China Coal Technology and Engineering Group, Chongqing Research Institute, No. 55, Shangqiao Village 3, Shapingba District, Chongqing City, 400037, China.
Environ Sci Pollut Res Int. 2020 Jan;27(2):1721-1733. doi: 10.1007/s11356-019-06847-8. Epub 2019 Nov 21.
To solve the problem of dust production by the caving coal seam on the weather side of a fully mechanized coal face with a large mining height, this study proposes coal cutter onboard dust removal technology for the first time. In this work, taking the 12511 fully mechanized coal face of the Bulianta Coal Mine with a large mining height as an example, a mathematical model was built to study the influence of the onboard dust collector on airflow-dust dispersion pollution and the key technological parameters of the dust collector, and field tests were performed for verification. The results of numerical simulation showed that the dust-carrying airflow, after being blocked by the coal cutter, dispersed in the lateral direction, leading to an increase of airflow velocity on the walkway side to 1.75 m s, and a dust concentration as high as 2500 mg m. At the same time, an airflow vortex area with the largest diameter of 3 m was formed near the surface of the coal cutter body, which attracted dust to gather there. However, after the application of the onboard dust removal technology, the lateral dispersion of dust-carrying airflow weakened, and the dust concentration on the walkway side was reduced to below 600 mg m. In addition, this technology also obviously reduced the influence scope of the vortex and the dust concentration area. It was also found that the installation height of the suction inlet of the dust collector and the air capacity had a large impact on the dust suppression efficiency. The optimum dust suppression efficiency was reached at an installation height of 1.15 m and air capacity of 120 m min. Field test verification demonstrated that the dust concentration on the walkway side could be reduced by as much as 49.3% with the application of the proposed onboard dust removal technology.
为解决大采高综采工作面下风侧煤体片帮产尘问题，首次提出采煤机机载除尘技术。以布尔台矿 12511 大采高综采工作面为例，建立数学模型研究机载除尘器对风流-粉尘扩散污染的影响及除尘器关键技术参数，并进行现场试验验证。数值模拟结果表明，采煤机截割煤体后，含尘气流向两侧扩散，造成人行道侧风速增至 1.75 m/s，粉尘浓度高达 2500 mg/m。同时，在采煤机机身表面附近形成最大直径 3 m 的气流涡旋区，吸引粉尘在此聚集。然而，采用机载除尘技术后，含尘气流的侧向扩散减弱，人行道侧粉尘浓度降低至 600 mg/m 以下。此外，该技术还明显减小了涡旋和粉尘浓度区的影响范围。还发现，除尘器吸风口安装高度和空气量对抑尘效率有很大影响。在安装高度为 1.15 m 和空气量为 120 m/min 时，达到最佳抑尘效率。现场试验验证表明，采用所提出的机载除尘技术可使人行道侧粉尘浓度降低 49.3%。
