Grundon’s Colnbrook incinerator could be replaced with green technology says Slough Borough Council
Notable for its inclusion in Slough’s revised submission to the Davies Commission is some carefully chosen language that suggests the “reprovision” of the Colnbrook incinerator could be an opportunity to replace it with green technology.
Long derided for its use of the misnomer Energy from Waste which masks the sheer amount of energy actually expended in the combustion process, Slough has mooted the possibility of switching the incinerator, the largest in the country, to anaerobic digestion technology should it be rebuilt under Third Runway plans.
The almost throwaway comment in the submission will be seized upon by environmentalists and air quality campaigners, although it’s not all good news:
Reprovision of a more modern Energy from Waste plant making the best use of new technology (including anaerobic digestion). New chimney technology could also be employed reducing chimney height and relaxing the requirement on location of the plant.
While this is, of course, no more than a feint possibility of a glimmer of a silver lining in the scheme of things, it is probably more a reflection of the difficulties Slough Borough Council will face as it tries to push a new incinerator through the planning process.
Viridor, partner to Grundon in Colnbrook, is also building the South London Incinerator in Sutton which finally got approval following a Judicial Review decision in November. The heights of its two chimneys had to be increased from 85 metres to 95 metres (311 ft) to ensure better dispersal in the existing air quality management area there. The chimney of the Colnbrook incinerator has a height of just 75 metres while the new DHL incinerator already approved is to be just 32.37 metres.
And its location in an area already adjacent to 4 Air Quality Management Areas (two established in 2005 just after the enlarged incinerator was approved) will add to the problems.
Incineration of waste has been strongly criticised by campaigners because it undermines recycling, adds to climate change; and causes pollution from air emissions and toxic ash. In recent years some local authorities have started considering other options for dealing with residual waste, including pyrolysis, gasification and plasma arc technologies which are better but still rely on combustion. It is often unclear exactly what emissions will be involved, and what sort of ash or other residue will be produced.
Anaerobic digestion is a biological process similar to composting, but without air. Micro-organisms break down organic matter into simpler smaller compounds and reduce its bulk or “mass”. Unlike composting, which overall always consumes energy, anaerobic digestion can be used to create energy. The biogas produced can be used to generate electricity, while in some installations there is zero waste.