The objectives of this project were to establish the database of long-term physical and chemical characteristics of 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 municipal solid waste 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 municipal solid waste were paper, plastics, and food scraps. The composition content of the above waste was almost 93.62% of the total municipal solid waste. Food scraps made up the largest component of MSW generated (40.42%, wet basis), and paper products comprised the second-largest component (37.98%, wet basis). Plastics were also a major component in MSW. The average content of plastics was 15.22% (wet basis) of the total MSW in 2011. The contents of metals and glasses of the total MSW were 0.49% and 1.17%, respectively. Wood and yard trimming, rubber, leather, and textiles combined made up about 3.43% of MSW. The results showed that the variation of composition in paper and plastics were decreased in the past 10 years. However, the amounts of paper and plastics of the total MSW decreased significantly that resulted in amounts of MSW collection decreased in past decade. Meanwhile, the compositions of food scraps, metals and glasses of MSW decreased gradually every year. On the other hand, 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 from MSW sampling was paper for toilet products. The overall average moisture content in the MSW was found to be 55.61%. This is due to the high moisture content of the food scraps fraction. The combustibles made up an above 40.07% 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 1844 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 27.0 mg/kg, 16.4 mg/kg, 9.01 mg/kg, 9.09 mg/kg and 0.297 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 regarding consideration of trend in MSW management.
useful in adopting the strategies of municipal solid waste management, developing the innovative technologies of recycling and recovery, and assessing the safe technologies of MSW disposal.