乌达矿区煤自燃预测标志气体研究

为遴选预测煤自燃进程的标志气体,采集了乌达矿区6个具有代表性的煤样.在实验室开展煤升温氧化气体产物的测定实验,主要测试了煤样在升温氧化条件下各种气体组分的发生量.根据各种气体组分的发生量及最低检测温度,确定了乌达矿区煤自燃预测预报的标志气体,为该矿区煤自燃火灾的预测预报提供了实验依据,对矿区的安全生产具有较好的指导作用.     

煤升温氧化过程中气体解析规律研究

为了防止煤炭自燃,深入了解煤在升温氧化过程中气体的释放规律,利用煤升温氧化实验系统,对太原组和山西组煤进行了升温氧化实验.结果表明,太原组和山西组煤在升温氧化过程中,不同气体有不同的释放临界温度和速率,20～160℃为煤的缓慢氧化阶段,从煤中缓慢释放出被吸附的C1气体CO,CO2,CH4和C2～C3的烯烃C2H4,C3H6等;160～210℃为煤的快速氧化阶段,从煤中释放出较大量的C2～C4的烷烃C2H6,C3H8和C4H10等,烃的体积分数以指数速率增加;210～280℃为煤的急速氧化阶段,上述C1～C4气体的体积分数几乎以直线关系急剧增加.不同类型的煤在不同的氧化阶段具有不同的氧化特征,可选择不同的气体作为预测煤自燃特性的标志气体.     

乌达矿区煤自燃预测标志气体研究

为遴选预测煤自燃进程的标志气体,采集了乌达矿区6个具有代表性的煤样．在实验室开展煤升温氧化气体产物的测定实验,主要测试了煤样在升温氧化条件下各种气体组分的发生量．根据各种气体组分的发生量及最低检测温度,确定了乌达矿区煤自燃预测预报的标志气体,为该矿区煤自燃火灾的预测预报提供了实验依据,对矿区的安全生产具有较好的指导作用．     

粒径对煤氧化升温进程影响的试验研究

为研究粒径对煤氧化升温进程的影响,利用程序升温试验系统,分析潞安集团李阳煤矿15号煤层5种不同粒径煤样氧化升温进程中O_2,CO,C_2H_4等气体的生成规律,并计算了不同粒径煤样的耗氧速率和CO,CO_2,C_2H_4气体的产生速率以及煤自燃倾向性判定指数。结果表明:该煤层自燃临界温度约80℃,干裂温度约135℃,气体产生速率临界温度约160℃;从试验初期到干裂温度段,各煤样气体生成总量变化不大,超过干裂温度后,气体生成量变化幅度增大;煤样在超过气体产生速率临界温度后,各气体的产生速率开始有较大幅度增加,且粒径越小的煤样气体产生速率的变化幅度越大;随着煤样粒径的减小,煤样和O_2反应面积增大,交叉点温度相应降低,煤样粒径对煤自燃倾向性有明显影响。     

不同煤种自燃指标气体优化研究

为研究不同煤种的自燃指标气体变化规律,提高煤早期自燃预测预报的准确度,采用氧化升温试验系统,运用灰色关联分析方法,重点将5种煤样生成的自燃指标气体与温度的相关性进行分析。结果表明:随着温度升高,多数煤样在氧化升温过程中产生的CO,C_2H_4,C_2H_6气体体积分数呈曲线上升趋势;随着变质程度加深,煤在氧化升温过程中产生的自燃指标气体(CO,C_2H_4)体积分数随之降低,气体出现的温度点也随之升高,C_2H_6的情况则正好相反;变质程度最深的无烟煤最优自燃指标气体为CO,变质程度最浅的褐煤首选自燃指标气体为烷烯比,其余煤样的最优自燃指标气体为C_2H_6。研究结果将对矿井火灾预防起到指导作用。     

