Method and device for sampling produced fluid of oil reservoir for microbial flooding

Abstract

The invention relates to a method and a device for sampling a produced fluid of an oil reservoir for microbial flooding. The technical scheme comprises the following steps of: (1) test and control of the temperature and pressure of the oil reservoir; (2) anaerobic treatment for the sampling device; (3) high-temperature and high-pressure separation of oil, gas and water; (4) anaerobic and high-pressure sampling of the oil, the gas and the water; (5) on-line test of oil, gas and water samples; and (6) processing and remote transmission of oil, gas and water test results. The invention has the advantages of solving the problem of the sampling of oil, gas and water mixtures under high-temperature, high-voltage and anaerobic conditions, ensuring that materials cannot diffuse on the spot during the sampling so as to protect on-site environment, ensuring that recovered crude oil and gas can be effectively utilized, ensuring the accuracy and reliability of parameter testing of the produced fluid of the oil reservoir of the microbial flooding, improving the accuracy of microbial community structures by over 30 percent and the accuracy of oxidation-reduction potential by over 40 percent, and providing a reliable theoretical basis for the ecological regulation and control of the oil reservoir of the microbial blooding.

Description

technical field [0001] The invention relates to the technical field of microbial oil recovery, in particular to a method and device for sampling oil reservoir production fluid for microbial flooding under high temperature, high pressure and anaerobic conditions. Background technique [0002] Microbial Enhanced Oil Recovery refers to the technology that utilizes microorganisms (mainly bacteria, archaea) and their metabolites to increase crude oil production and recovery. Compared with other tertiary oil recovery technologies, microbial technology is applicable It has the characteristics of wide range, simple process, good economic benefits, and no pollution, and has good application prospects, so it has received more and more attention. At present, three types of technologies have been formed: microbial single well wax prevention, microbial stimulation and microbial flooding. [0003] At present, the test items of the produced fluid in the microbial flooding process main...

AI Technical Summary

Problems solved by technology

In the current traditional sampling process, the pressure of the sample will be suddenly released to atmospheric pressure, and there is no insulation measure, and it will be exposed to the air to destroy the original anaerobic environment. Therefore, the disadvantages of this method are:

This method will cause the oxygen in the air to dissolve into the produced water, increase the dissolved oxygen, and make the measured oxidation-reduction potential value higher;

[0006] (3) The oil-water mixture obtained from the field needs to go to the laboratory for oil-water separation and pre-treatment before testing, so not only the time-consuming results in inaccurate test results, but also the intermediate links are likely to cause sample contamination;

[0007] (4) During the on-site sampling process, the gas and part of the produced liquid are directly discharged, causing environmental pollution

The existing problem is that the device samples the suspension under normal temperature, normal pressure and open conditions, which cannot meet the requirements of high temperature, high pressure and closed sampling.

Patent 200910142194.8 ("oil-water two-phase oil phase sampling method and its special equipment") introduced a method of using polypropylene fiber as a separator and using a peristaltic pump to continuously extract the oil phase. The problem is that the device can only Carry out oil-water two-phase separation under normal temperature and normal pressure conditions, which cannot meet the requirements of high pressure and airtight sampling, and at the same time waste is discharged to pollute the environment

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