Severn Trent captures carbon from sewage treatment

Severn Trent has utilised carbon capture technology in sewage treatment processes to create a sustainable fertiliser from waste.

The company partnered with CCm Technologies to use captured carbon dioxide to stabilise nitrogen, phosphates and organic chemicals contained in waste and turn it into plant nutrients.

The project at Severn Trent’s plant near Birmingham represents the first time the technology has been applied to the wastewater treatment process.

Rich Walwyn, head of asset intelligence and innovation at Severn Trent, said the first batch of the “super fertiliser” is ready from the project, which is partly funded by the Department for Business, Energy and Industrial Strategy’s (BEIS) Industrial Energy Efficiency Accelerator (IEEA) programme.

“Using carbon capture technology, we’re able to treat waste in a much greener and more efficient way than ever before, as well as getting a fantastic product at the end, which has carbon locked into it,” he said. “This new approach has taken us a step closer to making sure absolutely nothing is wasted, in the sewage treatment process.”

The IEEA programme supports commercial scale demonstrations of novel technologies with the potential to reduce energy consumption and carbon emissions, and accelerate their uptake in industry.

Severn Trent said the scheme would create new commercial opportunities as well as contributing to its 2030 net zero ambitions.

At present, the company generates the equivalent of half the energy it requires from renewable sources, predominantly anaerobic digestion and biogas. The carbon capture technology would bolster its efforts in this area and help it achieve its triple carbon pledge of 100% renewable energy, net zero emissions and an electrified vehicle fleet by 2030.

CCm’s technology converts captured carbon dioxide and other waste streams into stable value-added materials with multiple uses, including fertiliser.

Pawel Kisielewski, chief executive at CCm, added: “Our ability to capture the data generated by the process, that is central to the manufacture of this fertiliser, means we know exactly how much carbon, and the volume of nutrients recovered and placed back into the ground. This transparency and understanding bring integrity to the solutions being adopted by Severn Trent and make us all better aware of how effectively we’re tackling the climate crisis.”