Dr Mark Walker

Dr Mark Walker

Lecturer in Energy Engineering

Faculty and Department

  • Faculty of Science and Engineering
  • Department of Engineering

Qualifications

  • MEng (Durham University)
  • PhD (University of Southampton)

Summary

I graduated with a MEng in Engineering (Mechanical) from the University of Durham in 2004 I went on to study for my PhD at the University of Southampton with the project title "Development of a Mesh Bioreactor for the Anaerobic Digestion of Biodegradable Municipal Waste".

In the subsequent decade I have continued to specialise in anaerobic digestion and biogas systems applied as a bioenergy technology and to treat both organic waste and wastewater. Increasingly my research has broadened to incorporate more general issues surrounding energy system integration and decarbonisation, industrial and environmental biotechnology and the bio- and circular economies.

See the research tab for more details surrounding my work, or feel free to contact me if you are interesting in working with me.

Undergraduate

I am Programme Director for the MSc Energy Engineering.

Recent outputs

View more outputs

Journal Article

A techno-economic assessment of implementing power-to-gas systems based on biomethanation in an operating waste water treatment plant

Michailos, S., Walker, M., Moody, A., Poggio, D., & Pourkashanian, M. (2021). A techno-economic assessment of implementing power-to-gas systems based on biomethanation in an operating waste water treatment plant. Journal of Environmental Chemical Engineering, 9(1), https://doi.org/10.1016/j.jece.2020.104735

Biomethane production using an integrated anaerobic digestion, gasification and CO2 biomethanation process in a real waste water treatment plant: A techno-economic assessment

Michailos, S., Walker, M., Moody, A., Poggio, D., & Pourkashanian, M. (2020). Biomethane production using an integrated anaerobic digestion, gasification and CO2 biomethanation process in a real waste water treatment plant: A techno-economic assessment. Energy Conversion and Management, 209, https://doi.org/10.1016/j.enconman.2020.112663

Assessment of micro-scale anaerobic digestion for management of urban organic waste: A case study in London, UK

Walker, M., Theaker, H., Yaman, R., Poggio, D., Nimmo, W., Bywater, A., …Pourkashanian, M. (2017). Assessment of micro-scale anaerobic digestion for management of urban organic waste: A case study in London, UK. Waste Management, 61, 258-268. https://doi.org/10.1016/j.wasman.2017.01.036

Modelling the anaerobic digestion of solid organic waste – Substrate characterisation method for ADM1 using a combined biochemical and kinetic parameter estimation approach

Poggio, D., Walker, M., Nimmo, W., Ma, L., & Pourkashanian, M. (2016). Modelling the anaerobic digestion of solid organic waste – Substrate characterisation method for ADM1 using a combined biochemical and kinetic parameter estimation approach. Waste Management, 53, 40-54. https://doi.org/10.1016/j.wasman.2016.04.024

Assessment and parameter identification of simplified models to describe the kinetics of semi-continuous biomethane production from anaerobic digestion of green and food waste

Owhondah, R. O., Walker, M., Ma, L., Nimmo, B., Ingham, D. B., Poggio, D., & Pourkashanian, M. (2016). Assessment and parameter identification of simplified models to describe the kinetics of semi-continuous biomethane production from anaerobic digestion of green and food waste. Bioprocess and biosystems engineering, 39(6), 977-992. https://doi.org/10.1007/s00449-016-1577-x

Research interests

In a broad perspective my current research seeks to support the development of low-carbon energy, industrial and agricultural systems, especially those related to the developing bio- and circular economies in areas such as bioenergy, bioprocessing, bio-based production systems and environmental biotechnology.

I apply process modelling and simulation to develop integrated models that can be used to design, analyse and optimise systems that involve combinations of processes and technologies, and assess them against sustainability criteria using techniques such as technoeconomic assessment (TEA) and lifecycle assessment (LCA).

A key focus of my work seeks to address the role that anaerobic digestion (AD) and biogas can play in future energy, agricultural and bioprocessing systems such as biorefineries, algal biofuels, intensive horticulture and thermochemical energy systems. I am also interested in novel modes of operation such as biomethanation and dispatchable/flexible biogas production, and emerging biomass resources and residues that may be particular suited to valorisation through anaerobic digestion.

Alongside the role of AD in developed economies as a means to valorise biomass residues as part of an integrated bioresource management system (i.e. circular economy), my research also covers the role that AD can play in developing countries as a means to improve quality of life and promote sustainable development. The benefits of AD in alignment with the Sustainability Development Goals are well documented and include improved sanitation and public health, access to clean energy, improved economic opportunities and gender equality.

Some examples of the research methods I use include:

1. Biochemical and physicochemical modelling for biogas, bioenergy and other bio-systems, and including other technologies and processes (e.g. energy, wastewater treatment, horticulture)

2. Systems integration/process modelling leading to design, optimisation and development of control and operational strategies

3. Assessment of sustainability metrics through life cycle methods (LCA, LCC)

4. Laboratory-scale bioreactor studies for proof of concept (e.g. TRL 2-4), to inform scale-up and for validation/supply of primary data to modelling studies

5. Assessment and refinement of industrial-scale systems using laboratory analysis and modelling

If you are interested in working with me, or studying for a PhD in any of these areas please contact me.