CN109917105B - Condensate gas non-equilibrium continuous failure testing method considering pressure reduction speed influence - Google Patents
Condensate gas non-equilibrium continuous failure testing method considering pressure reduction speed influence Download PDFInfo
- Publication number
- CN109917105B CN109917105B CN201910195279.6A CN201910195279A CN109917105B CN 109917105 B CN109917105 B CN 109917105B CN 201910195279 A CN201910195279 A CN 201910195279A CN 109917105 B CN109917105 B CN 109917105B
- Authority
- CN
- China
- Prior art keywords
- pressure
- gas
- condensate
- pump
- pvt cylinder
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Testing Resistance To Weather, Investigating Materials By Mechanical Methods (AREA)
Abstract
The invention discloses a condensate gas non-equilibrium continuous failure testing method considering the influence of a depressurization speed, which comprises the following steps of: (1) transferring a condensate gas sample into the PVT cylinder under the formation temperature and pressure; (2) building pressure to the formation pressure at two ends of a back pressure valve at a condensate gas sample discharge port; (3) replacing nitrogen in the dead volume of the pipeline and the back pressure valve by using condensate gas in the PVT cylinder; (4) reducing the PVT cylinder pressure to a dew point pressure; (5) reducing the pressure of a back pressure valve, separating out reverse condensate in the PVT cylinder, and separating flash oil and flash gas from the condensate gas discharged by the back pressure valve in an ice water bath; (6) continuously reducing the pressure until the pressure of the PVT cylinder is less than or equal to the waste pressure set by the gas reservoir; (7) and obtaining the cumulative recovery ratio of oil and gas and a relation curve of the saturation of the reverse condensate and the pressure during the non-equilibrium failure period. The method can simulate failure exploitation of condensate gas at different pressure drop speeds, and has important significance for researching non-equilibrium phenomenon in the condensate gas reservoir failure exploitation process.
Description
Technical Field
The invention relates to a non-equilibrium continuous failure testing method of condensate gas at a constant pressure drop speed in the process of condensate gas reservoir exploration and development.
Background
For the development of the condensate gas reservoir, the phase state research always runs through the exploration and development process of the condensate gas reservoir, and the phase state evaluation of the condensate gas has important significance for guiding the next exploration and development of the condensate gas reservoir, the well testing of the condensate gas well, the design of a development scheme, the numerical simulation research of the gas well, the evaluation of the gas reservoir reserves and the like. According to the industrial standard GB/T26981-: flash separation, well fluid composition test, dew point test, constant mass expansion, constant volume failure, separation experiment and the like.
The constant volume failure experiment about the condensate gas in the standard is carried out under the condition of phase equilibrium, but in the actual condensate gas reservoir development process, the gas reservoir phase state cannot be instantaneously balanced, so that some components in the gas reservoir cannot reach the phase equilibrium and are exploited (Liu Mian autumn, Su Lei, Zhou Jianfeng, and the like). The non-equilibrium phenomenon in the condensate gas reservoir development process is very common, and has obvious influence on the development effect, particularly the pressure gradient in the near wellbore area is large, so that the influence is more obvious (Weidong super, Liyongjie, Yao Lin, high-temperature and high-pressure non-equilibrium effect research of a water-gas-rich condensate gas system [ J ]. Chongqing academy of science and technology (Nature science edition), 2013,15 (3)). Therefore, it is urgently needed to establish a rapid and effective condensate gas reservoir non-equilibrium failure test method.
Disclosure of Invention
The invention aims to provide a condensate gas non-equilibrium continuous failure testing method considering the influence of a depressurization speed, which has reliable principle and simple and convenient operation, can effectively and accurately test the condensate liquid saturation and the oil gas recovery ratio in the non-equilibrium constant volume failure process of condensate gas at a constant depressurization speed, and predicts the phase state characteristics of the condensate gas during non-equilibrium failure exploitation.
In order to achieve the above technical objects, the present invention provides the following technical solutions.
