油田用延时性高黏凝胶制备方法研究

基于改性淀粉凝胶于调剖堵水、封堵、钻完井等方面优异的使用性能及应用前景。以淀粉、丙烯酰胺(AM)为原料,偶氮二异丁腈(AIBN)为引发剂,利用淀粉同烯类单体进行接枝共聚,通过交联剂来实现共价键交联,在实验室条件下合成一种适用于中、高温油藏,成胶时间延时至2 h内可控的高强度的改性淀粉凝胶。研究了引发剂的用量、交联剂的用量、反应温度、p H值对胶体成胶性能(体系黏度和成胶时间)的影响。结果表明:在引发剂质量分数介于0.04%~0.06%,交联剂质量分数在5.1%左右,反应温度为80℃,体系p H为10时所制得的聚合物胶体性能最佳,其体系黏度对应为1 950×103 m Pa·s。

Research on Preparation Method of High Viscosity Delayed Gel for Oil fields

Modified starch gel has excellent performance and application prospect in profile controlling/water shutoff technology and formation sealing, drilling and completion. In this paper, using starch and acrylamide (AM) as raw materials, azodiisobutyronitrile (AIBN) as initiator, via starch graft copolymerization with alkene monomer, through covalent cross-linking by crosslinking agent, a new type of high strength modified starch gel was synthesized under the condition of laboratory. Effect of initiator dosage, crosslinking agent dosage, and reaction temperature and pH value on the gel properties (viscosity and gelling time) was investigated. The results show that, when the initiator mass fraction is 0.04%~0.06%, crosslinking agent mass fraction is 5.1%, reaction temperature is 80℃ and pH is 10, prepared polymer gel has the best performance, and the system viscosity can be up to 1 950×103 mPa?s .