Manganese removal is conventionally done by physical-chemical treatment. It involves chemical oxidation of manganese producing an insoluble manganese oxide. This oxidation is following by retention on granular material such as sand.
Unlike conventional treatment, which requires addition of a strong oxidant (potassium permanganate, chlorine or ozone) to obtain sufficient oxidation, the Mangaflo™ process developed by Veolia Water Technologies provides manganese treatment with an ecological aspect. Indeed, oxidant addition is no longer required because the process uses the manganese dioxide catalytic effect.
Water is filtered on a thick layer of manganese dioxide which acts as a catalyst and as an oxidant with the dissolved manganese in the water to be treated. So, the treated water complies with drinking water standards, with a residual manganese rate in the effluent lower than 5-20µg/l, depending on its design.
Mangaflo™ Plus is based on the same principle with an essential iron oxide layer added for arsenic removal. This materiel acts as an adsorbent. According to installation treatment capacity, filtration is carried out with an open or pressurized filter.
This process is composed of three filter media layers:
- An upper layer composed of iron hydroxide grain;
- An intermediate layer composed of sand and/or anthracite
- A lower layer composed of manganese dioxide.