Quantitative evaluation device and method for imbibition oil and gas production capacity of shale under reservoir conditions

Abstract

The invention relates to a quantitative evaluation device and method for shale imbibition oil and gas production capacity under reservoir conditions, the quantitative evaluation device for shale imbibition oil and gas production capacity under reservoir conditions comprises a saturated imbibition chamber, a visual measuring tube and a water drainage and gas collection device, and a detachable steel sealing cover is arranged at the bottom of the saturated imbibition chamber; a shale core is placed on an imbibition net of the saturated imbibition chamber, the saturated imbibition chamber, the live oil intermediate container, the imbibition agent intermediate container and the visual measuring tube are arranged in the constant-temperature box, and the live oil intermediate container and the imbibition agent intermediate container are connected between the constant-pressure constant-speed pump and an inlet of a steel sealing cover of the saturated imbibition chamber in parallel. A steel sealing cover of the saturated imbibition chamber is connected with an emptying valve and a vacuum pump; an overflow pipe is arranged on the arc-shaped top of the saturated imbibition chamber; the overflow pipe is connected with a four-way valve, and the four-way valve is further connected with a visual measuring tube and a drainage and gas collection device; and the visual measuring tube is positioned right above the saturated imbibition chamber. The problems of liquid leakage of the imbibition chamber and fragmentation of the metering glass tube are effectively solved, and the reservoir imbibition process is truly reflected.

Description

Technical field:

[0001] The present invention relates to the technical field of shale oil development, and in particular to a device and method for quantitatively evaluating the oil and gas production capacity of shale under reservoir conditions. Background technology:

[0002] With the increasing depletion of conventional oil and gas resources and the country's increasing demand for energy, the main direction of domestic research and development has begun to move towards shale resources. Shale reservoirs are characterized by low porosity and ultra-low permeability, and are generally developed by horizontal well volume fracturing. The imbibition effect causes the oil and gas in the shale matrix to be replaced by water into the cracks, thereby increasing the shale oil recovery rate. The shale imbibition process is simulated under reservoir conditions in the laboratory, and its oil and gas production capacity is quantitatively evaluated, which is of great significance for guiding the on-site fracturing construction parameters and drainage system.

[0003] At present, the commonly used imbibition experimental methods include mass method and volume method. The mass method evaluates the imbibition effect by hanging the core on a precision balance and measuring the mass change of the core before and after imbibition to obtain the imbibition rate and imbibition amount; the volume method evaluates the imbibition effect by directly measuring the volume of the output liquid, and determines the output and output rate of the liquid through tools such as a measuring cylinder. The existing technologies (CN201710006804, CN201811482680, CN201910359161, CN111521542A, CN202221906639, CN202210519102) have designed high-temperature and high-pressure visual imbibition devices that can simulate the imbibition environment under formation conditions. However, these methods only involve measuring the amount of oil produced by imbibition, while the real formation is a state of oil and gas mixing. Since the gas production of shale oil layers is not measured, it is impossible to reflect the real mining situation to a certain extent. At the same time, in the devices of these methods, a measuring glass tube made of high temperature and high pressure resistant sapphire glass is used, and the equipment is complex and expensive. In addition, the prior art (CN202221906639) places the Amott bottle containing the core and resistant to high temperature and high pressure on a rotating table, and reduces the error caused by the inability to observe the oil droplets by centrifugal force, but the centrifugal force will affect the experimental results, and there are certain limitations; the measuring glass tube of the prior art (CN202210519102) is directly connected to the imbibition chamber, which is prone to fragmentation caused by pressure changes, increasing the experimental risk and safety hazards.

