Research Of Strong Penetration And Long-acting Blocking Removal Technology In Polymer Injection Wells Of Sabei Oil Field

In the history or polymer flooding development of Daqing Sabei oilfield, the accumulate amount of polymer injected has increased. The adsorption and detention of polymer in the reservoir pore channel has block up the layer. The parameters of injection wells get more deterioration year by year. And it affects the effects of polymer flooding development. In the last few years, Daqing Sabei oilfield has achieved some results from blocking removal by fracturing, chemical, germ. There is still some problems such as blockage cause unclear, fracturing costs high, the validity of chemical pluging removal is short. So an efficient, long-term pluging removal technology of polymer injection well is urgent needed.By theoretical research, chemical analysis and instrumental analysis, this thesis analyzed the stem component of polymer injection well of Daqing Sabei oilfield, and had made clear of the blocking mechanism. On the basis of blocking mechanism, this thesis studied the main and addition agent of blocking remover, and defined the two blocking remover formulationsThrough the polymer injection well core simulation experiments, the effect of the two blocking remover formulations was evaluated and be found more effective than the blocking remover which is constantly used in well site,at the same time, the injection order an ratio were defined. After blocking removal, the permeability recovery rate is more than sixty percents, and the blocking rate, which is created by following polymer injection, decreased from more than eighty percents to low than fifty percents. So it costs less and has enduring and high effect on the polymer injection well of Daqing Sabei oilfield.