高瓦斯矿井选煤厂煤仓瓦斯规律模拟研究

发布时间：2018-06-13 19:10

本文选题：选煤厂 + 煤仓　；参考：《太原理工大学》2013年硕士论文

【摘要】：瓦斯吸附在煤中,要经过很长时间才能全部解吸,因此采出的煤炭即便进入选煤厂仍有部分瓦斯遗留在煤中,并随着时间的推移逐步从煤中溢出,选煤厂的储煤仓留有煤炭较多、留存时间较长、环境相对封闭,容易造成瓦斯积聚甚至引起瓦斯爆炸,给选煤厂的安全生产造成严重的威胁本文应用多孔介质的流体动力学理论原理,结合选煤厂煤仓的结构特点以及煤粒吸附特性,对煤仓内部空气流动矢量场和瓦斯浓度分布情况进行了数值模拟研究,根据模拟结果,结合虎龙沟矿选煤厂储煤仓的实际,给出了有效控制了煤仓瓦斯浓度的方法。根据多孔介质的流体动力学原理,具体考虑储煤仓内部瓦斯流动特性,应用控制流体运动的动量、质量、组分守恒定律,建立自然通风条件下和采用强制通风措施条件下的瓦斯流动通用数学描述模型；基于煤仓内部贮煤存在形式与采空区遗煤存在形式相似,因此在其内部的流体流动都属于多孔介质内的渗流和扩散,根据前人研究成果通过建立储煤仓内部瓦斯流动的控制微分方程,结合标准k—ε模型和SIMPLE算法求解离散化后的流体运动控制微分方程组；借助模拟软件F1uent对无通风措施、自然通风以及强制通风的条件下的储煤仓内部瓦斯流动进行模拟,得出储煤仓内部不同通风条件下的瓦斯浓度分布；根据模拟结果呈现的煤仓瓦斯分布呈由下及上不同浓度的分层规律,结合虎龙沟矿选煤厂储煤仓的现场实测情况,对虎龙沟矿选煤厂储煤仓进行通风改造。通过对比计算机模拟结果和现场实测情况可以得出,在不采取任何通风措施的情况下,煤仓内部瓦斯严重超标；通过采用建立通风孔和加装局部通风机的强制通风措施,模拟了煤仓瓦斯浓度分布,结合虎龙沟矿选煤厂储煤仓的现场监控数据确定了局部通风机的合理功率和风量,并针对虎龙沟矿选煤厂储煤仓实际情况,给出有效控制煤仓瓦斯浓度的方法。验证了运用模拟结果提出的通风孔和加装局部通风机的办法防治煤仓瓦斯积聚,可以有效解决煤仓瓦斯超限问题。
[Abstract]:It takes a long time for the gas to be adsorbed in the coal before it can be completely desorbed, so even if the extracted coal enters the coal preparation plant, part of the gas remains in the coal and gradually spills out from the coal over time. The coal storage bunker in the coal preparation plant has more coal, longer retention time and relatively closed environment, which can easily cause gas accumulation and even cause gas explosion. This paper applies the theory of fluid dynamics of porous media, combined with the structural characteristics of coal bunker and the adsorption characteristics of coal particles in coal preparation plant. The air flow vector field and gas concentration distribution in coal bunker are numerically simulated. According to the simulation results and the actual situation of coal storage bunker in coal preparation plant of Hulonggou Mine, the method of effectively controlling the gas concentration in coal bunker is given. According to the hydrodynamic principle of porous media, considering the gas flow characteristics in coal storage bunker, the law of conservation of momentum, mass and component is applied to control the movement of fluid. A general mathematical description model of gas flow under natural ventilation and forced ventilation is established, based on the fact that the existing form of coal storage in the coal bunker is similar to that of the remaining coal in the goaf. Therefore, the fluid flow in its interior belongs to the seepage and diffusion in porous media. According to the previous research results, the governing differential equation of gas flow in coal storage bunker is established. Combining standard k- 蔚 model and simple algorithm to solve the discrete fluid motion control differential equation group, the simulation software F1uent is used to simulate the gas flow in the coal storage bin under the condition of no ventilation measures, natural ventilation and forced ventilation. The distribution of gas concentration under different ventilation conditions in coal storage bunker is obtained. According to the simulation results, the gas distribution in coal bunker is stratified from lower to upper different concentrations, combined with the field measurement of coal storage bunker in Hulonggou Coal preparation Plant. Ventilation transformation of coal storage bunker in coal preparation plant of Hulonggou Coal Mine was carried out. By comparing the results of computer simulation and field measurements, it can be concluded that, without any ventilation measures, the gas inside the coal bunker seriously exceeds the standard, and the forced ventilation measures of establishing ventilation holes and installing local ventilators are adopted. The distribution of gas concentration in coal bunker is simulated, and the reasonable power and air volume of local fan are determined by combining the field monitoring data of coal storage bunker in Hulonggou Coal preparation Plant, and aiming at the actual situation of coal storage bunker in Hulonggou Coal preparation Plant, The method of effectively controlling the gas concentration in coal bunker is given. It is verified that the method of preventing and controlling gas accumulation in coal bunker by means of ventilation hole and local fan, which is put forward by simulation results, can effectively solve the problem of gas exceeding limit in coal bunker.
【学位授予单位】：太原理工大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：TD712

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