A condensate gas non-equilibrium continuous exhaustion testing method considering the influence of depressurization speed is completed by a non-equilibrium continuous exhaustion testing device, the device consists of a pump I, a PVT cylinder, a back pressure valve, a nitrogen source, a pump II, a gas-liquid separator, a gas meter, a nitrogen intermediate container, a condensate gas intermediate container, a pump III and a thermostat, the lower end of the PVT cylinder is connected with the pump I, the upper end of the PVT cylinder is connected with the back pressure valve, the nitrogen source and the pump II, the nitrogen intermediate container and the condensate gas intermediate container are connected with the pump III, the back pressure valve is connected with the gas-liquid separator and the gas meter which are arranged in an ice water bath, the nitrogen intermediate container and the condensate gas intermediate container are both arranged in the thermostat, and a stirrer and a piston are also arranged in the PVT cylinder of the thermostat, and the method sequentially comprises the following steps:
(1) transferring a condensate gas sample of the volume 2/5 of the PVT cylinder into the PVT cylinder through a third pump and a condensate gas intermediate container under the formation temperature and pressure, starting a stirrer to stir until the sample is in a single-phase state, and standing for more than 4 hours;
(2) building pressure at two ends of the back pressure valve to the formation pressure through a second pump, a nitrogen source, a third pump and a nitrogen intermediate container;
(3) setting the first pump and the second pump as a constant pressure mode, wherein the constant pressure is the formation pressure, and replacing nitrogen in dead volumes of a pipeline and a back pressure valve by using condensate gas in a PVT cylinder under the formation pressure;
(4) reducing the pressure of the PVT cylinder to the dew point pressure by a first pump, standing for 1h, reading the height of a piston, and calculating the volume of the condensate gas in the PVT cylinder to be the constant volume Vc;
(5) setting a second pump as dew point pressure, then reducing the pressure of the second pump by a second back pressure valve, separating out a reverse condensate at the moment, finely adjusting the first pump to keep a piston unmovable in the pressure reduction process, keeping the condensate volume Vc all the time, and separating flash oil and flash gas from the condensate gas discharged from an outlet of the back pressure valve in an ice water bath;
(6) continuously reducing the pressure according to the pressure reduction speed required by the experiment, reading the height of the reverse condensation liquid level in the PVT cylinder at different pressure points so as to calculate the volume of the reverse condensation liquid, collecting flash oil through a separator, and collecting flash gas through a gas meter until the pressure of the PVT cylinder is less than or equal to the waste pressure set by a gas reservoir;
(7) utilizing the flash oil and the flash gas collected at each stage of pressure in the depressurization process to obtain the cumulative recovery ratio of the oil and the gas; and (4) obtaining the retrograde condensate saturation of each stage of pressure by using the constant volume Vc calculated in the step (4) and the retrograde condensate volume calculated in the step (6), thereby obtaining the cumulative recovery ratio of oil and gas and a relation curve of the retrograde condensate saturation and the pressure during non-equilibrium failure.
The invention installs a back pressure valve at the condensate gas sample discharge port to realize continuous pressure reduction and control of different pressure reduction speeds.
The separator provided by the invention is additionally provided with the ice water bath, so that the inaccuracy of the oil-gas ratio caused by insufficient separation of the sample is avoided.
And (5) standing the oil sample separated from each stage of pressure in ice water for more than 30min, and then weighing, metering and testing the oil gas chromatography.
In the step (5), the volume of the silicon oil can expand in the pressure reduction process, and the pump I is finely adjusted to enable the volume of the condensate gas in the PVT cylinder to be Vc all the time.
In the step (6), when the pressure of the PVT cylinder is reduced to a set pressure point, a new gas-liquid separator is immediately replaced, and the pump is not stopped in the whole process.
Compared with the prior art, the invention has the following beneficial effects:
compared with the traditional constant volume failure experiment, the constant volume failure exploitation in the continuous depressurization mode can realize the constant volume in the true sense and is more fit with the actual condensate gas reservoir exploitation characteristics.
