CN202814845U - Computed tomography (CT) scan-based three-phase relative permeability test system - Google Patents

Abstract

The utility model provides a computed tomography (CT) scan-based three-phase relative permeability test system. The CT scan-based three-phase relative permeability test system comprises a CT scanner, a core holding unit, a confining pressure system, an injection system and a back pressure control system, wherein the injection system comprises an oil injection system, a water injection system and a gas injection system which are respectively connected with an inlet end of the core holding unit; an inlet pressure gauge is arranged at an inlet of the core holding unit, and an outlet pressure gauge is arranged at an outlet of the core holding unit; a confining pressure interface of the core holding unit is connected with the confining pressure system; and an outlet end of the core holding unit is connected with the back pressure control system. By the CT scan-based three-phase relative permeability test system, the whole process of three-phase displacement is subjected to CT scan, the pressures at the inlet and the outlet are acquired in the whole process, and the whole-process fluid saturation data are acquired; and the CT scan-based three-phase relative permeability test system has intuitive and accurate results, and is simple in structure and convenient to operate.

Description

Three-phase relative permeability test macro based on CT scan

Technical field

The utility model relates to a kind of rock core reservoir physical simulation test unit, is specifically related to a kind of three-phase relative permeability test macro based on CT scan.

Background technology

The recent innovation of field of petroleum exploitation makes the research of three-phase relative permeability cause people's concern, under mining conditions such as carbon dioxide injection, combustion (of oil) in site, steam flood, injecting glue bundle and notes nitrogen, the dynamic in detail engineering calculation of oil reservoir needs the three-phase relative permeability data.

Mathematical model method is adopted in the calculating of the at present relative infiltration of three-phase more, namely according to the data of two-phase relative permeability, calculates three-phase relative permeability by Stone probability model I or II.The method is simple fast, but can only calculate a kind of data of saturated course, and limiting factor is many, and the degree of agreement of actual result is not fine.Adopt the method test three-phase relative permeability of laboratory physical simulation, the recovery process under the energy real simulation reservoir condition, data result is more accurately and reliably.

Utilize laboratory physical Modeling Method test three-phase relative permeability curve, crucial technology is the accurate measurement of three-phase saturation.Method commonly used comprises volumetric method at present, microwave weight method etc., but because the restriction of all factors, the test process complexity is loaded down with trivial details, and test result is very inaccurate, and these all directly have influence on the test result of three-phase relative permeability curve.

The CT scan technology has obtained widely research aspect reservoir physics, comprise that the nonuniformity of core description, rock core is measured, the core sample handling procedure is determined, the aspects such as the measurement of crack quantitative test, online saturation degree, flowing experiment research.For the test of three-phase fluid saturation degree, can adopt the dual energy scanning technique accurate measurement based on CT.Namely the CT scan rock core can obtain under the E1 energy:

CT _E1dry=(1-Φ)CT _E1grain+ΦCT _E1g （1）

CT _E1waterwet=(1-Φ)CT _E1grain+ΦCT _E1w （2）

CT _E1＝(1-Φ)CT _E1grain+Φ(S _gCT _E1g+S _wCT _E1w+S _oCT _E1o)（3）

Wherein,

CT _E1dryThe CT value of dried rock core under the-E1 energy;

CT _E1grainThe CT value of rock skeleton under the-E1 energy;

CT _E1waterwetThe rock CT value of complete saturation water under the-E1 energy;

CT _E1The CT value of certain moment rock core under the-E1 energy;

CT _E1gThe CT value of gas under the-E1 energy;

CT _E1wThe CT value of water under the-E1 energy;

CT _E1oThe CT value of oil under the-E1 energy;

The factor of porosity of Φ-rock;

S _gThe saturation degree of-gas;

S _w-water saturation degree;

S _oThe saturation degree of-oil.

