Burdens launches small-scale anaerobic digestion system for food waste

AD Plant in South Wales

Burdens has unveiled the UK’s first small-scale commercial anaerobic digestion (AD) system for food waste. The digester is also the first of its size to be Animal By Products Regulations (ABPR) compliant, meaning that it can handle general food waste, including meat.

The system has been designed to speed up the adoption of localised AD food waste treatment plants by making them commercially viable. Capable of handling between 3,000-5,000 tonnes of food waste per year, the new small-scale plants are targeted at private waste collection companies, local authorities, food manufacturers and retailers, and community interest groups.

“It is becoming clear that AD has substantial potential in the UK and that developing the technology at a smaller scale is a key part of this”, said Paul Thompson, Head of Policy at the Renewable Energy Association.

“The benefits of local processing of food residues extend beyond renewable energy supply and include local jobs, community engagement and less transport of waste over long distances.”

Currently only three (out of a total 32) dedicated AD food waste treatment plants in the UK specialise in municipal-sourced food waste. Burdens’ pilot plant in Llangadog, Carmarthenshire (pictured), is one of these three plants and is the only one to provide dedicated local, rather than centralised, service. It has been testing the system for the past two years.

Companies or groups who wish to take advantage of the compact system are able to do so by either buying the system outright, or by partnering with Burdens through a fully funded option in which Burden will take on the costs of running and maintaining the system, and will be reimbursed through the Feed in Tariff and Renewable Heat Incentive.

“We have set out to make small-scale food waste treatment financially possible”, said Will Kirkman, Head of Environmental Projects at Burdens.

According to Kirkman, misconceptions about the viability and benefits of small-scale AD plants have previously held back this sector of the market, slowing the growth of food waste recycling in the UK.

“Now for the first time in the UK we can actually show commercially viable plants in action, clearly demonstrating the benefit of locally-based solutions”, he said. “This should go a long way to removing misplaced concerns about smaller scale AD food digesters, help increase uptake and consequently improve recycling rates of municipal and commercial food waste.”

Most food waste in the UK is composted, incinerated or goes to landfill the company says, rather than being recycled through anaerobic digestion – a process that creates power, heat and biofertiliser.

Burdens’ patented system passes food waste through a macerator and chopper pump, feeds it into holding tanks, and – after three days – empties and divides it between high fibre content and liquid remains. The liquid is reused to wet new food waste, and high fibre material is combined with waste wood to produce a high quality low ash pellet to be used in wood burners. Biogas produced by the plant is stored and recycled for use within the site generator.

More details of the small scale commercial anaerobic digester can be found on the Burdens website.