SEEPEX SAI optimises dewatering plant 

Scottish Water’s Kinneil Kerse WwTW produces an estimated 4,701 tds of dewatered sludge which is conditioned with lime for use as fertiliser on land. The sludge operation at this site has been funded and is operated by Veolia who are contracted by Scottish Water. In 2021, as part of a modernisation project delivered by Veolia, two competitor’s progressive cavity (PC) pumps were installed to feed dewatered sludge into a SEEPEX lime mixing pump.

Blocked Pipework after Commissioning

After commissioning the new pumps, the site began to experience regular blockages in the discharge pipework which affected feeding the lime mixing process and sludge disposal. To clear the blockages the pipework had to be dismantled and the site incurred additional costs associated with the hire of a mobile lime dewatering unit. Veolia approached SEEPEX for a solution.

After assessing the installation, it was clear that the high friction losses generated when pumping 22-25 % DS sludge through 55m pipe length with a 3m. elevation including 3x 45° and 5x 90° bends were affecting the pumps’ performance.

To address this, SEEPEX offered a trial for their Smart Air Injection (SAI). SAI is an energy efficient system that combines a SEEPEX open hopper progressive cavity pump with pneumatic dense phase conveying technology. The system is able to transport 16-40% DS dewatered sludge up to 1,000m. with a lower operating pressure requirement than conventional technology.

Blockage Free Solution for Sludge Cake Transfer

SEEPEX UK installed and commissioned the trial SAI system to demonstrate its effectiveness. Within the first 30 minutes of operation, SAI had cleared out all existing blockages and continued to perform.

SEEPEX retrofitted the SAI system to the competitor’s equipment. This included: SEEPEX SAI controls and MB Air Systems’ compressor and air receiver, both companies being part of Ingersoll Rand.

The SAI system has proven to be robust and reliable overcoming the existing pumps’ performance issues, enabling the sludge to be processed for land disposal. In addition, SAI enables the discharge pipework to be emptied when idle, removing the risk of blockages, thus reducing downtime and maintenance costs.

Commenting on this project, Veolia said: “We were very happy to work with SEEPEX to get this SAI system installed. It has given our site a solution to a difficult issue and resolved it. We use this system daily and it is beneficial to our day to day working environment.”

Combined Service and Support

SEEPEX and MB Air Systems have joined forces to deliver mission-critical, energy-efficient and market-leading technology for conveying applications. Our conveying systems are fully supported by a trained team of Field Service Engineers for service, installation and aftermarket support. Together we offer our customers our combined experience and technical expertise, providing one interaction point and one contract – for a streamlined project.

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