Organic waste from pigs on a farm in Leicestershire, UK, is helping to power an estimated 700 homes and reduce landfill waste by 18,000 metric tons each year. The pig waste, combined with other food waste, is being used to produce biogas capable of generating the equivalent of around 1.2 megawatts of electricity. The electricity is being exported onto the local energy grid used to power homes, as well as the pig farming facility.
The technology used to convert waste into energy was designed and built by a UK company, PROjEN BioEnergy, who were honored earlier this month by the Institution of Chemical Engineers (IChemE) at its annual award ceremony to celebrate innovation and excellence in chemical engineering across the world.
Using a process called anaerobic digestion - where natural bacteria are used to treat biodegradable materials - PROjEN's work has resulted in other major benefits. The farm's carbon emissions have been reduced by offsetting electricity and heating consumption. Waste and by-products normally destined for landfill and incineration has been avoided.
In addition, the process produces a high quality pasteurised fertiliser, which is weed free and rich in nitrogen. Around 96 million tonnes1 of farm manures are applied to agricultural land each year in the UK, with strict controls. Pasteurisation helps to minimise the risks of food-borne diseases such as listeria and salmonella.
IChemE's chief executive, David Brown, said: "The work of organisations like PROjEN shows the potential of chemical engineering to transform discarded waste into valuable commodities to benefit industries like farming.
"The benefits from just one farm are impressive. With an estimated four million pigs2 in the UK alone, producing millions of tonnes of by-products each year, the potential for energy production, from a sustainable source, is significant".
The role of chemical engineers in the energy sector is explored in IChemE's latest technical strategy, Chemical Engineering Matters. The strategy also includes actions chemical engineers are taking on other global challenges including health, water and food.