The creamery in rural Cumbria produces cheddar cheese under the Lake District brand and is Europe’s first dairy processing site to feed bio-methane (up-graded biogas) generated entirely from cheese process residues, to the gas grid.
Now that the system has been operating for around a year, the objective of transforming the creamery operation by maximizing the production of biogas has been achieved with some impressive results, those involved with the project say.
The system is generating 5.35 Megawatt hours (MWh) of renewable energy of biogas, is treating 1,650m³ per day of process effluent and whey of biogas, producing around 1,000 Nm³ /hour of biogas, revenue for energy generated, and also reducing costs by cutting the fossil-based fuel purchase of biogas.
The on-site anaerobic digestion (AD) plant is funded and operated for First Milk by Lake District Biogas. They commissioned Clearfleau to design, build and operate the bio-energy plant.
Mixing is an essential part of the AD process and System Mix Ltd., who market the Rotamix Dual Zone Mixing System, supply mixing equipment to numerous projects undertaken by Clearfleau.
Early in 2015, Clearfleau undertook the initial upgrade of an existing anaerobic treatment plant at the Aspatria site, prior to starting the new AD plant.
System Mix said the success of the plants depends on a durable mixing technology supported by Vaughan Chopper pumps.
Andy Parr, director of System Mix, said it is crucial to the AD process that suitable pre-conditioning of solids is carried-out prior to digestion.
The Vaughan pump prevents re-accumulation of fibrous and fatty material in the digester and this means that material continues to pass through the nozzles, he said.