中国深部煤层气资源丰富,是煤层气下步勘探开发的重要领域,但深部煤层气资源地质条件更加复杂,工程配套难度大,实现高效开发极具挑战性,攻克深部煤层气效益开发的技术瓶颈,对于推动深部煤层气资源高效动用具有重要意义。以延川南深部煤层气开发调整实践为例,系统分析了早期产建过程中面临的五大难题和挑战：①储层非均质性强,富集高产主控因素不明;②立体资源未能有效动用,储量动用程度低;③开发井网部署模式单一,高应力低渗区单井控制面积小;④深层煤层气储层可改造性差,早期常规水力压裂难以实现长距离有效支撑;⑤传统排采制度达产周期长,经济效益差。在此基础上,经过反复探索实践,通过“五个转变”形成了深部煤层气高效开发的新理念及关键技术：①产建模式从整体推进向有利区精准圈定转变;②开发层系从单层向合层开发转变;③井网部署由单一直井向“直井+水平井”复合井网转变;④储层改造从常规压裂向有效支撑压裂转变;⑤排采制度从缓慢长期向优快上产转变。立足于“五个转变”,现场生产实践显示新井产建效益显著提升,直井产量由1 800 m³/d提升至10 000 m³/d,水平井产量由10 000 m³/d提升至20 000~50 000 m³/d,取得了较好的开发效果,延川南煤层气田高效开发调整对策的突破对于深部煤层气效益开发具有重要的示范及带动意义。

The deep underground place in China is rich in coalbed methane resources, so that it is an important field of further exploration and development of coalbed methane. However, the geological conditions of deep coalbed methane resources are more complex, and it is different to deploy supporting technologies for engineering, so there is great challenge to realize efficient development. Overcoming the technical bottle-neck of efficient development of deep coalbed methane is of great significance to promote the efficient utilization of deep coalbed methane resources. Taking the development practice of deep coalbed methane in southern Yanchuan CBM Field as an example, five challenges faced in the process of early productivity construction are systematically analyzed: ① The reservoir heterogeneity is strong, and the main controlling factors for enrichment and high yield are unknown; ② The vertical resources need to be further evaluated, and the reserve utilization degree is low; ③ The deployment mode of well pattern is single, and the control area of single well in high stress and low permeability area is small; ④ The modification of the deep coalbed methane reservoir is poor, so it is difficult to achieve long-distance effective support by conventional hydraulic fracturing in the early stage; ⑤ The traditional drainage system has a long production cycle which is resulted in poor economic benefits. On this basis, through repeated exploration and practice, a new concept and key technology for efficient development of deep coalbed methane resources have been formed by “five transformations”: ① The overall productivity construction will change to accurate delineation of favorable areas; ② The development layer system changes from single layer to composite layer; ③ The well pattern deployment has converted from single vertical wells to the mixing well pattern of “vertical well + horizontal well”; ④ Reservoir reconstruction has changed from conventional fracturing to effective support fracturing; ⑤ The drainage system has changed from “slow and long-term” to “efficient increase of production”. Based on the “five transformations”, the production and construction benefits of new wells have been significantly improved, the daily output of vertical wells has increased from 1 800 m³/d to 10 000 m³/d, and that of horizontal wells increased from 10 000 m³/d to 20 000~50 000 m³/d. Good development results have been achieved, and the breakthrough of adjustment countermeasures for efficient development of southern Yanchuan CBM Field has important demonstration and driving significance for the benefit development of deep coalbed methane.