Building with a fresh perspective

July 6, 2011

Construction work on our first AD plant in March, Cambs, is moving ahead. The digestion tank is nearing completion, awaiting its first 4000 cubic metres of food and non-food digestibles. The next bits of the building jigsaw are designed to purify the water and freshen the air…

The grandly named Process Aeration Filtration tank actually has a simple but vital role: to help clean the water that will be removed from digestate as it is processed in the digestion tank.  And its mission doesn’t stop there – the clean water is then recycled back into the digestion process.

This nondescript metal box is the bio-filter, another vital component for the AD plant. 80 tonnes of wood bark lining the filter will bond with a ‘bio-film’ to act as a giant ‘odour-eater’ while the air in the waste reception hall is changed up to 18 times an hour.  In line with the sustainable values practised at Local Generation, after seven years the bark will be recycled back into the AD process rather than going into landfill.

Any odour remaining after air has passed through the biofilter doesn’t stand a chance once it reaches the elegant but highly efficient odour stack. Extensive air modelling checks by the Environment Agency dictated the height of the stack.

That’s all for this post.  Next time, we’ll be reporting on the headlines and highlights of the second UK AD & Biogas Conference, which Local Generation is attending on the 6th and 7th of July at the NEC in Birmingham.  We’ll be hearing from senior figures in government and industry about the latest developments in this exciting new source of green energy – and reporting back!