New slurry purification system starts operating at Welsh College

A dairy farm with a 500-cow herd could potentially make savings of nearly £50,000/year and reduce its risk of polluting watercourses by removing the water from slurry and purifying it, according to a Welsh farm trial.

Coleg Sir Gâr’s Gelli Aur Farm – a Farming Connect Innovation Site – is trialling technology that de-waters and purifies slurry, a £1.1m Prosiectslyri project funded by the Welsh Government through the Rural Development Programme.

The treatment plant at Coleg Sir Gâr’s Gelli Aur Campus is in its first week of operation and farmers have had an opportunity to see how it works and potential benefits of introducing the technology in their own systems.More than 250 farmers from across the UK attended the joint Prosiectslyri Project and Farming Connect open day.

The equipment at Gelli Aur is processing 35t of slurry daily and is already exceeding expectation.

The company behind the technology, Swansea-based Power and Water, had anticipated extracting 80% of liquid from the slurry, but is achieving 90%.

The purification process needs further work – the filtered water is not yet clean enough for discharge into local watercourses or to re-use on the farm, but this is within reach, says Gareth Morgan, Power and Water’s chief executive officer.

“We are refining the processes as we go along,’’ he explains. “The treated water does need analysis before being discharged. We are working with Natural Resources Wales to define discharge quality parameters.”

How it works

The system works by pumping slurry in its original form from the cubicle housing into a separator.

The solid material, a 10th of its original volume because the water has been extracted, drops into a storage area below the separator.

Once the holding area is full, this stackable material is scooped up and stored in a covered area, ready for spreading.