Conventional gellants used in acid stimulation have poor temperature stability and limited retar-ding capacity, and frequently a large amount of gellant is needed in acid stimulation. A new gellant is now synthesized using reverse emulsion polymerization in laboratory in the following conditions: raw material: N, N-dimethyl acrylamide, diallyl dimethyl ammonium chloride, and AMPS; temperature 45 ℃; oil/water ratio 2:3 ; concentration of compound emulsifier 5%; total concentration of monomer 40%; total concen-tration of oil soluble initiator, 0. 15% that of monomer; nitrogen. A purified sample of this gellant was characterized using infrared spectra. Laboratory study showed that CAT-3 is ready to dissolve in acids and has good viscosifying capacity at lower concentration. It also has good shear thinning property and salt tol-erance. CAT-3 is suitable for use in acid stimulation at 130 ℃ and has satisfactory acid-rock reaction retar-dation effect. Acid retention is 40% after 120 min of application, meaning that the flow conductivity of the acid-eroding fractures can be improved and the effective working distance of acid can be extended, resulting in a deep acidification. Moreover, CAT-3 has good compatibility with other aeid stimulation additives and produces no secondary damage to formations it works on.%针对常规酸化胶凝剂用量大、耐温性能差、缓速能力有限的缺点,分别以一定量的N,N-二甲基丙烯酰胺、二甲基二烯丙基氯化铵和2-丙烯酰胺基-2-甲基丙磺酸为原料,在45℃、油水比为2:3、复合乳化剂总浓度为5%、单体总浓度为40%、油溶性引发剂总浓度为单体总浓度的0.15%和氮气保护的条件下,采用反相乳液及油溶性引发剂氧化还原体系聚合的实验方法,合成出了耐高温酸化用胶凝剂CAT-3,并对其纯化试样进行了红外光谱图表征.室内综合性能评价结果表明:胶凝剂CAT-3具有快速的酸溶能力和良好的酸溶效果,用量少且增黏能力强,剪切稀释性能好,抗盐能力强,适用于130℃左右的酸化施工地层;具有理想的酸岩反应缓速性能,120 min后残酸的浓度保留率仍保持在40%以上,有利于增大酸液溶蚀裂缝的导流能力和延长酸化的有效作用距离,达到深度酸化地层的目的;另外,CAT-3与常用酸化添加剂的配伍性能好,不会对地层产生二次伤害,有利于酸化作业过程中储层的保护.
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