Project highlights

  • Examining emissions from smouldering combustion to improve application sustainability; 
  • An industrial placement with the world-leading smouldering company in Canada; 
  • Training in state-of-the-art techniques in smouldering diagnostics and microbiology 

Overview

Over one billion people cannot access safe drinking water. Even a robust treatment network – like used in the UK – cannot adequately protect water resources, as a recent 2022 UK parliament report revealed that not a single river in England met good chemical status (Environmental Audit Committee, 2022). This environmental contamination can be improved through more effective treatment of waste sources – particularly those with hazardous compounds, such as emerging contaminants.  

Applied smouldering has recently emerged as a scalable, energy-efficient, and economical thermal technology to treat hazardous wastes (Torero et al., 2020). Indeed, nearly 15 years of successful research and commercial activities from team members have demonstrated that smouldering systems are uniquely well-suited to manage a wide range of challenging wastes with hazardous compounds (Gerhard et al., 2020). These systems exhibit strong sustainability metrics due to their energy efficiencies and low-infrastructure requirements. However, the gaseous emissions produced from smouldering systems persists as a major knowledge gap, due to the complex mixture of gas production dynamics across smouldering conditions. These gases include beneficial compounds – such as H2 (Brown et al., 2024) – along with negative ones – such as CO2, CO, and unburned hydrocarbons (Rashwan et al., 2023) 

Breakthrough multidisciplinary research is needed to improve understanding of smouldering emissions, and sustainable pathways for emissions treatment.   

This project will leverage emerging smouldering and microbiology research at the Open University to (i) better understand emissions dynamics and (ii) understand its bactericidal properties. Future microbe-based systems may provide a sustainable pathway towards treating and potentially valorising the emissions – for example, in transforming carbon sources such as CO and CO2 into useful chemicals – such as ectoines (Cantera et al., 2022). Therefore, ongoing research excellence will be leveraged in this project to advance a novel and sustainable waste treatment strategy that addresses the critical environmental challenge of pollution (Figure 1).  

This project will focus on tracking the key gaseous emissions outputs across smouldering conditions relevant for waste applications. Moreover, select gaseous mixtures will be sampled and exposed to microbes that exhibit potential to treat or valorise fractions of the smouldering emissions to assess the emissions’ bactericidal properties. 

A process flow diagram showing the emissions from smouldering and how it may possibly support or hinder microbes.

Figure 1: A process flow diagram detailing the key smouldering, emissions analysis, and microbe experimental approaches embedded in this research project. 

CENTA Flagship

This is a CENTA Flagship Project

Case funding

This project is suitable for CASE funding

Host

The Open University

Theme

  • Climate and Environmental Sustainability
  • Organisms and Ecosystems

Supervisors

Project investigator

Co-investigators

How to apply

Methodology

A combination of smouldering and microbiological techniques will be used to further the understanding around smouldering emissions and its bactericidal properties. Smouldering experiments will be performed to track emissions across conditions, e.g., with different wastes, injected air flow rates, and O2 concentrations. Candidate wastes may be from municipal, industrial, and agricultural sources. Moreover, select emissions subsamples will be taken for microbiological investigations. The microbiology experiments will identify if select microbes can survive when subjected to smouldering emissions. Established analytical chemical techniques will be used to track smouldering emissions, including continuous FTIR and IR-based measurements, and discrete samples for GC-MS analyses. The student will have access to additional techniques at the partner organisations that can be used to identify microbial interactions.  

Training and skills

DRs will be awarded CENTA Training Credits (CTCs) for participation in CENTA-provided and ‘free choice’ external training. One CTC can be earned per 3 hours training, and DRs must accrue 100 CTCs across the three and a half years of their PhD.  

The student will be trained in specific laboratory-based techniques in applied smouldering, emissions measurements and data analysis, molecular biology (e.g., DNA extraction, PCR, library preparation, and DNA sequencing), and culture-based microbiology by members of the research team. A placement with Savron will enable participation in research, development, and deployment of commercial smouldering systems worldwide. The student will benefit from additional skills development opportunities offered by the Open University, e.g., communication skills, time management, and academic writing. 

