Compound type anti-gas-channeling agent for carbon-dioxide flooding

Abstract

The invention provides a compound type anti-gas-channeling agent for carbon-dioxide flooding. The compound type anti-gas-channeling agent for carbon-dioxide flooding is prepared from the following raw materials: polymer gel and precipitate base fluid; on the basis that the total mass of the polymer gel is 100%, the polymer gel is prepared from the following raw materials: 0.5-1% of polyacrylamide, 0.1-0.5% of an organic metal crosslinking agent, 0.5-2% of a resin crosslinking agent, 0.05-0.2% of a stabilizing agent and the balance of simulation formation water; on the basis that the total mass of the precipitate base fluid is 100%, the precipitate base fluid is prepared from the following raw materials: 2-15% of a precipitation solution and the balance of simulation formation water. The compound type anti-gas-channeling agent for carbon-dioxide flooding is good in anti-gas-channeling effect.

Description

technical field [0001] The invention relates to an anti-gas channeling agent, in particular to a composite type anti-gas channeling agent for carbon dioxide flooding, and belongs to the technical field of petroleum exploitation. Background technique [0002] Carbon dioxide flooding technology has the advantages of good injection performance, wide application range, low oil displacement cost, and significant enhanced recovery in low-permeability oilfield development. At the same time, it can also slow down the greenhouse effect caused by carbon dioxide. Therefore, carbon dioxide flooding technology has become an important global One of the oil recovery methods. [0003] However, in the process of carbon dioxide gas flooding, due to the influence of reservoir heterogeneity, mobility difference, density difference and other factors, the gas gradually forms a fingering phenomenon in the formation, which leads to the occurrence of gas channeling. The gas channeling phenomenon wi...

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Problems solved by technology

[0005] Among them, water-air alternation technology and carbon dioxide foam sealing channeling technology are widely used, and some results have been achieved in mine applications. However, frequent alternate injection of water and air will increase the water saturation of the oil layer and reduce the contact efficiency of carbon dioxide and crude oil. , making it difficult to form a miscible zone, thus reducing the oil displacement efficiency

[0006] The foaming and stabilizing properties of the surfactants used in the carbon dioxide foam technology will be seriously affected under the condition of high temperature and high salinity. In addition, carbon dioxide has a large solubility in formation water, foam and gel, so the carbon dioxide molecules in the above The concentration diffusion in the system is very obvious, resulting in poor blocking effect of carbon dioxide foam, thickened foam, and gel sealing system on carbon dioxide

[0007] However, the precipitation system used in the chemical reaction has disadvantages such as poor injectivity and uncontrollable plugging position in low-permeability reservoirs.

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