[0004] The existing technologies (CN201710833425, CN201910681469, CN201911375069, CN202010325398, CN202311634613) combine the imbibition device with other technologies. While studying the imbibition amount and the imbibition rate, the imbibition process can be monitored from various angles. However, these technologies cannot place the equipment under high temperature and high pressure conditions, cannot accurately simulate the formation environment, the devices are complex and expensive, and there is no calculation of the gas production by imbibition of shale oil reservoirs, which also has limitations. Summary of the invention:

[0005] One object of the present invention is to provide a quantitative evaluation device for shale oil and gas production capacity under reservoir conditions, which is used to solve the problems of lack of gas production capacity evaluation method for shale oil reservoirs, easy leakage of the imbibition chamber and breakage of the glass tube, complicated steps, and expensive equipment in the prior art; another object of the present invention is to provide a method for quantitatively evaluating the shale oil and gas production capacity under reservoir conditions using the quantitative evaluation device.

[0006] The technical solution adopted by the present invention to solve its technical problems is: the quantitative evaluation device for shale imbibition oil and gas production capacity under reservoir conditions comprises a saturated imbibition chamber, a live oil intermediate container, an imbibition agent intermediate container, a visual measuring tube, a thermostat, a constant temperature control device, a constant speed and pressure pump, a vacuum pump, a hand pump and a drainage and gas collection device, a detachable steel sealing cover is arranged at the bottom of the saturated imbibition chamber, a shale core is placed on the imbibition net of the saturated imbibition chamber, the saturated imbibition chamber, the live oil intermediate container, the imbibition agent intermediate container and the visual measuring tube are arranged in the thermostat, the live oil intermediate container and the imbibition agent intermediate container are connected in parallel between the constant pressure and speed pump and the steel sealing cover inlet of the saturated imbibition chamber, the steel sealing cover of the saturated imbibition chamber is connected to the drain valve and the vacuum pump through a pipeline, a pressure gauge is arranged in the saturated imbibition chamber, and the saturated An overflow pipe is arranged at the arc-shaped top of the imbibition chamber; the overflow pipe is connected to one port of the four-way valve; the second port of the four-way valve is connected to the back-pressure valve, the ninth valve, the back-pressure valve pressure gauge, and the hand pump in sequence through the second switch and pipeline arranged at the port; the back-pressure valve outlet has an eighth valve; the third port of the four-way valve is connected to the sixth valve, the visual measuring tube, the tenth valve, and the drainage and gas collecting device in sequence through the pipeline; the fourth port of the four-way valve is arranged with an emptying switch; the visual measuring tube is located directly above the saturated imbibition chamber, and the drainage and gas collecting device is located above the side of the visual measuring tube; the drainage and gas collecting device consists of a drainage trough, a gas collecting measuring tube, and a U-shaped connecting pipe; the U-shaped connecting pipe is located in the drainage trough, one end of the U-shaped connecting pipe is connected to the tenth valve, and the other end of the U-shaped connecting pipe extends into the gas collecting measuring tube, and the lower middle part of the gas collecting measuring tube is located in the drainage trough.

[0007] In the above scheme, a first valve is arranged at the inlet of the live oil intermediate container, and a third valve is arranged at the outlet; a second valve is arranged at the inlet of the imbibing agent intermediate container, and a fourth valve is arranged at the outlet.

[0008] In the above scheme, the drain valve and the fifth valve are connected in parallel to the steel sealing cover of the saturated imbibition chamber.

[0009] The method for quantitatively evaluating the shale oil and gas production capacity under the above reservoir conditions using the quantitative evaluation device comprises the following steps:

[0010] Step 1: Preparation of live oil: according to the gas-oil ratio of the wellhead at the oil field, natural gas is pressed into the degassed crude oil on the ground to prepare simulated oil;

[0011] Step 2: Shale core preparation and pretreatment;

[0012] Step 3: Calculate the liquid compression under formation temperature and pressure: Use a vacuum pump to evacuate the saturated imbibition chamber, and adjust the temperature of the thermostat to the reservoir temperature; Set the pressure of the constant speed and constant pressure pump to the reservoir pressure, and inject live oil into the saturated imbibition chamber in a constant pressure mode until the flow rate of the constant speed and constant pressure pump is 0, and record the change in the reading during the injection process of the constant speed and constant pressure pump as ΔV1;

