Study on the Composition and Environmental Impact of Sewage Sludge

Abstract

The article examinee the characteristics of sewage sludge and its impact on the environment. The description of technical installations, sludge sites in the municipal wastewater treatment systems, which are sources of unfavorable sanitary and epidemiological condition of the studied territory, was presented. A detailed analysis of the structure, composition and morphology of sludge sediment was given. It was found that the sludge presents a loose, rough heterogeneous porous structure represented by the presence of a fibrous substrate with amorphous scaly-crystalline inclusions. During laboratory analyses of the composition of the dry residue, the presence of such types of heavy metals as chromium, manganese, nickel, copper, zinc, lead, cobalt, molybdenum, cadmium was revealed. The excess of permissible concentrations of various elements was observed: chromium more than 7.1 at MPC – 6.0 by 1.18 times; copper more than 3.3 at MPC – 3.0 by 1.1 times; zinc more than 27.3 at MPC – 23.0 by 1.18 times; lead more than 34.3 at MPC – 32.0 by 1.07 times; cobalt more than 6.4 at MPC – 5.0 by 1.28 times; molybdenum more than 6.9 at MPC – 5.0 by 1.3 times. Soil analysis revealed a pH of 7.1, which is neutral, may be optimal for plants; the concentration of calcium, iron and chromium does not exceed the established maximum permissible values. When analyzing the air environment of the territory of the treatment facilities, the presence of gaseous pollutants, such as methane, ammonia, nitrogen dioxide, hydrogen sulfide, carbon monoxide, was established. It has been established that anthropogenic sludge landfills are the sources that create a technogenic load on the atmospheric air, polluting it with methane, since the concentration of methane exceeds the MPC by more than 3 times