CN103485753B - Oriented perforating steam flooding two-dimensional proportion physical simulation device and using method thereof - Google Patents

Abstract

The invention discloses a two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with bottom water and a use method thereof. The device includes an injection unit, a model body, a bottom water temperature control unit, a bottom water pressure control unit, a model heat preservation unit, a production There are 7 parts including measurement unit, data acquisition and image processing unit. The invention is used to explore the mechanism of steam flooding in bottom water reservoirs, understand the influence of bottom water in reservoirs on steam flooding, the temperature field development characteristics and production characteristics of steam flooding in heavy oil reservoirs with bottom water, and guide the production of heavy oil in bottom water. Tibetan steam flooding development.

Description

Two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoir with bottom water and its application method

technical field

The invention belongs to the field of geophysical exploration, and relates to numerical processing and simulation technology of physical exploration, in particular to a two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with bottom water and a method for using the same.

Background technique

A commonly used method in heavy oil recovery is steam injection thermal recovery, in which steam huff and puff is an important method in steam injection thermal recovery. Steam huff and puff is to continuously inject a certain amount of steam into a production well in a short period of time, shut down the well for several days, and then start the well for production. Due to the short steam injection time, quick effect and good economic benefits, steam huff and puff is often used as a mining method before steam flooding at home and abroad. Another method of thermal recovery with steam injection is steam flooding. Steam is injected into one or more wells to heat the viscous heavy oil underground to reduce its viscosity. Then, under the action of steam distillation, the crude oil is driven to adjacent production wells. Well production. Steam flooding is currently the most widely used thermal recovery technology. It overcomes the weakness of the limited heating radius of steam huff and puff to a certain extent, and can continuously provide heat to the formation. It is one of the effective methods to enhance oil recovery after steam huff and puff.

Most of the heavy oil in my country belongs to the marginal oil reservoirs of thermal recovery technology, which is very difficult to develop, mainly reflected in: the deep burial of oil layers (mainly 900m ~ 1400m), the high dryness of the bottom of the well cannot be guaranteed for steam injection; in addition, the edge and bottom water of the oil layer Active, reservoir huffing and depressurization are likely to cause water flooding, and the development effect is poor. In particular, at present, most of the heavy oil in my country has entered the late stage of steam huff and puff development, and is in the low-yield and low-efficiency stage. The impact of edge and bottom water is even greater, so it is urgent to change the development method.

Indoor proportional physical simulation research is one of the important contents of heavy oil steam injection thermal recovery reservoir engineering research. The ratio of length ratio, force ratio, velocity ratio, temperature difference ratio and concentration difference ratio between the ratio physical model and the oil field prototype has same value. Therefore, it can accurately reflect the dynamic characteristics of the oil production process and the sweep efficiency characteristics of the injected fluid in the entire reservoir or some (unit) reservoirs, and is widely used in mechanism research, optimization of well pattern configuration, indicators of injection-production parameters and technical policies To predict the effect of on-site implementation and provide a reliable basis for reservoir development plan design and on-site rational implementation. However, the existing steam flooding proportional physical simulation device for heavy oil reservoirs has the following shortcomings or deficiencies in the physical simulation experiment:

(1) There is no simulation unit for edge water, bottom water or edge-bottom water, so it is impossible to carry out physical simulation experiments of steam flooding in reservoirs with edge-bottom water. The influence of edge-bottom water on steam flooding Development of oil recovery technology for water reservoirs;

(2) The pressure of the low-pressure model is only 0.1 MPa, which is quite different from the conditions of steam flooding reservoirs, and cannot fully reflect the production characteristics of steam flooding in heavy oil reservoirs;

(3) The pressure of the high-pressure model can reach dozens of MPa, but the model must be placed in a hyperbaric chamber, the operation is complicated, and the test period is long, which limits the progress of physical simulation research and requires a lot of manpower and material resources.

In order to meet the needs of actual reservoir development, a geophysical exploration technology that can objectively reflect the actual situation of stratigraphic reservoirs is urgently needed.

Contents of the invention

In order to solve the above problems, the present invention provides a two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with bottom water and its application method.

According to the first technical solution of the present invention, a two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with bottom water includes an injection unit, a model body, a bottom water temperature control unit, a bottom water pressure control unit, a model heat preservation unit, an output 7 parts including metering unit, data acquisition and image processing unit;

The injection unit is used to inject the wet steam with adjustable injection speed, temperature and dryness into the model body. The injection speed ranges from ^20cm3 /min to ^100cm3 /min, the temperature ranges from 120℃ to 350℃, and the dryness ranges 20% to 80%; the model body is used to simulate the actual oil reservoir, the model body can be rotated 360° in the radial direction and 45° in the axial direction, and can simulate the formation dip angle at any angle; the bottom water temperature control unit is used to control the temperature of the bottom water body , with the functions of heating, cooling, and constant temperature; the bottom water pressure control unit is used to control the bottom water pressure of the bottom water body, the bottom water pressure reflects the energy of the bottom water body, and has the functions of constant pressure and pressure decrease;

