The CircBioCityWaste project is based on the key principle of ‘circular bioeconomy’ focusing on the sustainable, resource-efficient valorisation of three urban waste streams (anaerobically digested (AD) sludge from municipal and dairy processing and organic portion from black wastebin). It aims to develop a first-of-a-kind integrated biorefinery concept in Ireland via ‘cascading’, using ‘end-of-waste’ approach, CircBioCityWaste demonstrates a novel concept of new value chains from urban waste biomass sourcing to biobased agrochemicals (biostimulants and biofertiliser) for sustainable agriculture focusing on plant growth and soil health, and bioenergy as a sustainable source of clean energy.

This biorefinery concept will start with the collection of ‘AD sludge’ from selected waste streams followed by developing pretreatment and extraction technologies/processes for recovering fine agrochemical (biostimulants). The residual waste will be combusted at low temperature using fluidised bed combustion to produce bioenergy. This process significantly reduces waste volume, destroys persistent organic pollutants and lead to mineralisation and concentration of phosphorus and other nutrients in the resultant ash, that will be explored as biofertilser. The impact of agrochemicals on growth of economically important crops will be assessed in pot trials.

CircBioCityWaste will evaluate the sustainability of multiproduct biorefinery and assesses the economic, social and environmental impacts of the developed products/materials or processes using life-cycle assessment methodologies. To effectively generate a comprehensive perspective on the opportunity of exploiting urban waste as a valuable resource, the CircBioCityWaste project has assembled a very strong interdisciplinary team from three Irish universities and expert/representatives/advisors from industry and local authorities, balanced across discipline, expertise and gender.

Leveraging partners’ knowledge, resources and relationships, CircBioCityWaste will build on prior state-of-the art research, and aims at delivering a number of outcomes including:

1. Develop technologies to produce three agrochemicals from urban biowaste, opening up new possibilities for their production and marketing on large scale in Ireland.
2. Generation of clean bioenergy replacing fossil fuels.
3. The de-carbonisation of urban biowaste management with, amongst others, a strong component of long-term carbon sequestration.