Partners and collaboration

Gavin Grant (Savron) is an environmental technology expert, specialising in hazardous materials treatment. Savron employs smouldering technologies to eliminate environmental liabilities.  The research project and placement will expose the student to cutting edge environmental technology development.  

Tim Goodall researches molecular tools to understand the composition and function of communities – combining functional and molecular analyses to improve our understanding of biogeochemical cycles, sustainability, and anthropogenic impacts. Tim is a technical lead for DNA sequencing within the Molecular Ecology laboratories, and provides training and support to students and researchers in molecular techniques and data processing. 

Further details

For any enquiries related to this project please contact Tarek Rashwan, [email protected]. 

For additional details please the following profile pages: 

To apply to this project: 

  • You must include a CV with the names of at least two referees (preferably three) who can comment on your academic abilities.  

Applications must be submitted by 23:59 GMT on Wednesday 8th January 2025.  

Possible timeline

Year 1

Perform a literature review of smouldering emissions and relevant microbiology literature. Complete training in smouldering and microbiological methods. Conduct preliminary experiments using various waste sources and smouldering conditions to map out the emissions profiles. Complete upgrade report and mini-viva.

Year 2

Undertake placement with the CASE partner, Savron. Complete the smouldering experiments mapping out emissions characteristics and select key emissions conditions to subsample for follow-up microbiological experimentation. Present in-progress results at a waste conference (e.g., IWWG Sardinia conference).

Year 3

Refine all experimental activities towards preparing and submitting a manuscript. Present data at an international conference (e.g., ISWA international conference). Write and submit thesis. 

This project will leverage key research tools established at the Open University, including: (i) purpose-built smouldering equipment – including various continuous emissions analysers and an on-site specialised GC-MS facility, (ii) additional analytical chemistry equipment, (iii) existing metagenomic datasets from relevant microbes, and (iv) a decade’s worth of experimental smouldering data and in-house numerical modelling capabilities. This access to key research infrastructure ensures project resiliency and minimises potential delays. Moreover, the supervisory team has multiple strategies to progress the student with extensive digital infrastructure readily available at the Open University. 

Further reading

BROWN, J. K., RASHWAN, T. L. & GERHARD, J. I. 2024. Hydrogen-rich syngas derived from smouldering biomass and hydrocarbon wastes. International Journal of Hydrogen Energy, 72, 839-849. 

CANTERA, S., TAMARIT, D., STRONG, P. J., SÁNCHEZ-ANDREA, I., ETTEMA, T. J. G. & SOUSA, D. Z. 2022. Prospective CO2 and CO bioconversion into ectoines using novel microbial platforms. Reviews in Environmental Science and Bio/Technology, 21, 571-581. 

ENVIRONMENTAL AUDIT COMMITTEE 2022. Water quality in rivers: Fourth Report of Session 2021–22. London, UK: The House of Commons, UK. 

GERHARD, J. I., GRANT, G. P. & TORERO, J. L. 2020. Chapter 9 – Star: a uniquely sustainable in situ and ex situ remediation process. In: HOU, D. (ed.) Sustainable Remediation of Contaminated Soil and Groundwater. Butterworth-Heinemann. 

RASHWAN, T. L., FOURNIE, T., GREEN, M., DUCHESNE, A. L., BROWN, J. K., GRANT, G. P., TORERO, J. L. & GERHARD, J. I. 2023. Applied smouldering for co-waste management: Benefits and trade-offs. Fuel Processing Technology, 240, 107542. 

TORERO, J. L., GERHARD, J. I., MARTINS, M. F., ZANONI, M. A. B., RASHWAN, T. L. & BROWN, J. K. 2020. Processes defining smouldering combustion: Integrated review and synthesis. Progress in Energy and Combustion Science, 81, 100869.