琼东南深水钻井液体系研究

Research on Deep-water Drilling Fluid System in Southeast of Hainan

分析了琼东南深水区域的地质和复杂情况,确定该区域潜在着海底页岩稳定性差、安全密度窗口窄、钻井液低温增黏、浅层气和天然气水合物等情况。在研究深水钻井液低温流变性能和深水钻井液中水合物生成的影响因素的基础上,通过室内实验构建了一套适合琼东南深水钻井的水基强抑制环保型钻井液。室内评价结果表明,该体系的低温流变性能好;抑制能力比油基钻井液略差,但远高于其他水基钻井液;能抑制天然气水合物的生成,保证在1 500～2 000 m水深条件下静置5 d无水合物生成;抗污染能力强,满足琼东南深水钻井的需要。

There is much oil and gas resource in southeast of Hainan,but the deep-water drilling technology of China cannot meet demands of the exploration of that.Conditions of lithology and drilling problems are analyzed,some difficulties are encountered in this block,such as gas hydrate,drilling fluid thickened at low temperature and shale collapsing at the sea bottom.A kind of water-based environmental protection high inhibition drilling fluid systemused for deep-water drilling is developed in laboratory based on research of low-temperature drilling fluid rheology and technology of inhibiting gas hydrate,which can meet demands of deep-water drilling in Southeast of Hainan.