Multi-functional multi-field coupling seepage experiment device and testing method thereof

Patent metadata

Field	Value
Publication number	US-10801942-B2
Application number	US-201716306030-A
Country	US
Kind code	B2
Filing date	Sep 6, 2017
Priority date	Aug 16, 2017
Publication date	Oct 13, 2020
Grant date	Oct 13, 2020

Abstract

A multi-functional multi-field coupling seepage experiment device includes a device body, a stress field control system, a temperature field control system, a fluid loading control system and a fluid seepage measurement system. The present invention further discloses seepage experiments performed on tight gas, shale gas, tight oil, shale oil, natural gas hydrate and geothermal heat in a multi-field coupling state of a temperature field, a stress field, a pore pressure field and a seepage field.

First claim

What is claimed is:

1. A multi-functional multi-field coupling seepage experiment device, comprising a device body, a stress field control system, a temperature field control system, a fluid loading control system and a fluid seepage measurement system;
an experiment chamber; a bearing platform, a rock sample, a pressure head, a metal washer, a heat shrinkable tube and a cold bath are provided inside the device body; the bearing platform is provided inside the experiment chamber; an upper end and a lower end of the rock sample are provided with a temperature sensor respectively; an axial extensometer and a radial extensometer are provided on the rock sample; the rock sample is placed on the top of the bearing platform and sleeved with the heat shrinkable tube; the heat shrinkable tube is provided in the cold bath; the pressure head extends downward into the experiment chamber; a rubber ring and the metal washer are connected to the bottom of the pressure head in sequence; the metal washer is in contact with the top surface of the rock sample; an upper pipeline is provided on the metal washer; a port of the upper pipeline is in contact with the upper surface of the rock sample; a valve Vm located in the experiment chamber is connected to the upper pipeline; a lower pipeline is connected to the lower part of the device body; a valve Vx located in the experiment chamber is connected to the lower pipeline; a resistance wire is provided on the inner wall of the experiment chamber;
the stress field control system comprises a confining pressure hydraulic pump and an axial pressure hydraulic pump, wherein a valve Vj and a pressure gauge A are connected to a liquid outlet of the confining pressure hydraulic pump in sequence; the other end of the pressure gauge A is communicated with the experiment chamber; a valve Vk and a pressure gauge B are connected to a liquid outlet of the axial pressure hydraulic pump; the other end of the pressure gauge B is communicated with a hydraulic flow passage inside the pressure head;
the temperature field control system comprises an air conditioning oil refrigerator, a heating furnace and a thermometer A, wherein a valve Vi is connected to a cooling medium outlet end of the air conditioning oil refrigerator; the other end of the valve Vi is communicated with the cold bath; the heating furnace is connected with the resistance wire; the thermometer A is connected with the temperature sensor;
the fluid loading control system comprises a constant-flux pump, a first intermediate container, a second intermediate container, a third intermediate container and a fourth intermediate container, wherein a valve Va is connected between an outlet end of the constant-flux pump and each of the intermediate containers; a valve Vb, a valve Vc, a valve Vd and a valve Ve are connected to outlet ends of the first intermediate container, the second intermediate container, the third intermediate container and the fourth intermediate container respectively; a pressure gauge C is connected between each of the other ends of the valve Vb, the valve Vc, the valve Vd and the valve Ve and the valve Vx; a valve Vn and a vacuum pump are connected to a node between the pressure gauge C and the valve Vx in sequence;
the fluid seepage measurement system comprises a back pressure valve connected to the valve Vm, wherein the back pressure valve is connected with the valve Vm; two branches are connected to the other end of the valve Vm, wherein one branch consists of a valve Vf, a gas meter and a gas chromatograph connected in sequence; the other branch consists of a valve Vg, a gas-liquid separator, a liquid meter and a liquid chromatograph connected in sequence; a valve Vh is connected between the node between the gas meter and the valve Vf and the gas-liquid separator; a valve Vy is connected between an inlet end of the back pressure valve and an outlet end of the valve Vn;
the multi-functional multi-field coupling seepage experiment device further comprises a console that is connected with the axial extensometer, the radial extensometer, the air conditioning oil refrigerator and the heating furnace.

2. The multi-functional multi-field coupling seepage experiment device according to claim 1 , wherein the device body comprises a base, a housing and a top cover, wherein the top cover and the base are fixedly connected to the upper end and the lower end of the housing respectively.

3. The multi-functional multi-field coupling seepage experiment device according to claim 1 , wherein a back pressure pump is connected to the back pressure valve.

4. The multi-functional multi-field coupling seepage experiment device according to claim 1 , wherein a thermometer B is connected to an outlet of the back pressure valve.

5. A testing method for the multi-functional multi-field coupling seepage experiment device according to claim 1 , comprising the following steps:
S1, a test of replacing tight gas or shale gas with carbon dioxide under multi-field coupling, which includes the following test steps:
S1(1), preparing a tight sandstone or shale rock sample to be tested; compounding tight gas or shale gas in a first intermediate container, compounding carbon dioxide in a second intermediate container, inspecting various components of the device and their connection relationships and adjusting them to initial working states;
S1(2), sleeving the rock sample to be tested with a heat shrinkable tube; installing a temperature sensor to the upper end and the lower end of the rock sample respectively; installing an axial extensometer and a radial extensometer on the rock sample; placing the rock sample on the top of a bearing platform; placing a metal washer and a rubber ring on the top of the rock sample in sequence, then connecting the rubber ring to a pressure head, and closing an experiment chamber;
S1(3), closing a valve Vb, a valve Vc, a valve Vd, a valve Ve, a valve Vm and a valve Vy; opening a valve Vn and a valve Vx; turning on a vacuum pump and a heating furnace; vacuumizing the experiment chamber by the vacuum pump to further vacuumize the rock sample; heating, by the heating furnace, the experiment chamber with a resistance wire to further heat the rock sample; forming a temperature field when a reading on a pressure gauge C is stable and a reading on a thermometer A is stable;
S1(4), turning off the vacuum pump and closing the valve Vn; opening the valve Va, the valve Vb and a constant-flux pump; pumping, by the constant-flux pump, the tight gas or shale gas in the first intermediate container into the experiment chamber through the valve Vb and the valve Vx in sequence to make the rock sample saturated, wherein, the rock sample is filled with gas, thereby forming a pore pressure field and a seepage field; opening a valve Vj and a valve Vk at the same time, and introducing hydraulic oil into the experiment chamber by a confining pressure hydraulic pump; applying, by the hydraulic oil, a radial pressure to the heat shrinkable tube and further a radial pressure to the rock sample; pumping hydraulic oil into a hydraulic flow passage of the pressure head by an axial pressure hydraulic pump; applying, by the pressure head, an axial force to the rock sample, till numerical values of a pressure gauge A, a pressure gauge B and a pressure gauge C reach experimentally set pressure values; turning off the hydraulic pump to form a stress field;
S1(5), observing the reading of the thermometer A; proceeding to the next step when a numerical value of the thermometer A is stabilized to an experimentally set numerical value;
S1(6), closing the valve Vb, opening the valve Vc, and pressurizing the constant-flux pump; pumping, by the constant-flux pump, the carbon carbonate in the second intermediate container into the experiment chamber through the valve Vc and the

Assignees

• Univ Southwest Petroleum

Inventors

• Ou Chenghua
• Zhu Haiyan
• Liu Qingyou
• Li Chaochun

Classifications

• G01N15/082 Primary

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