Fairfield In-vessel Composting site

Last year I went to Manchester to look round one of the few remaining wholesale fruit and veg markets still left in the UK.  New Smithfield Market is owned by Manchester City Council and plays an absolutely critical role in the provision of good value fruit and veg to other markets, cafes, schools, restaurants and catering outlets in the Manchester area.

Its one of those proper old-school places where if you get up at four in the morning you can go and buy fruit by the tonne at bargain prices, and after a bit of haggling, get yourself some pie and mash or a full english breakfast at the onsite greasy spoon cafe and catch up with the local traders whilst the rest of the city still sleeps.

The main reason I was interested in this site was really because of the composting operation it supports.  Because obviously where there is fruit and veg, there is lots of spoilage and waste. 

In fact they compost over 3,000 tonnes of organic matter each year.  Mainly this is food waste from the market but in order to balance this out they also throw in all the cardboard boxes and they take horticultural waste from local landscaping contractors.

The operation is run by Fairfield Composting, a non-profit making social enterprise set up for environmental objectives.  On a practical level its appears to operate much like some of the commercial scale composting operations that you will have seen before.  Incoming material is delivered to the site, where it gets screened, plastics removed, and the material is then shredded and then added into the composting vessel.

Because they are dealing with food waste the process needs to be in-vessel (to get up to the temperatures required to comply with Animal Byproduct Regulations).   The unique approach this site uses though is the Vertical Composting Unit (VCU).  This is partly down to limited space on the site. 

The VCU is contained inside a tall structure like a silo.  This holds an insulated, self-aerating chamber.  Waste is loaded into the top and the decaying matter trickles down with gravity.  For those of a technical mindset, there is a interesting description of the process on the manufacturers website here.

It takes only about 7 days to produce the initial compost (though it is then left out for open air maturation for several weeks more).   All compost produced is certified to PAS100 standard and sold to local allotments, schools and indeed back to many of the landscape gardeners who bring waste into the site.