Severn Trent improving on biosolids offer for farmers

By swapping contractors for an in-house team, and offering better quality cake, Severn Trent is signalling a step change in its biosolids offering.

Bioresources logistics manager for Severn Trent, Joseph Stack, explains that the company has insourced the Farm Liaison team. “We’re now able to talk directly to farmers about what they want and have invested in our team and processing,” he says.

Investments include two upgraded sites, the Minworth Sewage Treatment Works near Sutton Coldfield, where the Thermal Hydrolysis Plant heats sludge to 170°C before applying pressure – both sterilising and shattering the cell structure of the bacteria in the sludge.

Following this process large digesters then biodegrade the solid matter within the sludge and produce methane-rich bio-gas, which supplies homes.

Finally, the sludge is taken through a dewatering process, where it is thickened and made ready for farmers to use.

“By improving the process, we now have a better-quality product that stands better in the field and can be classed as an ‘enhanced’ Biosolid,” explains Stack.

“I’d encourage any farmers considering using biosolids to get in touch with one of our farm advisers. They’ll visit your farm, review cropping types and rotations, look at your soil type and structure and make a recommendation that’s bespoke to your farm. The recommendation also breaks down the value to your farm; what it would save in fertiliser costs and what benefit you could see from the organic matter,” says Stack.