强抑制性聚胺类页岩抑制剂NH-1的性能研究

为了解决在膨润土含量较高的地层钻井过程中出现井壁失稳的技术难题,根据添加页岩抑制剂抑制膨润土水化膨胀和分散的机理,通过分子设计研制了一种强抑制性聚胺类页岩抑制剂NH-1,并采用X-射线衍射(XRD)法和扫描电镜(SEM)法研究了NH-1对膨润土的抑制机理,采用岩心滚动回收实验、抗二级膨润土污染实验、相对抑制率实验、防膨胀率实验评价了NH-1的抑制效果.结果表明:膨润土被3.0%NH-1溶液浸泡烘干后,蒙脱石001晶面层间距从12.11增加到13.77;在2.5%NH-1溶液中,一次岩心回收率为89.52%,相对于清水提高了83.32%;在2.5%NH-1溶液中,当膨润土添加量为20%时,Φ600读数为9,而同等条件下在清水中Φ600读数超出了仪器量程;0.5%NH-1溶液对10%的膨润土浆的相对抑制率达到98.5%;2.5%NH-1溶液防膨率为80.37%.围绕NH-1聚胺抑制剂开发的聚胺防塌钻井液体系在四川高庙4井3 375～3 786 m井段进行了先导性试验,划眼时间仅仅只有20.8 h,只占总钻进时间的3.98%,成功解决了高庙4井井下井壁失稳的技术难题.

Performance study of a shale inhibitor polyamine NH-1 with excellent inhibitive property

In order to prevent borehole instability in the drilling of high clay formation,a shale inhibitor polyamine NH-1 with excellent inhibitive property was prepared.The inhibition mechanism of this polyamine was studied by XRD and SEM.Inhibitive performance of polyamine NH-1 was evaluated by cuttings roller recovery experiment,antipollution ability experiment of bentonite,relative inhibition rate experiment and expansion rate experiment.The results indicate that,when the bentonite was marinated by NH-1 solution of 3.0% and then dried,the lattice spacing of 001 crystal surface of smectite increases from 12.11  A to 13.77  A;when in NH-1 solution of 2.5%,the primary cuttings roller recovery rate is 89.52%,it is increased by 83.32% compared with in water;in NH-1 solution of 2.5%,the number of 600 is 9 under the condition of 20% bentonite adding amount,while in water,the number of 600 is out of measurement range of instrument under the same condition;relative inhibition rate of 0.5% NH-1 solution to 10% bentonite slurry is 98.5%;anti-swelling rate of 2.5% NH-1 solution is 80.37%.Based on polyamine NH-1,a new polyamine-based anti-sloughing drilling fluid system was developed,and the pilot test was carried out in the drilling interval of 3 375 ～ 3 786 m of Gaomiao-4 well in the western Sichuan.The test result shows that,reaming time is only 20.8 h,and it is only 3.98% of the whole drilling time.The application of the shale inhibitor NH-1 successfully solves the borehole instability of the well.