SU933957A1 - Method of mine development of oil deposit - Google Patents

Description

() METHOD OF MINING OIL LAYER

The invention relates to the development of oil fields, in particular, to methods of thermal mining of oil, and can be used in the oil industry in the development of fields with high-viscosity oils and mobile (flowing) bitumens.  At present, such deposits, as a rule, cannot be efficiently developed in the usual way, in which oil is produced by wells drilled from the surface of the earth.  Achieved in this case, oil recovery is small.  There is a known method of thermo-mining oil extraction in which vertical and inclined injection and production wells are drilled from the drilling chambers located above the oil-bearing formation.  Through injection wells, coolant is fed into the oil-bearing formation, which displaces oil to the bottom of production wells.  from the bottom of production wells, oil is lifted into the drilling chambers using an air-lift method.  The disadvantages of this method are steam breakthroughs in the mine workings and, as a consequence, a decrease in the efficiency of the process of thermo-mining oil.  There is a method of mine development of oil deposits, which consists in heating the reservoir to the temperature of fluidity by pumping coolant through injection wells, followed by maintaining the temperature by cyclically injecting steam through injection wells and cyclic oil recovery through production wells 2 J.  The disadvantage of this method is low oil recovery due to the low heating efficiency and displacement coverage.  The aim of the invention is to increase the oil recovery of the reservoir by increasing the efficiency of its formation and displacement coverage.  This goal is achieved by the fact that to heat the formation, an additional injection of heat carrier through the production wells is performed, steam is supplied through. injection wells with time intervals i C3-tL / e; where c is the heat capacity of the oil-bearing formation, J / deg, t is the thermal diffusivity of the oil-bearing formation, m / s; y is the specific gravity of the oil reservoir, N / m, 1 is the linear scale, m} tr is the dimensionless time (and oil is taken from production wells at intervals of time determined from the ratio,.   (P-ft –O 1 / "О where A is the distance between the injection and production wells, MJ dr - pressure drop in the oil reservoir between the injection wells and production wells, fj (- oil viscosity, ns / m; hi - oil plate porosity, k - oil reservoir permeability, 1); Р – О - changes in the saturation of the oil reservoir by the coolant per cycle; B is a dimensionless parameter, with the time interval t. supply of the carrier tep to injection wells is a multiple of the time interval tg for oil extraction from production wells, and the multiplicity rl-ttM Increase. oil recovery is achieved primarily as a result of heating of the oil reservoir and oil saturating it, and consequently, as a result of a decrease in the viscosity of the oil.  The need to select a multiple of the ratio of time intervals for the injection fluid cycle (for example, steam) and oil recovery cycle is justified by the fact that the geometric symmetry and ordering of elements (sections) of the mine floor is complemented by time symmetry, in terms of the multiplicity of time intervals for the injection and withdrawal cycles.  Under the conditions of multiplicity of time intervals of injection and selection cycles, the effects on filtration processes become periodic or will approach it.  Such expedient effects on filtration processes create favorable conditions for obtaining elevated values of reservoir development indicators.  For example, oil recovery increases with an additional reduction in the area (volume) of stagnant zones in the vicinity of each formation.  Improving the efficiency of the process of heating the reservoir and reducing the water content of the produced oil is carried out by regulating the operation of the production and injection wells of Telny wells according to the described principle.  FIG.  1 shows a section of mine workings with horizontal w rising insolation and production wells located radially, view in plan (mine workings are conventionally combined in one horizontal plane); in fig.  2 is a section A-A in FIG.  K in FIG.  3 - a section of mine workings with rising injection and production wells located parallel to each other, a view in plan (mine workings are conventionally combined in one horizontal plane); FIG.   - section bb in fig.  3; in fig.  5 is a timing diagram of the operation of injection and production wells (a is the operation of injection wells, b is the operation of production wells), FIG.  6 is a section of an oil reservoir drilled by a system of parallel injection and production wells (a- the work of the first group of injection wells; S — the work of the second group of injection wells); FIG.  7 is a timing diagram of the operation of wells, when the injection wells are divided into two groups (and the operation of injection wells; S is the operation of production wells); in FIG.  8 - the same, when injection and production wells are divided into groups (С | - operation of injection wells; (D - operation of production wells); FIG. 9 is the same when the average time of oil extraction from different groups of production wells is different (d- operation of injection wells; dT - operation of production wells); FIG.  10 - the same, when the time of delivery of heat transfer fluid to different groups of injection wells and the average time of oil extraction from different groups of production wells is different (O - operation of injection wells, 5 - operation of production wells); in fig.  11 - work of a group of wells when pumping coolant and oil recovery through the same wells (a - work of the first group of injection and second group of production wells, S - work of the first group of injection and first groups of production wells; -b - work of the second group of injection and the second group of production wells; Z - the work of the second group of injection and the first group of production wells).  