What does WAS stand for in wastewater treatment?

What does WAS stand for in wastewater treatment?

• A. Waste Activated Sludge (WAS)
• B. Water Activated Sludge
• C. Waste Air Sludge
• D. Warmed Activated Sludge

Answer: (A)

WAS stands for Waste Activated Sludge. In an activated sludge treatment process, microorganisms in the aerated mixed liquor grow and form biological flocs. To keep the amount of solids in the tank at the right level and to maintain the desired solids retention time, a portion of the sludge is regularly removed. This excess sludge is the waste activated sludge, or WAS, which is then thickened and treated separately before disposal or reuse. The other options don’t fit because they aren’t established terms in wastewater treatment: water activated sludge, waste air sludge, and warmed activated sludge aren’t used to describe the excess biomass produced by the process.

WAS stands for Waste Activated Sludge. In an activated sludge treatment process, microorganisms in the aerated mixed liquor grow and form biological flocs. To keep the amount of solids in the tank at the right level and to maintain the desired solids retention time, a portion of the sludge is regularly removed. This excess sludge is the waste activated sludge, or WAS, which is then thickened and treated separately before disposal or reuse. The other options don’t fit because they aren’t established terms in wastewater treatment: water activated sludge, waste air sludge, and warmed activated sludge aren’t used to describe the excess biomass produced by the process.