The CT scan rock core can obtain under the E2 energy:

CT _E2dry=(1-Φ)CT _E2grain+ΦCT _E2g （4）

CT _E2waterwet=(1-Φ)CT _E2grain+ΦCT _E2w （5）

CT _E2＝(1-Φ)CT _E2grain+Φ(S _gCT _E2g+S _wCT _E2w+S _oCT _E2o)（6）

Wherein,

CT _E2dryThe CT value of dried rock core under the-E2 energy;

CT _E2grainThe CT value of rock skeleton under the-E2 energy;

CT _E2waterwetThe rock CT value of complete saturation water under the-E2 energy;

CT _E2The CT value of certain moment rock core under the-E2 energy;

CT _E2gThe CT value of gas under the-E2 energy;

CT _E2wThe CT value of water under the-E2 energy;

CT _E2oThe CT value of oil under the-E2 energy;

In addition,

S _g+S _w+S _o=1（7）

According to formula (1)～(7), the computing formula that can calculate the three-phase fluid saturation degree is:

$S_w=\frac{\left|\begin{array}{ccc}\left[\frac{({\mathrm{<figure-callout\; id="1"\; label="CT\; E"\; filenames="HDA00001974255100011.png"\; state="\{\{state\}\}">CT</figure-callout>}}_E-C{T}_{E1})({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1w})}{({\mathrm{<figure-callout\; id="1"\; label="CT\; E"\; filenames="HDA00001974255100011.png"\; state="\{\{state\}\}">CT</figure-callout>}}_E-{\mathrm{<figure-callout\; id="1"\; label="CT\; E"\; filenames="HDA00001974255100011.png"\; state="\{\{state\}\}">CT</figure-callout>}}_E)}\right]& ({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1o})& 0\\ \left[\frac{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2})({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})}{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2\mathrm{waterwet}})}\right]& ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2o})& 0\\ 1& 1& 1\end{array}\right|}{\left|\begin{array}{ccc}({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1w})& ({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1o})& 0\\ ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})& ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2o})& 0\\ 1& 1& 1\end{array}\right|}$

$S_o=\frac{\left|\begin{array}{ccc}({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1w})& \left[\frac{({\mathrm{<figure-callout\; id="1"\; label="CT\; E"\; filenames="HDA00001974255100011.png"\; state="\{\{state\}\}">CT</figure-callout>}}_E-{\mathrm{CT}}_{E1})({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1w})}{({\mathrm{CT}}_{\mathrm{<figure-callout\; id="1"\; label="E"\; filenames="HDA00001974255100011.png"\; state="\{\{state\}\}">E</figure-callout>}1\mathrm{dry}}-{\mathrm{<figure-callout\; id="1"\; label="CT\; E"\; filenames="HDA00001974255100011.png"\; state="\{\{state\}\}">CT</figure-callout>}}_E)}\right]& 0\\ ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})& \left[\frac{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2})({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})}{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2\mathrm{waterwet}})}\right]& 0\\ 1& 1& 1\end{array}\right|}{\left|\begin{array}{ccc}({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1w})& ({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1o})& 0\\ ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})& ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2o})& 0\\ 1& 1& 1\end{array}\right|}$

$S_g=\frac{\left|\begin{array}{ccc}({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1w})& ({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1o})& \left[\frac{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2})({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})}{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2\mathrm{waterwet}})}\right]\\ ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})& ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2o})& \left[\frac{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2})({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})}{({\mathrm{CT}}_{E2\mathrm{dry}}-{\mathrm{CT}}_{E2\mathrm{waterwet}})}\right]\\ 1& 1& 1\end{array}\right|}{\left|\begin{array}{ccc}({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1w})& ({\mathrm{CT}}_{E1g}-{\mathrm{CT}}_{E1o})& 0\\ ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2w})& ({\mathrm{CT}}_{E2g}-{\mathrm{CT}}_{E2o})& 0\\ 1& 1& 1\end{array}\right|}---\left(8\right)$

Use the CT dual energy scanning technique, measure dried rock core under two kinds of energy of E1, E2, rock core skeleton, saturation water rock core and certain CT value constantly, and the CT value of the identical energy therapeutic method to keep the adverse qi flowing downward, water, oil, but both application of formula (8) drew three-phase saturation and the permeability of a certain moment rock core.

