关键词: 铬微凝胶, 交替调驱技术, 聚丙烯酰胺

Abstract: Chromium micro gel system is a kind of three dimensional network structural gel which generated from cross-linking reaction among molecules of chrome cross-linking agent and partial hydrolyzing polyacrylamide. Gelling time can be controlled by adjusting ligandnumber of chrome cross-linking agent, while gelling intensity and depth can be controlled by adjusting system concentration, which can meet the demand of different reservoirs. The polymer flooding control technology not only improves the intake profile and restrains polymer breakthrough even polymer cross flow by chromium micro gel slug, but also displaces remaining oil in mid-low permeability oil layers by polymer slug. It also pushes forward the chromium micro gel slug into the deep reservoir, which avoids the weakness of mobility control by single profile control and achieves the best effect of blocking up meanwhile flowing. Field application in Sanan development area of Daqing Oilfield showed that after injecting chromium micro gel slug, the input profile was improved and water ratio was decreased by more than 1%. What's more, water cut backed up so slowly that the speed of back-up was effectively controlled. Remarkable results of increasing oil and decreasing water have been given by profile control alternately.

Key words: chromium micro gel, alternating flooding technology, polyacrylamide