调剖用部分水解聚丙烯酰胺-柠檬酸钛缓交联体系

PHPAM/TITANIUM CITRATE AQUEOUS SYSTEMS OF DELAYED CROSSLINKING FOR PROFILE MODIFICATION IN WATER-INJECTING WELLS

本文提出了一种用于注水井调剖的部分水解聚丙烯酰胺-柠檬酸钛缓交联体系。柠檬酸钛大大延缓了部分水解聚丙烯酰胺的交联反应速度,使体系粘度随时间缓慢增加。适当配方的体系粘度达到1.8×10~3mPa·s需72小时。本文介绍了柠檬酸钛的制备方法、研究了pH值、Ti^(4+)浓度、部分水解聚丙烯酰胺浓度及水解度、温度、水的矿化度对交联反应速度的影响。

In laboratory the titanium citrate is prepared from TiCl_4 and Na citrate in molar ratio 1:1 and used for crosslinking PHPAM in aqueous solutions with delay in time. The optimum system selected consists of PHPAM with MM 4×10~6 and hydrolysis degree 5% in 10000mg/l and Ti citrate in 6000mg/l(calculated on Ti^(4+)) and reaches apparent viscosity some 1900mPa·s at pH=4.0 after 72 hr standing at 70℃. It is shown that the crosslinking rate of PHPAM/Ti citrate systems increases with decreasing pH value and hydrolysis degree of PHPAM and with increasing polymer concentration, temperature, water salinity and minerality and decreases with Ti^(4+) concentration diviating from optimum, when other parameters maintaining invariable. This permits make the delay time period controllable. The PHPAM/Ti gelling systems are investigated for use to modify injection profile of water wells