Drawings
Fig. 1 is a schematic structural diagram of a condensate gas reservoir nonequilibrium continuous depletion test device.
In the figure:
1-pump one; 2, pumping a second pump; 3-9-valves; 10. 27-a thermostat; 11-PVT cartridge; 12-a back pressure valve; 13-ice water bath; 14-a gas-liquid separator; 15-gas meter; a 16-nitrogen gas source; 17-a stirrer; 18-23-valve; 24-pump three; 25-nitrogen intermediate vessel; 26-a condensate intermediate vessel; 28-piston.
Figure 2 is a plot of the retrograde condensate level versus piston position along a diametric cross-section during non-equilibrium depletion.
FIG. 3 is a plot of cumulative oil and gas recovery and retrograde condensate saturation versus pressure during non-equilibrium depletion for example 1.
Detailed Description
The invention is further illustrated below with reference to the figures and examples.
Example 1
In the example, the formation pressure of the condensate gas sample is 55MPa, the formation temperature is 137.8 ℃, the dew point pressure is 50.67MPa, and the gas-liquid ratio is 1561m3/m3And the required pressure drop speed in the non-equilibrium constant volume failure experiment is 5 MPa/h.
A condensate gas non-equilibrium continuous exhaustion testing method considering the pressure reduction speed influence is completed by a non-equilibrium continuous exhaustion testing device (shown in figure 1), the device comprises a pump I1, a PVT cylinder 11, a back pressure valve 12, a nitrogen source 16, a pump II 2, a gas-liquid separator 14, a gas meter 15, a nitrogen intermediate container 25, a condensate gas intermediate container 26 and a pump III 24, the lower end of the PVT cylinder 11 is connected with the pump I1, the upper end of the PVT cylinder is connected with the back pressure valve 12, the nitrogen source 16 and the pump II 2, the nitrogen intermediate container 25 and the condensate gas intermediate container 26 are also connected with the pump III 24, the back pressure valve is connected with the gas-liquid separator 14 and the gas meter 15 which are arranged in an ice water bath 13, the nitrogen intermediate container 25 and the condensate gas intermediate container 26 are both arranged in a constant temperature box 27, a stirrer 17 and a piston 28 are arranged in the PVT cylinder 11 of the constant temperature box 10, and the method sequentially comprises the following steps:
the method comprises the following steps: opening valves 3, 4, 5, 18, 19, 22 and 23, transferring a condensate gas sample with about 2/5 of the volume of the PVT cylinder into the PVT cylinder through the valve 18 at the formation temperature (137.8 ℃) and the pressure (55MPa), closing the valves 19 and 22 after transferring the sample, starting a stirrer to stir and balance until the sample is in a single-phase state (the reverse condensate disappears), and then standing for more than 4 hours;
step two: closing the valve 5, opening the valves 6, 7, 8, 9, 20 and 21, building pressure to the formation pressure through a second pump and a third pump, and closing the valves 18, 20, 21 and 23 after building pressure;
step three: setting the first pump and the second pump to be in a constant pressure mode (formation pressure (55MPa)), opening the valve 5, and replacing nitrogen in a pipeline between the valve 6 and the valve 18 and a dead volume of a back pressure valve by using condensate gas in a PVT cylinder under the formation pressure;
step four: the first control pump reduces the pressure of the PVT cylinder to the dew point pressure (50.67MPa), stands for 1h, reads the height of the piston, and calculates the volume of a condensate gas sample (the sample is in a single-phase gas state at this time) in the PVT cylinder through the height of the piston to obtain the constant volume Vc;
step five: setting the second pump as a dew point pressure (50.67MPa), depressurizing the second pump through the second pump by a back pressure valve according to a pressure reduction speed (5MPa/h) required by an experiment, separating a reverse condensate from the PVT cylinder, keeping a valve 3-9 open in the depressurization process, finely adjusting the first pump to keep a piston unmovable, keeping the sample volume Vc all the time, and separating the condensate gas discharged from an outlet of the back pressure valve in the depressurization process in an ice-water bath (wherein flash oil is collected in a gas-liquid separator 14, and flash gas is collected in a gas meter 15);
step six: continuously reducing the pressure, reading the height of a retrograde condensate liquid level in the PVT cylinder when the pressure of the PVT cylinder is reduced to a set pressure point, calculating the volume of the retrograde condensate liquid according to the height of the retrograde condensate liquid level, weighing, metering, testing an oil gas chromatogram and the like of flash oil and flash gas separated during each pressure interval until the pressure of the PVT cylinder is less than or equal to the waste pressure set by a gas reservoir;
step seven: calculating the cumulative recovery ratio of oil and gas by using the flash oil and the flash gas collected under each stage of pressure in the fifth step; and (3) calculating the retrograde condensate saturation of each stage of pressure by using the constant volume Vc calculated in the fourth step and the retrograde condensate volume calculated in the sixth step, so as to obtain the cumulative recovery ratio of oil and gas in the non-equilibrium failure period and a relation curve of the retrograde condensate saturation and the pressure (see figure 3).
