油井用抗高温冻胶堵剂体系研究

STUDY ON HIGH TEMPERATURE RESISTANT GEL PLUGGING AGENT SYSTEM FOR OIL WELLS

为了解决传统高温堵剂长效性不足、强度低的问题,从主剂类型及主剂、交联剂、促进剂、除氧剂浓度等因素确定了高温冻胶堵剂体系,采用扫描电镜和热重分析对其进行了表征。实验结果表明,该高温冻胶堵剂体系优化配方为:8%木质素磺酸钠+3.5%交联剂JL+3%促进剂CJ+0.3%除氧剂;当体系pH=8~10、温度为120~180℃时,成胶强度均能达到Ⅰ级;该木质素磺酸钠冻胶堵剂体系胶结强度高,体系抗温可达250℃,属于聚合物交联冻胶。

In order to solve the problems of insufficient long-term effect and low strength of traditional high-temperature gel plugging agents,the high-temperature gel plugging agent system was determined according to the type and concentration of the main agent,cross-linking agent,promoter,and deoxidizer,etc.The sodium lignosulfonate gel plugging agent system was characterized and analyzed using scanning electron microscopy(SEM)and thermogravimetry(TGA).The experimental results show that the optimal formula of the high-temperature gel plugging agent system contains 8%main agent sodium lignosulfonate concentration,3.5%cross-linking agent JL,3%accelerator CJ,and 0.3%deoxidizer.When the pH of the system is 8-10 and the temperature is 120-180℃,the gel strength can reach grade I.SEM and TGA test results show that the sodium lignosulfonate gel plugging agent system has high bonding strength and temperature resistance up to 250℃,which belongs to crosslinked polymer gel.