[0013] Step 4: Drain the residual oil: adjust the pressure of the saturated imbibition chamber to atmospheric pressure, and slowly open the drain switch above the saturated imbibition chamber and the drain valve below it until all the residual oil in the chamber is drained;

[0014] Step 5, preparation before saturation and imbibition: open the steel sealing cover at the bottom of the saturated imbibition chamber, place the shale core on the imbibition net support, close the steel sealing cover, start the vacuum pump, and evacuate the saturated imbibition chamber and the shale core for 48 hours;

[0015] Step 6: Saturate the core with live oil: Set the pressure of the constant speed and constant pressure pump to the reservoir pressure, and inject live oil into the saturated imbibition chamber in constant pressure mode until the flow rate of the constant speed and constant pressure pump is 0; keep the constant speed and constant pressure pump open, and saturate the core with live oil for 10 days under the conditions of reservoir temperature and pressure; after the core is saturated, record the change in the reading during the injection process of the constant speed and constant pressure pump as ΔV2; calculate the core volume V according to formula (1): c , calculate the saturated oil volume ΔV according to formula (2) pore , according to formula (3) to calculate the saturated oil porosity

[0016]

[0017] ΔV por e=V c -(ΔV1-ΔV2) (Formula 2)

[0018]

[0019] Where: L is the core length, D is the core diameter;

[0020] Step 7, shale imbibition oil and gas production simulation experiment under reservoir conditions: use a hand pump to set the back pressure valve pressure slightly lower than the reservoir pressure; set the pressure of the constant speed constant pressure pump to the reservoir pressure, quickly inject imbibition agent into the saturated imbibition chamber to replace the live oil therein, open the valve connecting the saturated imbibition chamber and the back pressure valve until the imbibition agent continuously flows out from the outlet of the back pressure valve, close the valve connecting the saturated imbibition chamber and the back pressure valve, at this time, the imbibition agent has completely filled the saturated imbibition chamber and the pipeline connected to the visual metering tube at its upper part, and start the high temperature and high pressure imbibition experiment of the shale core;

[0021] Step 8: During the high-temperature and high-pressure imbibition process, the pressure of the constant-speed constant-pressure pump is always maintained at the reservoir pressure. At regular intervals, the valve connected to the visual metering tube is slowly opened. Under the action of buoyancy, the oil and gas produced by imbibition during this period are discharged from the saturated imbibition chamber through the pipeline. When the imbibition agent flows out continuously, the valve is closed; the produced oil enters the visual metering tube, and the imbibition oil production in different time periods is recorded by reading the readings in the visual metering tube; the produced gas enters the drainage and gas collecting device along the pipeline, and the imbibition gas production in different time periods is recorded by reading the readings in the drainage and gas collecting device; T1, T2…T n The oil and gas output in the time period are recorded as V o1 and V g1 、V o2 and V g2 …V on and V gn ; No. T i The amount of gas produced by imbibition during the time period is T i With T i-1 The difference between the readings of the drainage gas collection device in the time period and the readings of the visual tube are subtracted; when the readings of the imbibition oil and gas output no longer increase, the imbibition ends, and the final imbibition oil output V is recorded. o , the gas output is V g ; Combining formula (4) and formula (5) to get T i Imbibition oil production rate per unit volume of shale core in a time period τ oi and gas production rate τ gi According to formulas (6) and (7), the imbibition oil production capacity of unit volume of shale core under reservoir conditions is evaluated as follows: o and gas production capacity η g :

[0022]

[0023] Where i = 1, 2…n; V oi T iOil output in a time period; V gi T i Gas output within a time period;

[0024]

[0025] Step nine, replace different imbibition media, different temperatures and pressures, and repeat steps one to eight to obtain the effects of different factors on shale imbibition oil and gas production.

[0026] The specific method of step 2 in the above scheme is as follows: a standard plug-like core with a length of 5 cm and a diameter of 2.5 cm is drilled from a full-size shale core in parallel to the bedding direction. The core is cylindrical and dried to a constant weight at the reservoir temperature. The true length L and true diameter D of the core column are accurately measured using a vernier caliper.

