Arsenate removal from drinking water by application of pelletized iron(hydr)oxides

Abstract

In drinking water production iron sludge is formed, either by aeration of groundwater, or as a result of the addition of coagulant (e.g. FeCl3) to surface water. For the Netherlands this means a yearly production of 80,000 tons of iron sludge. Iron(hydr)oxide is known for its good adsorption capacity for arsenate, phosphate and sulfide. However, large scale application is hindered by the high water content of iron sludge (70–90 weight %), which causes problems in transport and handling both in the supply chain and by the customer.