No WASTER: Novel integrated WASTE Refining technologies for a circular economy

Municipal Solid Waste (MSW) often ends up burned or disposed in landfills and dumping sites, especially in developing countries. These disposal methods release greenhouse gases and toxic substances, contaminating air and groundwater and threatening the health of human population. Most of the materials in the waste are recoverable or can be turned into useful energy and products and recycled for local consumption, thus enabling a circular economy. The main challenges of the waste sector include how to deal with a heterogeneous raw material and how to recover valuable products that are rather diluted or in a highly complex matrix due to poor separation and sorting at source. Furthermore, waste processing following the traditional waste management hierarchy may overlook potential synergies between different waste processing technologies.

The aim of this challenging project is to develop solutions to go from waste to energy and a variety of recovered products through the integration of proven and novel waste processing technologies. This could be through an integrated waste refinery or a network of processing centres in a particular locality. The work will involve analysing waste generation in an urban area (initially Mexico City, one of the world’s biggest cities producing a staggering 13k tonnes of MSW per day; but can also be an area of your interest). This will allow knowing what is in the waste, how much and what can be recovered and guide the design and planning of waste processing facilities. Up to half of total MSW is organic waste coming from food waste, paper, and garden waste. This project will specially explore a novel integrated concept for a waste biorefinery based on the anaerobic digestion (AD) platform, combined with other biochemical and thermochemical processes (e.g. pyrolysis, hydrothermal liquefaction). The project may involve carrying out pilot scale trials and feedstock characterisation, urban metabolism modelling, process integration and optimisation methods to recover useful products (e.g. organic acids, char and bio-oil), nutrients (e.g. phosphorous) and clean water. Techno-economic and life cycle assessment will be used to develop indicators of sustainability.

The waste management hierarchy will be updated to account for interactions among waste processing technologies that could make them more efficient and also profitable. Scope for new business opportunities and support for existing waste companies could be drawn from the results of this project. An analytical tool to assess various processing routes will also be created to facilitate communication and engagement with stakeholders. The project is expected to make an impact in advancing towards a circular economy while solving waste related environmental issues in urban areas in developed countries and especially in developing countries where urbanisation is taking place rapidly.