煤炭自燃的自由基反应机理

用自由基反应机理阐明了煤炭自燃机理，论述了煤中自由基产生的原因、自由基反应历程、煤氧化过程中逸出的气体成份。最后，用该机理对常见的几种煤炭自燃现象进行了解释。     

煤炭自燃特性研究的加速量热法

利用加速量热法研究煤炭自燃特性，所用煤样量少、实验时间短，可得到煤炭的初始自加热温度、煤炭升温曲线和耗氧曲线。进行了煤炭自燃过程的化学动力学研究，建立了煤氧化反应的活化能计算方法，得到了试验煤样在缓慢氧化阶段和激烈氧化阶段的活化能数据。     

煤自燃倾向性的氧化动力学测定方法研究

通过煤自燃过程中的绝热氧化升温速率、耗氧量、交叉点温度的综合分析研究,指出以煤自燃某一阶段的单一特征参数无法体现煤自燃过程的整体特性,提出了煤自燃倾向性的氧化动力学测定方法.该方法在测试程序升温条件下煤样温度70℃时煤样罐出气口氧气浓度和之后的交叉点温度的基础上,得出煤自燃倾向性的氧化动力学综合判定指数,根据该指数的大小判定煤自燃倾向性的强弱.对不同煤种的综合判定指数与绝热氧化、30℃物理吸氧量对比分析,结果表明氧化动力学综合判定指数更能够反映煤自燃的难易程度.     

注氮惰化窒息燃烧煤炭氧浓度的实验研究

利用煤炭自燃实验系统,对龙固煤矿7煤煤样的自燃过程进行了模拟实验.实验研究了注氮情况下的煤氧化煤温、自燃状态与氧含量的变化关系,确定了龙固煤矿7煤煤样窒息的最低氧浓度,研究结果对使用注氮防治煤炭自燃技术的应用具有重要的现实指导意义.     

煤自然发火烯烃指标及其煤岩学因素分析

本文探讨了煤氧化过程中烯烃气体产出特征，分析了烯烃气体产出速率的煤岩学因素，认为煤阶（变质程度）、煤岩成分及还原性等煤岩特征对烯烃气体产出特征有很大影响，乙烯是预测煤炭自燃的较好指标。     

积水区下煤层的安全回采

介绍了积水区探放水设计的主要内容,讨论了下煤层开采的基本方法,提出了几点重要的安全措施.     

Effects of coal seam dip angle on the outburst in coal roadway excavation

The prevention and forecast of coal and gas outburst has always been one of the key issues in coal mining safety. By simulating the process of tunneling in coal seam with different dip angle through FLAC3D software, the dangerous zone in which outburst may occur and the probability of outburst near the working face were predicted through the distribution of stress, displacement and plastic zone. Then we discussed the size of unstable area in the surrounding rock through the distribution of stress and the variation curve of the displacement on the roadway wall. The results show that, with an increase of the coal seam dip angle, the risk of outburst in the working face rises gradually. And the dangerous areas in which may outburst occur moves to the upper part of coal seam. The size of unstable area in the surrounding rock increases with the increase of coal seam dip angle.     

Top coal caving mining technique in thick coal seam beneath the earth dam

It is important to study the mining technology under structures for raising the coal resources recovery ratio. Based on the geological and mining conditions, the top coal caving harmonic mining technique in thick coal seam beneath the earth dam was put forward and studied. The 5 factors such as the panel mining direction, panel size, panel location, panel mining sequence and panel advance velocity were taken into account in this technique. The dam movement and deformation were predicted after the thick coal seam mining and the effects of mining on the dam were studied. By setting up the surveying stations on the dam, the movement and deformation of the dam were observed during mining. By taking some protective measures on the dam, the top coal caving mining technique in thick coal seam beneath the earth dam was carried out successfully. The study demonstrates that harmonic mining in thick coal seam is feasible under the dam. The safety of the earth dam after mining was ensured and the coal resources recovery ratio was improved.     