The model insulation unit is used to raise the temperature of the model body and control the constant temperature to simulate the initial temperature condition of the reservoir, that is, the temperature before the reservoir is not exploited; the output measurement unit is used to simulate the pressure control of the production well, and the output fluid is cooled It is collected in a measuring cylinder to measure oil production and liquid production; it is used to analyze the production dynamic characteristics of steam injection oil production, that is, the relationship between oil production, liquid production, water content, oil-steam ratio, recovery degree and time; Among them, the oil-steam ratio is the ratio of how many tons of steam can be injected to extract one ton of crude oil when steam injection is used to develop the reservoir; the recovery degree is the percentage of the cumulative oil production to the original geological reserves during the development of a reservoir; data collection and The image processing unit is used to control the changes of bottom water pressure and injection-production pressure difference, monitor the temperature and pressure inside the model body, and generate temperature field and pressure field maps in real time on the computer to control the changes of bottom water pressure and injection-production pressure difference.

Specifically, the model body includes the model body shell, heat insulation layer, bottom water layer and edge water layer, front and rear cover plates, graphite pads, fastening bolts (sealing components), simulated injection wells, simulated production wells, temperature sensors, pressure sensors and temperature sensor interface and pressure sensor interface; the model body shell is a rectangular parallelepiped shell welded by stainless steel plates, and flanges and cover plates are respectively set on the front panel and rear panel of the rectangular parallelepiped shell; the cover plate on the front panel has no interface, the cover plate on the rear panel has interfaces for simulated injection wells, simulated production wells, thermocouples and pressure pipes; graphite pads are used between the cover plates on the front panel and the cover plate on the rear panel and the shell flange of the model body , sealed by fastening bolts; the inner side of the model body shell is surrounded by a heat insulation layer, and a heat-resistant inorganic adhesive is used to coat and bond oil-repellent and water-repellent heat insulation materials.

Preferably, the number of flanges respectively provided on the front panel and the rear panel of the cuboid housing is two.

Further, the edge water layer is located on the same side as the injection well of the model body, and the bottom water layer is located at the lower part of the model body.

Preferably, the edge water layer is located on the same side as the production well of the model body, and the bottom water layer is located at the lower part of the model body.

Preferably, the simulated injection well and the simulated production well are stainless steel pipes with a diameter of 6 mm. The above slots simulate the perforated well sections of injection wells and production wells on site, and the positions of the slots are determined after proportional modeling according to the perforated well sections of on-site injection wells and production wells. Arrange thermocouples and pressure measuring points in the oil layer (the horizontal distance between thermocouples and pressure measuring points is 5cm, and the longitudinal distance between thermocouples and pressure measuring points is 2.5cm. The part outside the edge water layer and bottom water layer inside the model body is "oil layer") , which is used to monitor the development of temperature field and pressure field in the steam flooding physical simulation test in real time.

There are 9 × 21 temperature sensors distributed inside the oil layer, and one branch is distributed in the bottom water layer, edge water layer or bottom water layer. 5×6 pressure sensors are distributed inside the oil layer, and 1 branch is distributed in the bottom water layer, edge water layer or bottom water layer.

Further, the injection unit includes a water source, a high-precision flow pump (flow accuracy not greater than 1.0%), and a steam generator with a controllable dryness. The inlet port of the steam generator with controllable dryness is connected to the inlet port of the simulated injection well of the model body; the steam outlet of the steam generator with controllable dryness is within 0.5 meters from the simulated injection well.

Preferably, the bottom water temperature control unit includes a heat exchanger, pipelines, and a circulating water bath, and the heat exchanger is located inside the bottom water layer (the edge water layer is located on one side of the model body, and the bottom water layer is located at the bottom of the model body) , the circulating water bath is located behind the model body, the outlet end of the circulating water bath is connected to the inlet section of the heat exchanger, the outlet end of the heat exchanger is connected to the inlet end of the circulating water bath, and the circulating water bath, heat exchanger, and pipeline form a loop to realize water circulation , used to control the temperature of the bottom water.

Preferably, the bottom water pressure control unit includes a pressure sensor, a buffer container, and a high-precision flow pump. The outlet end of the container is connected, the upper end of the buffer container is connected with the pressure gauge, and the inlet end of the buffer container is connected with the outlet end of the high-precision metering pump.

Preferably, the model heat preservation unit includes a temperature sensor, a heater, a heat preservation jacket, and a temperature controller. The heater is connected with the temperature controller.

Preferably, the output metering unit includes a cooler, a back pressure valve, a liquid collector (measuring cylinder), the outlet end of the production well is connected to the inlet end of the back pressure valve, the upper part of the back pressure valve is connected to a gas source, a pressure gauge, and the back pressure valve A graduated cylinder is placed below the outlet end of the lower section, and the graduated cylinder collects the produced fluid.

Preferably, the data acquisition and image processing unit includes hardware and software. The hardware includes a temperature sensor, a pressure sensor, a data acquisition module, and a microcomputer. The signal lines of the temperature sensor and the pressure sensor are connected to the data acquisition module, and the data acquisition module is connected to the microcomputer. .

