氮气辅助吞吐工艺在八面河油田的应用研究

Applied Research of Nitrogen-aided Huff and Puff Technology in Bamianhe Oilfield

八面河油田沙四段一直以来就是该油田热采产量的主要产区,近年来随着热采轮次的增加,该区产量出现大幅度的下滑。影响多轮次递减因素主要有:储层薄;采出程度高,地层能量不足;泥质含量高;汽窜。运用氮气辅助吞吐技术在八面河油田沙四段的试验取得了良好的效果。首先从套管注入氮气5.5×104 m3,然后开始注汽,注汽开始后从油管注入高温起泡剂,同时从套管注入氮气,直至高温起泡剂注完,增能助排作用明显。

Sha-4 Member has been the major thermal recovery area in Bamianhe Oilfield.With increase of thermal recovery turns in recent years,its yield is reduced by a large margin.Thin reservoir,high recovery percent of reserves,short formation energy,high shale content and steam channeling are the main factors for multi-cycle degression.Experimental application of nitrogen-aided huff and puff technology in Sha-4 Member achieves a good result of energy increase and nitrogen assisted drainage.5.5×104 m3 nitrogen is injected from the casing before steam injection begins.Then high-temperature foamer is injected from the oil pipe after steam injection begins and meanwhile nitrogen is injected from the casing until high-temperature foamer injection finishes.