Black & Veatch selects Sweco to design and commission DEMON at Knostrop plant in UK


Engineering, environmental and design consultancy Sweco has been selected by US-based Black & Veatch to design, commission and guarantee the de-ammonification (DEMON) process at Knostrop sludge treatment facility in the UK.

Located on Yorkshire Water, on the outskirts of Leeds, the sludge treatment facility will see Sweco utilise expertise developed in the Netherlands and will serve as the largest overall capacity DEMON project in the country.

Sweco technical director Philip Wiltshire said: “This technology will also provide Yorkshire Water with the option to make further energy savings through the implementation of mainstream DEMON in the coming years.

“Mainstream DEMON (also known as ‘cold anammox’) can offer energy savings of between 25% and 30% in activated sludge plant aeration systems, as well as improving the quality of effluent.”

Currently, the Knostrop sewage treatment plant is undergoing redevelopment works, led by Black & Veatch, to facilitate an enhanced and effective treatment of sludge on the site.

As part of the revamp project, Sweco will be responsible for designing, commissioning and guaranteeing the liquor treatment process at the facility.

While the design for the DEMON process is slated to be completed by April this year, the installation by Black & Veatch is expected to be concluded in March next year.

Co-ordinated by Sweco, the process commissioning of the sewage treatment plant is expected to begin in February next year and the plant will be handed over to Yorkshire Water in November.

For almost 100 years, Knostrop wastewater treatment facility has been treating sewage from domestic properties as well as industries.

Once installed at Knostrop, the DEMON technology will ensure the removal of 85% ammonia from liquors produced by the new sludge dewatering plant at the facility without any pH correction or carbon dosing.

Operating at maximum capacity, the plant will be able to remove 3,150kg of ammonia every day.


Image: Sweco UK to design and commission DEMON process at Knostrop sludge treatment plant. Photo: courtesy of Sweco.