[0027] Beneficial effects:

[0028] 1. The present invention uses real shale cores drilled along the direction parallel to the bedding. In the shale oil saturation process and the simulation process of imbibition oil and gas production, the temperature and pressure are set according to the actual shale reservoir conditions, so as to restore the real imbibition development environment of the reservoir to the greatest extent; different imbibition media, different temperatures and pressures can be used in the experimental process, so as to obtain the influence of different factors on the shale imbibition oil and gas production effect.

[0029] 2. The quantitative evaluation method of the present invention has a simple process, high precision (0.01 ml), does not require high-temperature and high-pressure resistant visual glass made of sapphire, has low equipment cost, and the visual measuring tube is arranged outside the saturated imbibition chamber, which effectively solves the problems of leakage in the imbibition chamber and breakage of the measuring glass tube due to uneven temperature and pressure, avoids safety accidents, can simulate the temperature, pressure and rock properties of the reservoir, truly reflect the reservoir imbibition process, and provide reliable support for shale oil development plans.

[0030] 3. The present invention can solve the problem of lack of gas production capacity evaluation method when exploiting shale oil. Since the saturation and imbibition processes are carried out under high temperature and high pressure conditions, the relationship between the output oil and gas output over time can be observed in real time. Description of the drawings:

[0031] Figure 1 This is a schematic diagram of the structure of a device for quantitatively evaluating the oil and gas production capacity of shale under reservoir conditions provided by the present invention.

[0032] In the figure: 1-1 the first valve, 1-2 the second valve, 1-3 the third valve, 1-4 the fourth valve, 1-5 the fifth valve, 1-6 the sixth valve, 1-7 the drain valve, 1-8 the eighth valve, 1-9 the ninth valve, 1-10 the tenth valve, 2-1 the live oil intermediate container, 2-2 the imbibition agent intermediate container, 3-1 the drain switch, 3-2 the second switch, 4-saturated imbibition chamber, 5-shale core, 6-visible measuring tube, 7-imbibition net, 8-steel sealing cover, 9-1 the saturated imbibition chamber pressure gauge, 9-2 the back pressure valve pressure gauge, 10-vacuum pump, 11-back pressure valve, 12-hand pump, 13-constant temperature box, 14-constant speed and constant pressure pump, 15-drainage and gas collecting device, 16-constant temperature control equipment. Specific implementation method:

[0033] The present invention will be further described below:

[0034] See also Figure 1 The quantitative evaluation device for shale imbibition oil and gas production capacity under the reservoir condition comprises a saturated imbibition chamber, a live oil intermediate container, an imbibition agent intermediate container, a visual measuring tube, a thermostat, a constant temperature control device, a constant speed and pressure pump, a vacuum pump, a hand pump and a drainage and gas collecting device. A detachable steel sealing cover is arranged at the bottom of the saturated imbibition chamber, a shale core is placed on the imbibition net of the saturated imbibition chamber, the saturated imbibition chamber, the live oil intermediate container, the imbibition agent intermediate container and the visual measuring tube are arranged in the thermostat, the live oil intermediate container and the imbibition agent intermediate container are connected in parallel between the constant pressure and speed pump and the steel sealing cover inlet of the saturated imbibition chamber, a first valve is arranged at the inlet of the live oil intermediate container, and a third valve is arranged at the outlet; a second valve is arranged at the inlet of the imbibition agent intermediate container, and a fourth valve is arranged at the outlet. The steel sealing cover of the saturated imbibition chamber is connected to the drain valve and the vacuum pump through a pipeline, and the drain valve and the valve 5 are connected in parallel to the steel sealing cover of the saturated imbibition chamber; the saturated imbibition chamber is provided with a saturated imbibition chamber pressure gauge, and the arc-shaped top of the saturated imbibition chamber is provided with an overflow pipe; the overflow pipe is connected to one port of the four-way valve, and the second port of the four-way valve is connected to the back pressure valve, the ninth valve, the back pressure valve pressure gauge, and the hand pump in sequence through the second switch and pipeline provided at the port, and the back pressure valve outlet has an eighth valve; the third port of the four-way valve is connected to the sixth valve, the visual measuring tube, the tenth valve, and the drainage gas collecting device in sequence through a pipeline; the fourth port of the four-way valve is provided with a drain switch; the visual measuring tube is located directly above the saturated imbibition chamber, and the drainage gas collecting device is located above the side of the visual measuring tube. The drainage gas collecting device consists of a drainage trough, a gas collecting measuring tube, and a U-shaped connecting pipe, the U-shaped connecting pipe is located in the drainage trough, one end of the U-shaped connecting pipe is connected to the tenth valve, and the other end of the U-shaped connecting pipe extends into the gas collecting measuring tube, and the lower and middle part of the gas collecting measuring tube is located in the drainage trough.

