热逆流氧化装置流量分配特性研究

发布时间：2018-06-24 03:53

本文选题：乏风瓦斯 + 热氧化　；参考：《山东理工大学》2014年硕士论文

【摘要】：由于煤矿通风瓦斯是很难使用，一般直接排空，这不仅浪费能源，，而且还污染空气，增加温室效应。所以，利用热逆流氧化装置来减少乏风瓦斯，同时对促进节能减排和低碳经济的发展具有重大意义。因此，深入研究热逆流氧化装置氧化床的热态阻力特性，掌握各参数对其阻力特性的影响规律以及流量分配与热阻力的影响关系，来提高氧化床温度分布的均匀性，这将对热逆流氧化装置的性能优化和运行可靠性有重要意义。首先，进行了乏风瓦斯热氧化数值计算模型的建立和实验验证。以S.Zhdanok等人的实验为原型，利用fluent软件，采用多孔介质模型对实验进行了数值计算，通过对比模拟值和实验值来验证模拟方法的准确性。其次，本文针对山东理工大学自主研发的处理量为60000m3/h的煤矿乏风热逆流氧化装置，创建氧化床的三维物理模型以及热氧化的控制方程，选用多孔介质模型,当量连续法研究了一个工作循环内单向流动时各参数，包括进气参数（包括进气表观速度，进气甲烷浓度）；几何参数（包括孔隙率，氧化床高度）；物性参数（包括陶瓷的密度，比热，导热系数）；运行参数（包括散热功率，初始温度场）对氧化床流动方向中间横截面上的温度分布和压差变化的影响，以及蜂窝陶瓷氧化床一个工作循环内的阻力非定常变化特性。结果表明：燃烧波的移动速度与进气速度、气体的温度和压力有关；阻力损失与高温区面积有关；阻力损失的非定常变化与放热量和散热量的相对大小有关。最后，本文针对山东理工大学自主研发的处理量为60000m3/h的煤矿乏风热逆流氧化装置，建立二维物理模型，选用多孔介质模型,当量连续法进行模拟研究了热逆流氧化装置氧化床的二维流量分配和温度分布非定常波动特性。主要研究了进气参数，几何参数，物性参数，运行参数对氧化床内比流量分布不均匀性和温度分布不均匀性的影响规律。得出流量分配与热阻力分布的影响关系来提高氧化床比流量分布和温度分布的均匀性，从而，提高氧化床寿命和运行安全性。
[Abstract]:Because coal mine ventilation gas is very difficult to use, it is usually directly emptied, which not only wastes energy, but also pollutes air and increases Greenhouse Effect. Therefore, it is of great significance to use the heat countercurrent oxidation device to reduce the exhaust gas and to promote the development of energy saving and low carbon economy. In order to improve the uniformity of oxidation bed temperature distribution, the thermal resistance characteristics of oxidation bed in hot countercurrent oxidation unit are studied in depth, and the influence law of various parameters on the resistance characteristics and the relationship between flow distribution and thermal resistance are grasped in order to improve the uniformity of oxidation bed temperature distribution. This will be of great significance to the performance optimization and operation reliability of the thermal countercurrent oxidation device. First of all, the numerical model and experimental verification of the thermal oxidation of exhaust gas are carried out. Taking S. Zhdanok et al.'s experiment as the prototype and using fluent software, the numerical calculation of the experiment is carried out by using the porous media model. The accuracy of the simulation method is verified by comparing the simulated values with the experimental values. Secondly, in this paper, the three-dimensional physical model of oxidation bed and the governing equation of thermal oxidation are established for the coal mine waste heat countercurrent oxidation unit, which has been developed independently by Shandong University of Technology, and the porous medium model is selected. The equivalent continuum method has been used to study the parameters of unidirectional flow in a working cycle, including inlet air parameters (including apparent inlet velocity, inlet methane concentration), geometric parameters (including porosity, oxidation bed height), and so on. The effects of physical parameters (including ceramic density, specific heat, thermal conductivity) and operating parameters (including heat dissipation power, initial temperature field) on the temperature distribution and pressure difference in the intermediate cross section of the flow direction of the oxidized bed, And the unsteady variation of resistance in a working cycle of honeycomb ceramic oxidation bed. The results show that the moving velocity of the combustion wave is related to the inlet velocity, the temperature and pressure of the gas, the resistance loss is related to the area of the high temperature region, and the unsteady variation of the resistance loss is related to the relative magnitude of the heat release and heat dissipation. Finally, a two-dimensional physical model and a porous medium model are established for the counter-current oxidation device of coal mine with the capacity of 60000m3/h, which is developed by Shandong University of Science and Technology. The two-dimensional flow distribution and unsteady fluctuation of temperature distribution in oxidation bed of hot countercurrent oxidation unit were simulated by equivalent continuous method. The effects of air intake parameters, geometric parameters, physical parameters and operation parameters on the non-uniformity of specific flow distribution and temperature distribution in the oxidation bed are studied. The relationship between flow distribution and thermal resistance distribution is obtained to improve the uniformity of specific flow distribution and temperature distribution of oxidized bed, so as to improve the life and safety of oxidation bed.
【学位授予单位】：山东理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TD712

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