Current stage of knowledge relating to the use ferruginous sludge from water treatment plants – a preliminary review of the literature

In water treatment plants, a large amount of wastewater and sludge is generated during the processing of drinking water. The composition of the sludge is determined by the type and raw water chemistry, as well as the methods and materials used for purification. The major components of the sludge are iron and manganese oxyhydroxides. In the past, the sludge was landfilled, but for environmental reasons it became necessary to find uses for the sludge. The aim of this study was to identify examples of using this sludge. Nowadays, the sludge is applied in the treatment of municipal wastewater, agriculture, and the production of cement and bricks, among others. Attention was also paid to the possibility of using the water processing sludge in different sorption applications.