[0035] The quantitative evaluation method of shale oil and gas production capacity quantitative evaluation device under the above reservoir conditions is combined with Figure 1This quantitative evaluation method for shale oil and gas production capacity under reservoir conditions uses a real shale core drilled along the bedding direction with a diameter of 2.5 cm, a constant temperature box and a saturated imbibition chamber to accurately evaluate the shale saturated oil porosity and imbibition oil and gas production capacity under reservoir conditions. Specifically, it includes the following steps:

[0036] Step 1: Preparation of live oil: According to the gas-oil ratio of the wellhead at the oil field site, natural gas was pressed into the degassed crude oil on the ground at a ratio of 48.8:1 at a reservoir pressure of 37 MPa and a temperature of 110°C to prepare simulated oil.

[0037] Step 2: Preparation and pretreatment of shale samples. A standard plug-like core with a length of about 5 cm and a diameter of about 2.5 cm was drilled from a full-size shale core parallel to the bedding direction. The core was cylindrical and dried at a reservoir temperature of 110°C to a constant weight. The length of the core column L = 5.024 cm and the diameter D = 2.494 cm were accurately measured using a vernier caliper.

[0038] Step three, calculate the liquid compression under formation temperature and pressure. Close the first valve 1-1, the first valve 1-2, the first valve 1-3, the first valve 1-4, the first valve 1-5, the first valve 1-6, the first valve 1-8, the first valve 1-9, and the first valve 1-10, open the drain valve 1-7, and use the vacuum pump to evacuate the saturated imbibition chamber to vacuum. Adjust the constant temperature control device 14 to adjust the temperature of the constant temperature box 13 to the reservoir temperature of 110°C. Close the drain valve 1-7, open the first valve 1-1 and the third valve 1-3, open the constant speed and constant pressure pump 14 and set the pressure to the reservoir pressure of 37MPa, and inject live oil into the saturated imbibition chamber 4 in constant pressure mode until the flow rate of the constant speed and constant pressure pump 14 is 0, and close the first valve 1-1 and the third valve 1-3. Record the change in the reading during the injection process of the constant speed and constant pressure pump as ΔV1=61.11ml.

[0039] Step 4: Drain the residual oil. Slowly open the drain switch 3-1 at the upper end of the four-way valve above the saturated imbibition chamber and the drain valve 1-7 at the lower end until all the residual oil in the saturated imbibition chamber is drained, and then close the drain valve 1-7 and drain switch 3-1.

[0040] Step 5, preparation before saturation and imbibition. Open the steel sealing cover 8 of the saturated imbibition chamber, put the shale core on the imbibition net 7 of the saturated imbibition chamber, and close the steel sealing cover 8. Open the drain valve 1-7, start the vacuum pump 10, and vacuum the saturated imbibition chamber and the shale core for 48 hours. After the vacuum treatment is completed, close the drain valve 1-7 and the vacuum pump 10.

