Research on Efficient Polymer Dissolving Technology for Hydrophobically Associating Polymer Flooding on Offshore Platform

Abstract

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).

Development and Application of Chemical EOR Technologies in China Offshore Oil Fields

“…By adjusting the type and proportion of functional monomers, the salt and temperature resistance ability of polymers was improved. The polymer at lower concentrations could significantly reduce the viscosity of the heavy oil and significantly improves the fluidity of the heavy oil [12][13][14]. Above polymer had been injected in several pilot wells in Bohai oil field since December 2018.…”

Exploration of Super-Gravity Rapid Dissolution Method of Polymer for Offshore Oil Repellent

“…Due to the high viscosity of crude oil, strong formation shear capacity [2,17], and high mineralization of formation water in offshore fields such as Bohai [18], hydrophobic associative polymer AP-P4 can better meet the needs of viscosity building ability [19,20], shear resistance and salt tolerance under the conditions of offshore oilfield injection and polymerization than conventional linear polymers [21][22][23]. The polymer dispensing system used in onshore fields is no longer suitable due to the large volume of single well dispensing in offshore fields [24,25], the limited space and carrying capacity of offshore platforms [2,26], and the long dissolution time of polymers [27,28].…”

Optimization Design and Analysis of Polymer High Efficiency Mixer in Offshore Oil Field

“…The mechanism of hydrophobic association improves the property of the polymer solution but increases the difficulty in dissolving it in water [12,13]. This is because a small amount of hydrophobic groups on the macromolecular chain of hydrophobically associating polymer will block the entry of water molecules, thus prolonging the dissolution time of the polymer [14,15]. In the limited offshore platform space, it is difficult to fully mix and dissolve hydrophobically associating polymer under the polymer dissolving process device prepared in the land oilfield [16][17][18].…”