Yet, not yet there is a complete test macro to finish measurement and the collection of above-mentioned data at present, therefore, need a kind of three-phase relative permeability test macro based on CT scan of exploitation badly.

The utility model content

For the above-mentioned problems in the prior art, the utility model provides a kind of three-phase relative permeability test macro based on CT scan.

For realizing the purpose of this utility model, the utility model comprises following technical scheme:

A kind of three-phase relative permeability test macro based on CT scan, it comprises: CT scanner, core holding unit, confined pressure system, injected system and back pressure control system;

This injected system comprises injection system, waterflood system and the gas injection system that is connected with the core holding unit inlet end respectively;

These core holding unit 6 porch inlet porting tensimeters 7, its exit arranges delivery gauge 4;

The confined pressure interface of core holding unit 6 connects this confined pressure system;

The endpiece of core holding unit 6 connects the back pressure control system.

Aforesaid system, wherein, this core holding unit is the core holding unit that is applied to CT scan, is made by the material that does not shield X ray, preferably, it is polyether-ether-ketone resin (PEEK) material core holding unit, the highest withstand voltage 30MPa, 150 ° of C of high-temperature resistant.

Aforesaid system, wherein, this injection system can comprise oil pump 8 and oil vessel 9.

Aforesaid system, wherein, this waterflood system can comprise water pump 16 and tank 17.

Aforesaid system, wherein, this gas injection system can comprise water storage device 15, gas injection pump 14 and middle air container 13.

Aforesaid system, preferably, these core holding unit 6 inlet ends are communicated with respectively injection system, waterflood system and gas injection system by three-position four-way valve.

Aforesaid system, wherein, this confined pressure system can comprise confined pressure liquid container 11 and confined pressure pump 12.

Aforesaid system, wherein, this back pressure control system can comprise backpressure pump 3 and check valve 2, core holding unit 6 endpiece are communicated with respectively backpressure pump 3 and go out oral fluid collection container 10 by check valve 2.

The beneficial effects of the utility model are that this test macro carries out CT scan to three-phase displacement overall process, and overall process gathers import and export pressure, obtains omnidistance saturated with fluid degrees of data, visual result, accurate, simple in structure, convenient operation.

Description of drawings

Fig. 1 is that embodiment 1 is based on the structural representation of the three-phase relative permeability test macro of CT scan.

Embodiment

Embodiment 1: based on the three-phase relative permeability test macro of CT scan.

Please refer to Fig. 1, the test macro of a kind of preferred implementation of the present utility model comprises CT scanner 1, core holding unit 6, confined pressure system, injected system and back pressure control system.Core holding unit 6 is made by polyether-ether-ketone resin (PEEK) material, the highest withstand voltage 30MPa, 150 ° of C of high-temperature resistant.Core holding unit 6 porch inlet porting tensimeters 7, the exit arranges delivery gauge 4.Core holding unit 6 inlet ends connect injected system, and injected system is comprised of injection system, waterflood system and gas injection system.Injection system comprises oil pump 8 and oil vessel 9, and waterflood system comprises water pump 16 and tank 17, and gas injection system comprises water storage device 15, gas injection pump 14 and middle air container 13.Core holding unit 6 inlet ends are communicated with respectively the gas outlet of oil pump 8 output terminals, water pump 16 output terminals and middle air container 13 by three-position four-way valve.The confined pressure interface of core holding unit 6 connects this confined pressure system, and the confined pressure system is by confined pressure liquid container 11 and confined pressure pump 12.The endpiece of core holding unit 6 connects the back pressure control system, and the back pressure control system comprises backpressure pump 3 and check valve 2, and core holding unit 6 endpiece are communicated with respectively backpressure pump 3 and go out oral fluid collection container 10 by check valve 2.Core holding unit 6 in-built tamping are tested rock core 5.Core holding unit 6 is fixed on the support with moving track, can prolong track and enter CT scanner 1 inside and finish CT scan.

