BV to pioneer liquid AD technology

BV Dairy is aiming to cut its carbon footprint by more than 65 per cent by pioneering the use of liquid anaerobic-digestion (AD) technology.

The move is expected to allow the dairy to reduce its CO2 emissions by approximately 1,200 tonnes per year and save an estimated £150,000 per year by generating more than 75 per cent of the site’s electricity consumption once the system becomes fully operational in August 2010.

A liquid digester designed and built by Clearfleau will produce biogas from the treatment of liquid waste that will then be used to feed a combined heat and power (CHP) technology designed, supplied and operated by Ener-G to convert the biogas produced into energy.

The 190kWe CHP system will be capable of generating 1,539MWh of electricity and 1,685MWh of heat per annum from effluent, dramatically reducing the dairy’s reliance on fossil fuels.

The majority of electricity will power existing dairy operations, with the remainder sold into the National Grid. Surplus heat will be used in the production process. In addition, small amounts of de-watered digestate will be produced, which will be used as a soil conditioner and fertiliser.

Established in 1958, BV Dairy currently processes around 35 million litres of milk per year, sourced from 35 farms located near its site. The product range includes fresh and cultured dairy products for sale to the UK’s food manufacturers and food service operators.

Funding for the project has been provided under the WRAP (Waste and Resources Action Programme) Environment Transformation Fund, supported by the Department of Energy and Climate Change. This follows an earlier small-scale pilot project to test the AD operation at the site, which was carried out by Clearfleau. The mobile plant has just completed further dairy trials and will be used on other projects in the brewing and food-processing sector during 2010.

Jim Highnam, managing director of BV Dairy, said: ’This is a fantastic opportunity, not just for BV Dairy, but for the whole UK dairy industry, to be at the leading edge of renewable energy technology. We need to release the energy value of these unavoidable liquid wastes.’

According to estimates by Dairy UK, if the AD system was replicated across the UK’s dairy sector some 346,000 tonnes of CO2 could be saved annually.

The CHP system is being hired from Ener-G for a two-year period, prior to capital purchase.