[0041] Step 6: Saturate the core with live oil. Open the first valve 1-1 and the third valve 1-3, set the pressure of the constant speed and constant pressure pump 14 to the reservoir pressure of 37 MPa, and inject live oil into the saturated imbibition chamber 4 in constant pressure mode until the flow of the constant speed and constant pressure pump 14 is 0. Keep the constant speed and constant pressure pump 14 open, and saturate the core with live oil for 10 days under the conditions of reservoir temperature 110°C and pressure 37 MPa. After the core is saturated, record the change in the reading during the injection process of the constant speed and constant pressure pump 14 as ΔV2=38.89 ml, the first valve 1-1, the third valve 1-3. Calculate the volume V of the core according to formula (1): c =24.54cm 3 According to formula (2) and formula (3), the saturated oil volume ΔV is calculated respectively. pore =2.32ml and saturated oil porosity

[0042]

[0043] ΔV pore =V c -(ΔV1-ΔV2) (Formula 2)

[0044]

[0045] Step seven, simulation experiment of shale imbibition oil and gas production under reservoir conditions. Open the ninth valve 1-9, control the hand pump 12 to set the pressure of the back pressure valve 11 to 36.8MPa. Open the second valve 1-2, the fourth valve 1-4 and the second switch 3-2 at the lower end of the four-way valve, set the pressure of the constant speed constant pressure pump 14 to the reservoir pressure of 37MPa, quickly inject the imbibition agent into the saturated imbibition chamber 4 to replace the live oil therein, slowly open the eighth valve 1-8 until the outlet of the eighth valve 1-8 connected to the back pressure valve has imbibition agent continuously flowing out, close the eighth valve 1-8 and the second switch 3-2 at the lower end of the four-way valve. At this time, the imbibition agent has completely filled the saturated imbibition chamber 4 and the upper part of the pipeline connected to the sixth valve 1-6, and the shale core high temperature and high pressure imbibition experiment begins.

[0046] Step eight, during the high-temperature and high-pressure imbibition process, always maintain the pressure of the constant-speed constant-pressure pump 14 at the reservoir pressure of 37MPa. Slowly open the sixth valve 1-6 and the tenth valve 1-10 on the 1st, 2nd, 4th, 8th, 12th, 16th, 20th, 25th and 30th days respectively. Under the action of buoyancy, the oil and gas produced by imbibition during this time period are discharged from the saturated imbibition chamber 4 through the pipeline. When the imbibition agent flows out continuously, close the sixth valve 1-6. The produced oil enters the visual metering tube 6. By reading the reading in the visual metering tube 6, the amount of imbibition oil produced in different time periods can be recorded; the produced gas enters the drainage and gas collecting device 15 along the pipeline. By reading the reading in the drainage and gas collecting device 15, the amount of imbibition gas produced in different time periods can be recorded. T1, T2…Tn The oil and gas output in the time period are recorded as V o1 and V g1 、V o2 and V g2 …V on and V gn (See Table 1 for details). i The amount of gas produced by imbibition during the time period is T i With T i-1 The difference in readings of the drainage gas collection device 15 during the time period is subtracted from the difference in readings of the visual metering tube 6. When the readings of the imbibition oil and gas output no longer increase, the imbibition is considered to be over, and the final imbibition oil output V is recorded. o =0.72ml, the gas output is V g =36.6cm 3 Further combining formula (4) and formula (5) to obtain T i Imbibition oil production rate per unit volume of shale core in a time period τ oi and gas production rate τ gi (See Table 1 for details). According to formulas (6) and (7), the imbibition oil production capacity per unit volume of shale core under reservoir conditions is evaluated as follows: o =0.029ml / cm 3 and gas production capacity η g =1.49cm 3 / cm 3 .

[0047]

[0048] In the formula, i=1, 2…n.

[0049]

[0050] Table 1 Oil and gas production and oil and gas production rates in different time periods

[0051]

[0052] The present invention uses real shale cores drilled along the direction parallel to the bedding. During the shale oil saturation process and the simulation process of imbibition oil and gas production, the temperature and pressure are set according to the actual shale reservoir conditions, so as to restore the real imbibition development environment of the reservoir to the greatest extent. Different imbibition media, different temperatures and pressures can be used during the experiment, so as to obtain the influence of different factors on the shale imbibition oil and gas production effects.

