翻车机卸料作业过程通风除尘系统研究
发布时间：2018-11-10 19:55
【摘要】：翻车机系统是一种非常专业化的散装物料卸料系统,它用于火车装载的散状物料的自动翻卸。随着这些企业规模的扩大及现代化程度的提高,受到越来越多工程行业的重视。但是,翻车机系统在翻卸散装物料的过程中,由于落差较大,翻车机体积庞大,煤排开的大量空气携带粉尘到处飞扬,造成翻车机室空气严重污染,影响工人健康。通风除尘是做好粉尘防治的基本措施之一。在扬尘空间设置局部集气罩,通过合理的气流组织控制有害物是工业通风的重要技术手段。所以研究集气罩罩口气流分布的规律对于有效捕集粉尘十分重要。了解罩口吸气口和吹气口的气流的运动规律是合理设计集气罩及通风系统的基本依据。本论文以C型单车翻车机的卸料过程为依据,建立了物理模型,并对研究对象的物理模型做了适应的假设和简化。针对料斗两种不同结构分别对翻车机卸料过程造成的扬尘使用ANSYS14.5软件进行数值模拟,其中湍流模型选择RNGk-e模型,两相流模型选择是欧拉-拉格朗日离散项模型,并用实验验证了模型选择的可靠性。通过分析受煤坑内的流场特性,确定料斗为对称结构更好,且料斗底部扬尘速度约为1.5~4.5m/s。根据翻车机卸料的间歇性特点对卸料过程分为两个过程进行数值模拟,主要模拟双侧吸式和吹吸式两种除尘方案。通过分析受煤坑和料斗内的流场特性随集气罩的布置位置和罩口风速变化,确定最佳位置和风速。综合比较两种方案对粉尘控制效果和所需风量,得知吹风罩在抽风罩分别安装在两侧且吹风罩在下面的结构最优,最佳的吹吸气风速为吹气气流风速为4m/s,吸气气流风速为5m/s。在该情况下,实现对粉尘完成控制时所需要的风量最小,且其系统较简单,初投资也小。依据相似原则对受煤坑进行1:16缩小,对单侧吸式、双侧吸式和吹吸式三种除尘方案进行试验,测定在相同的风量下逸出的粉尘浓度。试验结果显示吹气风速小于吸气风速时,吹风口气流可以将粉尘稀释并扩大了吸风口粉尘捕集范围。在所需风量相同时,双侧吸式和吹吸式的除尘方案比单侧吸式除尘效果好,双侧吸式和吹吸式两种除尘方案的粉尘浓度比较接近,试验结果与模拟结果相吻合。
[Abstract]:The dumper system is a specialized bulk material unloading system, which is used for automatic dump of bulk material loaded by train. With the expansion and modernization of these enterprises, more and more attention has been paid to the engineering industry. However, in the process of dumping and unloading bulk materials, because of the large drop, the volume of the dumper is huge, a large amount of air discharged by coal flies everywhere with dust, which results in serious air pollution in the dumper room and affects the health of the workers. Ventilation and dust removal is one of the basic measures for dust prevention. It is an important technical means of industrial ventilation to set up local gas collecting cover and control the harmful matter through reasonable airflow organization in the dust-raising space. Therefore, it is very important to study the law of air distribution at the hood mouth for effective dust capture. It is the basic basis for reasonable design of air collecting hood and ventilation system to understand the moving law of the air flow at the suction and blowing ports of the hood. Based on the unloading process of C type bicycle dumper, the physical model is established in this paper, and the adaptive assumption and simplification of the physical model of the research object are made. According to two different structures of hopper, ANSYS14.5 software is used to simulate the dust caused by the unloading process of the dumper. The RNGk-e model is chosen as the turbulence model, and the Euler-Lagrangian discrete term model is chosen as the two-phase flow model. The reliability of model selection is verified by experiments. By analyzing the flow field characteristics in the coal pit, it is found that the hopper is of symmetrical structure, and the dust velocity at the bottom of the hopper is about 1.5 ~ 4.5 m / s. According to the intermittent characteristics of unloading of dumper, the unloading process is divided into two kinds of numerical simulation, mainly simulating two kinds of dust removal schemes: double suction type and blowing suction type. By analyzing the variation of flow field characteristics in coal pits and hoppers with the arrangement of the collecting hood and the wind speed at the hood mouth, the optimum position and wind speed are determined. By comparing the effect of the two schemes on dust control and the required air volume, it is found that the air blowing cover is installed on both sides of the exhaust hood and the air blowing cover is below the optimal structure. The best inspiratory velocity is 4 m / s. The inspiratory wind speed is 5 m / s. In this case, the minimum amount of air is needed to complete the dust control, and the system is simple and the initial investment is small. According to the principle of similarity, the coal pit was reduced at 1:16, and the dust concentration was measured under the same air volume by testing the three schemes of single suction, double suction and blowing suction. The experimental results show that when the air velocity is less than the suction velocity, the dust can be diluted and the range of dust capture can be enlarged. When the required air volume is the same, the dust-removal schemes of bilateral suction and blow-suction are better than those of single-side suction. The dust concentration of the two schemes is close, and the experimental results are in good agreement with the simulation results.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD714.4
