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Why are grease and floating materials skimmed from primary clarifiers?
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wastewater treatment
All the sewers in your neighborhood end up here.
In wastewater treatment, grease and other floating materials are skimmed from primary clarifiers as part of the physical separation process.
While the primary purpose of these sedimentation tanks is to allow suspended solids to settle to the bottom as sludge through gravity, lighter substances such as grease, oils, and fats naturally rise to the surface. Mechanical surface-skimming devices are employed to remove these materials to prevent them from interfering with subsequent treatment stages, clogging downstream equipment, or negatively impacting the efficiency of the overall environmental engineering process.1