Claims

1. A quantitative evaluation device for shale oil and gas production capacity under reservoir conditions, characterized by: The quantitative evaluation device for shale imbibition oil and gas production capacity under reservoir conditions comprises a saturated imbibition chamber, a live oil intermediate container, an imbibition agent intermediate container, a visual measuring tube, a thermostat, a thermostatic control device, a constant speed and pressure pump, a vacuum pump, a hand pump and a drainage and gas collecting device. A detachable steel sealing cover is arranged at the bottom of the saturated imbibition chamber, a shale core is placed on the imbibition net of the saturated imbibition chamber, the saturated imbibition chamber, the live oil intermediate container, the imbibition agent intermediate container and the visual measuring tube are arranged in the thermostat, the live oil intermediate container and the imbibition agent intermediate container are connected in parallel between the constant pressure and speed pump and the steel sealing cover inlet of the saturated imbibition chamber, the steel sealing cover of the saturated imbibition chamber is connected to a drain valve and a vacuum pump through a pipeline, a pressure gauge is arranged in the saturated imbibition chamber, and an overflow is arranged on the arc-shaped top of the saturated imbibition chamber. flow pipe; the overflow pipe is connected to one port of the four-way valve, the second port of the four-way valve is connected to the back pressure valve, the ninth valve, the back pressure valve pressure gauge, and the hand pump in sequence through the second switch and pipeline arranged at the port, and the back pressure valve outlet has an eighth valve; the third port of the four-way valve is connected to the sixth valve, the visual measuring tube, the tenth valve, and the drainage and gas collecting device in sequence through the pipeline; the fourth port of the four-way valve is provided with an emptying switch; the visual measuring tube is located directly above the saturated imbibition chamber, and the drainage and gas collecting device is located above the side of the visual measuring tube; the drainage and gas collecting device consists of a drainage trough, a gas collecting measuring tube, and a U-shaped connecting pipe, the U-shaped connecting pipe is located in the drainage trough, one end of the U-shaped connecting pipe is connected to the tenth valve, and the other end of the U-shaped connecting pipe extends into the gas collecting measuring tube, and the lower middle part of the gas collecting measuring tube is located in the drainage trough.

2. The device for quantitatively evaluating the oil and gas production capacity of shale under reservoir conditions according to claim 1, characterized in that: The inlet of the live oil intermediate container is provided with a first valve, and the outlet is provided with a third valve; the inlet of the imbibition agent intermediate container is provided with a second valve, and the outlet is provided with a fourth valve.

3. The device for quantitatively evaluating the oil and gas production capacity of shale under reservoir conditions according to claim 2, characterized in that: The drain valve and the fifth valve are connected in parallel to the steel sealing cover of the saturated imbibition chamber.

