Written by Fergus Dignan
5 GT members, plus another member of the public, visited the Gloucestershire Energy from WasteFacility on the evening of the 27th October 2022. The event lasted from 7.00pm to 9.50pm.
We were hosted by Diane Green, an education facilitator. We listened to a presentation in the Education Centre and were then shown around the site. The mechanism of the energy generation is known as ‘Energy from Waste’, and instead of burying non-recyclable household waste in landfill, non-recyclable household waste which is collected from all over Gloucestershire is combusted instead with over 90% of waste received diverted from landfill. The site became operational in 2019.
The Facility was built on a former RAF airfield. Indeed, the section of the M5 right next to the Facility is the former main runway! The name ‘Javelin’ comes from one of the aircraft that used to fly there.
She explained that the lorries arriving on site are weighed and they then deposit their non-recyclable waste loads in the waste bunker in the Waste Reception Hall. The lorries are then reweighed upon leaving. Less than 100 lorries use the site each day either delivering waste or process reagents or collecting materials generated by the treatment process.
There are six main elements to the Javelin site: the Waste Reception Hall, Waste Bunker, Boiler Hall, Turbine Hall, Flue gas treatment area and incinerator bottom ash processing plant.
The waste is burnt at between 850 - 1,000 degrees C and on average produces and exports at least 14.5 MW, or around 116,000 MWh per year, of electricity to the National Grid providing the equivalent electrical energy to power 25,000 homes.
The flue gas treatment plant is used to ensure that emissions from the Facility never exceed limits which are imposed by the Environment Agency as part of the facility's Environmental Permit. Lime and activated carbon reagents are stored onsite in separate silos and are injected into the process to neutralise acidic gases and capture particulate matter via a series of bag filters. However, there is no mechanism in place for trapping the CO2 that is generated in the incinerator. Diane explained that, under current regulations, there is no requirement.
Another issue is that there are bound to be some recyclable items that are mixed in with the household waste. Diane said that there are spot checks done on lorries entering the site each week, but this is done for detecting more ‘heavy duty’ items such as gas canisters.
Per year, about 190,000 tonnes of waste are burnt and there are 40,000 tonnes left over. This is a mixture of metals which are removed and sold for recycling, and aggregates, which is the ash deposit at the bottom of the furnace and is formed from noncombustible materials such as glass, ceramics and stones. The aggregates can be used in the construction industry, for roads and buildings.
More detailed information can be found at https://www.ubbgloucestershire.co.uk/