A steam huff and puff recovery method assisted by air injection and carbon dioxide

Abstract

The invention provides a steam-huff-and-puff oil production method assisted by injection of air and carbon dioxide. The method includes the following steps that (1) an injection well and an adjacent well are arranged, and the oxygen content of casing pipes of the injection well and the adjacent well is measured online; (2) when the online measured oxygen content of the injection well casing pipe is higher than an explosion point, nitrogen and / or carbon dioxide are / is injected into the injection well, and the content of oxygen content of the injection well casing pipe, which is lower than the explosion point, is an injection finishing point; (3) the gas mixture of air and carbon dioxide is injected till the total reaches a design discharge, and after the injection is finished, a carbon dioxide slug killing well is used, and then steam is injected; or a gas mixture slug of air and carbon dioxide is injected, a steam slug is injected, then the gas mixture slug and the steam slug are injected continuously, circularly and alternately till the gas mixture slug injection total reaches the design discharge, and after the circular injection is finished, the carbon dioxide slug killing well is used; (4) the well is soaked till the pressure inside the well reaches a normal pressure, and blowout production is carried out.

Description

technical field [0001] The invention relates to an oil recovery method assisted by air injection and carbon dioxide steam huff and puff, which belongs to the technical field of oil exploitation. Background technique [0002] Liaohe Oilfield is an oilfield dominated by heavy oil. With the prolongation of the steam huff and puff period, the deficit in the formation increases, and the production decline also accelerates; moreover, the large amount of water in the formation also seriously reduces the efficiency of heat energy utilization, which increases the development cost and deteriorates the mining benefit. Therefore, it is becoming more and more important for the follow-up development of heavy oil fields to explore new technologies and new production models to enhance the recovery factor and oil-gas ratio of heavy oil and super heavy oil. [0003] The patent application with the application number 200910011365.3 discloses a "formation catalytic oxidation heavy oil thermal ...

AI Technical Summary

Problems solved by technology

In the past, due to the influence of the price of carbon dioxide and its main function is to reduce the viscosity of crude oil, its high solubility in crude oil can easily achieve the effect of miscible flooding, so its energy-enhancing effect is not very large. Its application scale is limited

At present, the technology of incinerating oil reservoirs has been applied on a large scale in some blocks of Liaohe Oilfield, which has played a pivotal role in fully utilizing the production capacity of the reservoir. The large amount of tail gas produced by incinerating oil reservoirs has a high content of carbon dioxide, but only part of it has been recycled, and the surplus part is Exhausted into the atmosphere, which has brought adverse effects on the environment

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