In the summer 2018 issue of the Clean Water1 CWEA magazine, we introduced the 6Ps model system (Products, Processes, Pollutants, Pretreatment system, Parameters, and Plan of the shop) for facility inspections. Each “P” is an integral piece affecting the other Ps. In other words, a change in one of those Ps triggers a change in another P. The most important P is the pretreatment system (PTS).
In this article, we will discuss wastewater treatment considering the Best Practical Technology (BPT) and Best Available Technology (BAT), terms used by the Environmental Protection Agency (EPA) when addressing effluent limitations. We will be examining the components of an industrial wastewater pretreatment system while explaining both control technology, BPT and BAT. Understanding of this wastewater control technology is paramount and would help metal finishers meet their effluent limitations2. Implicit in our discussion is that wastewater being treated is the rinses from the many metal finishing processes; a PTS will not treat concentrated process wastewaters economically.