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91.
在分析白额地区2#煤储层空间发育特征、储层物性特征、含气量分布特征及区域构造背景的基础上,对煤层气成藏控制因素进行分析。结果表明:构造演化史直接控制着煤储层埋藏史及生烃史,是煤层气成藏主控因素;地下水水动力特征和围岩封闭特征决定了煤层气藏的保存条件,是煤层气成藏的关键;综合以上特征,可以得出2#煤煤层气藏为单斜-水动力封堵型煤层气藏。 相似文献
92.
Biogenic coalbed gas,how it is generated and the geochemical characteristics of the gas are gaining global attention.The ways coalbed gas is generated,the status of research on the generation mechanism and the methods of differentiating between biogenic gasses are discussed.The generation of biogenic coalbed methane is consistent with anaerobic fermentation theory.Commercial biogenic coalbed gas reservoirs are mainly generated by the process of CO2 reduction.The substrates used by the microbes living in the coal include organic compounds,CO2,H2 and acetate.The production ratio and quantity of biogenic coalbed methane depend on the exposed surface area,the solubility and permeability of the coal and the microbial concentration in the coal seam.It is generally believed that biogenic coalbed gas has a value for σ13C1<-5.5%,C1/C1+>0.95.The H isotope ratio is controlled by both the environment and the generation mechanism:typically σD1<-20%.Biogenic methane formed by CO2 reduction has more σD1 than that formed by acetate fermentation. 相似文献
93.
Based on engineering tests in the Huainan coal mining area,we studied alternative well location to improve the performance of surface wells for remote pressure relief of coalbed methane in mining areas.The key factors,affecting location and well gas production were analyzed by simulation tests for similar material.The exploitation results indicate that wells located in various positions on panels could achieve relatively better gas production in regions with thin Cenozoic layers,low mining heights and slow rate of longwall advancement,but their periods of gas production lasted less than 230 days,as opposed to wells in regions with thick Cenozoic layers,greater mining heights and fast rates of Iongwall advancement.Wells near panel margins achieved relatively better gas production and lasted longer than centerline wells.The rules of development of mining fractures in strata over panels control gas production of surface wells.Mining fractures located in areas determined by lines of compaction and the effect of mining are well developed and can be maintained for long periods of time.Placing the well at the end of panels and on the updip return airway side of panels,determined by lines of compaction and the effect of mining,would result in surface wells for remote pressure relief CBM obtaining their longest gas production periods and highest cumulative gas production. 相似文献
94.
Based on controls of structural style and the position in coalbed methane(CBM)development,we used a method of curvatures to study its relations with CBM development parameters.We calculated structural curvatures of contours of the No.3coal seam floor of the Shanxi Formation in the Zaoyuan block of the Qinshui Basin and analyzed its relations with development parameters of coalbed methane wells.The results show that structural curvature is negatively related to coal reservoir pressure,while positively related to permeability.With an increase in structural curvature,the average production of coalbed methane wells increases at first and then decreases,reaching the highest production at 0.02 m-1 of structural curvature.Therefore,structural curvature can be an important index for potential evaluation of coalbed methane development and provide a basis for siting coalbed methane wells. 相似文献
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96.
采用非预混燃烧模型与组分传输的一步反应模型,模拟了甲烷燃烧及NOx的生成,得出燃烧温度场、NO生成情况。模拟结果表明:采用非预混燃烧模型模拟时结果更接近实测值,模拟更准确;甲烷扩散燃烧时NO产生区域主要集中在高温火焰后侧,在前部低温区基本没有NO生成;燃烧中P-NO生成量比T-NO量小两个数量级,NO产生几乎完全被热力型NO机制支配,在燃烧过程中应特别注意高温区域的影响。 相似文献
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Methane absorption and application of mixed organic aggregate prepared from Span80 and alkaline salt
The water-based materials for mine gas absorption and explosion suppression were prepared, in which the mixed organic aggregate
of Span80 and alkaline salt can be used as methane absorbent. Methane was used as a model of mine gas, and the absorptions
of methane with different complex materials were studied using head space gas chromatography. Then the state of aqueous material
was characterized with laser light scattering instrument and the effects of different complex materials on explosion suppression
were preliminarily studied in explosion chamber which can simulate mine gas explosion. The research results showed that complex
material could absorb methane and there was some correlation between the mean diameter of organic aggregate in aqueous material
and the absorption effect. Additionally, the aqueous material could suppress the methane explosion to some degree. The material
can absorb mine gas in atomization condition, therefore, degrease mine gas concentration and influence the distribution of
mine gas in the space, and then suppress the mine gas explosion to some extent. 相似文献
100.
以二甲基氨基甲叉二膦酸(DMMP)为原料,双氧水为氧化剂合成二甲基氨基甲叉二膦酸氮氧化物(DMMPO)。研究了原料配比、温度、时间及合成时pH值等条件对目标产物阻磷酸钙垢效果的影响,结果表明:n(DMMP)∶n(H2O2)=1∶3、反应温度为75℃、反应时间为2.5 h,并控制pH值为9左右时合成的DMMPO静态阻垢效果最好。通过IR和31P-NMR对产物进行了结构鉴定,同时对产品进行了活性物含量、亚磷酸根和磷酸根含量的测定,直接合成产物中活性组分含量为22.7%,亚磷酸根和磷酸根含量均小于0.1%。 相似文献