摘要
针对单一、低透气性突出煤层消突困难、煤巷掘进速度低的问题,提出了多点控制水力压裂快速消突方法。以鹤壁六矿为试验矿井,通过理论分析多点控制水力压裂煤层破裂过程,结合适用于鹤壁六矿瓦斯地质条件的RFPA^(ZD)-Integrated软件进行水力压裂数值模拟,研究了多点控制水力压裂增透快速消突机理,确定了适合六矿2123回风巷的压裂设备型号及压裂工艺参数。结果表明,多点控制水力压裂效果要优于常规水力压裂,试验工作面实施控制压裂措施后,瓦斯抽采浓度、瓦斯流量和掘进速度均有大幅提高,达到了快速消突的目的。
This paper is aimed at introducing the experience of our way on how to apply the multipoint control hydraulic fracturing technology to the single coal seam exploration of No.6 Mine,Hebi,Henan.Since the single coal seam of the aforementioned No.6 Mine,is known for its low permeability prone to gas outbursts,it is difficult for the miners to take general measures to prevent the outbursts of the seam even during the coal dug up under transportation.In order to solve the problem,we have been trying to adopt the multipoint control hydraulic fracturing technology to the case study of ours.As a matter of fact,the said control method is different from the traditional ones in that it includes four parallel boreholes,which can be used to guide the cracks in extending in the direction of the control holes.The fractures come to pass only under the condition of the surrounding rocks of coal being compressed or cracked.What is more,since the traditional hydraulic fractures tend to occur only with one drill,the coal seam may get fractured at very high hydraulic pressures.In accordance with the situation,it is possible for the multipoint control hydraulic fracturing technology to bring the fracture of the coal seam at low hydraulic pressure.The results of our experiment indicate that the point type control fracturing helps to increase the permeability of the coal seam and the efficiency of the gas drainage.And,for the research purpose,first of all,we have carefully studied the fracturing mechanism and analyzed the influential factors on the fracturing effect,such as the regularity of the deformation and fracture development surrounding the boring-holes.In addition,we have made detailed analysis of how the fractures develop in the holes and learn to determine the proper layout parameters of the hydraulic fracturing with the help of a numerical simulation software known as ＂RFPA2D-Integrated＂.And,finally,we have made out the original coal seam deformation process and the regularity of the given deformation surrounding the borehole under the ground stress as well as the likely influential factors.And,afterwards,the numerical simulation results help us to work out the proper construction technology parameters to meet the geological conditions and propose the multipoint control hydraulic fracturing technology and the necessary measures concerned to prevent the gas drainage.The results of simulation indicate that,in comparison with the original fracturing method,the multipoint control hydraulic fracturing technology we have proposed and developed is in a position to increase the gas drainage concentration to a remarkable degree.Thus,it can be concluded that the average concentration of the gas extraction and gas flowing rate has been pushed to a new height after being fractured,which suggests that there is a great potentiality for the multipoint control hydraulic fracturing technology to be developed for its successful application for the successful prevention from the low temperature outburst in the coal seam exploration.
出处
《安全与环境学报》
CAS
CSCD
北大核心
2015年第6期39-44,共6页
Journal of Safety and Environment
基金
国家"十二五"科技重大专项(2011ZX05040-005)
关键词
安全工程
多点控制水力压裂
消突机理
煤层变形
快速消突
safety engineering
multipoint control hydraulic fracturing
elimination outburst mechanism
coal seam deformation
rapid elimination outburst