According to the second technical solution of the present invention, a method for using a two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with bottom water is provided:

The first step is to establish a two-dimensional proportional physical model of steam flooding in heavy oil reservoirs with bottom water. Install simulated injection wells, simulated production wells, bottom water temperature control units, and bottom water pressure control units. The bottom water layer is located at the bottom of the model body, fill with oil layer sand, install the front cover of the model body, and tighten the bolts to seal;

The second step is process connection. The injection unit is connected to the simulated injection well of the model body, the output metering unit is connected to the simulated production well of the model body, and the pressure sensor, temperature sensor, and data acquisition module are connected to the microcomputer in turn. The simulated injection well is connected with the injection unit, and the simulated production well is connected with the metering unit;

The third step is to establish the initial temperature conditions of the reservoir. Start the model insulation unit, raise the temperature of the model body and control the constant temperature, and simulate the initial temperature conditions of the reservoir;

The fourth step is to simulate the saturated water of the oil layer and measure the pore volume of the oil layer;

The fifth step is to simulate saturated oil in the oil layer, start the bottom water pressure control unit, control the pressure of the bottom water, and obtain the initial oil saturation of the simulated oil layer and the initial pressure condition of the simulated oil layer;

The sixth step is steam injection for oil recovery. Wet steam is injected at a rate of (20-100cm ³ /min), at a temperature of (120-350°C) and at a dryness of (20-80%), and the output metering unit is used to collect the output fluid . Bottom water pressure control is carried out according to the change of oil field production pressure;

In the seventh step, the output fluid is separated. Measure oil output, water output, liquid output, oil-steam ratio, recovery degree;

The eighth step is to analyze the production dynamic characteristics of steam injection recovery. That is, the relationship curve law of oil production, liquid production, water cut, oil-steam ratio, recovery degree and time.

The two-dimensional proportional physical simulation device and application method for steam flooding of heavy oil reservoirs with bottom water according to the present invention are used to explore the mechanism of steam flooding in bottom water reservoirs, and to understand the effect of edge water, bottom water or bottom water on steam flooding in oil reservoirs Influence, temperature field development characteristics and production characteristics of steam flooding in edge water, bottom water or bottom water heavy oil reservoirs, guide the development of steam flooding in edge water, bottom water or bottom water heavy oil reservoirs. Compared with the prior art, the present invention has the following advantages:

(1) Physical simulation of steam flooding in heavy oil reservoirs with edge water, bottom water or bottom water;

(2) It can simulate five-point, seven-point, nine-point, row-column well pattern, vertical well-horizontal well combination, the model body can be rotated 360° radially and 45° axially, and can simulate formation dip.

(3) The thermal insulation structure of the model body and the thermal insulation structure of the injection-production well are original. Under the condition that the temperature is as high as 350°C, the simulation of heat and mass transfer from the oil layer to the cap and bottom layer is accurate.

(4) The physical simulation of steam huff and puff and steam drive linkage has been realized, and physical simulation experiments of layered steam injection, layered oil recovery, combined injection and separate production, and separate injection and combined production can be carried out at the same time.

(5) Bottom water pressure and temperature are controllable;

(6) The dryness of injected steam is controllable;

(7) Calculate and simulate the elastic energy of the reservoir based on the similarity theory, and objectively describe the dynamic characteristics of steam huff and puff, recovery degree and distribution characteristics of remaining oil.

Description of drawings

Fig. 1 is a schematic diagram of a two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with edge and bottom water according to the present invention;

Figure 2 is a schematic diagram of five-point well pattern layout;

Figure 3 is a schematic diagram of a seven-point well pattern;

Figure 4 is a schematic diagram of the layout of the nine-point well pattern;

Fig. 5 is a schematic diagram of row and column well pattern layout;

Fig. 6 is a schematic diagram of vertical well-horizontal well pattern layout;

Fig. 7 is a schematic diagram of the injection unit;

Fig. 8 is a schematic diagram of the model body;

Fig. 9 is a schematic diagram of the edge and bottom water temperature control unit;

Fig. 10 is a schematic diagram of the edge and bottom water pressure control unit;

Fig. 11 is a schematic diagram of a model heat preservation control unit;

Fig. 12 is a schematic diagram of the output metering unit;

Fig. 13 is a schematic diagram of the data acquisition and image processing unit.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

In the accompanying drawings, reference numerals indicate as follows: 101 injection unit, 102 model body, 103 bottom water temperature control unit, 104 bottom water pressure control unit, 105 data acquisition and image processing unit, 106 output metering unit, 107 model insulation Control unit, 701 water source, 702 high-pressure metering pump, 703 steam generator, 801 simulated injection well, 802 edge water, 803 edge water seepage layer, 804 model body insulation layer, 805 bottom water, 806 bolt, 807 simulated production well, 808 Pressure monitoring point (pressure guiding tube), 809 Temperature monitoring point (thermocouple), 810 Bottom water infiltration layer 901 Circulating water bath, 902 Bottom water, 903 First temperature sensor, 904 Heat exchanger, 1001 Pressure sensor, 1002 First Pressure gauge, 1003 buffer container, 1004 edge water, 1005 high-pressure metering pump, 1101 second temperature sensor, 1102 third temperature controller, 1103 central rotating shaft, 1104 insulation cover, 1105 model body, 1106 heater, 1201 model body, 1202 simulated production well, 1203 back pressure valve, 1204 second pressure gauge, 1205 gas source, 1206 cooler, 1207 measuring cylinder, 1301 microcomputer, 1302 data acquisition module, 1303 pressure sensor, 1304 fourth temperature sensor. In Figures 2-5, "△" indicates injection wells, and "○" indicates production wells. In Fig. 6, "-" indicates a horizontal well and "○" indicates a vertical well.