In the fourth step and the sixth step, the condensate gas is condensed under the dew point pressure to a constant volume VcAnd volume V of retrograde condensatefCalculated according to the following formula (see fig. 2):
wherein:
Vfis the volume of the reverse condensate, ml;
h is the vertical distance between the anti-condensation liquid level and the bottom of the piston frustum, and is cm;
theta is an acute angle formed by the lower bottom and two waists of the cross section (in an isosceles trapezoid shape) of the piston frustum;
r2the radius of the bottom of the piston frustum is cm;
h2is part of a piston frustumVertical height, cm;
V0is the dead volume, ml, caused by the piston frustum part;
Vcthe volume of the sample at the dew point pressure is the constant volume (ml);
hois the piston height before sample transfer (also known as the counter reference), cm;
h1height of piston cm after sample transfer and standing for 1 h.
Claims (2)
1. A condensate gas non-equilibrium continuous failure testing method considering the influence of depressurization speed is completed by a non-equilibrium continuous failure testing device which consists of a pump I (1), a PVT cylinder (11), a back pressure valve (12), a nitrogen source (16), a pump II (2), a gas-liquid separator (14), a gas meter (15), a nitrogen intermediate container (25), a condensate gas intermediate container (26) and a pump III (24), wherein the lower end of the PVT cylinder (11) is connected with the pump I (1), the upper end of the PVT cylinder is sequentially connected with the back pressure valve (12), the nitrogen source (16) and the pump II (2), and is also respectively connected with the pump III (24) through the nitrogen intermediate container (25) and the condensate gas intermediate container (26), the back pressure valve is sequentially connected with the gas-liquid separator (14) and the gas meter (15) which are arranged in an ice water bath (13), and the nitrogen intermediate container, the condensate gas intermediate container and the PVT cylinder are all arranged in a constant temperature box, the PVT cylinder is internally provided with a stirrer (17) and a piston (28), and the method sequentially comprises the following steps:
(1) transferring a condensate gas sample of the volume 2/5 of the PVT cylinder into the PVT cylinder through a third pump and a condensate gas intermediate container under the formation temperature and pressure, starting a stirrer to stir until the sample is in a single-phase state, and standing for more than 4 hours;
(2) building pressure at two ends of the back pressure valve to the formation pressure through a second pump, a nitrogen source, a third pump and a nitrogen intermediate container;
(3) setting the first pump and the second pump as a constant pressure mode, wherein the constant pressure is the formation pressure, and replacing nitrogen in dead volumes of a pipeline and a back pressure valve by using condensate gas in a PVT cylinder under the formation pressure;
(4) the pressure of the PVT cylinder is reduced to the dew point pressure through the first pump, the PVT cylinder is kept stand for 1h, then the height of the piston is read, the condensate gas volume in the PVT cylinder is calculated, and the condensate gas volume is the constant volume Vc, and the Vc is calculated according to the following formula:
wherein:
r2the radius of the bottom of the piston frustum is cm;
V0is the dead volume, ml, caused by the piston frustum part;
hothe height of the piston before sample transferring is cm;
h1transferring the sample and standing for 1h to obtain the height of the piston, cm;
(5) setting a second pump as dew point pressure, then reducing the pressure of the second pump by a second back pressure valve, separating out a reverse condensate at the moment, finely adjusting the first pump to keep a piston unmovable in the pressure reduction process, keeping the condensate volume Vc all the time, and separating flash oil and flash gas from the condensate gas discharged from an outlet of the back pressure valve in an ice water bath;
