摘要
研究了酸度和温度等因素对ＰＡＭ／Ｃｒ（ＮＯ３）３系统成冻时间的影响以及Ｃｒ３＋水解聚合过程的特点，结合高价金属离子交联ＰＡＭ的机理，探讨了酸度影响ＰＡＭ／Ｃｒ（ＮＯ３）３系统成冻时间的原因。结果表明：降低ＰＡＭ／Ｃｒ（ＮＯ３）３系统的ｐＨ值和温度能有效地延长成冻时间，可以满足采油作业对延缓成冻的需要；Ｃｒ３＋离子的水解聚合作用较弱，速度慢，是决定成冻时间的控制步骤。
The gelation time of an aqueous polyacrylamide/chrominum nitrate system is determined at pH values 3.60—4.16 and temperatures 30℃, 45℃ and 70℃. It is shown that the gelation of this system can be effectively delayed by lowering its pH and temperature to meet the requirements in oilfield chemical operations. The mechanisms of delayed gelation are discussed in terms of hydrolytic polymerization of Cr(Ⅲ) compound into polynuclear hydroxyl briedged complex Cr(Ⅲ) ions which crosslink the polymer. The reaction hydrolysis/complexation is weak and slow and appears to be the controlling step in gelation of the polymer system.
出处
《油田化学》
CAS
CSCD
北大核心
1997年第2期135-138,共4页
Oilfield Chemistry
关键词
酸度
硝酸铬
聚丙烯酰胺
延缓成冻
冻胶
采油
Aqueous Polyacrylamide/Chrominum Nitrate System, Polyacrylamide/Chrominum Gel, Delayed Gelation, Acidity Adjustment, Reaction Mechanisms