In more detail, referring to and further explaining in conjunction with the accompanying drawings, in Fig. 1, in the two-dimensional proportional physical simulation device for steam flooding of heavy oil reservoirs with bottom water according to the present invention, the positional relationship between the bottom water layer and the edge water layer can be: One position relationship is that the injection well of the edge water layer and the model body are located on the same side, and the bottom water layer is located at the lower part of the model body; the second position relationship is that the edge water layer and the production well of the model body are located on the same side, and the bottom water layer is located at The lower part of the model body. The change point of the second positional relationship relative to the first positional relationship is that the injection well and the production well exchange positions.

As shown in Figures 1 to 13, Fig. 1 is a two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with bottom water according to the present invention. The two-dimensional proportional physical simulation device for steam flooding in heavy oil reservoirs with bottom water of the present invention includes There are 7 parts including injection unit, model body, bottom water temperature control unit, bottom water pressure control unit, model heat preservation unit, output measurement unit, data acquisition and image processing unit.

The injection unit is used to inject wet steam into the model body with a speed of (20-100cm ³ /min), a temperature of (120-350°C) and a dryness of (20-80%), and the injection speed, temperature, and dryness adjustable.

The model body is used to simulate the actual reservoir. The model body can be flipped 360° in the radial direction and 45° in the axial direction, and can simulate formation dip angles at any angle. Figure 2-6 is a schematic diagram of the well pattern layout. The well pattern layout includes five-point, seven-point, nine-point, row-column well pattern and vertical well-horizontal well combination (as shown in Figure 2-6). The injection and production wells of the five-point well pattern are evenly distributed, and the positions of adjacent well points form a square. The steam injection well is in the center of the square of the production well, forming an injection-production unit. The ratio of the number of injection-production wells is 1:1; the seven-point well pattern Two steam injection wells are sandwiched between two adjacent oil production wells in each well row arranged according to the equilateral triangle well pattern, and the center of the equilateral triangle composed of three oil production wells is a steam injection well. Each steam injection well is related to three surrounding oil production wells, and each oil production well is affected by six steam injection wells. The injection-production well ratio is 2:1; each unit of the nine-point well pattern is a square, with a production well in the middle and eight steam injection wells around it. Four steam injection wells are on the four corners of the square, and four steam injection wells are on the four sides of the square. The ratio of the number of injection and production wells is 3:1; the arrangement of injection and production wells in the well pattern is a row of production wells and a row of steam injection wells, steam injection wells and production wells form a rectangle, and the ratio of injection and production wells is 1:1 ; The vertical well-horizontal well combination mode is that the horizontal well is drilled in the middle of two rows of vertical wells, and is located in the lower part of the oil layer, and the two rows of vertical wells are used for steam injection, and the horizontal wells are produced.

The bottom water temperature control unit is used to control the temperature of the bottom water body, and has the functions of heating, constant temperature and cooling.

The bottom water pressure control unit is used to control the pressure of the bottom water. The bottom water pressure reflects the energy of the bottom water body and has the functions of constant pressure and decreasing pressure.

The model insulation unit is used to raise the temperature of the model body and control the constant temperature to simulate the initial temperature condition of the reservoir, that is, the temperature before the reservoir is exploited.

The output metering unit is used to cool the output fluid, control the production pressure, collect the output fluid, measure the output oil and water, and analyze the production dynamic characteristics of steam injection oil recovery, that is, oil production, liquid production, and water content , oil-steam ratio, recovery degree and time. Among them, the oil-steam ratio is the ratio of how many tons of steam can be injected to extract one ton of crude oil when steam injection is used to develop the reservoir; the recovery degree is the percentage of the cumulative oil production to the original geological reserves during the development of a reservoir at any time.

The data acquisition and image processing unit is used to monitor the temperature and pressure inside the model body, and generate temperature field and pressure field maps in real time on the computer to control the bottom water pressure and the pressure difference between injection and production.

Further, as the injection unit shown in FIG. 7 , the injection unit includes a water source 701 , a high-pressure metering pump 702 , and a steam generator water source 703 . The high-pressure metering pump 702 can be a high-precision flow pump, and the steam generator water source 703 can be a steam generator with a controllable dryness. The inlet port of the steam generator and the outlet port of the controllable dryness steam generator are connected to the inlet port of the injection well of the model body; the steam outlet of the controllable dryness steam generator is within 0.5 meters from the injection well.

