Performance of three alternate arsenic removal technologies was evaluated in the laboratory. These were: (i) removal system based on alum and iron coagulation; (ii) removal system based on sorptive filtration using iron coated sand filter, and (iii) removal system based on sorptive filtration using gravel bed containing iron sludge. Based on laboratory performance, two technologies, ferric chloride coagulation, and sorptive filtration through iron-coated sand, were selected for the development of household arsenic removal units. The ferric chloride based unit is similar in design to the bucket treatment unit developed by DPHE-Danida. It involves precipitation of arsenic by adding a packet of coagulants to 25 liters of tubewell water and subsequent filtration of the water through a sand filter. The unit based on iron-coated sand has a pre-treatment system for removal of excess iron. This consists of a bucket where water is poured and stirred for sometime to accelerate precipitation of iron. The water then flows through a sand filter where the excess iron is filtered out. Finally th
To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.