System and method for testing non-linear seepage characteristics of fluid in low-permeability porous media

A technique for porous media and characteristic testing, which is applied in suspension and porous material analysis, measurement devices, permeability/surface area analysis, etc. Long time and other problems, to achieve the effect of ensuring accuracy and stability, saving experimental testing time, and small changes

Active Publication Date: 2011-12-28
PETROCHINA CO LTD
View PDF5 Cites 28 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] The inventor found in the process of realizing the present invention that the ring pressure loaded on the rock core increases with the increase of temperature, and the phenomenon is more obvious, because the time required for each experimental point test of...

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • System and method for testing non-linear seepage characteristics of fluid in low-permeability porous media
  • System and method for testing non-linear seepage characteristics of fluid in low-permeability porous media
  • System and method for testing non-linear seepage characteristics of fluid in low-permeability porous media

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0047] Example 1: Discrete Data Measurements at High Displacement Pressures

[0048] Wash the core to be tested with oil in advance, dry it, and saturate it with simulated formation water;

[0049] Before the experiment started, all valves were closed;

[0050] The intermediate container 6 is filled with simulated formation water, the prepared rock core is placed in the core holder 17, the valves 15, 16, and 19 are opened, and the ring pressure is applied to the core in the core holder 17 by the ring pressure pump 20, Monitor the ring pressure value from the ring pressure gauge 14 until it reaches the standard, then close the valves 16 and 19;

[0051] According to the needs of the experiment, initially set a pressure value for the pressure reducing valve 2, and then set an accurate experimental pressure value through the high-precision gas regulator valve 4;

[0052] Open the valves 3 and 8 to make the flow flow unimpeded, and after confirming that there is no leak, remove ...

Embodiment 2

[0059] Example 2: Discrete Data Measurements at Low Displacement Pressures

[0060] Wash the core to be tested with oil in advance, dry it, and saturate it with simulated formation water;

[0061] Before the experiment started, all valves were closed;

[0062] Place the prepared rock core in the core holder 17, open the valves 15, 16, 19, use the ring pressure pump 20 to load the ring pressure on the rock core in the core holder 17, and monitor the ring pressure value from the ring pressure gauge 14 , until the standard is reached, close the valves 16 and 19;

[0063] According to the needs of the experiment, open the required one of the valves 9g, 9h, 9i, 9j, such as the valve 9j, at this time, ensure that the other valves 9g, 9h, 9i are closed, start the peristaltic pump 9f, at this time, the constant pressure pipe 9e constant water overflow;

[0064] Open the valve 12 to make the low-range pressure sensor 11 effective;

[0065] Observe whether the process is unimpeded, ...

Embodiment 3

[0072] Example 3: Non-linear Curve Drawing

[0073] Using a series of pressure, displacement and time values ​​measured in Example 1 and Example 2, and using data processing tools, the relationship curve of "flow velocity-pressure gradient" can be drawn. Specifically, in the "flow rate-pressure gradient" relationship curve, since the opening pressure of the glass thin tube of the photoelectric micro-flowmeter 18 is atmospheric pressure, the pressure gradient is equal to the ratio of the reading of the high-range pressure sensor 10 or low pressure sensor 11 to the length of the rock core ,which is:

[0074] grad P = P L

[0075] gradP is the pressure gradient (unit: MPa / m); P is the reading of the high-range pressure sensor 10 or the low pressure sensor 11 (unit: MPa); L is the core length (unit: m). The flow velocity is equal to the ratio of the fluid volume in the glass capillary 18a whose length ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention provides a test system and method of fluid non-linear percolation characteristics in a low-permeability porous media. The test system comprises a plurality of test branches, wherein, each test branch comprises a displacement pressure output unit for providing different pressures to transfer displacing fluid to a test core, a pressure measuring unit for the pressure of the displacingfluid output by the displacement pressure output unit, a flowing unit for accommodating the test core and providing ring crush to the test core, a flow measuring unit for measuring the flow of the displacing fluid flowing through the test core, and a thermostatically control unit for providing a constant ambient temperature for the flowing unit and the flow measuring unit. By adopting the thermostatically control unit, the influence of variation in temperature to the test results is eliminated, so that the test results are accurate.

Description

technical field [0001] The invention relates to the technical field of testing fluid flow laws in porous media, in particular to a testing system and method for nonlinear seepage characteristics of fluid in low-permeability porous media. Background technique [0002] Due to the complex pore structure and strong solid-liquid interaction in low-permeability porous media, the fluid inside it no longer obeys the classic Darcy's law during low-speed flow, but presents nonlinear seepage characteristics. figure 1 It is a schematic diagram of a typical non-linear seepage curve of a fluid in a low-permeability porous medium, which exhibits two obvious features, namely: there is a start-up pressure gradient (point A) and a nonlinear seepage section (section AD). For the study of these two characteristics, the most commonly used method is the steady-state method, that is, the "pressure difference-flow method". The quasi-linear section (DE section) measured by this method is relatively ...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N15/08
Inventor 杨正明熊生春刘学伟张亚蒲何英王学武齐亚东
Owner PETROCHINA CO LTD
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap