RU166252U1 - DEVICE FOR DETERMINING PHASE PERMEABILITY - Google Patents

Abstract

A device for determining phase permeabilities, containing a core holder with a test sample installed in it in a rubber cuff, a thermostat that maintains a constant temperature in the test sample, plunger pumps for supplying working fluids (oil and water) to the test sample at reservoir pressure, a pump for creating a mining pressure, pipelines for supplying and discharging working fluids with valves, back pressure regulator, containers with working fluids, volumetric flask for measuring liquid level on the outlet of the core holder, pressure sensors, a differential pressure gauge for measuring the pressure drop across the test sample and a gas cylinder, characterized in that the device further comprises a pipeline with a valve installed therein and a gas flow meter connecting the gas cylinder to the core holder.

Description

The utility model relates to the field of studying the phase permeability of oil and gas reservoirs and can be used to solve a large number of geo-field problems.

Known devices for determining phase permeabilities in reservoir conditions (OST 39-235-89. Oil. Method for determining phase permeabilities in laboratory conditions with joint stationary filtration. - 35 s; Ivanov MK, Kalmykov GA, Belokhin BC and other Petrophysical methods for the study of core material. Textbook in 2 books. Book 2: Laboratory methods of petrophysical studies of core material. - Moscow: Publishing House of Moscow University, 2008. - 113 p .; Dobrynin V.M. ., Kovalev AG, Kuznetsov AM et al. Phase permeabilities of oil and gas reservoirs. - M .: V IOENG, 1982. - Survey information Ser. “Geology, geophysics and oil field development.” - 56 s; Instructions for use of an automated software-measuring complex for petrophysical core research PIK-OFP / EP-3. Novosibirsk: ZAO Geologika ", 2008. - 33 s; RU 108105, publ. 09/10/2011), which contain plunger pumps that supply oil and water to the sample at reservoir pressure, a core holder designed to be installed in the rubber cuff of the test sample, a pump for creating rock pressure pipelines for supply and discharge of working fluids with valves, containers with working fluids, back pressure regulator, volumetric flask for measuring the liquid level at the outlet of the core holder, a thermostat that maintains a constant temperature in the test sample, differential pressure gauge for measuring the pressure drop across the test sample. These devices allow two-phase filtration of liquids through a rock sample.

A disadvantage of the described devices is the inability to determine the phase permeability during three-phase filtration of oil, water and gas.

The objective of the proposed device is to increase its functionality.

The solution to this problem is achieved by the fact that, according to known devices, including a core holder with a test sample installed in it in a rubber cuff, a thermostat that maintains a constant temperature in the test sample, plunger pumps that supply oil and water to the sample at reservoir pressure, and a pump for creating rock pressure, pipelines for supplying and discharging working fluids with valves, back pressure regulator, containers with working fluids, volumetric flask for measuring liquid level bones at the outlet of the core holder, pressure sensors, a differential pressure gauge for measuring the pressure drop across the test sample and a gas cylinder, the proposed device further comprises a pipeline with a valve installed therein and a gas flow meter connecting the gas cylinder to the core holder.

The drawing shows a hydraulic diagram of the proposed device.

The device includes a core holder 1 with a test sample installed in it in a rubber cuff, a thermostat 2, which maintains a constant temperature in the test sample, plunger pumps 3 and 4, which supply oil and water, respectively, at reservoir pressure, a gas cylinder 5, and a pump for creating rock pressure 6, pipelines for supplying 7 and for extracting 8 working fluids with valves 9, containers with working fluids 10, back pressure regulator 11, volumetric flask for measuring the liquid level at the core exit erzhatelya 12, pressure sensors 13, the differential pressure gauge 14 for measuring the pressure drop across the test sample, the gas flow meter 15.

The device operates as follows.

Working fluids (water, oil) are supplied to the inlet of the core holder 1 by high pressure plunger pumps 3 and 4. Gas enters the inlet of the core holder 1 from the gas cylinder 5 under the action of pressure. Oil, water and gas are supplied to the inlet of the core holder 1 in various ratios, set for liquids with the established volumetric velocities of plunger pumps and for gas - by setting the required flow rate with a valve installed in the gas pipeline 7, while the flow rate is controlled using a gas flow meter 15 .

The direct experiment to determine the phase permeability includes a number of modes (experiments) during which oil, water and gas are supplied to the sample in various ratios. Filtration at each ratio is carried out until a stationary regime is established, which is determined by the equality of the injected and flowing volumes of liquids, the stability of the differential pressure and the immutability of the electrical resistance.

The phase ratio (water, oil, gas) varies from experience to experience, while the total flow rate of the phases remains constant.

Each pumping mode continues until steady steady-state filtration sets in, which is determined by the readings of differential pressure gauge 14 and electrical resistance measurements on the test sample, after which a new experiment begins with a different ratio of oil to water in the stream. The number of modes must be at least 5.

Test conditions should ensure the preservation or reproduction of the natural physicochemical characteristics of the rock system — formation fluids, and the maintenance of temperature and pressure values corresponding to the formation during the experiment. The velocity of the joint fluid flow during the test should be selected based on the values of the field velocities of displacement of the displacement front.

GOST 39-235-89 recommends conducting an experiment to determine phase permeabilities at a working pressure as close as possible to the reservoir pressure, while the working pressure should not be less than 10 times the pressure drop across the entire sample so as not to take into account the change in gas volume during flow through the sample.

Based on the measured pressure differential ratios for fixed ratios of water, oil and gas, the phase permeabilities are calculated using the Darcy equation:

,

,

where i is the mode (flow rate for water, oil and gas);

j is the phase (water, oil, gas);

Q - fluid flow rate, ml / s;

µ — fluid viscosity, MPa · s;

L is the length of the sample, m;

ΔP is the pressure difference across the sample (differential pressure), kPa;

F is the cross-sectional area of the sample, m ² .

Using the proposed device will determine the phase permeability during three-phase filtration of oil, water and gas.

Claims (1)

A device for determining phase permeabilities, containing a core holder with a test sample installed in it in a rubber cuff, a thermostat that maintains a constant temperature in the test sample, plunger pumps for supplying working fluids (oil and water) to the test sample at reservoir pressure, a pump for creating a mining pressure, pipelines for supplying and discharging working fluids with valves, back pressure regulator, containers with working fluids, volumetric flask for measuring liquid level on the outlet of the core holder, pressure sensors, a differential pressure gauge for measuring the pressure drop across the test sample and a gas cylinder, characterized in that the device further comprises a pipeline with a valve installed therein and a gas flow meter connecting the gas cylinder to the core holder.

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