Wastewater filtering from a metal polishing station for pollution prevention.

摘要

Wastewater effluent from grinding and polishing stations is a pollution concern at Sandia National Laboratories. Efforts to ensure that the effluent does not exceed City of Albuquerque grab sample limits have relied on traps and settling tanks which are ineffective, As an alternative measure, a pumped filtration system was tested to determine if metal concentrations in wastewater could be reduced to a level below the City of Albuquerque grab sample limits. A one micron cellulose filter was used in a commercial filtration pump to filter wastewater. Wastewater samples were taken from upstream and downstream of the filter during typical polishing operations, and the samples analyzed for seven different metal concentrations. The concentrations of metal in the wastewater after filtration were always below the City of Albuquerque discharge limits, sometimes by 2 orders of magnitude. This method of pollution prevention (ie. wastewater filtering) is both inexpensive and very efficient. Sandia National Laboratories facilities designers in combination with facilities maintenance personnel are currently retrofitting existing stations in the Metallography laboratory in Department 1822 and should consider installing this type of system with all new polishing facilities.