4. A method for quantitatively evaluating shale oil and gas production capacity under reservoir conditions using the device for quantitatively evaluating shale oil and gas production capacity under reservoir conditions according to claim 3, characterized in that The steps include: Step 1: Preparation of live oil: according to the gas-oil ratio of the wellhead at the oil field, natural gas is pressed into the degassed crude oil on the ground to prepare simulated oil; Step 2: Shale core preparation and pretreatment; Step 3: Calculate the liquid compression under formation temperature and pressure: Use a vacuum pump to evacuate the saturated imbibition chamber, and adjust the temperature of the thermostat to the reservoir temperature; Set the pressure of the constant speed and constant pressure pump to the reservoir pressure, and inject live oil into the saturated imbibition chamber in a constant pressure mode until the flow rate of the constant speed and constant pressure pump is 0, and record the change in the reading during the injection process of the constant speed and constant pressure pump as ΔV1; Step 4: Drain the residual oil: adjust the pressure of the saturated imbibition chamber to atmospheric pressure, and slowly open the drain switch above the saturated imbibition chamber and the drain valve below it until all the residual oil in the chamber is drained; Step 5, preparation before saturation and imbibition: open the steel sealing cover at the bottom of the saturated imbibition chamber, place the shale core on the imbibition net support, close the steel sealing cover, start the vacuum pump, and evacuate the saturated imbibition chamber and the shale core for 48 hours; Step 6: Saturate the core with live oil: Set the pressure of the constant speed and constant pressure pump to the reservoir pressure, and inject live oil into the saturated imbibition chamber in constant pressure mode until the flow rate of the constant speed and constant pressure pump is 0; keep the constant speed and constant pressure pump open, and saturate the core with live oil for 10 days under the conditions of reservoir temperature and pressure; after the core is saturated, record the change in the reading during the injection process of the constant speed and constant pressure pump as ΔV2; calculate the core volume V according to formula (1): c , the saturated oil volume ΔVpore is calculated according to formula (2), and the saturated oil porosity is calculated according to formula (3) φ o: Δ pore = -(ΔV - ΔV2) (Equation 2) Where: L is the core length, D is the core diameter; Step 7, shale imbibition oil and gas production simulation experiment under reservoir conditions: use a hand pump to set the back pressure valve pressure slightly lower than the reservoir pressure; set the pressure of the constant speed constant pressure pump to the reservoir pressure, quickly inject imbibition agent into the saturated imbibition chamber to replace the live oil therein, open the valve connecting the saturated imbibition chamber and the back pressure valve until the imbibition agent continuously flows out from the outlet of the back pressure valve, close the valve connecting the saturated imbibition chamber and the back pressure valve, at this time, the imbibition agent has completely filled the saturated imbibition chamber and the pipeline connected to the visual metering tube at its upper part, and start the high temperature and high pressure imbibition experiment of the shale core; Step 8: During the high-temperature and high-pressure imbibition process, the pressure of the constant-speed constant-pressure pump is always maintained at the reservoir pressure. At regular intervals, the valve connected to the visual metering tube is slowly opened. Under the action of buoyancy, the oil and gas produced by imbibition during this period are discharged from the saturated imbibition chamber through the pipeline. When the imbibition agent flows out continuously, the valve is closed; the produced oil enters the visual metering tube, and the imbibition oil production in different time periods is recorded by reading the readings in the visual metering tube; the produced gas enters the drainage and gas collecting device along the pipeline, and the imbibition gas production in different time periods is recorded by reading the readings in the drainage and gas collecting device; T1, T2…T n The oil and gas production in each time period are recorded as Vo1 and Vg1, Vo2 and Vg2, ... Von and Vgn respectively; the imbibition gas production in the Ti time period is T i With T i-1 The difference between the readings of the drainage gas collection device in the time period and the readings of the visual tube are subtracted; when the readings of the imbibition oil and gas output no longer increase, the imbibition ends, and the final imbibition oil output V is recorded. o , the gas output is V g ; Combining formula (4) and formula (5) to get T i Imbibition oil production rate per unit volume of shale core in a time period τ oi and gas production rate τ gi According to formulas (6) and (7), the imbibition oil production capacity of unit volume of shale core under reservoir conditions is evaluated as follows: o and gas production capacity η g : Where i = 1, 2…n; V oi T i Oil output in a time period; V gi T i Gas output within a time period; Step nine, replace different imbibition media, different temperatures and pressures, and repeat steps one to eight to obtain the effects of different factors on shale imbibition oil and gas production.

5. The method for quantitative evaluation using the quantitative evaluation device for shale oil and gas production capacity under reservoir conditions according to claim 4 is characterized in that: The specific method of step 2 is as follows: a standard plug-like core with a length of 5 cm and a diameter of 2.5 cm is drilled from a full-size shale core in parallel to the bedding direction. The core is cylindrical, and the core is dried to a constant weight at the reservoir temperature. The true length L and true diameter D of the core column are accurately measured using a vernier caliper.

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