Study On Production Well Corrosion Inhibitor Huff And Puff Technology

As the development of oil field, water ratio increases continuously, production well corrosion becomes more and more serious, the need to resolve oil well corrosion is more and more urgent. This paper raises a new method to reduce production well corrosion, which is the huff and puff technique of corrosion inhibitor in formation. The said technique involves injecting corrosion inhibitor into high water cut production well, this corrosion inhibitor will enter high permeability zone of formation, and then selective plugging off agent is injected to block off corrosion inhibitor in high permeability zone. When the water displacing oil gets close to production well, the corrosion inhibitor will flow out for a long time attaining the aim to slow down production well corrosion. Production well corrosion inhibitor with preferable corrosion control effect in market is evaluated by weight-loss method and electrochemistry method, and then a kind of inhibitor named BS-X with the best corrosion control effect is obtained. Diphase titrate method is used to analysis the effective concentration of BS-X and its high temperature stability is investigated. The result shows that its high temperature stability is well. The block agent used for corrosion inhibitor huff and puff is studied, including gelling time and stability of different crosslink system gel, and then different gelling time composition of block agent is obtained. Other matting working fluids are also studied, including ahead fluid, isolate fluid and subsequent fluid. Corrosion inhibitor huff and puff is stimulated with physical models in laboratory, including inhomogeneous plate model and visualization models. It is shown that blocked corrosion inhibitor produces slowly with low concentration by water flood. This will fulfill the aim to slow down oil well corrosion in a long period. Matting technique is studied, providing laboratory study basis for the field conduct of this technology.