本文编号：2323451
[Abstract]:The dumper system is a specialized bulk material unloading system, which is used for automatic dump of bulk material loaded by train. With the expansion and modernization of these enterprises, more and more attention has been paid to the engineering industry. However, in the process of dumping and unloading bulk materials, because of the large drop, the volume of the dumper is huge, a large amount of air discharged by coal flies everywhere with dust, which results in serious air pollution in the dumper room and affects the health of the workers. Ventilation and dust removal is one of the basic measures for dust prevention. It is an important technical means of industrial ventilation to set up local gas collecting cover and control the harmful matter through reasonable airflow organization in the dust-raising space. Therefore, it is very important to study the law of air distribution at the hood mouth for effective dust capture. It is the basic basis for reasonable design of air collecting hood and ventilation system to understand the moving law of the air flow at the suction and blowing ports of the hood. Based on the unloading process of C type bicycle dumper, the physical model is established in this paper, and the adaptive assumption and simplification of the physical model of the research object are made. According to two different structures of hopper, ANSYS14.5 software is used to simulate the dust caused by the unloading process of the dumper. The RNGk-e model is chosen as the turbulence model, and the Euler-Lagrangian discrete term model is chosen as the two-phase flow model. The reliability of model selection is verified by experiments. By analyzing the flow field characteristics in the coal pit, it is found that the hopper is of symmetrical structure, and the dust velocity at the bottom of the hopper is about 1.5 ~ 4.5 m / s. According to the intermittent characteristics of unloading of dumper, the unloading process is divided into two kinds of numerical simulation, mainly simulating two kinds of dust removal schemes: double suction type and blowing suction type. By analyzing the variation of flow field characteristics in coal pits and hoppers with the arrangement of the collecting hood and the wind speed at the hood mouth, the optimum position and wind speed are determined. By comparing the effect of the two schemes on dust control and the required air volume, it is found that the air blowing cover is installed on both sides of the exhaust hood and the air blowing cover is below the optimal structure. The best inspiratory velocity is 4 m / s. The inspiratory wind speed is 5 m / s. In this case, the minimum amount of air is needed to complete the dust control, and the system is simple and the initial investment is small. According to the principle of similarity, the coal pit was reduced at 1:16, and the dust concentration was measured under the same air volume by testing the three schemes of single suction, double suction and blowing suction. The experimental results show that when the air velocity is less than the suction velocity, the dust can be diluted and the range of dust capture can be enlarged. When the required air volume is the same, the dust-removal schemes of bilateral suction and blow-suction are better than those of single-side suction. The dust concentration of the two schemes is close, and the experimental results are in good agreement with the simulation results.
【学位授予单位】：中国矿业大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TD714.4
【参考文献】
相关期刊论文 前3条
1 周威明,余澄海;粉尘控制新技术[J];工业安全与环保;2004年03期
2 薛群山;;侧倾式翻车机粉尘污染治理研究[J];河南电力;2002年03期
3 宋凤莲;;电厂输煤系统粉尘防治研究[J];中国电力;2010年03期
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