An innovative in-vessel tunnel composting system

The batch tunnel composting demonstrator project under construction at St Ives, Cambridgeshire, UK, is one of a number of similar projects funded by the UK Department for Environment, Food and Rural Affairs as part of the New Technologies Demonstrator Programme (NTDP). The St Ives project includes the design, build and assessment of a new in-vessel composting plant and its demonstration to local authorities to highlight the central role of composting in efforts to divert biodegradable municipal waste (BMW) from landfill. Current statistics show that several million tonnes of BMW are landfilled each year in the UK, much of which could instead be composted. Assuming all current composting facilities are working at full capacity, over 100 new plants capable of processing 100 000 t per annum would be required to compost this volume of waste. The NTDP aims to present the technical, environmental and economic viability of new techniques to divert BMW from landfill and encourage the construction of further processing facilities. The new St Ives composting plant will be equipped with an innovative system to heat the walls and floors of the tunnel in order to ensure the entire composting mass reaches the temperatures specified by the 2005 Animal By-Product Regulations (ABPR) and reduce the risk of cold spots. The project will assess the effectiveness of this heating system.