Sediment Removal

Sediment accumulation in sewer pipes causes:
  • Restricted flows
  • Sewer blockages and overflows
  • Increased pump head, pumping cost and thus Greenhouse Gas Emissions

Sewer sediments are costly and labour intensive to remove.

Biosol products stop the formation of the biofilm glues that entrap sediments. Stopping the production of these glues (polysaccharides), enables the scouring of sediments in sewer catchments by normal water velocities. These sediments end up at the treatment plant, which means that they need to be managed as part of the normal sludge decanting process.

Where water scour velocity exceeds 0.6m/s and are sustained long enough to remove significant levels of sediment from the sewer pipe, sediment removal will occur more quickly and will be more complete.

It has long been known that jetting sewer pipes will remove the biofilm / sediment complexes, which in turn minimises sewage odour while improving the hydraulic efficiency of the sewer main. Improving the hydraulic efficiency of the sewer main reduces pumping energy, cost and greenhouse gas emissions.

The cost and disruption from jetting sewer mains and using induction trucks to remove the sediments is very high, preventing their wide-scale use. Additionally once the jetting is complete, the biofilm / sediments begin to reform in the sewer main.

Biosol products remove the biofilm / sediments as effectively as jetting, however unlike jetting, Biosol products prevent or minimise the reformation of the biofilm / sediment matrix. This ensures the maintenance of improved pumping efficiency, decreased cost and greenhouse gas emissions.

The rate of release of these sediments is controlled by the Biosol dose rates.

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