Purcellville, Virginia, a short commute from Washington, D.C., is one of the fastest growing counties in the nation. To accommodate this explosive growth, the City of Purcellville needed to increase its water production. The City was tasked with designing a new groundwater treatment plant to supplement the town’s existing system. After reviewing several treatment options, the City and Engineer chose to work with Tonka Water to customize a design for a 200 gpm plant.
The treatment process consists of chlorine and potassium permanganate addition for chemical oxidation of iron and manganese, followed by filtration using a dual-media filter bed of manganese greensand and anthracite. The anthracite removes the larger iron and manganese precipitates while the greensand removes the smaller manganese dioxide solids that slip through the anthracite.
The treatment system is controlled by one PLC-based NEMA 4 automatic control panel, which automatically backwashes the filters upon loss of head, timer or operator initiation. The duration of the backwash is adjustable by the operator through an Allen-Bradley PanelView 1000 color touchscreen OIT.
The raw water analysis as summarized reflects moderate concentrations of iron and manganese existing in the water. The treatment process has been highly efficient in delivering high quality water as indicated.
|Iron (Fe)||0.15 mg/L||0.01 mg/L|
|Manganese (Mn)||0.25 mg/L||0.002 mg/L|