How Does the Facility Work?

How Does the Facility Work?

Waste trucks are weighed when arriving at the facility. Household and business waste is unloaded into a storage bunker and thoroughly mixed using overhead cranes. The tipping hall and waste bunker are maintained under negative air pressure by drawing the air into the combustion process so that the odours associated with waste are captured and destroyed by the heat.

The waste is loaded by the cranes into hoppers which feed three combustion chambers, which operate in a self-sustaining process at a temperature greater than 850 degrees Celsius. As waste is burned, the heat converts water in the steel tube-lined walls into high pressure steam. The steam turns a turbine-driven generator to produce electricity for the National Grid which is then consumed by homes and businesses.

Steam from the process is later cooled, condensed back into water and returned to the boiler tubes, making it an efficient 'closed loop' system.

Combustion reduces the volume of waste by 90%, leaving an inert ash and metals for recycling. Bottom ash from the grate is sent off site where metals are recovered for recycling and the remaining material is processed into secondary aggregate for reuse in the construction industry. Fly ash collected in the air pollution control equipment and resulting residues (together known as APCr) are stored in silos for removal from the site in sealed tanker vehicles.

Modern air pollution control equipment ensures that emissions are fully comply with stringent standards set out in the facility's Environmental Permit. Acid gases are neutralised using lime in a semi-dry scrubber reactor and activated carbon is injected to capture and control heavy metals and dioxins. The baghouse filters capture emissions of particulates and other residues from the flue gas treatment system.  

Throughout the process, emissions are monitored closely in the facility’s control room via a real-time continuous emission monitoring system.