耐200 ℃高温、低伤害压裂液稠化剂

Fracturing Fluid Thickener with High Temperature Resistance and Low Damage

罗志锋 张浩飞 赵立强 何 杰 扶浩然 赵金明 闫朝宗

LUO Zhifeng ZHANG Haofei ZHAO Liqiang ZHAO Liqiang FU Haoran ZHAO Jinming YAN Chaozong

为提高压裂液稠化剂的耐高温、低伤害性能，以丙烯酰胺（AM）、甲基丙烯酰氧乙基三甲基氯化铵（DMC）、 2-丙烯酰胺基-2-甲基丙磺酸（AMPS）和N-乙烯基吡咯烷酮（NVP）作为共聚单体，采用水溶液自由基聚合法制得压裂液稠化剂（ADAN）。通过单因素变量法优选了制备条件，分析了ADAN的结构和稳定性，评价了含ADAN压裂液的耐温耐剪切性、降阻性、静态携砂性和破胶性。结果表明，最佳的共聚物配比及反应条件为：单体占总反应体系质量的 20%、4 种单体（AM、AMPS、DMC、NVP）的物质的量比为 14∶2∶3∶1、引发剂（质量比为 1∶1 的K2SO3和 NaHSO3）用量占体系总质量的 0.4%、pH 值为 7、反应温度为 45 ℃、反应时间 8 h。在此条件下制得的ADAN热稳定性良好，在 40～260 ℃下的质量损失约为 10%。0.8% ADAN与有机锆交联剂、高温稳定剂亚硫酸钠、破胶剂过硫酸铵等配制的压裂液具备良好的耐温耐剪切性、降阻性、静态携砂性和破胶性。在 200 ℃、剪切速率为170 s-1下剪切140 min 后的黏度仍高于90 mPa·s；在100～160 L/min 的流量变化区间内，降阻率由48%上升至 63%；陶粒在压裂液中静置 12 h后的沉降距离为6.3 cm，沉降速度为0.875×10-2cm/min；破胶后的残渣含量为86 mg/L。ADAN压裂液可耐200 ℃高温，并对储层的伤害较小，满足现场施工及地层需要。

In order to improve the high temperature resistance and low damage performance of fracturing fluid thickener，the fracturing fluid thickener （ADAN） was prepared by aqueous free radical polymerization using acrylamide （AM）， methylacryloxyethyl trimethylammonium chloride （ DMC ） ， 2-acrylamido-2-methylpropanesulfonic acid （ AMPS ） and N-vinylpyrrolidone（NVP）as monomers. The preparation conditions were optimized by single factor variable method，the structure and stability of ADAN were analyzed，and then the temperature and shear resistance，resistance reduction，static sand carrying and breaking properties of the fracturing fluid containing ADAN were evaluated. The results showed that the optimum copolymer ratio and reaction conditions were obtained as follows：20% monomer in total mass of reaction system，14∶2∶3∶1 the molar ratio of 4 monomers（AM，AMPS，DMC，NVP），0.4% initiator（K2SO3 and NaHSO3 with mass ratio of 1∶1）in total mass of reaction system，7 pH value，45 ℃ reaction temperature，8 h reaction time. ADAN prepared under these conditions had good thermal stability. The mass loss was about 10% at 40—260 ℃ . The fracturing fluid prepared with 0.8% ADAN，organozirconium crosslinking agent，high temperature stabilizer sodium sulfite and gel breaker ammonium persulfate had good temperature and shear resistance，resistance reduction，static sand carrying and breaking properties. The viscosity was still higher than 90 mPa·s after shearing for 140 min at 200 ℃ and 170 s-1. In the flow range of 100—160 L/min，the resistance reduction rate increased from 48%to 63% . The settling distance and settling velocity of ceramic particles were 6.3 cm and 0.875 × 10-2 cm/min after standing in fracturing fluid for 12 h. The residue content after gel breaking was 86 mg/L. ADAN fracturing fluid could withstand the high temperature of 200 ℃，meanwhile the damage to the reservoir was less，which met the needs of field construction and formation.

10.19346/j.cnki.1000-4092.2024.03.003