Project highlights

  • Integrating biological and thermochemical methods to reduce pollution  
  • An placement with a world-leading national laboratory in Montréal Canada, with National Research Council Canada (NRC); 
  • Training in state-of-the-art techniques across the fields of microbiology, chemistry, and environmental technology 

Overview

Breakthrough multidisciplinary innovations are needed to achieve improved environmental sustainability and carbon neutrality within a safe, circular economy. Applied smouldering combustion has been shown as a novel environmental technology to economically treat challenging wastes with minimal energy footprints and limited infrastructure that otherwise pose environmental pollution risks – such as sewage sludge contaminated with per- and polyfluoroalkyl substances. However, the gas emissions from these systems are challenging to treat and often governs the operating costs and sustainability drawbacks. Smouldering emissions often contain CO2, CO, and H2O along with a complex mixture of unburned hydrocarbons (including acids, phenols, steroids, amides, sugars) and CH4 and H2 under certain smouldering conditions. However, smouldering emissions are notoriously poorly understood.  

In a separate discipline, astrobiology research seeking to define the limits of life has uncovered various extremophiles (i.e., organisms adapted to physical or chemical extremes) that are able to thrive in hostile environments. These extremophiles often possess unique adaptations not seen in other environments, including tolerance and metabolism of heavy metals and volatile compounds with antimicrobial properties. One unexplored pathway is using the waste smouldering emissions as a useful feedstock, to promote the selection of these extremophiles in this context, as opposed to a sustainability liability. These extremophiles could also be investigated for biomining of valuable compounds from the smoulder ash, enhancing the efficacy of the smouldering approach. 

This studentship will explore the combination of smouldering and extremophile waste treatment to ameliorate emissions from smouldering technologies. Together, this combination of technologies underpins a new circular economy approach to minimise environmental pollution and enhance the sustainability of waste treatment. The project will involve: (i) exploring how smouldering emissions vary with treatment regime, (ii) identifying extremophiles that metabolise smouldering emissions and smouldering ash, (iii) exploring how these microbial communities evolve with varying emissions and concentration profiles. 

A process flow diagram showing the combination of environmental technologies proposed in this research project. The diagram details how the emissions from waste smouldering can support microbial-based organic contaminant treatment and small organic molecule generation.

Figure 1: A process flow diagram detailing the key experimental approaches of 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 chemistry, microbiological, and smouldering techniques will be applied to investigate the pathways to treat sewage waste. Standard smouldering experiments will be performed to capture emissions needed for the microbiological investigations. The microbiology experiments will identify and isolate keystones species in the community (e.g., smouldering-gas utilisers, contaminant degraders, and small organic molecule producers). Detailed analytical chemical techniques – such as GC-MS, HPLC-MS, in-situ IR, and flow photospectroscopies – will be used to track the fate of organic contaminants. The student will have access to a range of 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 organic chemistry characterisation, molecular biology (e.g., DNA extraction, PCR, library preparation, and DNA sequencing), applied smouldering, analytical geochemistry, and culture-based microbiology by members of the research team. A placement with NRC will enable participation in microbiological research at a top international research institute in Canada. The student will also be trained in computer-based techniques, including bioinformatic analysis of sequencing data and smouldering data analysis. 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

Fabrice Tanguay-Rioux (National Research Council Canada, NRC) is an environmental technology research officer, specialising in pairing microbial treatments alongside thermochemical processes. The NRC has a world-class research environment that explores both fundamental and practical aspects of this novel pairing of processes and includes specialised facilities to allow scale-up studies up to commercial sizes. 

Megan Barnett is a microbiologist specialising in the role of microbes in weathering and rare earth element cycling and developing techniques for microbial detection and study. Their expertise will support this project enhancing our understanding of microbial life in extreme environments. 

Further details

For any enquiries related to this project please contact Michael Macey, [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 key processes. Complete training in microbiological methods, molecular techniques, bioinformatics, applied smouldering, and statistical analysis of large-scale datasets. Undertake preliminary field work collecting waste samples and performing initial chemical surveys of organic contamination. Test initial enrichments of extremophiles with smouldering waste gases.

Year 2

Undertake placement with the CASE partner. Conduct smouldering experiments to generate emissions needed and perform metagenomic analysis of the enriched samples to identify keystone species and chemical end-products. Present in-progress results at a national conference (e.g., Microbiology Society annual conference).

Year 3

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

This project will benefit from access to various key research infrastructure from The Open University, including: (i) existing metagenomic datasets from hypersaline environments and wastewater treatment experiments, (ii) a robust array of relevant analytical chemistry equipment, (iii) purpose-built smouldering equipment, and (iv) a decade’s worth of experimental smouldering data and in-house numerical modelling capabilities. This access to key experimental and digital research infrastructure bolsters project resiliency, as research work can be initiated rapidly. Moreover, in the instance of any potential restrictions to fieldwork or laboratory access, the supervisory team has multiple contingency strategies to progress the student’s progress via the extensive virtual tools available.  

Further reading

García, J. L., & Galán, B. 2022. Integrating greenhouse gas capture and C1 biotechnology: a key challenge for circular economy. Microbial Biotechnology, 15, 1, 228–239.   

Macey, M. C., Fox-Powell, M., Ramkissoon, N. K., Stephens, B. P., Barton, T., Schwenzer, S. P., Pearson, V. K., Cousins, C. R., & Olsson-Francis, K. (2020). The identification of sulfide oxidation as a potential metabolism driving primary production on late Noachian Mars. Scientific Reports, 10(1).  

Macey, M. C., Pratscher, J., Crombie, A. T., & Murrell, J. C. (2020). Impact of plants on the diversity and activity of methylotrophs in soil. Microbiome, 8(1). 

Macey, M.C., 2024. Genome-resolved metagenomics identifies novel active microbes in biogeochemical cycling within methanol-enriched soil. Environ Microbiol Rep 16. 

Rashwan, T. L., Fournie, T., Torero, J. L., Grant, G. P. & Gerhard, J. I. 2021. Scaling up self-sustained smouldering of sewage sludge for waste-to-energy. Waste Management, 135, 298-308. 

Robb, F. T., & Techtmann, S. M. 2018. Life on the fringe: Microbial adaptation to growth on carbon monoxide. F1000Research, 7 

Sorokin, D. Y., Merkel, A. Y., Messina, E., Tugui, C., Pabst, M., Golyshin, P. N., & Yakimov, M. M. 2022. Anaerobic carboxydotrophy in sulfur-respiring haloarchaea from hypersaline lakes. ISME Journal, 16, 6, 1534–1546. 

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.