The wastewater contained over 4,000 ppm of mercury and 400 ppm of selenium that required the use of tight pH control and metal precipitation. The process control used a proportional ORP system in conjunction with the IE-061 metal precipitant to meet the required ORP set point, assuring that all of the metals were precipitated. The precipitated wastewater was then flocculated using Floccin-B and then dewatered with a plate & frame press. The effluent wastewater (filtrate) was continuously online monitored by an XRF analyzer that verified metal limits to be below the discharge limits (below 1 ppm for mercury).
The skid mounted 10 gpm system was custom designed and manufactured by I.E. to fit through a standard 34-inch door opening so the unit could be located inside the sealed nerve gas containment room. The system was manufactured from fiberglass and special performance resins to withstand a low pH of 1.0 as well as high chloride levels. Operators in the facility main control room monitored operation of the unit remotely.