In order to apply the technique of polymer flooding to the offshore oilfield, some contraventions (the large well spacing, the high salinity formation water, the narrow production platform space, the limited load capacity, the slow dissolution of hydrophobically associating polymer, the voluminous existing polymer injection equipment) must be faced. In order to resolve the problems, a study on the efficient polymer dissolving technology for hydrophobically associating polymer flooding on offshore platform was conducted. The principle of polymer rapid dissolution was analyzed on its restrictive factors. By comprehensive utilization of multi-disciplinary angle of studying from polymer materials, fluid mechanics, et al, the efficient polymer dissolving technology was formed by means of compulsory stretching and water logging for polymer molecular chains, and break through the "bottlenecks" of polymer rapid dissolution. The designed dispersing & dissolving equipment cut down the polymer dissolution time from 60 min to 40 min. Meanwhile, the auto-unloading device, metering device, curing system, injection system, and automatic control system were optimized. Compared with the original equipment, the novel one’s occupied area and operating weight decreased by 21% and 37%, respectively. The efficient injection allocation technology was applied to the polymer flooding pilot testing in Bohai bay so as to provide key technology and equipment support for cumulative incremental oil 395×104 m3 (up to June, 2014), incremental output value 12 billion yuan (estimated by the barrel oil price $90).
A novel binary flooding system of a biobased surfactant and hydrophobically associating polymer with ultralow interfacial tensions
