چكيده به لاتين
Sludge management processes account for approximately 60% of the total cost of a wastewater treatment system. Therefore, it is necessary to implement a management plan that seeks to find the right method of disposal with the beneficial use of sludge. The sludge treatment process of municipal wastewater treatment plants generally involves complex and complex processes that do not make it easy to choose the best system. Therefore, a sustainability assessment method that covers all of the above seems necessary. In this research, first, using the upgraded SWOT matrix, the superior strategy of using treated sludge is determined. All possible options for achieving this strategy are then determined and constrained by the decision tree. The final options selected are evaluated by the modified AHP evaluation method for sustainability, in order to select the best and most stable option available from them. In this way, it is used by expert experts and under different script writing. For this purpose, strategies for using sludge including incineration, burial, use in construction, road construction and use in agriculture were selected. In this study, the results show that the best strategy for final disposal is its use as fertilizer for agriculture. Also, the sludge management method to achieve the final disposal is a combination of three stages of concentration, stabilization and dewatering, to concentrate the three methods of gravity filtering, air flotation process and centrifugation process, and to stabilize the two methods of compost and anaerobic digestion and to dry the sludge. The method of pressurized strip filters and drying sludge substrates was considered. In order to deliver the quality of the produced sludge for agricultural use, 6 options were finally selected. These options are all a combination of three parts: sludge concentration, stabilization and dewatering, which continuously improve the quality of the produced sludge. Then, to evaluate the sustainability of these options, a multi-criteria evaluation structure including 4 economic, social, environmental and technical criteria and 36 indicators were constructed by exploiting experts and also studying similar sources and the necessary weights were made. The results showed that among all the options, centrifugation process, anaerobic digestion and pressurized strip filters were suitable for condensation, stabilization and drying processes with 97.08%, followed by gravity process, anaerobic digestion and pressurized strip filters, respectively, for the process. Stabilization and drying with 2.87% were selected as the second option.
Keywords: Sustainable sludge management, Wastewater treatment plant, Multi-criteria evaluation, SWOT matrix.
