为降低乏风瓦斯排放对温室效应的影响,提高乏风瓦斯的利用率,探究了体积分数为0.75%的乏风瓦斯及其与褐煤、无烟煤混烧方法下的氧化规律。随后进一步探究矿井乏风中裹挟的钙质泥岩粉尘对混烧体系中乏风瓦斯的影响。研究利用管式炉系统,模拟乏风瓦斯与空气预混气体环境,将金属氧化物含量不同的钙质泥岩粉尘与不同煤种混合,置于该气体环境中。结合X射线衍射分析(XRD)测试,分析混烧产物。研究表明:钙质泥岩粉尘可以促进瓦斯的氧化,且随着金属氧化物含量的增多,氧化效率增加。钙质泥岩粉尘可以促进同等温度下两个煤种混烧体系中乏风瓦斯的氧化。钙质泥岩粉尘金属氧化物含量越多,乏风瓦斯转化达到极限的温度越低。根据粉尘对两个煤种混烧体系的瓦斯转化作用效果可知,虽然褐煤体系的瓦斯转化率一直高于无烟煤体系,但粉尘对于褐煤体系中乏风瓦斯的转化呈负面影响,对无烟煤体系呈积极影响,故粉尘对无烟煤混烧体系的影响优于对褐煤体系的影响。钙质泥岩粉尘同时起到固硫作用,故对矿井排出乏风瓦斯过程中含有的钙质泥岩粉尘可不做处理,将其与乏风瓦斯共同通入燃煤锅炉中。

In order to reduce the impact of ventilation air methane (VAM) emission on thegreenhouse effect, we investigated the oxidation pattern of VAM with a concentration of 0.75%and its mixing method with lignite and anthracite, and the effect of the calcareous mudstone dustin VAM on the VAM in mixed firing system. Calcareous mudstone dust with different metal oxidecontent was mixed with different coal species and placed in this gas environment by using atube furnace system to simulate a premixed gas environment of VAM and air. X-ray diffraction(XRD) analysis was used to analyze, the mixed firing products. The study shows that: calcareousmudstone dust can promote the oxidation of gas, and the oxidation efficiency increases withthe increase of metal oxide content. Calcareous mudstone dust can promote the oxidation of VAM in the mixed firing system at the same temperature, and the higher the metal oxide content ofcalcareous mudstone dust, the lower the temperature at which the conversion of spent air gas reachesits limit. According to the effect of dust on the gas conversion of the two coal blending systems,it can be seen that although the gas conversion rate of the lignite system is always higherthan that of the anthracite system, the dust has a negative effect on the conversion of the VAM inthe lignite system and a positive effect on the anthracite system, so the effect of dust on the anthraciteblending system is better than that on the lignite system. Calcareous mudstone dust alsoplays the role of sulfur fixation, so the calcareous mudstone dust involved in the process of dischargingVAM from the mine can be left untreated and passed into the coal-fired boiler togetherwith VAM.