SSMA和AMA对钻井液降黏作用效果研究

Effect of SSMA and AMA on Reducing the Viscosity of Drilling Fluid

李骑伶 叶德展 刘 侨 代 华 张 熙

LI Qi-Ling YE De-Zhan LIU qiao DAI Hua ZHANG Xi

为探讨聚合物钻井液降黏剂结构与性能的关系，本文以对苯乙烯磺酸钠、丙烯酸、马来酸酐为原料，过硫酸铵为引发剂合成了对苯乙烯磺酸钠-马来酸酐（SSMA）和丙烯酸-马来酸酐（AMA）两种聚合物降黏剂，研究了二者在钻井液中的降黏效果和耐温抗盐性能。研究结果表明，含磺酸基团的SSMA和含羧基的AMA均能有效地拆散钻井液中的黏土颗粒结构、降低钻井液的黏度和切力，但二者在钻井液中遇盐（NaCl）、钙（CaCl2）与高温条件时表现出较复杂的行为规律。AMA在淡水钻井液、盐水钻井液中的降黏作用比SSMA的强；当加量较低时（≤0.3%）在钙处理钻井液的降黏作用比SSMA强，但加量较高（>0.3%）时，AMA在钙处理钻井液中的降黏效果降低甚至起增黏作用。与AMA相比，SSMA处理的钻井液抗NaCl污染能力较差，抗CaCl2污染能力较强。AMA的降黏作用受高温老化的影响较SSMA小，表现出更好的耐温性能。

In order to study the relationship between the structure and properties of the copolymer thinners, SSMA and AMA thinners were synthesized using sodium p-styrene sulfonate, maleic anhydride and acrylic acid as raw materials, ammonium persulfate (APS) as initiator. The viscosity reduction performance, temperature resistance and salt tolerance of them were investigated. The results showed that SSMA and AMA, with sulfonic acid group and carboxyl group respectively, could efficiently break the links between clay particles in the drilling mud, leading to the decline of the viscosity and the shearing force. While the behaviors of SSMA and AMA became complicated at high temperature or with adding certain amount of NaCl and CaCl2 into the drilling mud. Compared with SSMA, AMA showed the better thinning performances in both fresh-water and saline-based drilling fluid and played more effectively role in the calcium-based mud with lower dosage range(≤0.3%) , but when the dosage was higher than 0.3%, the property of viscosity reduction of AMA became worse even increased the viscosity. The drilling fluid treated with SSMA showed the poorer resistance to NaCl pollution and stronger resistance to CaCl2. The performance of high temperature resistance of AMA was better than that of SSMA.