PhD Studentship in: Food Waste to Sewer: Evidence, Infrastructure Resilience, Circular Economy and Policy Implications

Details

The University of Sheffield, Sheffield Water Centre in collaboration with InSinkErator UK and the EPSRC Centre for Doctoral Training in Water Infrastructure and Resilience

PhD Studentship in: Food Waste to Sewer: Evidence, Infrastructure Resilience, Circular Economy and Policy Implications

Stipend: This post will fully cover university tuition and provide a tax-free stipend for Home students of £26,546 per year.

Applications Close: 24th April 2026

Start Date: 28^th September 2026 (contract duration 4 years)

Food waste management sits at the intersection of climate policy, infrastructure resilience and everyday household behaviour. In the UK, the long-standing “3 Ps” principle (only pee, poo and paper should enter the sewer) shapes national practice, but limits innovation. At the same time, several countries now use food waste disposers to send food waste to the sewer, or hybrid systems that mechanically dewater the waste: the liquid fraction is sent to sewer for treatment and energy recovery, while the solid fraction is collected for composting or anaerobic digestion. These emerging approaches indicate major opportunities for carbon reduction, improved biogas generation and circular-economy integration, but their impacts on sewer performance and wastewater treatment remain poorly quantified.

Recent research at Sheffield demonstrated that disposer-derived food particles do not significantly increase blockage risk in UK sewer conditions, challenging a long-held industry assumption. The next step is to evaluate the wider system implications: hydraulic transport behaviour, biochemical loading, treatment-plant performance, sludge yield, aeration demand and whole-life environmental impacts. This PhD will deliver the first integrated, evidence-based assessment of disposer-inclusive, kerbside-only and hybrid food-waste pathways, providing the scientific foundation needed for sensible, infrastructure-aware policy development in the UK, EU and internationally.

Working closely with academic experts and InSinkErator UK (Whirlpool), the student will analyse food waste compositions from global regions, quantify how their biochemical properties change after grinding and mechanical separation, and model the resulting impacts across sewers, pumping stations, wastewater treatment works and anaerobic digesters. By combining biochemical experiments, hydraulic and process modelling, life-cycle assessment and policy evaluation, the project will determine where and when disposer-inclusive pathways can support more resilient, sustainable and circular water-infrastructure systems.

Throughout the project, the student will develop a broad and highly employable skillset, including:

• Practical biochemical analysis (COD, nutrients, solids, moisture, biodegradability).

• Operation of grinding equipment, filtration rigs and separator technologies.

• Sewer-hydraulics modelling and assessment of blockage, deposition and transport behaviour.

• Wastewater treatment modelling, including aeration energy, sludge production, nutrient removal and AD performance.

• MATLAB/Python-based data analysis, multi-source data integration and statistical modelling.

• Life-cycle assessment comparing environmental burdens and carbon impacts across multiple waste-management pathways.

• Policy analysis and the ability to translate technical evidence into clear recommendations for regulators and industry.

• Professional communication skills for engaging with water utilities, manufacturers, local authorities and national policymakers.

These competencies are strongly valued across the water sector, environmental consultancies, resource-recovery companies, local government, NGOs and regulatory bodies. Graduates with combined biochemical, hydraulic, modelling, data-science and policy skills are rare, and the project provides a powerful platform for careers in water engineering, sustainability, circular-economy strategy and environmental regulation. Interaction with InSinkErator UK and potential engagement with water utilities will also offer opportunities for industry placements, site visits and operational insight, further strengthening employability.

The project will generate new biochemical datasets on liquid and solid fractions of ground food waste, quantify their impacts on sewer and treatment systems, and explore how these effects vary with food-waste composition, separator cut-off size and local infrastructure characteristics. Advanced modelling will estimate consequences for sludge yield, aeration demand, nutrient loading and AD gas potential under various adoption scenarios. A comparative life-cycle assessment will evaluate kerbside, disposer-to-sewer and hybrid systems across multiple international contexts, identifying which configurations offer the greatest environmental and circular-economy benefits.

The results will form a robust evidence base for water utilities, policymakers, local authorities and technology suppliers, helping them develop low-carbon, resilient food-waste strategies aligned with circular-economy goals and infrastructure capability. For industry partners, the findings will directly support innovation in grinding and separation technologies and inform future engagement with UK/EU regulators.

This project offers a unique opportunity to work at the interface of engineering, biochemistry, sustainability, data science and policy - producing research with real-world impact and clear pathways into influential environmental, water and circular-economy careers.

The research programme to be completed in this project will be undertaken as part of the EPSRC Centre for Doctoral Training in Water Infrastructure and Resilience (CDT WIRe). WIRe is a collaboration between the three leading UK Universities in water resilient infrastructure. Students will benefit from a bespoke training scheme delivered by world leading experts from academia and industry including close and regular contact with industry and end user partners. WIRe is committed to promoting a diverse and inclusive community, and offer a range of family friendly, inclusive employment policies. For further information on the WIRe scheme visit: https://cdtwire.com/

The project will be supervised by Dr Andy Nichols, Dr Henriette Jensen and Professor Lenny Koh, in collaboration with partners from InSinkErator UK. There will be generous opportunities to travel to visit our academic and industry partners in both the UK and overseas.

Eligibility Criteria

This studentship is subject to standard RCUK eligibility criteria. It is open to all students with Home residency.

The selection criteria for the position are;

•      A good honours degree (or equivalent experience) in Engineering, Physical Science, Mathematics, Computer Science or a related subject.

•      Enthusiasm for research

•      Good level of written and oral communication skills, as appropriate for disseminating research and communicating with project partners.

•      Willingness and ability to collaborate with other researchers, industry and end-users.

•      Aptitude in a relevant area (e.g. data analysis, hydraulics, biochemical analysis, laboratory studies, wastewater systems, water engineering, circular economy, environmental policy) as evidenced by previous experience.

How to apply

Interested candidates should email a covering letter and Curriculum Vitae to Miss Lindsay Hopcroft (cdtwireapps@sheffield.ac.uk). For informal enquiries please contact: Dr Andy Nichols (a.nichols@sheffield.ac.uk)