CN209821028U - A rock core permeability testing device - Google Patents

Abstract

The utility model discloses a rock core permeability testing device, which relates to the technical field of petroleum engineering, and comprises a raw material system, a rock core holder, a back pressure valve and a gas measurement system connected in sequence. The two ends of the meter are connected. The gas measurement system includes a gas chamber and a gas composition analyzer. The gas chamber is connected to the outlet of the back pressure valve. The gas composition analyzer is located on the side wall of the gas chamber. There is also a filter screen at the outlet of the holder. The gas flow measurement of the utility model is not affected by temperature and pressure, and the measurement is simple and accurate, which improves the test accuracy of the device. The particles transported out of the core can prevent the back pressure valve from jamming and prolong the service life of the equipment.

Description

A rock core permeability testing device

technical field

The utility model relates to the technical field of petroleum engineering, in particular to a rock core permeability testing device.

Background technique

In the process of exploration and development of oil and gas fields, accurate measurement of permeability is the geological basis for oil and gas resource evaluation and development plan design, so its accurate calibration has important practical significance. Moreover, since liquid is used as a medium to test permeability, it will be affected by many factors, such as clay swelling with water, rock pore surface absorbing liquid, etc. These factors will affect the accuracy of permeability measurement. In view of the above problems, a method and technology for measuring permeability using gas as the test medium has been established. The constant pressure method is a common method, which tests the seepage flow rate of the rock sample by constant pressure at both ends of the rock sample. The key lies in the seepage volume. However, due to the limitation of the core structure and the size of the core in the experiment, the flow rate of the displaced gas during the entire experiment is extremely small, and it is difficult for the current commercially available flowmeters to accurately measure such a small flow rate; There are pressure and temperature changes that affect its volume, and the volume measured by the drainage method is not accurate.

Utility model content

In view of the above technical problems, the purpose of this utility model is to provide a rock core permeability testing device, which mainly improves the gas flow measurement system, so that the flow measurement is simple and accurate.

The utility model adopts the following technical solutions as follows:

A rock core permeability test device, including a raw material system, a core holder, a back pressure valve and a gas measurement system connected in sequence, a confining pressure pump is connected to the side of the core holder, and a rock sample is clamped in the core holder The outlet and inlet of the core holder are respectively connected to the two ends of the differential pressure gauge. The differential pressure gauge is used to measure the differential pressure at the inlet and outlet of the rock sample. A pressure gauge is installed at the outlet of the core holder. The gas measurement system includes a gas chamber and gas components Analyzer, the gas chamber is connected to the outlet of the back pressure valve, the gas composition analyzer is located on the side wall of the gas chamber, the probe is facing the inside of the gas chamber, and is used to measure the gas composition in the gas chamber; the outlet of the core holder is also provided with a filter, because Fluid flow will lead to the migration of particles in the rock. In order to prevent the gas from carrying particles from jamming the back pressure valve, this filter is installed.

Preferably, the raw gas system includes a raw gas cylinder and a piston container, the non-driving end of the piston container is respectively connected to the raw material bottle and the inlet of the core holder for pressurizing the raw gas, the driving end of the piston container is connected to the constant pressure Pump connection.

Preferably, the outlet or inlet of the core holder is connected with a vacuum device for evacuating the core holder system and auxiliary pipelines.

Preferably, the filter screen is located between the low-pressure introduction port of the differential pressure gauge and the back pressure valve, so that the differential pressure of the filter screen will not affect the differential pressure measurement of the core inlet and outlet.

