Methods for urban wastewater sludge treatment

Objective: to identify the main technological approaches for treating urban wastewater sludge that will enable production of marketable products and generation of economic benefits. To present sludge treatment methods that, in addition to producing marketable outputs, will prevent environmental contamination. To justify the selection of technological schemes for sludge treatment in accordance with current legislation, taking into account the impact of liquid effluents released during treatment on the operational efficiency of municipal sewage treatment plants. Methods: a comprehensive analysis and systematization of existing regulatory documents concerning the treatment, disposal and elimination of sediments generated during urban wastewater treatment were undertaken. A comparative assessment was conducted of the effects that various sludge treatment technologies exert on the mechanical and biological treatment facilities of municipal sewage plants. Results: contemporary criteria for evaluating the effectiveness of technologies for treating and disposing of urban wastewater sludge were considered. A minimal required sequence of sludge treatment stages has been proposed to prevent adverse environmental impacts during both sludge treatment and disposal. The principal modern structures and devices for sediment processing, have been identified, which, both immediately upon implementation and over the long term, will contribute to improving the environmental performance of municipal sewage plants. Devices and structures suitable for modernization and/or reconstruction have been identified. Their upgrade will permit the production of market-demanded products at the final stages of the sludge-processing chain. Practical significance: the findings reflect current trends in sludge management, evidencing a shift from the obligatory basic dewatering toward opportunities and imperatives for generating revenue from sludge disposal. The proposed measures to improve sludge disposal efficiency at municipal sewage treatment facilities, based on best available technologies, will minimize adverse environmental impacts. The proposed technological schemes for processing sediments from urban treatment facilities will ensure compliance with contemporary environmental safety requirements while maintaining economic efficiency.