利用氮气泡沫解除煤层气水平井堵塞的研究和应用

The Study on Block Removal in Horizontal Wells by Using Nitrogen Foam and Its Application

煤层气井在生产过程中随着液体和气体向井筒流动,会把煤层裂隙中的煤粉携带到近井地带,造成堵塞,使产气量下降。普通的套管完井可以进行二次压裂等方式进行解堵,而水平井大多为裸眼完井或筛管完井,水平段发生堵塞难以清理。通过对水平井堵塞的多种原因进行分析,并对氮气泡沫液体体系解堵可行性进行了论证,指出关键点,以实例证明使用氮气泡沫液体体系进行煤层气水平井解堵具有很好解堵效果和市场价值。

In the production process of CBM wells,the liquid and gas flow to the wellbore,the coal powder in the seams of coal seams is carried to the areas near the wellbore,which would cause a blockage and decrease gas production.Ordinary casing completions can be carried out for a secondary fracturing,but the horizontal wells are mostly open hole or screen pipe completions,it is difficult to remove the block in the horizontal sections.This paper analyzes the causes of blocking in the horizontal wells,demonstrates the feasibility of block removal with the nitrogen foam system and points out the key factors.It is proved that the use of nitrogen foam liquid system for block removal in CBM horizontal wells has a good effect and market value.