(6) continuously reducing pressure according to the pressure drop speed required by an experiment, reading the height of the reverse condensate liquid level in the PVT cylinder at different pressure points, thereby calculating the volume of the reverse condensate liquid, immediately replacing a new gas-liquid separator when the pressure of the PVT cylinder is reduced to a set pressure point, collecting flash oil through the separator without stopping a pump in the whole process, collecting flash gas through a gas meter until the pressure of the PVT cylinder is less than or equal to the waste pressure set by a gas reservoir, and collecting the volume V of the reverse condensate liquid until the pressure of the PVT cylinder is less than or equal to the waste pressure set by the gasfCalculated according to the following formula:
wherein:
h is the vertical distance between the anti-condensation liquid level and the bottom of the piston frustum, and is cm;
theta is an acute angle formed by the lower bottom and two waists of the cross section of the piston frustum;
r2the radius of the bottom of the piston frustum is cm;
h2is the vertical height of the piston frustum part, cm;
V0is the dead volume, ml, caused by the piston frustum part;
(7) utilizing the flash oil and the flash gas collected at each stage of pressure in the depressurization process to obtain the cumulative recovery ratio of the oil and the gas; and (4) obtaining the retrograde condensate saturation of each stage of pressure by using the constant volume Vc calculated in the step (4) and the retrograde condensate volume calculated in the step (6), thereby obtaining the cumulative recovery ratio of oil and gas and a relation curve of the retrograde condensate saturation and the pressure during non-equilibrium failure.
2. The condensate gas non-equilibrium continuous depletion test method considering the effect of depressurization rate according to claim 1, wherein in the step (5), the flash oil separated at each stage of pressure is left standing in ice water for more than 30min, and then weighed, metered and tested for oil gas chromatography.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910195279.6A CN109917105B (en) | 2019-03-14 | 2019-03-14 | Condensate gas non-equilibrium continuous failure testing method considering pressure reduction speed influence |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910195279.6A CN109917105B (en) | 2019-03-14 | 2019-03-14 | Condensate gas non-equilibrium continuous failure testing method considering pressure reduction speed influence |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN109917105A CN109917105A (en) | 2019-06-21 |
| CN109917105B true CN109917105B (en) | 2020-07-31 |
Family
ID=66964968
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910195279.6A Active CN109917105B (en) | 2019-03-14 | 2019-03-14 | Condensate gas non-equilibrium continuous failure testing method considering pressure reduction speed influence |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN109917105B (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117688272B (en) * | 2023-12-08 | 2024-06-21 | 西南石油大学 | Condensate recovery ratio calculation method for unbalanced mist reverse condensate |
Family Cites Families (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1971273A (en) * | 2006-12-12 | 2007-05-30 | 中国石油天然气股份有限公司 | Condensate gas reservoir fluid constant volume depletion test method |
| CN102841192B (en) * | 2012-09-25 | 2014-10-29 | 成都理工大学 | Desorption analysis experimental facility of coal rock |
| CN103645126B (en) * | 2013-12-02 | 2015-09-30 | 西南石油大学 | Stratum high-temperature high-pressure air-water phase percolation curve assay method |
| CN103912700B (en) * | 2014-04-18 | 2016-05-25 | 西南石油大学 | A kind of high pressure high temperature experiment back-pressure valve |
| CN104502552B (en) * | 2015-01-22 | 2016-04-06 | 中国石油大学(华东) | A kind of High Temperature High Pressure foam static filtration instrument and application thereof |
| CN105239973B (en) * | 2015-10-28 | 2024-03-01 | 中国石油化工股份有限公司 | Condensate gas reservoir blocking removal physical simulation experiment device and experiment method thereof |
