Wastewater System: How Does It Work?
Secondary Treatment
The LRBSA treatment plants use the activated sludge process to provide secondary treatment. Wastewater entering the aeration tank is combined with activated sludge, a mixture of organic material and microorganisms.
Disinfection
The Throop plant uses liquid chlorine bleach to kill bacteria in the treated wastewater. A chlorine contact tank provides holding time the give the disinfectant time to react. The Archbald plant uses ultraviolet light to provide disinfection.
Sludge Treatment
Anaeorbic digesters at the Throop plant are used to break down organic material in the primary and waste activated sludge. "Anaerobic" means that there is no oxygen in the treatment tank.
Dewatering
The treated sludge, now called biosolids, is squeezed between the rollers of a belt filter press to remove water.
