WATCH OX MN

High performance advanced catalytic media for removal of iron, manganese, arsenic and hydrogen sulfide

Product and Process Description

WATCHOX MN is a specially formulated, 20x40 U.S. Mesh-size granular manganese dioxide media possessing exceptionally high oxidative properties, making it ideal for the treatment of groundwater for potable water at very high surface loading rates (4-15gpm/sq ft) for the removal of iron, mangenese, arsenic and hydrogen sulfide.

The high catalytic activity and adsorptive capacity of the medias enables the processing of very high flow rates in small diameter filters, resulting in significant savings in plant size, real estate and supporting infrastructure. Unlike other traditional filter medias, the primary mechanism of removal is adsoption of the oxidized species on the external and interstitial surface of the media as opposed to physical filtration, thereby making contact tima an important design considerattion. Waters containing high iron and manganese concentrations can be effectively treated by increasing the contact time to yield the desired filter run interval, thereby reducing the frequency of backwash. The raw water containing the dissolved contaminants is first contacted with chlorine as the pre-oxidant, wich serves to oxidize the iron and manganese and convert them to their hydroxide and oxide form respectively while also serving to maintain the media in a continously high oxidative state. Oxidized manganese adsorbed on the surface of the media further acts to accelerate the conversion of iron to ferric hydroxide, which is also simultaneosly adsorbed.

For arsenic removal, the pre-oxidant converts arsenite to arsenate and iron in the water is converted to ferric hydroxide which adsorbs the arsenate to form ferric arsenate (a benign non-hazardous precipitate) which is adsorbed on the media. In iron deficient waters, iron in form of ferric chloride is added to effect the formation of iron hydroxide. Hydrogen sulfide is readily converted to elemental sulfur to produce an odor free effluent.

At breakpoint (that point at which the desired treatment objective is reached), the media is backwashed at a high rate for a short duration prior to returnung the media to the service mode. WATCHOX MN is used in traditional vertical or horizontal single or multi-cell pressure filters and is the only media required to effect treatment. Backwashing can be effected with either raw or treated water. With exeptional hardness and abrasion resistant characteristics, the media has a service life in excess of ten years with minimal attrition losses. With a multitude of installations ranging in capacity from 50gpm to 12mgd for the removal of the aforementioned contaminants, WATCHOX MN is rapidly gaining increased prominence as the media of choice based on its outstanding service life, robustness and vast oxidative potential.