Indigenous microorganism oil flooding method

Abstract

An oil extraction method driven by substrate microorganism, the first stage: aerobic fermentation stage, oxybiontic hydrocarbon-oxidizing bacterium and facultative anaerobe of hydrocarbon-oxidizing bacterium are activated at the near zone of the water injection well. Because of being partial oxidation of hydrocarbons, it produces alcohol, fatty acid, surfactant, CO2, biological polysaccharide and other product; on one hand these substance is base oil releaser, on the other hand it is as nutrient source of anaerobe including methanogen; The second stage: anaerobic fermentation stage, methanogen is activated in the deep part of anoxic oil pool, producing CO4, CO2 and other matter which increases oil fluid and increases recovery after the matter dissolving in water; In the process, the proportion between isotope light methane produced by biology and general methane is increased.

Description

technical field [0001] The invention belongs to an oil recovery method, in particular to an original microbial flooding oil recovery method. Background technique [0002] Indigenous microorganisms refer to relatively stable microbial communities existing in oil reservoirs. The original microbial oil flooding method is a biological oil recovery technology applied to oil reservoirs developed by water injection for more than 2 years. During the water injection process of these oil reservoirs, various microorganisms in the surface water were brought into the oil reservoirs unintentionally, and some bacteria already existed during the formation of the oil reservoirs. Due to the differences in the types of bacteria, some bacteria do not adapt to the environment and die; The main factor for mass reproduction is the lack of sufficient nutrients, such as nitrogen sources and phosphorus sources. There are two main reasons for the analysis: ①The number of native microorganisms, espe...

AI Technical Summary

Problems solved by technology

There are two main reasons for the analysis: ①The number of native microorganisms, especially the increase in the number of anaerobic bacteria is relatively low (compared to aerobic bacteria); ②The activation of beneficial bacteria is not enough, and substances such as surfactants and polysaccharides cannot be reproduced in large quantities. , can not achieve the purpose of significantly degrading crude oil, improving the reservoir ecosystem and oil-water properties, and improving the fluidity and recovery of remaining oil

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