煤层气地面工程优化简化研究

Study on optimization and streamlining of coalbed methane surface facilities

国内煤层气经过十几年的发展,相关企业经历从试验区到大规模整装气田的开发,已逐步掌握煤层气生产规律并取得了一定的建设经验。中国煤层气行业现已步入低成本、规模化开发阶段,为适应其建设进度、质量和经济效益的需要,有必要开展优化简化研究。通过收集国内外煤层气项目相关资料,开展现场调研及技术对标,结合国内煤层气地面工程技术现状、存在问题,提出优化简化措施:1)采气管道边缘井场互联局部成环,集气站之间连通进站采气管道汇管,采气管道关键位置设置阀门;2)采气管道推广使用PE100 SDR21/SDR26系列管材;3)煤层气井口采用电动调节阀;4)井场取消计量阀组;5)井场集水管线设置清扫口;6)集气站进站取消重力分离或者旋流分离器,改为过滤分离器;7)集气站压后设置过滤分离器,收球筒后设置清管分离器;8)集气站压缩机优先选择螺杆压缩机;9)压缩机和三甘醇脱水装置之间设置冷却装置;10)井场和集气站数据传输采用光缆方式。上述优化简化措施已在沁水气田樊庄、郑庄、马必等区块和鄂东气田保德、大宁、韩城等区块煤层气项目中得到有效推广,实现了降本增效。

After more than ten years of development,coalbed methane related companies in China have experienced different development phases from pilot test phase to large-scale integrated gas field development stage and have gradually mastered the production pattern of coal-bed methane and obtained relevant development experience.China's coalbed methane industry has entered the stage of low-cost and large-scale development,so it is necessary to carry out optimization and streamlining research in order to meet the triple needs of rapid development pace quality and economic benefits.By collecting relevant data of coalbed methane projects at home and abroad,we have carried out field research and technical benchmarking,taking into consideration the current technical skill level and existing problems of domestic coalbed methane surface facilities technology.As a result,the following optimization and streamlining measures are proposed:1)To enhance flexibility and reliability,well sites surrounding thegas production pipeline should be connected to each other to form a ring;gas gathering pipelines entering neighboring gas gathering stations are inter-connected to form a manifold so that the gathering station facilities can be interchanged;isolation valves are installed at key positions of gas production pipelines;2)Promote the use of PE100 SDR21/SDR26 series pipes as gas gathering pipelines;3)Electric control valve is to be used at coalbed methane wellhead;4)The wellsite metering valve set is removed;5)A cleaning port is provided for the well site water collection pipeline;6)The gravity separation or cyclone separator at the inlet of gas collecting station is replaced with filter separator;7)The filter separator is installed downstream of the compressor of the gas gathering station;pigging separator is installed downstream of pig receiver;8)Screw compressor is recommended for gas gathering station;9)A cooling unit is provided between the compressor discharge and the triethylene glycol dehydration system;10)Optical fiber is used for data transmission between the well site and gas gathering station.The above optimization and streamlining measures have been effectively implemented in coalbed methane projects in Fanzhuang,Zhengzhuang and Mabi blocks of Qinshui Gas Field and Baode,Daning and Hancheng blocks of Eastern Hubei Gas Field,resulting in cost reduction and efficiency increase.