The Science

The most active micro-organisms in the composting process are a wide variety of bacteria, fungi and actinomycetes. Composting provides a safe way to process and recycle green garden wastes such as grass, leaves, and tree trimmings. Household food waste and supermarket waste, such as fruit, vegetables, bakery, dairy, fish and meat products can also be safely composted.

Food and kitchen waste must be composted using a safe in-vessel composting system to comply with strict UK Government Animal By-Products Regulations (ABPR). Envar staff have over 30 years experience in the composting of organic waste materials to produce a compost that can be used as an agricultural fertiliser and soil improver. At the Envar site in Cambridgeshire, we utilise the Gicom b.v. batch tunnel composting technology.

In-Vessel Composting – from RESOURCE

This technology composts organic waste in a fully enclosed environment. The system is fully computer controlled. After filling the tunnels, the doors are closed and fans on top of each tunnel blow air through the perforated floors of the tunnels. The air passes through the composting materials and is then re-circulated within the tunnels. When the oxygen level within the tunnel drops below a minimum set level, fresh air is drawn in to the system. This allows a very tight control of oxygen levels and temperature within the composting material. The computer measures or calculates all parameters every 15 minutes. The system also includes an air scrubber and biofilter to minimise emissions to atmosphere.

The composting tunnels at the Envar composting site in St Ives, Cambridgeshire is also recognised as an exemplar composting facility. It was part of the UK Government’s New Technology Demonstrator Programme for waste treatment. The programme has undertaken 2 years of research and development to collate important data on optimising the composting process and determining its effect upon the local environment. Our staff have also advised over eighty local authorities, via study tours around the facility, to help Councils understand more about organic waste recycling. This helps Councils to decide the best option for recycling and the appropriate treatment technology to use.