The model body shown in Figure 8, the model body shell is a cuboid shell welded by stainless steel plates and flanges and cover plates are respectively arranged on the front panel and the rear panel of the cuboid shell; interface, the cover plate on the rear panel has interfaces for simulated injection wells, simulated production wells, thermocouples and pressure pipes; graphite pads are used between the cover plates on the front panel and the cover plate on the rear panel and the shell flange of the model body , sealed by fastening bolts; the inner side of the model body shell is surrounded by a heat insulation layer, and a heat-resistant inorganic adhesive is used to coat and bond oil-repellent and water-repellent heat insulation materials.

The simulated injection well and simulated production well are all stainless steel pipes with a diameter of 6mm. The above slots simulate the perforated well sections of injection wells and production wells on site, and the positions of the slots are determined after proportional modeling according to the perforated well sections of on-site injection wells and production wells. Thermocouples and pressure measuring points are arranged in the oil layer, the transverse distance between thermocouples and pressure measuring points is 5cm, and the longitudinal distance between thermocouples and pressure measuring points is 3.5cm or 2.5cm. The part outside the edge water layer and bottom water layer inside the model body is the "oil layer", which is used to monitor the development of temperature field and pressure field in the steam flooding physical simulation test in real time.

There are 9 × 21 temperature sensors distributed inside the oil layer, and one branch is distributed in the bottom water layer, edge water layer or bottom water layer. 5×6 pressure sensors are distributed inside the oil layer, and 1 branch is distributed in the bottom water layer, edge water layer or bottom water layer.

The bottom water temperature control unit shown in Figure 9, the bottom water temperature control unit includes a heat exchanger, pipelines, and a circulating water bath, the heat exchanger is located inside the bottom water layer, the circulating water bath is located on the side of the model body, and the outlet of the circulating water bath The end is connected to the inlet section of the heat exchanger, and the outlet end of the heat exchanger is connected to the inlet end of the circulating water bath to form a loop.

The bottom water pressure control unit shown in Figure 10, the bottom water pressure control unit includes a pressure sensor, a buffer container, a high-precision flow pump, the buffer container and a high-precision metering pump are located on one side of the model body, and the inlet port of the bottom water layer is connected to the The outlet port of the buffer container is connected, the upper end of the buffer container is connected with a pressure gauge, and the inlet port of the buffer container is connected with the outlet port of the high-precision metering pump.

The model heat preservation unit shown in Figure 11, the model heat preservation unit includes a temperature sensor, a heater, a heat preservation jacket, and a temperature controller. On one side, the temperature sensor, heater and temperature controller are connected.

The output metering unit shown in Figure 12, the output metering unit includes a cooler, a back pressure valve, a liquid collector (graduating cylinder), the outlet of the simulated production well is connected to the inlet of the back pressure valve, and the upper part of the back pressure valve is connected to Place the graduated cylinder under the outlet of the air source, pressure gauge and the lower part of the back pressure valve.

The data acquisition and image processing unit shown in Figure 13, the data acquisition and image processing unit includes hardware and software two parts, hardware includes temperature sensor, pressure sensor, data acquisition module, microcomputer, signal line and data of temperature sensor, pressure sensor The acquisition module is connected, and the data acquisition module is connected with the microcomputer.

The specific experimental steps of using the steam flooding two-dimensional proportional physical simulation device for heavy oil reservoirs with bottom water of the present invention are as follows:

The first step is to establish a two-dimensional proportional physical model of steam flooding in heavy oil reservoirs with bottom water: install simulated injection wells, simulated production wells, bottom water temperature control units, and bottom water pressure control units. The bottom water layer is located at the bottom of the model body. Fill the sand in the oil layer, install the front cover of the model body, and tighten the bolts to seal;

The second step is process connection: the injection unit is connected to the simulated injection well of the model body, the output metering unit is connected to the simulated production well of the model body, and the pressure sensor, temperature sensor, and data acquisition module are connected to the microcomputer in turn. The simulated injection well is connected with the injection unit, and the simulated production well is connected with the metering unit;

The third step is to establish the initial temperature conditions of the reservoir. Start the model insulation unit, raise the temperature of the model body and control the constant temperature, and simulate the initial temperature conditions of the reservoir;

The fourth step is to simulate the saturated water of the oil layer and measure the pore volume of the oil layer;

The fifth step is to simulate saturated oil in the oil layer, start the bottom water pressure control unit, control the pressure of the bottom water, and obtain the initial oil saturation of the simulated oil layer and the initial pressure condition of the simulated oil layer;

The sixth step is steam injection for oil recovery. Wet steam is injected at a rate of (20-100cm ³ /min), at a temperature of (120-350°C) and at a dryness of (20-80%), and the output metering unit is used to collect the output fluid . Bottom water pressure control is carried out according to the change of oil field production pressure;

In the seventh step, the output fluid is separated. Measure oil output, water output, liquid output, oil-steam ratio, recovery degree;

The eighth step is to analyze the production dynamic characteristics of steam injection recovery. That is, the relationship curve law of oil production, liquid production, water cut, oil-steam ratio, recovery degree and time.

The technical scheme of the above-mentioned invention is realized based on the following research basis of the inventor of the present application below, and the research basis described below of the present invention is organically combined with the technical scheme of the invention described above: when only studying bottom water intrusion, the Edge water can be closed or eliminated.

