Sewage treatment works upgrade

Siltbuster’s specialist teams responded within 24 hours when a customer faced flooding challenges while carrying out works to support a major Sewage Treatment Works upgrade.

The customer, a valued Siltbuster client, encountered a high water table while delivering a groundworks package to support works being carried out at a Sewage Treatment Works.

We were contacted by teams from national pumping solutions specialists Selwood, Siltbuster’s sister company in the Workdry International Group, who were working at the site, and identified that surplus groundwater needed to be treated before it could be safely discharged to a nearby watercourse.

The underground geology at the site was clay, and so attempts at passive treatment techniques were not providing sufficient treatment.

There were significant levels of solids present in the groundwater, so a solution was needed that would remove non-settling clay particulates.

Within 24 hours of being contacted, a Siltbuster Technical Sales Engineer attended site to have a look at the job. Samples taken from site were tested by Siltbuster’s laboratory to assess the composition of the wastewater, the contaminants present and the best treatment solution.

After analysis it was decided to treat the floodwater with clear chemical dosing, using a coagulant and flocculant to bind particles together so they could be separated out of the fluid.

Given the flow rate of circa 40m3/hr, a Siltbuster MT8 mix-tank was selected to allow for the coagulant and flocculant dosing. This resulted in the agglomeration of those non-settling clay particles which could now comfortably settle under gravity.

We partnered this mix-tank with two Siltbuster HB40R lamella clarifiers. These modular lamella clarifiers are used to retain agglomerated clay, which results in visually clear water being discharged to the environment. We also included a carbon dioxide dosing skid which would automatically neutralise any alkaline conditions which may arise.

To help deal with the levels of solids present, the rake drive included in the HB40R rake drive ensured sludge was agitated and could be easily drawn off with the provided sludge pumps.

Finally, Siltbuster provided two Peristaltic sludge pumps, complete with auto-de-sludge panels. This allowed the sludge to be automatically drawn off at inputted, scheduled timed intervals.

Siltbuster’s solution resulted in clear water being discharged to the environment. The client now has peace of mind that any water they pump through the Siltbuster system will be clear of suspended solids which means that they can continue work without worrying about any silt pollution in the watercourse.