Method and device for simulating strata pressure in three-dimensional simulation test for producing oil by injecting multicomponent thermal fluid

Abstract

The invention relates to a method and a device for simulating a strata pressure in a three-dimensional simulation test for producing oil by injecting multicomponent thermal fluid. The method comprises a boosting process and a pressure releasing process, wherein in the boosting process, a pressure of a model main body is increased gradually so as to inflate to increase a pressure of a hyperbaric chamber; in the pressure releasing process, the pressure of the model main body is reduced gradually so as to exhaust to reduce the pressure of the hyperbaric chamber; when a differential pressure is less than 10 KPa, a programme automatically inflates the hyperbaric chamber; a differential pressure set value is between 40 and 100 KPa; when a test pressure is between 0 and 5 MPa, a hysteresis quantity set value is between 10 and 15 KPa; when the test pressure is between 5 and 10 MPa, the hysteresis quantity set value is between 5 and 10 KPa; and when the test pressure is between 10 and 20 MPa, the hysteresis quantity set value is between 1 and 5 KPa; an ambient pressure of the air is uniform and stable and the air can effectively prevent fluid channeling of a displacing medium; the pressurecontrol precision is high; the automation degree is high and the operation is simple and convenient; and the hysteresis quantity is set so as to prevent frequent movement of a valve and prolong the service life of equipment.

Description

Technical field: [0001] The invention relates to a high-temperature (temperature 350° C.) high-pressure (pressure 20 MPa) three-dimensional simulation test formation pressure simulation method and device for oil recovery by injecting multi-component thermal fluid. Background technique [0002] The high-temperature and high-pressure three-dimensional simulation test device for multi-component thermal fluid injection can carry out the research on the technology of improving oil recovery by using various methods such as steam injection, gas injection, and hot solvent injection under the conditions of reservoir pressure 20MPa and temperature 350°C, which can be reproduced to the greatest extent. The real reservoir development status is an important and most powerful research method to solve the reservoir production mechanism and optimize the reservoir development plan indoors. In the physical simulation test, it is necessary to provide a certain pressure environment for the mode...

AI Technical Summary

Problems solved by technology

However, the confining pressure of the liquid still has the following disadvantages: 1) due to the small compressibility of the liquid, a small volume change may cause a large pressure change (this change may be due to temperature changes, deformation or leakage of the pressure container) Most of them belong to uncontrollable factors), so the pressure control accuracy is low and the stability is poor. This phenomenon is especially serious under high pressure, which cannot meet the requirements of high temperature and high pressure three-dimensional simulation test; 2) The thermal conductivity of the liquid is large, giving the model body It is very difficult to keep warm, and sometimes it is even necessary to add a vacuum insulation layer, which will make the system structure more complicated

[0015] 1) Low precision and poor stability of pressure control: Due to the small compressibility of liquid, a small volume change may cause a large pressure change (this change may be caused by temperature changes, deformation or leakage of pressure-bearing containers , most of which are uncontrollable factors), resulting in low pressure control accuracy and poor stability. This phenomenon is especially serious under high pressure, which cannot meet the requirements of high temperature and high pressure three-dimensional simulation tests;

[0016] 2) The thermal conductivity of the liquid is large, which brings great difficulties to the heat preservation of the model body, and sometimes even needs to add a vacuum insulation layer, which will make the system structure more complicated;

[0017] 3) The pressure control method is not flexible: in this technology, the confining pressure cannot be flexibly adjusted automatically according to the model pressure, and can only be controlled by a single pressure value set manually

However, it must be ensured that the confining pressure of the liquid is higher than the model pressure during the test, otherwise the displacement medium will channel in the model

During the test, when the model pressure rises, if the set value is not adjusted in time, there will be a risk of channeling

[0018] 4) Only setting the confining pressure at a certain value will easily lead to frequent actions of the pump in and out of the hydraulic pump

[0020] Gas confining pressure, the nitrogen confining pressure used in this technology, the specific control method has not been mentioned

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