抗温抗污染油基钻井液乳化剂的研制及在阳101区块的应用

Development of Anti-temperature and Anti-pollution Emulsifier for Oil-Based Drilling Fluid and Its Application in Yang101 Block

针对页岩气地层埋深不断增加和其它工作液因施工不当侵入油基钻井液体系中导致其性能下降,且目前市场上的乳化剂不能很好的解决此问题,开展抗温抗污染乳化剂的研究。以天然松香酸、多烯多胺、马来酸酐为主要原料,通过酰胺化、Diels-Alder两步法反应合成一种抗高温抗污染乳化剂NY-4。对NY-4进行结构表征、性能评价及机理分析。红外图谱分析表明松香酸、多烯多胺及马来酸酐均参与了反应,使乳化剂具有抗高温抗污染结构基团。乳化剂加量为3%~5%时可配制出油水比为60:40至90:10、密度为1.50~2.71 g/cm^(3)的油基钻井液,该剂配出的油基钻井液抗温可达230℃;密度为2.3 g/cm^(3)时,在230℃下静置5 d,沉降因子SF小于0.51;抗岩屑污染为10%,抗现场水基钻井液、水泥浆前置液和水泥浆侵污为8%。通过在阳101H2-8井的应用,该乳化剂能够在185℃温度下保持钻井液性能的稳定,协助钻井工程刷新了当时中国石油页岩气井深、储层埋深4 000 m以深水平位移最长两项记录。

Aiming at the continuous increase of shale gas formation burial depth and the problem that the stability of oil-based drilling fluid system decreases due to the invasion of other working fluids, and currently, the emulsifiers on the market can’t solve this problem, the research on high temperature and pollution resistance emulsifiers is carried out. Using natural rosin acid, polyene polyamine and maleic anhydride as main raw materials, a high temperature and pollution resistant emulsifier NY-4 was synthesized by amidation and Diels-Alder two-step reaction. Its structure characterization, performance evaluation and mechanism analysis of NY-4 were carried out. Infrared spectrum analysis showed that rosin acid, polyene polyamine and maleic anhydride were all involved in the reaction, which made the emulsifier had temperature-resistant and anti-pollution structural groups.When the amount of emulsifier is 3%~5%,oil-based drilling fluid with oil-water ratio of 60:40 to 90:10 and density of 1.3 g/cm^(3)~2.3 g/cm^(3) can be prepared, and the temperature resistance can reach 230 ℃.When the density is 2.3 g/cm^(3),it is left standing at 230 ℃ for 5 d, and the sedimentation factor SF is less than 0.51.The resistance to debris pollution is 10%,and the resistance to on-site water-based drilling fluid, cement slurry pad and cement slurry intrusion is 8%. The application of the agent in Well Yang 101H2-8 achieved good results, setting the two records of the longest horizontal displacement below 4 000 m of drilling well depth and reservoir buried depth of PetroChina shale gas at that time.