1.College of Chemistry and Chemical Engineering,Southwest Petroleum University;2.Hadde Oil and Gas Management Area of Tarim Oilfield Company;3.Jiqing Oilfield operation area of Xinjiang Oilfield Company, Jimsar
Sichuan province Science and Technology Planning Project（2019YJ0315），Open Fund Project of Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province（YQKF202001）
為改善油藏儲層非均質性，提高酸化施工作業效果。以丙烯酰胺（AM）、磺酸鹽單體（HSY）、十八烷基二甲基烯丙基氯化銨（DMAAC-18）為功能性單體，合成并研究了一種表面活性劑-聚合物自組裝酸化轉向用聚合物AHD，利用FTIR和GPC對產物結構進行了表征。通過AHD與十八烷基三甲基氯化銨（STAC）自組裝形成酸化轉向體系。90 ℃下，AHD加量為1.0 %、STAC加量為0.2 %（以HCl溶液總質量為基準），無需交聯劑轉向酸黏度從3 mPa·s增加到288 mPa·s，鮮酸黏度低于非交聯聚合物轉向酸，容易注入地層。油的加量為1.0 %時，可使殘酸破膠后黏度低于10 mPa·s，保留了黏彈性表面活性劑型轉向酸在遇油自動破膠，利于返排的優點。通過TEM與DLS研究機理發現Ca2+會促進表面活性劑-聚合物自組裝體系形成更加龐大的聚集體，進而使轉向酸得以轉向。
In order to optimize the non-homogeneity of the reservoir to improve the effectiveness of acidizing operations, a self-assembled acidizing steering polymer named AHD, was synthesized in this study. Acrylamide (AM), sulfonate monomer (HSY) and octadecyl dimethyl allyl ammonium chloride (DMAAC-18) were used as functional monomers to obtain polymer AHD, which was characterized by FTIR and GPC. AHD could form steering acid system with trimethylstearylammonium chloride（STAC） by self-assembly. The viscosity of this system could increase from 3 mPa·s to 288 mPa·s without crosslinking agent when the addition of AHD and STAC was 1.0 % and 0.2 % (based on the total mass of HCl solution) at 90 ℃. Fresh acid was easier to introduce into the formatio because it had a lower viscosity than the non-crosslinked polymer steering acid’s viscosity. With 1.0 % oil addition, the viscosity of the spent acid after gel breaking was less than 10 mPas, maintaining the benefit of viscoelastic surfactant steering acid could gel break automatically in the situation of oil for backflow. According to the mechanism of the TEM and DLS investigations, Ca2+ encouraged the development of bigger aggregates in the surfactant-polymer self-assembly system, which allowed the steering acid to be diverted.