1. Working principle of two-dimensional proportional physical simulation of steam flooding in bottom water reservoirs

The basis of the proportional physical simulation is the similarity criterion. According to the similarity criterion of the proportional physical simulation of steam flooding, the parameters of the reservoir prototype are converted to obtain a set of model control parameters. Drive two-dimensional scale physical model. According to the calculation formula of cumulative water influx of edge water and bottom water reservoirs, the cumulative water influx of edge water and bottom water reservoirs is calculated. Bring the model parameters into the calculation formula of the cumulative water intrusion of the edge water and bottom water to obtain the cumulative water influx of the model edge water and bottom water.

L-well spacing;

R-similarity ratio;

m - physical model;

f - oil field prototype;

Δρ-oil-vapor density difference;

ΔP-production differential pressure;

t - time;

α - thermal diffusivity;

q - injection speed;

K-permeability;

P - pressure;

T - temperature.

2. The calculation method of cumulative water influx in edge water and bottom water reservoirs is as follows:

1. Edge water reservoirs

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; B</span>}\underset{\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; t</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}\mathrm{<span\; class="notranslate">\; \&Delta;P</span>}<span\; class="notranslate">\; \&CenterDot;</span>\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span>$

B=φbhLC _e

${\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; =</span>\frac{\mathrm{<span\; class="notranslate">\; 0.01</span>}{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}}{\mathrm{<span\; class="notranslate">\; \&phi;</span>}{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}{\mathrm{<span\; class="notranslate">\; L</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

(1) Infinite linear water supply area

$\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\sqrt{\frac{{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}}{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}}$

(2) Limited linear water supply area, sealed outer boundary

$\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 8</span>}}{{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{<span\; class="notranslate">\; \&infin;</span>}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; no</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; -</span>\frac{{\mathrm{<span\; class="notranslate">\; no</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}}{\mathrm{<span\; class="notranslate">\; 4</span>}}<span\; class="notranslate">\; )</span>$

(3) Limited linear water supply area, the outer boundary pressure drop is constant

$\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span><span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; +</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; 3</span>}}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span>\frac{\mathrm{<span\; class="notranslate">\; 2</span>}}{{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\overset{<span\; class="notranslate">\; \&infin;</span>}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}<span\; class="notranslate">\; (</span>\frac{\mathrm{<span\; class="notranslate">\; 1</span>}}{{\mathrm{<span\; class="notranslate">\; no</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; exp</span>}<span\; class="notranslate">\; (</span><span\; class="notranslate">\; -</span>{\mathrm{<span\; class="notranslate">\; no</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; \&pi;</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span>$

The edge water is located outside the oil (gas) outer boundary of the reservoir, and the direction of intrusion into the reservoir is mainly horizontal. Edge water invasion is related to factors such as oil well working system, reservoir distribution, plane heterogeneity, and edge water body size.

2. Bottom water reservoir

${\mathrm{<span\; class="notranslate">\; W</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; B</span>}\underset{\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; t</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}\mathrm{<span\; class="notranslate">\; \&Delta;P</span>}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; Q</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; ,</span>{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; )</span>$

$\mathrm{<span\; class="notranslate">\; B</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 2</span>}\mathrm{<span\; class="notranslate">\; \&pi;</span>}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; wr</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}\mathrm{<span\; class="notranslate">\; \&phi;h</span>}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}$

${\mathrm{<span\; class="notranslate">\; t</span>}}_{\mathrm{<span\; class="notranslate">\; D.</span>}}<span\; class="notranslate">\; =</span>\frac{{\mathrm{<span\; class="notranslate">\; K</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}<span\; class="notranslate">\; \&Center\; Dot;</span>\mathrm{<span\; class="notranslate">\; t</span>}}{\mathrm{<span\; class="notranslate">\; \&phi;</span>}{\mathrm{<span\; class="notranslate">\; \&mu;</span>}}_{\mathrm{<span\; class="notranslate">\; w</span>}}{\mathrm{<span\; class="notranslate">\; C</span>}}_{\mathrm{<span\; class="notranslate">\; e</span>}}{\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; wr</span>}}^{\mathrm{<span\; class="notranslate">\; 2</span>}}}$

C _e =C _w +C _f

Bottom water is located within the outer boundary of oil (gas) in the reservoir, directly supporting oil (gas) from the bottom, and the invasion direction is vertical, that is, bottom water coning. As the oil well is put into production, the shape of the oil-water contact will change and gradually form a cone. The rising speed of the cone depends on the value of the potential gradient at the point and the vertical permeability of the rock at that point, and the rising height of the cone depends on the balance between the gravity and the vertical pressure gradient caused by the difference in the density of water and oil.