| CN205352904U (en) * | 2015-12-29 | 2016-06-29 | 西南石油大学 | It becomes interior rock stress sensitivity test of pressure device to decide confined pressure |
| CN105547961B (en) * | 2016-01-05 | 2018-02-16 | 西南石油大学 | Retrograde gas condensate saturation degree determines method in exhaustion formula exploitation sandstone gas condensate reservoir reservoir |
| CN106501300A (en) * | 2016-10-09 | 2017-03-15 | 中国石油天然气股份有限公司 | Method for testing nonequilibrium phase transition of high-water-content dense condensate gas reservoir |
| CN106596371B (en) * | 2016-12-12 | 2018-11-30 | 西南石油大学 | Saturation conditions condensate gas reservoir failure formula develops nearly wellblock retrograde condensation damage experiment evaluation method |
| CN108318666A (en) * | 2018-04-29 | 2018-07-24 | 江苏拓创科研仪器有限公司 | The more PROCESS COUPLING experimental rigs of rock, gas of Unconventional gas |
-
2019
- 2019-03-14 CN CN201910195279.6A patent/CN109917105B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN109917105A (en) | 2019-06-21 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101967970B (en) | Method for measuring dynamic capillary pressure of core under conditions of reservoir temperature and pressure | |
| CN105203705B (en) | A kind of heavy component deposition causes the method for testing of reservoir damage | |
| CN110907334A (en) | Device and method for measuring radial flow oil-water relative permeability of conglomerate full-diameter core | |
| CN109596457B (en) | Pipe flow evaluation method of foaming agent for drainage and gas production | |
| CN103278418A (en) | Determination device and method of constraint irreducible water saturation in reservoir rock core | |
| CN102121891A (en) | Device and method for testing molecular diffusion coefficients in multi-component oil-gas system under high temperature and high pressure | |
| CN104775809B (en) | Water-soluble gas reservoir development simulation experiment system and method | |
| CN103940715B (en) | The natural percolation ability analogue experiment method of rock | |
| CN109932272B (en) | CO (carbon monoxide) 2 Displacement experiment system and displacement experiment method | |
| CN202562823U (en) | Compressible fluid high-temperature high-pressure density test system | |
| CN108131121B (en) | Oil-water-gas output control and metering device and method in thickened oil recovery experiment | |
| CN112285201B (en) | Method for testing gas injection, reverse evaporation and condensate oil saturation of low-permeability condensate gas reservoir | |
| CN106290786A (en) | A kind of heavy crude heat extraction rock core displacement test device and experiment pressure reduction antihunt means thereof | |
| CN106950149A (en) | A kind of experimental provision and method for measuring overflow gas solubility | |
| CN107202815A (en) | Continuous flow type high-temperature high-pressure experimental device | |
| CN109917105B (en) | Condensate gas non-equilibrium continuous failure testing method considering pressure reduction speed influence | |
| CN201443388U (en) | Device for continuously and automatically metering output of oil well | |
| CN112378812A (en) | Experimental device and method for determining desorption rate of adsorption type shale gas | |
| RU155020U1 (en) | INSTALLATION FOR MEASURING THE DEBIT OF OIL WELL PRODUCTS | |
| CN108843315B (en) | Sensing type comprehensive automatic metering device and oil quality calculation method | |
| CN109752507A (en) | A kind of rock core displacement test oil-gas-water metering device | |
| CN110886596B (en) | Experimental device and method for simulating carbon dioxide to improve thick oil flowing capacity | |
| RU2468203C1 (en) | Simulation method of formation-fluid system of developed deposit | |
| CN114295775B (en) | Experimental method for representing rheological property of foam fluid in pipe flow state | |
| CN109441435A (en) | A kind of indoor experimental apparatus and method of the variation of level monitoring gas well gas liquid two-phase temperature in wellbore |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |