A year after a £6 million investment by Public Power Solutions to turn what we throw away into fuel was launched, the project is proving successful in diverting waste from being dumped in the ground.
And instead of having to pay £4 million annually in landfill charges, Swindon Borough Council is receiving benefits from a reduced cost of disposal as well as income from improved recovery of recyclables.
The waste to fuel plant at Waterside Park was designed and managed by Swindon Council company Public Power Solutions Ltd and puts the town at the forefront of waste management in Britain.
Residents currently separate about 35.8 per cent of waste – glass, paper, plastic and garden waste – for kerbside collection, recycling and resale back into industry – down from 50 per cent in 2010. People also take bulky items to the household recycling centre at Waterside Park, adjacent to the Solid Recovered Fuel Plant where every day up to 200 tons of black bin rubbish picked up from the kerbside is taken.
There it is mechanically sorted on long conveyor belts which carries waste through a series of rotating drums, sieves, vibrating screens, air blowers, magnets and magnetic force fields to separate material that can be recycled, such as grits and metal, from that which can be further processed.
At the end of the conveyor belt the separated and shredded waste is passed through a giant dryer to reduce the moisture content to flakes of solid recovered fuel (SRF), waste that has been dried to a specified level to produce a higher quality fuel. This is then baled and transported to a power station in Latvia or packed into containers and taken to Portugal to power cement making kilns.
Christabel Banks-Coffey, Head of Waste Solutions – pictured top – said: “Swindon is the only local authority in the country which has set up an SRF plant and the long term investment is paying off. We launched in late 2013 and are now diverting 90 per cent of the waste that used to go into landfill. Every ton of waste being dumped in the ground costs the council taxpayer in the region of £103.
“Over the last year we’ve processed 57,000 tons of waste but from 1st February, with the introduction of new shift patterns, we aim to deal with 70,000 tons. The plant has the capacity to deal with 90,000 tons a year so we’re developing a market in local waste by taking material from private waste contractors. The plant was built to cope with the continued expansion of the town.
“Our plant started by producing Refused Derived Fuel (RDF) which is not such good quality because of the higher moisture level. The upgrade to SRF means we produce fuel with a high calorific value to deliver a consistent energy output needed for different industrial processes. None of the fuel is used in Swindon, it’s all used elsewhere. Unfortunately there isn’t yet a market in this country, but there is demand for SRF in Northern Europe and Portugal.”
Some waste is still difficult to deal with. Mattresses, being large to handle and full of densely woven material and steel springs which are difficult to disassemble, still have to go to landfill. uPVC windows and doors contain harmful chemicals if burnt, and are also buried. Shoes and trainers are problematic too as they have a high calorific value and PPS is testing equipment to break down and shred them.
Christabel added: “In the last six months PPS has also introduced an improved metals recovery sorting system. It’s surprising how much metal we pick up from black bins, about 2 tons a day. Aluminium cans, which could be put into recycling boxes, make up the bulk of the metal. There are a lot of pots, pans, woks and also old washing racks, and also high value metals like lead, copper and brass.
“This is separated from general waste and taken into another building where a team of people physically pick through the metal on a conveyor belt before it goes past a magnet. The metal is then mechanically sorted again and baled ready to be picked by metal recycling merchants. This cleaned ferrous and non-ferrous metals is worth a lot more than if left mixed with plastic bags and dirt.
“This year we will be carrying out tests on how to clean the sand, grit, vacuum cleaner dirt and cat litter mixed up in the black bin waste. This is sieved out from the waste sorting line and dumped into landfill because its contaminated. If it can be efficiently cleaned we can recycle it.
“As a company we’re always looking at new technologies which we can use to turn waste into a value product, and also find local markets for it.”
PPS might be using a combination of technology and physical effort to sort waste and Christabel says the council taxpayer would be helped if all residents see their service as the last in the waste chain which is:
• don’t produce so much waste
• reuse it where possible
• sort it into recycling boxes for collection or take large items to Waterside Park
• put it into the wheelie bin for responsible disposal.
Find out more at: www.publicpowersolutions.co.uk
All images by Richard Wintle of Calyx