Green Lake, Wisconsin
Challenge
Chemical, biological treatment, or a combination of both, is the common method for removing phosphorus in a wastewater treatment plant (WWTP). When using chemical treatment, metal salts are added which react with soluble reactive phosphate (i.e., Orthophosphate) to form solid precipitates that are removed by physical processes such as clarification and filtration. The required chemical dosing rate depends on factors such as the targeted effluent phosphorous concentration, the influent phosphorus load and the amount of phosphorus that is being removed biologically.
Solution
The plant was upgraded with an OSCAR process performance optimizer control system with phosphorus controller, which uses continuous measurement of orthophosphate using a YSI IQ SensorNet P700 analyzer to automatically adjust the chemical dosing rate to maintain a desired effluent TP concentration without overdosing.
