Arsenic Removal Technology

Ground water contains soluble Iron, toxic substance like Arsenic and may also contain pathogenic bacteria due to some external reasons. Hence to supply safe drinking water to the rural population, a suitable and sustainable process has been selected so that the plant can easily be operated and managed by the semi-skilled/unskilled villagers by their own.

The process has been designed to remove Suspended Solid, Iron, Arsenic and Bacteria from the raw water to the desired level for potable use.

The raw water from the bore well is fed to an Oxidation Chamber filled with Oxidising media Manganese Dioxide in downflow mode for the oxidation of the soluble Iron present in raw water. MnO2 catalyses the reaction between the Iron and Oxygen to convert Ferrous Bicarbonate into the precipitate of Ferric Hydroxide.

Water from the Oxidation Chamber along with the precipitate of Ferric Hydroxide is passed into a Sand Filter containing graded Sand on the graded Gravels. The precipitate of the Iron get settled in the Sand Bed and the water becomes free from Iron and other suspended solids.

The water free from Iron and Suspended Solids now flows into an adsorption tower filled with adsorbent AdsorpAs® in downflow mode. While percolating through the bed of the adsorbent, the soluble Arsenic present in water get adsorbed on to the surface of the AdsorpAs®. As a result the concentration of Arsenic both trivalent and pentavalent present in water get reduced to less than the permissible limit.

The water free from Iron, Arsenic and Suspended Solids is now passed to the overhead tank through UV steriliser capable of emitting UV of the germicidal range to kill any harmful microorganisms present in water.

The purified water from the over head tank may now be drawn through the tap for drinking and cooking.