Dewatering sludge from water treatment plants by microwave irradiation

The paper presents the physical characteristics evolution of sludge from Water Treatment Plants after microwave exposure. There were analyzed 2 types of sludge with different values of humidity (sludge from Voila Water Treatment Plant of Campina municipality and sludge from Rosu Water Treatment Plant of Bucharest municipality). The article presents the variation of dry solids content and humidity of the analyzed sludge depending on microwave exposure time. After the microwave exposure tests, the following results were registered: sludge from Voila WTP reduced its humidity from 79.14% (raw sludge) to 0.14% and sludge from Rosu WTP reduced its humidity from 45.38% (raw sludge) to 0.14%. Based on the obtained results, there were ellaborated formulas correlating energy costs for sludge dewatering with humidity variation for the analyzed sludge types.