Embodiment 2: use the device of embodiment 1 to carry out the three-phase relative permeability test experiments.Concrete steps are as follows:

1) during rock core is packed core holding unit into, adds confined pressure;

2) respectively dried core sample is scanned under two kinds of scanning voltages, writing scan position and the condition of scanning obtain the CT value of dried rock core under two kinds of energy;

3) rock core 100% is found time, behind the saturated brine, with step 2) under identical two kinds of scanning voltages, the condition of scanning and the scanning positions, rock core is scanned, obtain under two kinds of energy the fully rock core CT value of saturated brine;

4) in the displacement test process, with step 2) under identical two kinds of scanning voltages, the condition of scanning and the scanning positions, rock core is scanned, obtain the CT value of rock core under this moment two kinds of energy;

5) with step 2) under identical two kinds of scanning voltages to air, experiment with salt solution, experiment with oily and test usefulness gas and scan, obtain the CT value of this medium under two kinds of energy;

6) calculate the three-phase fluid saturation degree according to formula (8).

It will be appreciated by those skilled in the art that accompanying drawing is the synoptic diagram of a preferred embodiment, the utility model is not limited to this.

It will be appreciated by those skilled in the art that each parts among the embodiment can be distributed in the device of embodiment according to the embodiment description, also can carry out respective change and be arranged in the one or more devices that are different from present embodiment.Above-mentioned the utility model embodiment sequence number does not represent the quality of embodiment just to description.

Used specific embodiment in the utility model principle of the present utility model and embodiment are set forth, the explanation of above embodiment just is used for helping to understand method of the present utility model and core concept thereof; Simultaneously, for one of ordinary skill in the art, according to thought of the present utility model, all will change in specific embodiments and applications, in sum, this description should not be construed as restriction of the present utility model.

Claims (8)

1. the three-phase relative permeability test macro based on CT scan is characterized in that, described three-phase relative permeability test macro based on CT scan comprises: CT scanner, core holding unit, confined pressure system, injected system and back pressure control system;

Described injected system comprises injection system, waterflood system and the gas injection system that is connected with core holding unit (6) inlet end respectively;

Described core holding unit (6) porch inlet porting tensimeter (7), its exit arrange delivery gauge (4);

The confined pressure interface of core holding unit (6) connects described confined pressure system;

The endpiece of core holding unit (6) connects the back pressure control system.

2. the three-phase relative permeability test macro based on CT scan as claimed in claim 1 is characterized in that, described core holding unit is PEEK material core holding unit, the highest withstand voltage 30MPa, 150 ° of C of high-temperature resistant.

3. the three-phase relative permeability test macro based on CT scan as claimed in claim 1 is characterized in that, described injection system comprises oil pump (8) and oil vessel (9).

4. the three-phase relative permeability test macro based on CT scan as claimed in claim 1 is characterized in that, described waterflood system comprises water pump (16) and tank (17).

5. the three-phase relative permeability test macro based on CT scan as claimed in claim 1 is characterized in that, described gas injection system comprises water storage device (15), gas injection pump (14) and middle air container (13).

6. the three-phase relative permeability test macro based on CT scan as claimed in claim 1 is characterized in that, described core holding unit (6) inlet end is communicated with respectively injection system, waterflood system and gas injection system by three-position four-way valve.

7. the three-phase relative permeability test macro based on CT scan as claimed in claim 1 is characterized in that, described confined pressure system comprises confined pressure liquid container (11) and confined pressure pump (12).

8. the three-phase relative permeability test macro based on CT scan as claimed in claim 1, it is characterized in that, described back pressure control system comprises backpressure pump (3) and check valve (2), and check valve (2) connects respectively backpressure pump (3), core holding unit (6) endpiece and goes out oral fluid collection container (10).

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