Exergetic assessment of municipal solid waste management system in south Beijing

The exergetic analysis model of municipal solid waste (MSW) was established to study the MSW management system in south Beijing. The materials and energy inventory of different processes, including transport, mechanical separation, compost, incineration and landfill, were analyzed. Based on the inventory analysis, the exergetic efficiencies of different unit technologies and management systems were studied, and the main results were: (1) the exergetic efficiency of compost and incineration is 5.98% and 14.23%, higher than landfill, 2.92%; (2) mechanical separation increases the exergetic efficiency of unit technologies, from 2.92% to 4.33% of landfill and from 14.23% to 15.59% of incineration; and (3) integrated treatment increases the comprehensive exergetic efficiency of the MSW management system, exergetic efficiency of MSW management system in south Beijing increased from 2.91% to 4.57% because the processes of mechanical separation and compost were introduced, furthermore, when the incineration facility is applied to treat the plastic and paper, exergetic efficiency of the system will increase to 13.95%. According to the exergetic analysis, HRRIS aims (harmless, recycling, reductive, industrializing and socializing) of MSW management system were put forward, and scavenger management, charging mechanism and integration of technologies were discussed.