Study On Pollution Property Of MSW In Songtao Reservoir, Hainan Province

Songtao reservoir locates in mid-west mountainous area of Hainan province. It is a catchment area between several Watersheds,such as Limu mountain, Boduo mountain, Xianpo mountain ,Hong mountain ,Shamao mountain and Songtao dam. After a long term monitoring, it indicates that the water quality of Songtao reservoir mainly remain the standardâ…¡of surface water while the minorities are the standardâ…¢. The water quality of drinking water source is under threat. In recent years, the MSW is becoming one of the main pollutants that influence the water quality. To protect the water quality safety of Songtao reservoir, the study on the pollution property and countermeasure for prevention and cure of the MSW of Songtao reservoir must be developed.By field survey and sample analysis, the production characteristics, physical and chemical properties and toxicological characteristics of MSW in Songtao reservoir are tested. By the static leaching experiment of MSW of Songtao reservoir, the leaching rules of MSW pollutants are analyzed. By way of verification of fitting curve, the leaching rule models are constructed and pollution properties of MSW are studied. According to the result of investigation and research, the countermeasures for prevention and cure of MSW in Songtao reservoir are suggested.According to the survey, MSW of Songtao reservoir can be divided into the following categories: MSW of town, MSW of farm, MSW of country. MSW outputs per capita of towns, farms and countries are respectively 0.74 kg·d^-1, 0.61 kg·d^-1and 0.16 kg·d^-1. The managements of the three types are different. MSW of town and farms implements the centralization of collecting-transporting-dumping. MSW of country is mainly discarded, and the rest part is for family cultivation, recovery and utilization.By sampling analysis, the organic matter content of MSW in Songtao reservoir is a little bit high, especiallythe content in farms is 47.26%.The content of glass and plastic matter is also high, the contents of organic matter, moisture content, pH, TN, TP, TK, As, Hg and Cr of MSW in Songtao reservoir are within the National MSW Control Standard for Agriculture. Whereas the content of Pb and Cd in MSW of towns and Cd in MSW of farms are a bit higher than the standard, after the treatment of selection, MSW in towns and farms can be used for agriculture. By the leaching toxicity of waste, Hg, Cd and Pb were not detected in MSW of town, the content of As and Cr of MSW in town are all below the leaching toxicity identification value. Therefore, MSW of the reservoir contain no harmful and toxic solid waste.The result of static leaching water-changing experiment indicates that the leaching rules of CODcr and BOD5 in MSW can be approximately described by Exponential models, and the leaching rules of TP, NH₃-N and TN in MSW can be approximately described by Logarithmic model. The pollutant concentration in leaching liquid of MSW is the daily release amount of pollutant in MSW. The pollution loads is the leaching velocities of pollutants. By way of verification of fitting curve, the leaching rule models are deducted and the leaching velocities of pollutants in MSW are calculated. The temperature influences the leaching velocity on some extent, but not much; pH has a little influence on the leaching rules of CODcr and a remarkable influence on the leaching rules of BOD5, TP and TN.The result of static leaching no-water-changing experiment indicates that the leaching rules of CODcr and BOD5 in MSW can be approximately described by Exponential model. And the leaching rules of TP, NH₃-N and TN in MSW can be approximately described by Cubic model. The daily pollutant concentration in leaching liquid of MSW is accumulated by the release amount of pollutant in MSW. By the derivation of fitted equation,the leaching rule model are deducted and the leaching velocities of pollutants in MSW are figured out. The temperature influences the leaching velocity of CODcr, BOD5, NH₃-N and TN on some extent, but has no influence in the leaching velocity of TP. PH influences the leaching rules of CODcr, BOD5, TP, NH₃-N and TN on some extent.Taking into account of the economic conditions, terrains, production characteristics and pollution properties of MSW in Songtao reservoir, the countermeasures for the prevention and cure of MSW in Songtao reservoir are advised.