Strainpress® technology is playing a small but vital part in helping Sydney Water achieve its goal of making a number of improvements at its Malabar Sewage Treatment Plant (STP).

Among these improvements is the aim to upgrade the screenings collection, transfer and handling processes, the grit handling and transfer processes, the sludge digestion and the biosolids handling and transfer systems.

One of the major benefits will be an improvement in the quality of biosolids produced.

The Malabar STP, which processes nearly half of the city’s sewage through its primary treatment processes, produces about 33,000 tonnes a year of nutrient-rich biosolids – a soil conditioner/fertiliser which is used extensively to improve the fertility and structure of farming soils in New South Wales.

These biosolids can produce “green energy” in the form of biogas. Biogas can be used as a fuel; for any heating purpose; and in a gas engine to convert the energy in the gas into electricity and heat.

John Koumoukelis, a Director of Hydroflux Huber, said, “To increase the performance and efficiency of anaerobic digesters that process the biosolids, Hydroflux Huber supplied the Malabar STP with three HUBER Strainpress sludge screens.

“These Strainpress sludge screens have been operating for six months and are successfully removing unwanted screenings such as plastics, fine rages, cotton buds from biosolids, before its processed in the anaerobic digesters.”

Mr Koumoukelis said these materials would also block mixers, heat exchangers and sludge pumps that were installed within the digesters.

“These unwanted materials would otherwise accumulate within the digester, leading to a reduction in performance, maintenance headaches and a reduction in the amount of gas produced. 

“One of the major benefits of Strainpress is that it prolongs the need to put a digester offline for cleaning by many years – so the three sludge screens will make a major contribution to minimizing the maintenance costs at the Malabar STP,” Mr Koumoukelis said.

The Strainpress sludge screen is a pressure-fed inline system for screening any type of sludge, including highly viscous and greasy waste.

As evidence of its effectiveness, there are more than 1,500 successful installations of the HUBER Strainpress worldwide, with installations across most major Australian water authorities.

How the Strainpress works

The Strainpress increases the operating reliability of downstream sludge treatment systems, such as thickening, disinfection, stabilisation, dewatering, drying, and reduces maintenance requirements.

A pump presses the liquid through the screening zone and delivers it to further process steps or utilisation. The liquid is under pressure.

The coarse material, which is retained on the screen surface, is stripped off by a coaxial screw and pushed through the press zone where the material is extensively dewatered and compacted.

The compacted material is pressed through a gap around a hydraulically operated pressure cone which closes part of the pipe end and builds up counter pressure.

The system does not need any wash water as backwashing of the screen is unnecessary. The perforation and design of the discharge section are individually adjusted to optimally suit specific requirements.

The flow is under pressure as it streams through the Strainpress. It is therefore easily possible to integrate the Strainpress into the existing pipeline and automatic system.

This partner content is brought to you by Hydroflux Huber. A member of the Hydroflux Group, Hydroflux Huber is an Australian business dedicated to providing world leading wastewater technology and processes to water authorities and councils. In Australia, Hydroflux Huber exclusively represents HUBER. 

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Lauren brings a fresh approach to content. While she’s previously written for publications as diverse as Australian Geographic, The Border Watch and Girlfriend, she’s found her true passion in her current role as an editor in the world of energy and infrastructure trade magazines.

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