Biogas Infeed

Giant hopper helps West Country biogas project

A high capacity biogas infeed hopper manufactured by Tong Engineering is now helping in the generation of electricity for an ambitious Somerset biogas project.

Cannington Cold Stores is developing a plant that will be capable of generating more than 2000 kW / hour from digesting a mixture of silage, waste from yoghurt and orange juice manufacture, and livestock slurry. Each of the three 650 / 700 kW plants being built needs at least 20 tonnes of silage per day to be fed slowly into the digester and the challenge for Tong Engineering was to supply a biogas infeed hopper capable of holding enough silage to keep the process going for one to two days.

The 50 cubic metre hopper holds 35 – 40 tonnes of maize and grass silage which is fed slowly and evenly into the Quickmix using a specially designed teaser unit.

Mike Roe, owner of Cannington Cold Stores, says they looked at five different types of biogas infeed hoppers before choosing the design from Tong Engineering — the Spilsby company he had been dealing with for 30 years.

The decision to invest in the biogas plant stemmed from an annual £300,000 bill for powering the 45,000 cu m facilities of frozen and chilled storage for vegetables, cheese, meat, fruit and other foodstuffs. Already the electricity from the first plant is powering the cold storage complex and supplying around 300 kW to the National Grid.

This plant began generating electricity from the methane gas in July, with the second scheduled to be in production in April. Silage from 800 acres of maize and grass will be used in the process, with the mixture fermenting in giant tanks for 30 days and then after drying being returned to the land as a valuable fertiliser.