WAT E R OP E RATIONS A ND TR EATME N T
HYDRAULIC MODELLING OF FLUSHER UNITS The Flusher is an innovative system that utilises the potential energy from the flow within the sewer to clean it. This outline is extracted from a case study undertaken by Atkins Global to assess the effectiveness of the Flusher units theoretically, using infoWorks CS.
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he Flusher units have been simulated in InfoWorks CS using the Real Time Control (RTC) functionality. The assessment has been undertaken on an example 225 sewer prone to siltation at four separate locations. The sewers where silt occurs have been laid at gradients of less than 1 in 300, while the average gradient of the whole branch is approximately 1 in 120. The study investigated the effects of locating the Flusher unit at five locations in the system and assessing the results. Under a dry weather flow, the greatest increase in velocity occurs immediately upstream of the Flusher unit and within the first 500m downstream. However, the units are responsible for an increase in peak velocity for up to 4km downstream. Furthermore, the increased velocity would be repeated for every operation of the Flusher unit which could typically be more than 50 times per day depending on the characteristics of the catchment. It was predicted that the Flusher will operate approximately 64 times in a day under dry weather flow conditions, therefore improving flow conditions by eliminating silt build ups.
The steps in assessing the benefits of a Flusher: • Review historic and ongoing jet cleaning costs • Undertake a hydraulic performance assessment of the location • Consider the effectiveness of various Flusher locations • Assess potential upstream surcharge risks • Evaluate downstream benefits • Develop a monitoring plan A cost-benefit analysis can be completed once the above information has been sourced, assessed and evaluated.
FLUSHER II A passive gate device for controlling and maximising hydraulic flow in sewers •
Reduces operational costs – No more water jet sewer cleaning – No more Silt & Debris removal – Less surcharge & blockages
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Installed in Maintenance Holes – Easy to install – Easy to maintain – For DN150 to DN450 sewer pipes Resistant to rag jamming and blocking Inherently “fail safe” during storms Data Logger and Telemetry Module – Know what’s happening and when
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+61 418 691 989 6/58 Box Road, Taren Point NSW 2229 Australia enquiries@aussietrenchless.com
www.aussietrenchless.com
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UTILITY • AUGUST 2021
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