In the formula:

W _e —— cumulative water intrusion, 10 ⁴ m ³ ;

Q(t _D )—dimensionless water intrusion;

ΔP—total pressure drop of reservoir, MPa;

L——well spacing, m;

B——water intrusion coefficient;

t _D ——dimensionless time;

r _D ——dimensionless radius;

C _e ——comprehensive compressibility coefficient of water area, MPa ^-1 ;

C _w ——Water compressibility coefficient, MPa ^-1 ;

C _f —rock compressibility coefficient, MPa ^-1 ;

r _wr —— radius of bottom water, m;

h—thickness of oil layer, m;

φ—rock porosity in water area;

K _w — effective permeability of water area, 10 ^-3 μm ² ;

μ _w ——water viscosity, mPa·s.

3. Control method of edge water, bottom water and bottom water in physical simulation experiment

1. Edge water reservoirs

(1) Infinite linear water supply area

Since the edge water is an infinite linear water supply area, the pressure of the edge water will not decrease. Therefore, the pressure in the edge water area is the same as the initial pressure of the reservoir, and a computer-controlled high-precision flow pump is used to keep the pressure in the edge water area constant.

(2) Limited linear water supply area, sealed outer boundary

Since the edge water is a limited linear water supply area, the outer boundary of the edge is sealed and there is no recharge, so the pressure of the edge water naturally decreases. Therefore, the pressure in the edge water area is the same as the initial pressure of the reservoir, and the high-precision flow pump does not supply water, and the pressure in the edge water area changes with the change of the injection-production pressure difference of the simulated oil layer.

(3) Limited linear water supply area, the outer boundary pressure drop is constant

Since the edge water is a finite linear water supply area, the pressure drop at the outer boundary is constant. Therefore, the pressure in the edge water area is the same as the initial pressure of the reservoir, and the pressure drop in the edge water area is constant by using a computer-controlled high-precision flow pump.

2. Bottom water reservoir

Calculate the production pressure difference of the model, the production time and the cumulative water intrusion of the bottom water, and use the computer to control the change rate of the production pressure difference and the water intrusion rate of the bottom water.

3. Bottom water reservoir

Calculate the production pressure difference of the model, the production time and the cumulative water intrusion of the bottom water, and use the computer to control the change rate of the production pressure difference and the water intrusion rate of the bottom water.

4. The physical simulation experiment is arranged for the temperature and pressure monitoring points of edge water, bottom water and bottom water

1. Edge water reservoirs

The temperature monitoring points in the horizontal direction corresponding to the perforation positions of the injection and production wells are intensified, and the edge water invasion radius is identified through the temperature change rate and pressure field change.

2. Bottom water reservoir

The longitudinal temperature monitoring points of the oil layer are dense, and the bottom water invasion height is identified through the temperature change rate and pressure field change.

3. Bottom water reservoir

The horizontal and vertical temperature monitoring points corresponding to the perforation positions of injection and production wells are intensified, and the radius and height of bottom water invasion are identified by temperature change rate and pressure field change.

Apparently, the above-mentioned embodiments are only examples for clearly illustrating the present invention, rather than limiting the implementation. For those of ordinary skill in the art, on the basis of the above description, other changes or changes in different forms can also be made, and it is not necessary and impossible to exhaustively enumerate all implementation modes here. The obvious changes or variations derived therefrom are still within the scope of protection of the present invention.

Claims (6)

1. an oriented perforating steam flooding two-dimensional proportion physical simulation device, it comprises injection unit, model ontology, end coolant-temperature gage control unit, end water pressure control unit, model heat-insulation unit, output metering units and data acquisition and graphics processing unit;

Injection unit, for injecting the moist steam of adjustable injection rate, temperature and mass dryness fraction in model ontology, injection rate scope is 20cm ³/ min ~ 100cm ³/ min, temperature range are 120 DEG C ~ 350 DEG C, mass dryness fraction scope is 20% ~ 80%;

Model ontology, for simulating actual oil reservoir, model ontology can radial 360 °, axially 45 ° of upsets, can simulate arbitrarily angled stratigraphic dip;

End coolant-temperature gage control unit, for controlling the temperature of end water body, has heating, cooling, temperature incubation function;

End water pressure control unit, for controlling the pressure of the end water of end water body, the size of end water pressure reflection end water energy, has the function of constant pressure and pressure decline;

Model heat-insulation unit, for model ontology heat up and thermostatic control, the initial temperature condition of simulating oil deposit, namely oil reservoir unmind before temperature;

Output metering units, is collected in graduated cylinder by model ontology produced fluid after cooling, and metering oil production, Liquid output, for the Stress control of simulated production well; Be used for analyzing the characteristic of production dynamic of steam injection recovery, i.e. oil production, Liquid output, moisture content, gas oil ratio, recovery percent of reserves and the relation of time; When wherein gas oil ratio is steam injection development oil reservoir, inject the ratio that how many tons of steam could exploit one ton of crude oil; Recovery percent of reserves is the percentage that in an oil reservoir development to arbitrary time, cumulative recovery accounts for original oil in place;

Data acquisition and graphics processing unit, for controlling end water pressure, injection production pressure difference change, temperature, pressure monitoring in model ontology, and generate thermal field, pressure field pattern in real time at computer;

