Valorization of sludge from drinking water treatment plants. A commitment to circular economy and sustainability

Waste products are generated In a Drinking Water Treatment Plant (DWTP) such as the sludge coming from, mainly, the phases of settling and filtration. Currently, this is becoming increasingly difficult due to the high volume produced and the shortage of disposal options. The objective of the present article is to incorporate the concepts of circular economy and technological nutrient in the valorization of the sewage sludge that is generated in a DWTP. In light of this, it is expected to give answer to the European Directive about circular economy, since the limited availability of suitable agricultural land for sludge application, as well as the risks of pollution of surrounding surface water and ground water bodies has made it necessary to reduce, and even to avoid, the discharges, including the sludge in the productive process as technological nutrient. This enables to use the sludge as basis for the development of additives in the ceramic industry and the production of cements, as well as to recover a fraction of the coagulant and flocculant to use them in the own process of a DWTP.