巨厚煤层冲击地压的防治研究

通过对义煤集团千秋煤矿有冲击倾向巨厚煤层冲击现象现状、特点及影响因素分析,结合该矿的生产实践,提出了适合该条件的冲击危险预测方法及相应解危措施,并进一步提出解危措施效果检验方法以及以上工作失败、冲击地压突发情况下的应急措施;在此基础上建立了适合义煤千秋矿巨厚煤层冲击地压防治的安全开采体系,成功地进行了巨厚煤层的综放开采,从而为有冲击倾向巨厚煤层的安全开采提供了成功范例.     

焦作九里山矿单体支柱放顶煤工作面顶煤运动放出规律浅析

通过焦作矿务局九里山矿单体支柱放顶煤工作面现场实测,得出单体支柱放顶煤工作面顶煤运动、破碎、放煤过程中煤流动态及放出椭球体规律,为确定合理放顶煤工艺参数提供了可靠的依据.合理的放煤工艺参数不但提高了回收率,而且保证了工作面正常生产,这对焦作矿区今后采煤方法的改革具有重要的指导意义.     

新安煤田正村井田二叠系煤岩层对比

煤岩层对比工作对于煤田地质勘探、储量计算以及煤炭资源的开发利用都具有极其重要的意义,它是研究含煤地层层序、煤田地质构造、煤层厚度变化、煤层赋存规律的基础工作,是煤田地质勘探工作的主要任务之一.本文采用标志层法、层间距法、煤质特征分析法和测井响应,对本区的主要含煤层段二叠系山西组、上下石盒子组进行了系统的划分和对比,准确确定了主要可采煤层二1煤层和局部可采煤层二2煤层、七2煤层的层位,并对这些煤层的空间展布进行了对比,这一煤岩层对比方案已为煤田勘探和煤矿开采的揭露所证实.     

Application of coal mine roof rating in Chinese coal mines

The coal mine roof rating(CMRR) is a measure of roof quality or structure competency for bedded roof types typically of underground coal mines. The CMRR has been used widely in the US, South Africa,Canada and Australia. In order to investigate the application of the CMRR system in Chinese coal mines,two coal mines in China located in Panjiang Coal Field in Guizhou Province were investigated. Field data were collected which is required to calculate the CMRR value based on underground exposure. The CMRR values of 11 locations in two coal mines were calculated. The investigations demonstrated that the chance of mine roof failure is very low if the CMRR value is more than 50, given adequate support is installed in mine. It was found that the CMRR guideline are useful to preliminarily investigate stability in Panjiang Coal Field mines.     

Arch structure effect of the coal gangue flow of the fully mechanized caving in special thick coal seam and its impact on the loss of top coal

Based on the characteristics of the top coal thickness of the fully mechanized caving in special thick coal seam,the long distance of coal gangue caving,as well as the different sizes of the coal gangue broken fragment dimension and spatial variation of drop flow,this paper uses laboratory dispersion simulation experiment and theoretical analysis to study the arch structure effect and its influence rule on the top coal loss in the process of coal gangue flow.Research shows that in the process of coal gangue flow,arch structure can be formed in three types:the lower arch structure,middle arch structure,and upper arch structure.Moreover,the arch structure has the characteristics of dynamic random arch,the formation probability of dynamic random arch with different layers is not the same,dynamic random arch caused the reduction of the top coal fluency;analyzing the dynamic random arch formation mechanism,influencing factors,and the conditions of instability;the formation probability of the lower arch structure is the highest,the whole coal arch and the coal gangue arch structure has the greatest impact on top coal loss.Therefore,to prevent or reduce the formation of lower whole coal arch structure,the lower coal gangue arch structure and the middle whole coal arch structure is the key to reduce the top coal loss.The research conclusion provides theoretical basis for the further improvement of the top coal recovery rate of the fully mechanized caving in extra thick coal seam.