Anaerobic Digestion "Big Opportunity" for Municipal Waste

Urban-based local authorities should consider anaerobic digestion (AD) as an alternative to in-vessel composting for the recycling of municipal biodegradable food waste, according to researchers at WRAP.

Speaking today (23 April 2007) at the annual Recycling and Waste Forum in Birmingham on Thursday, WRAP's organics supply programme manager Louise Hollingworth said: "In-vessel composting is obviously very established in the UK but there are only a couple of AD plants in the UK taking biodegradable municipal waste.

Anaerobic digestion plants, like this one run by Greenfinch Ltd in Shropshire, could be the future for municipal waste in the UK according to WRAP:

There is a big opportunity for the UK to learn from Europe and optimize collection schemes and perhaps for urban authorities as AD solutions are something that could be used,

she said.

Ms Hollingworth was discussing a report commissioned by WRAP and published this March, entitled "Dealing with food waste in the UK".

The year-long study by Dominic Hogg of the consultancy Eunomia focused on the European picture for Anaerobic Digestion - a biological treatment conducted in the absence of air, which produces both a compost product and bio-gas that can generate renewable energy.

The study discussed the 124 operational AD plants throughout Europe and the "clear benefits" of the technology.

Ms Hollingworth also said that in the UK many local authorities are "concerned about the robustness of AD" and consider it an "unproven technology" however she said: "The European experience flies in the face of this."

Anaerbic digestion "has a stronger, overall environmental performance" than other technologies, she added.

AD could be seen to be an appropriate technology for urban local authorities as households in urban areas tend to collect a lower proportion of green waste.

Costs
WRAP's research also compared the cost of technologies processing biodegradable municipal waste and although AD technology came out as the most expensive, at £45-55 per tonne, in comparison to in-vessel composting at £35-45 per tonne, Ms. Hollingworth said that the possibility of selling the energy extracted from the process had not been included in the predicted costs. More at LetsRecycle here...