| With the development of urbanization, in order to realize the municipal solid wastes’(MSW) clean-treatment which has become the hot topic in society, and seek a method under the purpose of achieving “Reduce, Recycle, Reuse” of waste disposal, cement kiln co-processing MSW system is proposed thereby. In this paper, taking Luoyang Huanghe Tongli cement Co., LTD a 200t/d MSW incineration as an example, the use of cement industry number of heat flux and high temperature exhaust gas was pumped into waste incinerator, with Aspen Plus software simulating and calculating waste incineration process and cement production process, to provide theoretical support and reference data for cement kiln co-processing system, and by optimizing the model structure, a new optimization system was put forward. Its main idea is as follows:(1) The analysis of the process of the system and the determining of the parameters of the MSW incineration. Firstly, the system process was discussed in this paper, and the cement industry of preheater, decomposition kiln, rotary kiln equipment such as the structure and working principle are analyzed. Secondly, on the basis of the characteristics of MSW, rotary waste incinerator for waste incineration equipment was selected, and thermodynamic analysis was carried out on it, indicating that MSW was combusted by the tertiary air from kiln head without adding other fossil fuel. At the same time according to thermodynamic analysis, the size and the operation parameters of the incinerator were determined.(2) The simulation analysis of the system. Based on Aspen Plus, through to the coal/waste incineration, raw matieral decomposition, suspended preheating modeling and analysis, the basic principle of each process in the system was determined. And depending on the system, the system is divided into waste incinerator, decomposition kiln, rotary kiln and preheater four parts. For waste incinerator, When tertiary air mass flow was ranged from 404kg/min to 475 kg/min, the temperature of flue gas outlet was 922℃~1162℃, restraining pollution gases. And analyzing flue gas of CO, CO2, NOX, SOX, etc, the vary of tertiary air was determined to adapt to the system. Compared with the decomposition kiln in the common, the temperature would also be reached in the decomposition kiln with MSW incineration system, with the result tertiary air increasing 25%, coal saving 4.4%. When the incinerator was consumming air accounts for 12% ~ 19% of total mass flow wind, the working temperature of decomposition kiln was the best. From the study of the cement rotary kiln and preheater, it is showed that they had no influence on system. The results of the integrated system and the segmentation system were in the range of allowable error.(3) Based on Aspen Plus, optimize the entire system and put forward improvement scheme. Firstly, for waste incinerator, the temperature of incinerator was increased by 29.9%, the consumption of tertiary air was reduced by 21%, with the use of the exhaust gas of preheater or the heat flux of waste ash. Secondly, for decomposition kiln, the core of the system, the utilization rate of tertiary air and the pulverized coal combustion were improved, along with getting a higher gas temperature and reducing the emission of NOX, when tertiary air or pulverized coal was supplied segmentaly. |
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