The gas flow measurement principle of this device: fill the gas chamber with a certain known volume of reference gas (this gas is different from the raw material gas used in the experiment) before the test, test the gas content in the gas chamber, and measure at any time after the test starts For the gas content, since the volume of the reference gas is constant during the experiment, the volume of gas flowing into the gas chamber at this time can be calculated through the change of its proportion. Of course, by specifying the measurement time interval, the interval time can be obtained. Gas chamber gas increment, calculate the gas flow. For example: at the beginning, inject the reference gas volume V1 into the gas chamber, measure its content W1, calculate the total volume of gas in the gas chamber, V(0)=V1/W1; after time T, measure the reference gas content W2 , it can be calculated that the total volume of gas at this time V(T)=V1/W2, then the newly increased volume V(increase)=V(T)-V(0)=V1/W2-V1/W1

Compared with the prior art, the beneficial effects of the utility model are:

The gas flow measurement is not affected by temperature and pressure, and the measurement is simple and accurate, which improves the test accuracy of the device. At the same time, a filter is installed in front of the back pressure valve to intercept the particles moved out of the core and prevent the back pressure valve from Jamming, prolonging the service life of the equipment.

Description of drawings

Fig. 1 is the overall schematic diagram of the utility model;

In the figure, 1. Raw gas cylinder; 2. Piston container; 3. Core holder; 4. Constant pressure pump;

5. Confining pressure pump; 6. Rock sample; 7. Differential pressure gauge; 8. Pressure gauge; 9. Filter screen; 10. Back pressure valve;

11. Vacuum pump; 12. Gas chamber; 13. Gas component analyzer.

Detailed ways

Below, the utility model will be further described in conjunction with the accompanying drawings and specific implementation methods. It should be noted that, on the premise of not conflicting, the various embodiments or technical features described below can be combined arbitrarily to form new implementations. example.

Example:

A rock core permeability testing device, including a raw material system, a core holder 3 and a gas measurement system, the raw gas system includes a raw gas cylinder 1, a piston container 2, the non-driving end of the piston container 1 is connected to the raw material bottle 1 and the core holder respectively The inlet of the holder 3 is used to pressurize the raw material gas, and the driving end of the piston container 1 is connected with the constant pressure pump 4.

A confining pressure pump 5 is connected to the side of the core holder 3, and the rock sample 6 is clamped in the core holder 3. The differential pressure at the inlet and outlet of the rock sample 6 is measured, and the outlet of the core holder 3 is connected with a pressure gauge 8, a filter screen 9 and a back pressure valve 10 in sequence, and a vacuum pump 11 is also connected between the back pressure valve and the filter screen 9.

The gas measurement system includes a gas chamber 12 and a gas composition analyzer 13. The gas chamber 12 is connected to the outlet of the back pressure valve 10, and the gas chamber 12 is connected with a feed pipe for injecting a reference gas into the gas chamber for gas composition analysis. The instrument 13 is located on the peripheral side of the gas chamber 12 , and its probe is facing the inside of the gas chamber 12 for analyzing gas components in the gas chamber 12 .

In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "upper", "lower", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the utility model and Simplified descriptions do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and thus should not be construed as limiting the invention.

For those skilled in the art, various other corresponding changes and deformations can be made according to the technical solutions and ideas described above, and all these changes and deformations should fall within the protection scope of the claims of the present utility model.

Claims (4)

1. A rock core permeability testing device, comprising a raw material system, a rock core holder, a back pressure valve and a gas measurement system connected in sequence, the outlet and inlet of the rock core holder are respectively connected to the two ends of the differential pressure gauge, and the rock core is held A pressure gauge is also provided at the outlet of the device, and it is characterized in that the gas measurement system includes a gas chamber and a gas composition analyzer, the gas chamber is connected to the outlet of the back pressure valve, and the gas composition analyzer is located on the side wall of the gas chamber , the probe is facing the inside of the gas chamber; the outlet of the core holder is also provided with a filter. 2. a kind of rock core permeability testing device according to claim 1, is characterized in that, described raw material system comprises raw material gas bottle, piston container, and the non-drive end of piston container is connected with raw material bottle and rock core holder inlet respectively , the driving end of the piston container is connected with a constant pressure pump. 3. A rock core permeability testing device according to claim 1, characterized in that, the outlet or inlet of the rock core holder is connected with a vacuum pump. 4 . A rock core permeability testing device according to claim 1 , wherein the filter screen is located between the low pressure introduction port of the differential pressure gauge and the back pressure valve. 5 .