Removal of Arsenic from Waste Water

The fundamental, study was carried out in order to find out the opitimum conditions or the effective addition agents for the removal of arsenic from the waste water. The results indicate that the As content in the solution is reduced to about 0.1 ppm for the range of pH 3-8 by treating with 5 times Fe+++ salt as much as As content in original solution, when As is present as H3AsO4. In case of AsO2-, however, more than 15, times Fe+++ salt as much as As is needed between 6 and 9 in pH value to reach the sEme As level in the solution. Al and Mg salts were found effective for As elimination in H3AsO4 solution at the appropriate pH, but not satisfactory in As02-solution. The use of Ca (OH) 2 together with Fe+++ salt substantially reduced the amount of Fe+++ salt to be used for the removal of As at the same level.