Wherein, described model ontology comprises model ontology shell, isolation layer, bottom aquifer and limit water layer, front and rear cover plate, graphite pads, fastening bolt, simulated injection well, simulated production well, temperature pick up, pressure sensor and temperature sensor interface and pressure sensor interface; This model ontology shell is the cuboid housing that is welded of corrosion resistant plate and arranges flange and cover plate respectively on cuboid housing front panel and rear board; Without interface on cover plate on front panel, the cover plate on rear board there are simulated injection well, simulated production well, hot line even summation pressure guiding pipe interface; Cover plate on front panel and the cover plate on rear board and adopt graphite pads between model ontology housing flange, sealed by fastening bolt; The inner side surrounding of model ontology shell is isolation layer, have employed refractory inorganic binder and carries out applying and hate the thermal insulation material of profit with boning;

Simulated injection well, simulated production well are the stainless steel tube that diameter is 6mm; At the perforated interval of simulated injection well and aboveground of simulated production fluting simulated field Injection Well, producing well, the position of fluting is determined after ratio modelling according to the perforated interval of on-the-spot Injection Well, producing well; Thermocouple and pressure-measuring-point is laid, thermocouple and pressure-measuring-point horizontal spacing 5cm, thermocouple and pressure-measuring-point longitudinal pitch 2.5cm in oil reservoir; Part outside model ontology internal edges water layer, bottom aquifer is " oil reservoir ", for the thermal field in Real-Time Monitoring steam flooding physical simulation experiment, pressure field development condition; Temperature pick up, oil reservoir inside distribution 9 × 21, distributes each 1 at bottom aquifer, limit water layer; Described pressure sensor, oil reservoir inside distribution 5 × 6, distributes each 1 at bottom aquifer, limit water layer;

Described injection unit comprises water source, flow accuracy is not more than the high-precision flow pump of 1.0%, controlled mass dryness fraction steam generator, water source connects the arrival end of high-precision flow pump, high-precision measuring delivery side of pump end connects the arrival end of controlled mass dryness fraction steam generator, the simulated injection well arrival end of the port of export link model body of controlled mass dryness fraction steam generator; Within controlled mass dryness fraction steam generator steam (vapor) outlet distance Injection Well 0.5 meter.

2. oriented perforating steam flooding two-dimensional proportion physical simulation device according to claim 1, is characterized in that, the flange quantity that cuboid housing front panel and rear board are arranged respectively is two.

3. oriented perforating steam flooding two-dimensional proportion physical simulation device according to claim 1, is characterized in that, the simulated injection well location of limit water layer and model ontology is in homonymy, and bottom aquifer is positioned at the bottom of model ontology.

4. oriented perforating steam flooding two-dimensional proportion physical simulation device according to claim 1, it is characterized in that, the simulated production of limit water layer and model ontology is positioned at homonymy, and bottom aquifer is positioned at the bottom of model ontology.

5. oriented perforating steam flooding two-dimensional proportion physical simulation device according to claim 1, it is characterized in that, coolant-temperature gage control unit of the described end comprises heat exchanger, pipeline, circulator bath, heat exchanger is positioned at the inside of bottom aquifer, limit water layer is positioned at the side of model ontology, bottom aquifer is positioned at the bottom of model ontology, circulator bath is positioned at model ontology rear, the port of export of circulator bath is connected with the entrance of heat exchanger, the port of export of heat exchanger is connected with the arrival end of circulator bath, circulator bath, heat exchanger, pipeline forms loop, realize water circulation, for controlling the temperature of end water.

6. use a method for arbitrary described oriented perforating steam flooding two-dimensional proportion physical simulation device of claim 1-5, it comprises the steps:

The first step, set up oriented perforating steam flooding dimensional proportions physical model: simulated injection well, simulated production well, end coolant-temperature gage control unit, end water pressure control unit are installed, bottom aquifer is positioned at the bottom of model ontology, load oil reservoir sand, model ontology front shroud is installed, sealing of bolting on;

Second step, flow process connects: injection unit is connected with the simulated injection well of model ontology, and output metering units is connected with the simulated production well of model ontology, pressure sensor, temperature pick up, data acquisition module, is connected with microcomputer successively; Simulated injection well is connected with injection unit, and simulated production well is connected with output metering units;

3rd step, sets up initial temperature of reservoir condition: Boot Model heat-insulation unit, heats up and thermostatic control to model ontology, the initial temperature condition of simulating oil deposit;

4th step, simulation oil reservoir saturation water, measures the voids volume of oil reservoir;

5th step, simulation oil reservoir saturated oils, starts end water pressure control unit, controls the pressure of end water, obtains the initial pressure condition simulating the initial oil saturation of oil reservoir and simulation oil reservoir;

6th step, steam injection recovery, injection rate is 20 ~ 100cm ³/ min, temperature are 120 ~ 350 DEG C, mass dryness fraction is the moist steam of 20 ~ 80%, and output metering units collects produced fluid; The situation of change that end water pressure controls to produce according to Oil Field pressure is carried out;

7th step, produced fluid is separated, metering output oil mass, the output water yield, output liquid measure, gas oil ratio, recovery percent of reserves;

8th step, analyzes the characteristic of production dynamic of steam injection recovery, i.e. oil production, Liquid output, moisture content, gas oil ratio, recovery percent of reserves and the relation curve rule of time.