ABSTRACT
Biosolids thickening (or concentration) is a unit process used to increase the solids content of the biosolids by removing a portion of the liquid fraction. In other words, biosolids thickening is all about volume reduction. Biosolids thickening calculations are based on the concept that the solids in the primary or secondary biosolids are equal to the solids in the thickened biosolids. The calculation for estimation of the required biosolids pumping rate provides a method to establish an initial pumping rate or to evaluate the adequacy of the current pump rate. It is primarily water that has been removed in order to thicken the biosolids and result in higher percent solids. In this unthickened biosolids, the solids might represent 1% or 4% of the total pounds of biosolids. But when some of the water is removed, those same amount solids might represent 5–7% of the total pounds of biosolids.
