Industrial Wastewater Pretreatment Evaluation
This industrial facility's previous National Pollutant Discharge Elimination System (NPDES) permit required that treated waste flowing from their facility meet a copper limit of 21 parts per billion (ppb) on a monthly average and 42 ppb daily maximum by the end of 2014. Although this facility's activated sludge wastewater treatment plant (WWTP) used at this time was capable of removing some copper biologically through co-precipitation, the WWTP could not meet these new limits without additional treatment. American Structurepoint worked with this industrial facility to explore multiple options that included the implementation of a copper treatment system versus modifying the existing lift station and installing a new force main to discharge to the local municipality’s sanitary sewer system. Due to overall project costs and the desire to stop treating wastewater, this industrial facility elected to connect to the local municipality.
The second portion of the project included replacing two existing suction-lift wastewater pumps and upgrading one existing suction-lift pump in order to pump all waste flows to a connection location on the City’s collection system. The new eight-inch-diameter force main is located along access roads, across open fields, and adjacent to a public use trail. Upstream of the connection to the municipal system, the force main transitions to a gravity sewer. With an approximate length of 7,200 lft and low flows during evenings and weekends, this project also includes odor control facilities. American Structurepoint designed a chemical feed system at the start of the force main to control potential odors due to long contact times in the force main. The odor control equipment is located in an existing building and required demolition of the existing screening equipment. Finally, a flow meter was installed to measure the amount of flow from this facility to the municipality for billing purposes as well provide flow-pacing capabilities for the odor control system.