瓦斯抽采浓度控制机理及管路浓度自动调控预警系统研究

发布时间：2018-03-17 00:10

本文选题：瓦斯抽采　切入点：浓度控制　出处：《河南理工大学》2014年博士论文　论文类型：学位论文

【摘要】：煤层瓦斯抽采是治理矿井瓦斯和防治煤与瓦斯突出最有效方法之一,它不仅是安全生产的需要,也是节省能源、保护环境的迫切需要。而抽采钻孔和管路中的瓦斯浓度不仅关乎矿井安全,而且是抽采出来的瓦斯能否被利用的先决条件,如何提高管路瓦斯的抽采浓度,控制管路抽采瓦斯在爆炸限以外,是井下瓦斯抽采技术领域公认难题,实现管路瓦斯的检测监控以及瓦斯浓度的自动化调控对瓦斯抽采领域有着重要的意义。某时刻抽采瓦斯浓度的高低取决于钻孔内的瓦斯流量和漏气量的大小,围绕这一基本问题,文章对影响钻孔瓦斯流量的主控因素、影响钻孔漏气量的影响因素进行分析,为研究管路瓦斯抽采浓度自动化调控系统提供理论基础,论文的研究成果如下:1)在分析煤层瓦斯赋存与流动理论的基础上,利用达西定律,推导出了钻孔瓦斯流量的求解方程,并对影响其大小的因素进行理论分析,认为在同等条件下,不同煤层瓦斯压力下,如果负压的变化范围值相同,流量的改变量为一固定值;提出钻孔流量变化率以及单位负压流量变化率的概念,通过简化理论公式和赋值分析,提出通过计算单位负压流量变化率的大小合理优化其抽采负压的大小对提高钻孔瓦斯流量以及钻孔瓦斯浓度具有一定的实践意义。2)在对钻孔周围煤岩体应变和位移分析的基础上,基于钻孔漏气圈的概念,认为同等条件下,漏气圈面积越大,漏气量就越大,并对影响钻孔漏气圈面积大小的因素进行理论分析,通过探讨钻孔周围煤体渗透率的变化,应用气体渗流理论推导出了钻孔漏气量和钻孔瓦斯浓度的求解方程,结合前一章内容推导出计算某时刻钻孔瓦斯浓度的理论公式。3)提出基础浓度、汇入浓度和即时浓度的概念,认为调整即时浓度的大小的关键是改变钻孔的汇入浓度,并对其影响因素进行分析。其中主要是钻孔直径、塑性圈半径、封孔支护力、封孔段的有效长度、抽采过程中的负压。4)提出了流量加速度的观点,指出钻孔内瓦斯浓度随负压变化升高或降低,主要取决于瓦斯涌出量加速度和钻孔漏气量加速度的比值W,当W1时,提高负压可以提高封孔单元的瓦斯抽采浓度,降低抽采负压时将降低封孔单元的瓦斯抽采浓度;W1时,提高抽采负压时将降低封孔单元的瓦斯浓度,降低抽采负压时将提高封孔单元的瓦斯抽采浓度,在此基础上提出了利用W来合理优化瓦斯浓度的方法和建议。5)基于主动支护式封孔原理,研制了囊袋式注浆封孔装置,并进行了工程应用,实验证明了新型封孔方法与现行的聚氨酯封孔法相比可以提高钻孔的瓦斯浓度和抽采流量。6)设计出了煤层参数不同时瓦斯浓度随抽采负压变化的测试实验装置,并进行了不同煤层瓦斯压力下钻孔瓦斯浓度随抽采负压变化的实验分析,以及漏气量随抽采负压变化的实验分析,认为钻孔瓦斯的抽采浓度随抽采负压提高的变化趋势主要取决于煤层瓦斯压力、钻孔的密封程度以及漏气裂隙中微小颗粒的运动状态,并据此提出了最佳抽采负压的观点,认为在瓦斯抽采的过程中,抽采负压不是越高越好,也不是越低越好,而是存在一个最佳抽采负压,并进行了最佳抽采负压的归类分析,认为通过探寻最佳负压可以调整钻孔瓦斯抽采浓度,在保证最高抽采浓度的同时尽可能的降低漏气量。7)结合论文的理论分析以及实验室实验,提出了瓦斯抽采管路浓度自动调控预警系统的构想,系统利用计算机、传感器以及动作执行机构可检测并调整管路的抽采负压到最佳状态。并根据动作执行机构的不同设计了三套方案,经过比较,最终确定了以电动阀作为动作执行机构的方案。分别对主控系统、传感器、以及动作执行机构进行了讨论,完成了硬件设备的选型、PLC程序的设计、触摸屏组态界面设计上位机组态界面设计,并进行了全面的联机测试。8)在焦煤集团九里山矿进行了瓦斯浓度自动调控预警系统的安装测试,并根据工程实践地点的煤层地质条件和钻孔封孔参数进行了系统预设值的确定,搜索出了实验巷道的最佳抽采负压和最佳抽采浓度,证明了理论分析的正确性和系统的可靠性、实用性。
[Abstract]:Coal seam gas drainage is the governance of mine gas prevention and control of coal and gas outburst is one of the most effective methods, it is not only the need of safe production, but also saves energy, the urgent need to protect the environment. While the concentration of gas drainage drilling and pipeline is not only related to mine safety, but also is a prerequisite for gas drainage can be out how to improve the utilization of the pipeline gas drainage concentration control in gas explosion limit outside pumping pipeline, underground gas drainage technology difficult problem, the realization of pipeline gas detection and monitoring of gas concentration automatic control plays an important role in gas field. The gas flow and air leakage of a pumping time the gas concentration depends on the size of the hole, around the basic problem, the main influence factors of drilling gas flow, influence factors of air leakage of drilling Analysis of pipeline gas drainage concentration automatic control system to provide a theoretical basis, the research results of the thesis are as follows: 1) based on the analysis of the coal seam gas occurrence and flow theory, based on Darcy's law, the solution derived from the equation of gas flow of borehole, and the factors influencing the size of the theoretical analysis, think in the same under the condition of different gas pressure, if the change is negative of the same value, change the amount for a fixed value; the borehole flow change rate and the changes in the concept of negative pressure unit flow rate, by simplifying the theoretical formula and assignment analysis, put forward by calculating the unit negative pressure flow change rate of reasonable size optimization of the vacuum extraction the size of.2 has practical significance for improving the gas flow of borehole drilling and gas concentration) based on coal and rock around the borehole strain and displacement analysis, based on the The concept of drilling leakage ring, that under the same conditions, flat circle area is greater, the greater the amount of leakage, and the influencing factors of drilling leakage ring size analyses, through the change of drilling around the coal