highly motivated, able to work independently and in a team, and have good written and verbal communication skills.


Previous studies related to biorefinery systems:

1. Yeoh, L., Ng, K.S., 2022. Future prospects of spent coffee ground valorisation using a biorefinery approach. Resour Conserv Recycl. 179: 106123.

2. Ng, K.S., Farooq, D., Yang, A., 2021. Global biorenewable development strategies for sustainable aviation fuel production. Renew. Sustain. Energy Rev. 150: 111502.

3. Ng, K.S., Martinez-Hernandez, E., 2020. Techno-economic assessment of an integrated bio-oil steam reforming and hydrodeoxygenation system for polygeneration of hydrogen, chemicals, and combined heat and power production, in Towards Sustainable Chemical Processes, J. Ren, Y. Wang, and C. He, (Ed.), p. 69-98, Elsevier.

4. Martinez Hernandez, E., Ng, K.S., 2018. Design of biorefinery systems for conversion of corn stover into biofuels using a biorefinery engineering framework. Clean Technol Envir. 20(7): 1501-1514.

5. Sadhukhan, J., Ng, K.S., Martinez Hernandez, E., 2014. Biorefineries and chemical processes: design, integration and sustainability analysis, Wiley. ISBN: 9781119990864.

6. Ng, K.S., Sadhukhan, J., 2011. Techno-economic performance analysis of bio-oil based Fischer-Tropsch and CHP synthesis platform. Biomass Bioenergy, 35 (7): 3218-3234.

7. Ng, K.S., Sadhukhan, J., 2011. Process integration and economic analysis of bio-oil platform for the production of methanol and combined heat and power. Biomass Bioenergy, 35 (3): 1153-1169. Websites: SYNERGORS Project: CRES Society:

How to apply

If you are interested in applying for the above PhD topic please follow the steps below:

  1. Contact the supervisor by email or phone to discuss your interest and find out if you woold be suitable. Supervisor details can be found on this topic page. The supervisor will guide you in developing the topic-specific research proposal, which will form part of your application.
  2. Click on the 'Apply here' button on this page and you will be taken to the relevant PhD course page, where you can apply using an online application.
  3. Complete the online application indicating your selected supervisor and include the research proposal for the topic you have selected.

Good luck!

This is a self funded topic

Brunel offers a number of funding options to research students that help cover the cost of their tuition fees, contribute to living expenses or both. See more information here: The UK Government is also offering Doctoral Student Loans for eligible students, and there is some funding available through the Research Councils. Many of our international students benefit from funding provided by their governments or employers. Brunel alumni enjoy tuition fee discounts of 15%.

Meet the Supervisor(s)

Kok Siew Ng - Dr Kok Siew Ng is a Lecturer (Assistant Professor) in Chemical Engineering at Brunel University London. He joined Brunel in March 2022 after the completion of his 4-year independent fellowship at University of Oxford. He is also currently the Co-Investigator and Coordinator of the Oxford Agile project (Sprint 2) – a university-wide initiative focusing on tackling various environmental challenges using an interdisciplinary approach, funded through the £10 million NERC Changing the Environment programme. The sprint project aims to develop strategies for determining the best regional combination of nutrient recovery and utilisation options for both economic viability and environmental benefits. Prior to joining Brunel, Kok Siew was a UKRI/NERC Industrial Innovation (Rutherford) Research Fellow and Lecturer in Chemical Engineering at the Department of Engineering Science, University of Oxford, from 2018 to 2022. During his time in Oxford, he was a Principal Investigator of the SYNERGORS project 'A systems approach to synergistic utilisation of secondary organic streams' (£0.5 million), funded by NERC. The project aimed to explore novel approaches to addressing challenges in organic waste management and achieving circular economy.  He completed his MEng Chemical Engineering with Chemistry (First Class Honours) in 2008, and later gained his PhD in 2011 from the Centre for Process Integration (CPI), The University of Manchester. After completing his PhD, he joined Process Integration Limited (PIL) as a consultant and later took up a position as a Postdoctoral Research Fellow at the Centre for Environment and Sustainability (CES), University of Surrey.  Kok Siew is a chemical engineer by training with extensive research and industrial consultancy experience in systems engineering, process integration, techno-economic analysis and environmental life cycle assessment (LCA). His research vision is to develop novel and sustainable solutions from a systems engineering perspective, to facilitate the transition of the chemical, energy and waste industries from a fossil-based, linear system to one that is fundamentally sustainable by using renewables as the mainstream resources and by fully embracing circular economy principles. He has contributed to more than 10 UK and international projects funded by NERC, Innovate UK, EU FP7, Royal Academy of Engineering and Newton Fund. His research is significant in terms of addressing global challenges in the 21st century, aligned with the UN SDG 7 and 12, the UK Industrial Strategy, and international ambitions to achieving circular economy and net-zero target. Kok Siew has published more than 30 articles including journals, book chapters and magazine article, and have co-authored an advanced textbook “Biorefineries and Chemical Processes: Design, Integration and Sustainability Analysis”. His work related to decarbonisation of energy systems has been recognised by the IChemE Junior Moulton Medal award (best publication) in 2011. Furthermore, Kok Siew has been nominated for the University of Oxford Vice-Chancellor's Environmental Sustainability Staff Award in 2022 for his contribution in actively promoting environmental sustainability through his research vision, which develops sustainable solutions from a systems engineering perspective. He is an Editorial Board Member of Resources, Conservation & Recycling Advances (RCR Advances) journal and also a reviewer for French ANR and UKRI/EPSRC proposals. Kok Siew is enthusiastic in establishing international collaboration with researchers from multidisciplinary background. He has been working closely with international academic and industrial organisations in the UK, Europe, China and South East Asia. He has organised and participated in a number of British Council/Newton Fund workshops in Malaysia, Mexico, Brazil, Kazakhstan and China, and attended the Royal Academy of Engineering Frontiers of Engineering for Development Symposium “From feeding people to nourishing people”. He has a long-term ambition in influencing resources and waste management practices in developing countries towards sustainable development. Kok Siew is the Founder and President of the Society of Circular, Regenerative and Sustainable Systems (CRES). The aims of CRES society (knowledge exchange) and SYNERGORS consortium (research) are to promote and strengthen cross-disciplinary and cross-sectoral collaboration between the UK and international organisations in systems thinking and circular economy. His ambition in international development together with the objectives of SYNERGORS and CRES are well aligned with the UK Industrial Strategy in enhancing resource efficiency and mitigating pollution and waste materials, while achieving a sustainable industrial growth and a more resilient economy at global level. Awards and Achievements -
  • Nominated for the University of Oxford Vice-Chancellor's Environmental Sustainability Staff Award, 2022.
  • Best Oral Presentation Award, Newton-Al-Farabi UK-Kazakhstan workshop “Low-carbon Future: Efficient Management of Resources and Energy”, 26-28 September 2016, Astana, Kazakhstan.
  • IChemE Junior Moulton Medal for the best publication, 2011 - “Ng, K.S., Lopez, Y., Campbell, G.M., Sadhukhan, J., 2010. Heat integration and analysis of decarbonised IGCC sites. Chem Eng Res Des., 88 (2): 170-188.”
  • PhD Scholarships (2008-2011): Overseas Research Scholarship (ORS), Manchester Alumni Funds, Process Integration Research Consortium (PIRC) Research Funds, School of Chemical Engineering and Analytical Science Scholarship
  • MEng Chemical Engineering with Chemistry Specialist Subject Course Prize (ranked 1st in the cohort), 2008, The University of Manchester.