压缩机降压采气系统压损分析与适应性研究

Pressure loss analysis and compatibility research on compressor depressurized
gas production system

耿新中¹ 刘学凯¹ 张文娟¹ 娄乐勤² 青聪³

中国石化中原油田分公司天然气产销厂，河南 濮阳 457061 中国石化中原油田分公司技术监测中心，河南 濮阳 457001 中国石化中原油田分公司采油五厂，河南 濮阳 457001

降压采气是气田开发后期稳产和提高采收率的重要途径，效果主要取决于其能够形成的地层压力降幅。但受气藏物性不同和天然气可压缩性的影响，降压采气形成的地层压降与压缩机形成的地面压降有明显的差异。文中从降压采气基本原理出发，结合天然气地层渗流、井筒与地面管流基本理论，以降压前后气井生产系统沿程压力损失特征分析为基础，对影响降压采气效果的各种因素进行了剖析，提出应该以经济极限产量或井筒临界携液气量为依据，从而合理确定降压采气起始与失效地层压力，取得了无须苛求极限降低压缩机进口压力的认识，得出了压缩机降压采气更适用于弹性产率大、高渗不产液或低渗产液气藏的结论。

In the later period of natural gas field development, compressor depressurized gas production is an important way for stable production and high recovery, the effect is mainly depended upon the formation pressure decrease range which it can form. Influence by the different reservoir permeability and the natural gas condensability, the formation pressure decrease is different from the compressor pressure decrease. According to the basic principle of the depressurized gas production and the elementary theories of natural gas stratum transfusion, well chamber and ground pipe flow, using the pressure loss characteristic analysis around gas well production system as a foundation, this article analyzes the various factors which affects the effect and proposes that the determination of the outset and the expiration formation pressure should be based upon the economic limit output or the critical well chamber liquid flow quantity and no excessive demands are needed to reduce the compressor inlet pressure, the depressurized gas production is more applicable for the reservoirs with big elastic production rate, higher stratum permeability, or low stratum permeability with liquid producing.

10.6056/dkyqt201506035