Purifying waste water containing organic pollutants e.g. pesticide including urea, comprises contacting water with new activated carbon powder, and flocculating the liquid filled with activated carbon powder

摘要

The process comprises contacting water to be treated with new activated carbon powder, and flocculating the liquid filled with activated carbon powder. Each step of the process is continuously operated in different treatment areas. The partially used activated carbon powder is recycled before the flocculation step. The partially used recycled activated carbon powder: is prior mixed in aqueous suspension with a coagulant before added to the step of contacting with water to be treated; and is reintroduced in step of contacting new activated carbon powder with water. The process comprises contacting water to be treated with new activated carbon powder, and flocculating the liquid filled with activated carbon powder. Each step of the process is continuously operated in different treatment areas. The partially used activated carbon powder is recycled before the flocculation step. The partially used recycled activated carbon powder: is prior mixed in aqueous suspension with a coagulant before added to the step of contacting with water to be treated; is reintroduced in step of contacting new activated carbon powder with water and between step of contacting new activated carbon powder with water and flocculation step; and results from a separation step following the flocculation step. The process further comprises a preliminary step including a step of settling, preoxidizing, filtering, depositing, flotation, disinfecting and/or chlorinating.