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Biosolids are the Sludge Generated by the Treatment of Sewage

2007 (approx.)

Detailed Description

Biosolids are the sludge generated by the treatment of sewage at wastewater treatment plants (WWTPs). WWTPs produce a variety of biosolids products for agricultural, landscape, and home use. Depicted in the diagram is an activated sludge tank at a wastewater treatment plant (upper left) and a holding area for biosolids (lower right).
(The two photos are not from the same facility.).


Public Domain.