Rainham Waste Processing Facility, UK

With the requirements of the Landfill Directive now in place in UK legislation and policy, the need for new waste management technologies to deal with the biodegradable component of waste is current and pressing. The need to further increase recycling also remains firmly on the agenda. Scott Wilson was appointed by Cleanaway to undertake the EIA for its proposed autoclave processing facility (APF).

The APF would be located on an existing industrial/waste management estate adjacent to Cleanaway’s landfill site in Rainham, Essex. The site lies close to the northern bank of the River Thames, and the APF would take advantage of this by receiving waste by river barge instead of by road.

The waste would be steamed at high temperature and pressure for approximately one hour in a steel vessel (autoclave). The process has a number of effects on some of the materials. The most significant changes occur to the biodegradable components (e.g. paper, card, food): most are transformed into a fairly uniform material known as ‘floc’.

An important effect is that the process biologically sterilises the waste. The floc would be used on the nearby landfill as either alternative daily cover material or as restoration material. Most other components of the waste, including plastics and metals, tend to retain their original shape, and these would be separated mechanically and sent off-site for recycling.

Between about 1920 and 1970, the site formed part of a tip accepting refuse, slag, chemicals and other industrial waste, and as such the land is contaminated. The most pertinent issues covered by the EIA were therefore land contamination and its relationship with water quality. Further survey work, risk assessments and design/construction recommendations were presented in order to minimise impacts and control risks.

The EIA also involved an assessment of the need for the development, alternatives to it, and whether the proposals represent the best practicable environmental option (BPEO).