Superfund Innovative Technology Evaluation (SITE)
Note: EPA no longer updates this information, but it may be useful as a reference or resource.
|EPOC Water, Inc. Microfiltration
Technology Applications Analysis Report
EPOC Water, Inc.'s Microfiltration Technology uses precipitation, microfiltration and sludge dewatering to treat a variety of liquid wastes. The first step involves the chemical precipitation of heavy metals. Precipitates and all particles larger than 0.2 microns are filtered through a unique tubular textile crossflow microfilter (EXXFLOW). The concentrate stream is then dewatered in an automatic tubular filter press (EXXPRESS). The EXXFLOW microfilter modules are fabricated from a proprietary tubular woven polyester. Wastes pumped into the polyester tubes form a dynamic membrane, which produces a high quality filtrate and removes all particle sizes larger than 0.2 micron. This technology was demonstrated at the Iron Mountain Mine Superfund site, Redding, California, in May/June 1992 on metal laden acid mine drainage. Different alkalis such as Hydrated Lime (Calcium Hydroxide), Sodium Hydroxide (50% liquid caustic soda), and Magnesium Oxide (MgO) were used to precipitate metals from the solution. MgO was the most effective precipitating agent in this demonstration producing no detectable concentrations of metals in permeate samples as well as producing a filter cake with 30% solids. The filter cake passed the toxicity characteristic leaching procedure (TCLP) test for metals with leachable levels well below regulatory limits.