permeability, gas seepage theory, the solution derived from the equation of the drill hole leakage volume and gas concentration the combination of the previous chapter content is calculated at a time of drilling gas concentration formula.3) based concept of concentration, concentration and concentration into the instant, think the key size is to adjust the instant concentration to change the concentration of drilling, and analyze the influencing factors. Mainly drilling diameter, plastic ring the radius of the sealing supporting force, the effective length of sealing section, negative pressure drainage.4 process) put forward flow acceleration, pointed out that the gas concentration within the borehole with negative pressure increased or decreased, mainly from The ratio of W depends on the amount of gas emission and gas leakage of drilling acceleration acceleration, when W1, increase the negative pressure can improve the gas drainage hole sealing unit concentration, reduce the pumping pressure will reduce the gas sealing unit extraction concentration; W1, improve the drainage pressure will reduce the concentration of gas sealing element the reduction of negative pressure drainage will improve the gas drainage concentration sealing unit, this paper puts forward the W to optimize the gas concentration method and the proposed.5) principle of active supporting type sealing was developed based on the bag type grout sealing device, and the engineering application, experiment proved compared with the existing polyurethane sealing method of new type of sealing method can improve the gas concentration of drilling and drainage flow.6) designed a test device for coal seam mining and gas concentration parameters change with the pumping pressure, and different coal seam gas pressure Analysis of borehole gas concentration changes with negative pressure pumping experiment, and analysis of leakage volume changes with pumping negative pressure recovery experiment shows that the borehole gas drainage concentration with vacuum extraction to improve the trend mainly depends on the gas pressure, the motion state of tiny particles of borehole sealing and leakage of the crack, and puts forward the the optimum vacuum extraction, in gas extraction process, vacuum extraction is not possible, nor is it as low as possible, but there is an optimal vacuum extraction, and the optimal pumping classified mining pressure, think through the search for the best extraction concentration pumping negative pressure can adjust the gas. At the highest extraction concentration and reduce the leakage of.7 as much as possible) combined with the theoretical analysis and laboratory experiments, put forward the concept of gas drainage and mining pipeline concentration automatic control warning system, system The use of computer, sensor and actuator can detect and adjust the action of the negative pressure drainage pipeline to the best state. According to the action of the executive mechanism design of three sets of plans, by comparison, and finally determines the electric valve actuator as the action plan. The main control system, sensor, and the action mechanism the discussion, completed the selection of hardware design, PLC program, touch screen interface design of PC software interface design, and the online test of.8 comprehensive) for the installation of gas concentration testing automatic control warning system in coking coal group nine mountain mine, and studied the system according to the preset value engineering the practice site geological conditions of coal seams and drilling hole sealing parameters, search out the best experimental roadway drainage negative pressure and the best extraction concentration, proves the correctness of theoretical analysis and system The reliability and practicability of the system.

【学位授予单位】：河南理工大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TD712.6

【相似文献】