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With the development of the national economy and people's living standards improve, and the rapid increase of the urban population, a large number of industrial and domestic waste generated, the increasingly serious environmental pollution. Statistics show that China's urban per capita annual output of garbage 400kg major cities across the country with an annual output of garbage 1.5 × 10 8 t, city garbage storage capacity has reached 6.0 × 10 9 t, occupation of the land area of ??5 × 10 8 m 2 , and the annual growth rate of 8% 1 0% of the speed of growth. The flooded rubbish, forcing people to take positive measures to be scientific and rational treatment and utilization, reduction, recycling, harmless. Experiments show that the incineration of waste can be reduced by 90% the capacity of the garbage, the mass is reduced by 75%, and does not form secondary pollution, every 3 to 4t garbage is equivalent to a ton of coal, is a available resources. Therefore, the waste-to-energy waste reduction, recycling, harmless. The purpose of the main city of Chongqing, Nissan garbage 3000T, landfill, only pollute the environment, but also result in the waste of land resources. Of a waste incineration plant, a day to dispose of refuse 1500t, garbage daily power generation of about 350,000 degrees. Municipal solid waste incineration flue gas contains a variety of harmful substances, if not to be cleansed direct emissions will be serious secondary pollution to the environment. The emission of harmful substances SO 2 is particularly important, the focus of this study is how effective removal of SO2. On the basis of comparative dry, wet, semi-dry flue gas purification technology, the choice of investment is smaller, low energy consumption, high purification efficiency, purification products to the dry state of semi-dry flue gas purification. Provisions in accordance with the European standard, the desulfurization rate greater than 98%. This article create a 3-drying tower model, and using the FLUENT software in the spray drying tower of the respective flue gas purification apparatus, respectively, were studied on the reaction, spray velocity vector field and the gas trace. Studies have shown: Model 1 and Model 2 has undesirable places. These two models is currently a lot of exhaust gas purification spaces with the main structure. Based on the model 1, 2, be optimized to improve. This paper three models in the intake speed of 1m / s conditions, exhaust gas residence time in the tower of the quantitative comparison results show that the optimization model in the data can better achieve the purpose of purification and requirements. Optimization model, this paper to consider CO exhaust 2 and not consider CO 2 both cases, the intake speed of 1m / s, Ca / S ratio of the influence on the desulfurization rate was analyzed. The results show that not consider the CO 2 when optimum Ca / S ratio of 1.3, and when considering the CO 2 exists when, optimum Ca / S ratio of 1.6, according to the actual situation, it is clear that waste incineration the generated exhaust contains large amounts of CO 2 CO 2 when the Ca / S ratio so I do not consider the lack of reference. Meanwhile, the case of considering CO2, the type of the intake air speed and the type of the Ca / S ratio lower desulfurization rate was studied. The study shows that in the inlet gas velocity of 0.8m / s, the optimal Ca / S ratio of 1.5; at the intake speed of 1m / s, the optimal Ca / S ratio of 1.6; in the intake air velocity for 1.2m / s, the optimum Ca / S ratio of 1.8. Finally, we get 2 aqueous solution of the flow rate of the intake speed and Ca (OH) Mapping results indicate that the intake speed of the gas and the Ca (OH) 2 aqueous solution of the flow rate is proportional to the relationship. These data directly to the corporate officers of real-time operating to provide a quantitative basis and numerical reference.
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