矿井瓦斯防治基础知识基础知识（Basic knowledge of mine gas control）.docVIP

矿井瓦斯防治基础知识基础知识（Basic knowledge of mine gas control） Two. Basic knowledge 1. basic knowledge of mine gas control (1) gas generation and zonation in coalfield The gas in the coal seam is the associated product of the coal debris during the formation of coal. The process of coal formation can be divided into two stages: The first stage is the diagenetic stage of induration. The accumulation of organic matter in peat and decomposed into lignite, coal forming early enough oxygen to promote organic biological reaction, the decomposition of methane, carbon dioxide, nitrogen oxides and sulfur amount of. With the change of conditions, the decrease of oxygen supply and the change of microbial environment begin to lead to anaerobic process, and further release methane, heavy hydrocarbon, hydrogen sulfide, ammonia gas, hydrogen gas and other gases. Right now,. The vast majority of methane is emitted in the atmosphere. The second stage is metamorphic carbonization stage. With the upper coal seam buried depth, thick alluvium continuously deepening, in the role of formation temperature and pressure, peat, lignite continuously transformation in coal seam reduce volatile, fixed carbon increased, as bituminous coal, anthracite, at this time, stop gas microbial activities are no longer produced biological sources. Most of the generated gas flows into the atmosphere, with only a few remaining in rocks and coal seams. Due to geological reasons, carbon dioxide, nitrogen and rare gas from the coal seam exposed to the surface (outcrop) air will also seep into the coal seam. In addition to this but the radioactive material in the coal seam will be decomposed into helium generation in coal seam depends the helium content of coal, more old, helium content is higher, but the coal adsorption of helium, in the free state, most of the helium to the ground. In addition, carbonate rocks, which are affected by volcanic activity, also decompose large amounts of carbon dioxide. According to the coal s