SLUDGE MANAGEMENT IN WATER TREATMENT PLANTS

Building new water treatment plants (WTP) as well as rebuilding, enlargement and modernisation of the existing ones must also concern technology and sludge management objects, including the possibility of managing them outside the WTP. The study identifies design and operating problems which have to be solved in the investment process. It also presents the technology of sludge processing designed for the WTP in the city of Rzeszow and the study results of the effects obtained during WTP starting. It was proved that the assumed ecological effect of limiting the concentration of slurry discharged into the Lubcza River (S(z) < 35 mg/dm(3)) and the effect of technological dewatering ranging from 24 to 47% d.m. were obtained. The dewatered sludge is a granulated product with a high proportion of mineral parts (above of 75%). It does not absorb water and does not putrefy while stored in the open air. After cementation it can be utilized for building purposes. Taking into account the sludge fertility values (river loess sludge), we should not dismiss the possibility of environmental or agricultural sludge utilisation after its storage or hygienization, which should eliminate sludge poisoning with Salmonella bacteria.