A HUBER Technology Wastewater Case Study at Cannock STW for Severn Trent Water

HUBER Technology recently completed a project for Severn Trent Water at Cannock STW, north of Birmingham. HUBER Technology were engaged on the project in 2018 with the project being installed in late 2019 and commissioned in 2020.
 

Project Profile

This project was part of the upgrade to the Four Ashes and Cannock STW sludge treatment capability to include finer screens and provide sludge thickening.

HUBER Technology Supplied

• 2 x HUBER Sludgecleaner STRAINPRESS® 290 5mm Sludge screens including Control Panels to Severn Trent Water Specification and a 6m high gantry to mount the screens on.
• 2 x HUBER Sludge Gravity DrainBelt Thickeners DB 2.0 complete with polymer dosing system and thick sludge discharge pumps

Objective

The primary objective was to improve the sludge screening on site to prevent screenings that had bypassed the inlet works entering the downstream process, which included the new gravity belt thickeners.

Solution

The solution formed two parts, the sludge screening and then the sludge thickening.

The throughput required for the sludge screening was 60m³/hr at an incoming thickness of 2% D.S. Two screens were selected to allow for a duty / standby operation.

The screens were pre-installed onto the gantry in HUBER Technology’s UK workshop to allow the control panels to be fitted and cabled to the screens. This reduced the onsite installation time with the offsite fabrication and reduced the need for working at height on site.

For the sludge thickening, the sludge was a mixture of primary and SAS and the requirement for the throughput was 96.72m³/hr at a 1% D.S. with both thickeners in operation. A dry solids of >6% was required for the outlet.

Product Profile

• HUBER STRAINPRESS®– Sludge Screening – To remove solids and rags from imported municipal sludge prior to thickening or dewatering. Benefits include high solids removal, low energy consumption, 385 UK reference sites, simple robust design and fully automated operation.

• The HUBER Belt Thickener DrainBelt is especially designed for sludge’s with poor settling properties:

  • Minimised coagulant consumption due to efficient distribution
  • Constant thickening result due to the long sludge residence time on the filter belt
  • Increased thickening results due to a ramp installed to decelerate the sludge prior to being discharged
  • A variety of filter belt qualities to meet specific requirements

   

“Early involvement with NMCN the contractor through site visits and meetings enabled a proven solution to be designed for both the screening and thickening requirements; Severn Trent Water should hopefully see the huge benefit this technology brings to the downstream process very quickly.”
Richard Willis-Area Manager