聚胺水基钻井液特性实验评价

Experimental Evaluation on Polyamine Water-Based Drilling Fluid

室内合成的聚胺强水化抑制剂SD-A可有效抑制黏土水化分散,与国外同类产品Ultrahib性能相当。聚胺水基钻井液配方为:4%膨润土浆+3%SD-A+0.5%SD-E+1%PAC-LV+0.3%XC+3%SD-506。与聚合醇、阳离子、KCl/聚合物钻井液相比,二级膨润土在聚胺水基钻井液中的膨胀率最小,岩屑回收率最高,表明聚胺水基钻井液抑制页岩水化分散能力强。聚胺水基钻井液120℃热滚16 h前后的流变性能稳定,热滚后动塑比为1.07,高于油基钻井液。在400 mL聚胺水基钻井液中分别加入144 g NaCl、8 g CaCl2和80 g劣土后,体系流变性发生不同程度的改变,而滤失量变化较小,其中CaCl2对体系流变性影响最大。结果表明聚胺水基钻井液的抗污染能力较强。屈曲硬度实验、耐崩散实验和黏结实验等新型实验方法表明,聚胺水基钻井液的抑制性接近甚至超过油基钻井液,清洁润滑性优良,其EC值为12 g/L,符合环保要求。另外,简要分析了聚胺水基钻井液的抑制机理。

The hydration and dispersion of clay could be inhibited effectively by a synthesized polyamine strong hydration inhibitor SD-A as foreign product Ultrahib.The formula of polyamine water-based drilling fluid was established： 4% base slurry,3% SD-A,0.5% SD-E,1% PAC-LV,0.3% XC and 3% SD-506.Compared with polymeric alcohol drilling fluid,cation drilling fluid and KCl/polymer drilling fluid,the shale swelling rate was the least for polyamine water-based drilling fluid and the cutting recovery was the highest,indicating its excellent shale hydration inhibition.The rheology of the system was stable before and after 120℃ hot rolling,showing good temperature resistance.The value YP/PV of polyamine water-based drilling fluid after hot rolling was of 1.07,which was higher than oil-based drilling fluid＇s.After adding 144 g NaCl,8 g CaCl2 and 80 g solids into 400 mL polyamine water-based drilling fluid respectively,the rheology of the system had changes in varying degrees,while the API filter loss changed little.CaCl2 affected the rheology greatest among the three pollutants.The results demonstrated that polyamine water-based drilling fluid was anti-polluted.These drilling fluids were characterized by bulk hardness test,slake durability test and accretion test and others.The results showed that the inhibition of polyamine water-based drilling fluid approached to or even surpassed that of oil-based drilling fluid.The system was also clean and lubricant.The EC50 of polyamine water-based drilling fluid was of 12 g/L which met the environmental requirement.Furthermore,the inhibition mechanism was briefly analyzed.