Thames Water

Increased sludge management and effective odour control with Zickert scrapers.

When Thames Water, the UK’s largest water and waste water services provider, wanted to make sludge management more efficient and improve odour control at its plants, it opted for Zickert bottom and surface sludge scraping equipment as its chosen solution. The overall project covers a total of 53 settling tanks in the Beckton, Crossness and Mogden sewage treatment works.

The challenge
Thames Water wanted to increase the waste water treatment capacity, improve operational efficiency and reduce odours at three of its largest treatment plants.

The solution
As its chosen solution, Thames Water opted for our Z2000 Zickert Bottom Sludge Scraper, which provides continuous sludge transportation, and the Z3900 Zickert Surface Sludge Scraper, which is an effective tool for removing surface sludge without taking any unnecessary transport water away with it.

Beckton STW
At the Beckton plant, the site of the largest project, the Zickert system was already in use in eight tanks. Now a further 24 existing settling tanks are being equipped with new Zickert scrapers. The installation, which involves a total investment of 16.5 million pounds sterling, covers an area of more than 56,000 square metres – which equates to around eleven football pitches. The project was assigned to Nordic Water’s British distributor, Hydro, via the main contractor GBM.

Mogden STW
At the Mogden plant, Zickert systems are being installed in five new tanks and retrofitted in eight primary sedimentation tanks. This is part of a Thames Water upgrade scheme designed to increase the waste water treatment capacity on site by 50%. The contract was awarded by Black & Veatch.

Crossness STW
Eight new primary sedimentation tanks are being built at the Crossness plant. This investment is part of an upgrade worth 220 million pounds sterling which aims to increase the waste water treatment capacity by 44%. The Zickert systems enable energy-efficient odour reduction and collect up sludge that can be used to meet 20% of the plant’s own energy requirements. The contract was awarded by Tamesis.

The result
Zickert offers major advantages over conventional sludge scraping technology. Thanks to its design, operating and infrastructure costs are low, and it also collects up more sludge than conventional scrapers. Moreover, less secondary treatment is required and Zickert produces more primary sludge with a higher calorific value when incinerated.

And since the ceiling height required for Zickert is much lower than for rival scraper solutions, less air needs to be processed to eliminate odours, which boosts processing efficiency.

Technical data
Investor: Thames Water
Plants: Beckton, Crossness and Mogden sewage treatment works

Beckton STW:
24 existing settling tanks are being retrofitted with new Zickert sludge scrapers.
Eight existing primary tanks already feature the Zickert system.

Mogden STW:
New Zickert sludge scrapers are being retrofitted in eight existing primary sedimentation tanks. Five new tanks are being equipped with new Zickert sludge scrapers.

Crossness STW:
Eight new primary sedimentation tanks are being built and equipped with new Zickert sludge scrapers. Capacity is being increased by 44%.