| 英文摘要 |
The objectives of this project were to establish the database of long-term physical and chemical characteristics of municipal solid waste (MSW) and to evaluate the variation of MSW composition and property by careful sampling, sample preparation and the analytical techniques. Meanwhile, the performance of this project could be also useful in adopting the strategies of MSW management, developing the innovative technologies of recycling and recovery, and assessing the safe technologies of MSW disposal.
According to the results of sampling and analysis, the major compositions of the MSW were paper, plastics, and food scraps. The composition content of the above waste was almost 93.62% of the total MSW. Paper products made up the largest component of MSW generated (39.42%, wet basis), and food scraps comprised the second-largest component (37.64%, wet basis). Plastics were also a major component in MSW. The average content of plastics was 16.56% (wet basis) of the total MSW in 2014. The contents of metals and glasses of the total MSW were 0.51% and 0.80%, respectively. Wood and yard trimming, rubber, leather, and textiles combined made up about 3.79% of MSW. The results showed that the variation of composition in paper and plastics were increased in the past three years. To compare the moving average (past three years) of paper and plastics composition, the paper and plastics content in MSW were increased slightly from 39.15% and 15.59% to 39.42% and 16.56%, respectively. That is, the composition of paper and plastics of MSW increased gradually in past three years. On the other hand, in this year, compositions of food scrap, metals, and glasses of MSW were lower than that of moving average (past three years). It can conclude that the compositions of food scraps, metals and glasses of MSW decreased gradually in past three years. Besides, the types of paper of MSW included office paper, newspaper, corrugated paper, paper bag, paper container, and paper for toilet products, etc. In this project, approximately 18% of paper for toilet products was found in MSW samples. The overall average moisture content in the MSW was found to be 55.17%. The combustibles made up an above 39.35% of the MSW on average due to the low content of metals, glass, and other inorganic components. The average lower heating value (LHV) was about 1870 kcal/kg. The analysis results of tested metals (Zn, Pb, Cu, Cr and Cd) in combustible of MSW indicated that the tested metals concentrations, Zn, Pb, Cu, Cr and Cd were 25.7 mg/kg, 7.27 mg/kg, 11.0 mg/kg, 9.41 mg/kg and 0.463 mg/kg, respectively. Based on observations of this project, it was concluded that a well-established database of MSW using the results of long-term sampling and analysis projects could reduce bias in results. This project also provided important information for consideration of strategies in MSW management.
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