摘要
考虑煤层气解吸、扩散、渗流规律,建立了煤储层基质孔隙和裂隙双重介质的气、水两相排采数学模型,对刘家区复杂地质条件下的水平井排采煤层气进行了数值模拟研究,并结合经济效益约束方程,研究了储层中垂向井位对水平井产能、经济效益的影响,从水平井长度、井筒直径方面对水平井结构进行了优化设计,最后确定了优化后水平井的排采强度。结果表明:模拟结果与现场监测生产曲线吻合较好,表明所建数学模型和地质模型是可靠的;水平井的产气量和经济效益与储层的渗透率密切相关,渗透率最大的层位产能、效益最好;存在一个产能最优水平段长度、最优井筒直径。
In this paper, we would like to bring about an analysis of the parameter optimization and rational production intensity for the horizontal wells in Liujia CBM block. For our study purpose, we have collected actual geological data of Liujia, including the reservoir depth, the formation thickness, the permeability and the porosity. All the said comphcated geological conditions of the block of coalmine can be reflected in the geological model we have established, includ ing the fault structure, the intrusive igneous rock and the fold. Under such complicated geological conditions, we have worked out a numer icM simulation model about the high rank CBM horizontal well. At the same time, we have also made a comprehensive study of the econom ic benefits due to the constraint equations, the actual influence of the reservoir in the vertical position on the production of the horizontal wells. Wellbore structure here can be regarded as an optimized de sign from the aspects of the horizontal well length and the wellbore di ameter due to the final confirmation of the optimized horizontal line strength. The simulation results we have obtained also indicate that they are well in accord with the field monitoring production curve, which shows that the established mathematical model and the estab lished geological model are both reliable and therefore applicable forprediction of the high rank CBM horizontal wells. What is more, the gas production and the economic benefit of the horizontal wells are closely linked with the permeability of the reservoir, which implies that, the greater the permeability of the horizontal production capaci tyis, the greater the economic benefit of the well will be. And so, it is also true that the greater the bore length is and the bigger the well bore diameter is, the better the productivity of the horizontal well will be. However, if the well bore length is short, the fracturing area will be in turn small. And, then, less solution to breathe will be in na ture. On the contrary, the greater the lengt
出处
《安全与环境学报》
CAS
CSCD
北大核心
2014年第4期57-62,共6页
Journal of Safety and Environment
关键词
安全工程
水平井
优化设计
排采强度
产能
safety engineering
horizontal well
optimum design
production intensity
productivity
