News | September 24, 2013

New THK Hybrid Sludge Thickening System Eliminates Polymer Costs


Centrisys completely rethought the process to reduce costs, increase capacity, minimize footprint

Wastewater treatment facilities looking for a way to reduce or completely eliminate the cost of polymer now have a new solution: the THK Thickening System from Centrisys.

Centrisys Corporation, a technical innovator of dewatering centrifuges and dewatering systems, engineered the new THK thickening centrifuge to thicken waste activated sludge while requiring no polymer. The system’s patented Hydraulic Assist technology allows for a more efficient and controlled discharge of thickened sludge while reducing operating and maintenance costs – all in a footprint that’s up to 90 percent smaller than traditional technologies.

Eliminating Polymer Equals Faster ROI
Because of the THK’s polymer-free operation during the thickening process for WAS, wastewater treatment facilities can expect to save about $140,000 per dry ton of solids annually – with a return on investment of 2.5 years due to polymer savings alone. Compared to gravity belt or rotary drum systems, the THK offers the highest processing capacity for the lowest cost. It produces up to 8 percent cake solids while running at flow rates of up to 1,000 gallons per minute, per machine.

“When we started designing the THK, we asked ourselves: ‘What’s the biggest challenge treatment plants are facing with respect to the thickening process?’” said Centrisys President Michael Kopper. “Once we got to the heart of the issue – polymer costs – our team created a whole new system to solve it. The result is a more powerful, compact, efficient way for our wastewater industry customers to thicken sludge.”

Forward-Thinking Facility in Kenosha, Wis., Sees Fast Results
The THK installation at the wastewater treatment facility in Kenosha, which is known in the industry for advancing new ideas, will be among the highlights next month at the Water Environment Federation’s Technical Exhibition and Conference in Chicago.

Installed in August 2011, the THK has already saved Kenosha an estimated $80,000 to $100,000 in equipment upgrades that would have been required to the city’s aging dissolved air flotation system. The THK also saved a significant amount of space, taking up less than 1,000 square feet, compared to the two floors of a 10,000-square-foot building occupied by the DAF system.

Visitors to Booth #2619 at WEFTEC (, Oct. 5 to 9, can talk to Kenosha Water Utility officials and observe a demonstration of their installation in action. Assistant General Manager Dave Lewis will be on hand at 2 p.m. Monday, Oct. 7, while General Manager Edward St. Peter will be on hand at 2 p.m. Tuesday, Oct. 8 and at 1 p.m. Wednesday, Oct. 9.

How the THK Process Delivers Multiple Advantages
The THK delivers superior performance due to its revolutionary design. While thin sludge is fed continuously into the unit, a specially designed scroll pushes the solids toward the solid end discharge. Simultaneously, the clear liquid is forced in the opposite direction and discharged through energy recovery nozzles.

Combined with the hydraulic scroll drive and other custom design innovations, the machine’s power consumption is reduced; a THK unit operating continuously at 100 gallons per minute uses only 11 kilowatts per hour. The entire system is contained in an airtight enclosure, minimizing operator exposure to process liquids and vapors. This eliminates odors, as well as the need for aerosols or an air handling system in the thickening area, further reducing space requirements.

Typical applications for the THK Thickening System include:

  • Secondary (waste activated) sludge
  • Primary sludge
  • Oxidation ditch sludge
  • Digested sludge
  • MBR (membrane bioreactor) sludge

About Centrisys Corporation
Centrisys Corporation is a global innovator of decanter centrifuges, dewatering systems and other technologies for dewatering in both municipal and industrial applications. Since its founding in 1987 as an equipment service provider, the company has evolved into a technical leader, producing breakthroughs that continue to improve efficiency, safety, performance and more. Based in Kenosha, Wis., Centrisys is the only U.S. manufacturer of decanter centrifuges for municipal water and wastewater applications. For more information, visit

Source: Centrisys Corporation