A device for carrying out the proposed method of thermo-mining oil production includes a lifting shaft 1, a ventilation shaft 2, a mining yard 3, drifts 4, inclined mining 5 and 6, oil-bearing formation 7, working gallery 8, production wells 9 injection wells 10, boiler installation 11, onshore pipeline 12, steam supply well 13, element (section) I mine floor, conditional boundary 15 mine floor, horizontal or flat bottom clone wells 16j pipes 17, packers 18 and 19, casing. column 20.  The proposed method proceeds with the following.  A set of underground mine workings is created, which includes two shaft shafts — a lifting shaft shaft 1 (FIG.  1 - k) and the ventilation shaft 2, the mine yard 3, near-shaft mines in which the locomotive depot is located, the pumping station, warehouses, etc. d.  (not shown), drifts, inclined mine workings 5 and 6.  The drifts i build above the roof of the oil reservoir 5.  They have a slope to the horizon of about 1-3.  The development of a mine floor is carried out element by element (by sections).  All elements (sections) are identical to each other.  They may have the shape of regular polygons, for example, the shape of hexagons (FIG.  1) or rectangles (FIG.  3), as well as any other.  From drifts k, inclined mine workings 5 and 6 are built into the zone of the oil-bearing formation 7 and here at least one working gallery 8 is created.  Work gallery 8 can have a different shape: circular (FIG.  1), square, rectangular, elliptical, rectangular (FIG.  3), curvilinear or other, depending on the shape-element (area).  From the working gallery 8, 8 operational wells and 10 injection wells are drilled.  In the case of a circular working gallery 8, the indicated wells are drilled evenly over the area, along the radii of the circle (FIG.  one).  In the case of a linear working gallery (FIG. H) operational 9 and injection 10 wells are drilled evenly in area parallel to each other.  Heat carrier (for example, steam) is supplied to the wellheads of injection wells 10 from the boiler unit 11 (FIG.  2 and U) through an onshore pipeline 12 through a steam supply well 13 and underground pipelines located in drifts k (not shown).  Through the system of injection 10 and production 9 wells, the oil pump formation 7 is heated to the temperature at which the oil acquires the necessary TeKy4ectb.  For various oil fields, this temperature can vary significantly from about 80 to 250 ° C, and depends on the properties of the oil.  As a result of the dense network of injection wells 10, which have a large extent along the oil-bearing formation 7, the latter heats up evenly and quickly throughout its volume.  This is achieved due to the fact that horizontal and rising injection wells 10, stretching across the oil reservoir 7 for tens and hundreds of meters, connect its heterogeneous zones, various channels, cracks, cavities and increase the degree of oil reservoir. the oil-bearing formation of 7 cracks with their predominantly vertical distribution, high-permeable zones and cavities facilitates its rapid heating.  As the temperature of the oil reservoir 7 increases, the viscosity of the oil decreases and its fluidity increases.  In the case when injection of coolant only through injection wells 10 leads to a long period of reservoir heating, in order to intensify this process, the oil-bearing formation 7 is heated through injection 10 and 9 production wells by one of the usual methods .  The distance between the production 9 and injection 10 wells is chosen depending on the specific geological conditions, they can be both the same and different.  Oil extracted from production wells 9 and entered into the working gallery 8 is fed into the grooves, which are constructed in drifts 4.  Together with the water supplied to the grooves, the oil is transported by gravity due to the inclination of the mine workings to the horizon of the order of} -3 to installations (not shown) where it is separated from the main body of water.  Oil from the produced water can also be transported from the working gallery through inclined workings 5 and 6 and drifts k through pipelines to the specified installations for separating water by pumping its pump and.  From these installations, oil is pumped to central underground oil collectors (not shown), from where it is supplied after primary preparation and heating via pipelines through special wells l or through a shaft shaft to tank farms located on the surface of the earth.  78. The essence of the method does not change if the drifts are M (FIG.  3 and 4) will create below the oil-bearing formation 7.  Moreover, with such an arrangement, the drifts k create the best conditions for supplying oil therein from the working galleries 8.  Oil transportation in this case can be carried out by gravity.  Working gallery 8 can be created in the form of two paired mine workings (FIG.  3) as well as in the form of a single circular mine working (FIG.  2), linear or curvilinear.  In all cases, the length of the working gallery 8 is chosen, among other conditions, from the condition of reliable airing.  The ventilation system must ensure compliance with the necessary occupational health and safety standards for service personnel.  After heating the oil reservoir 7 (FIG.  2) the coolant is fed through the injection wells 10 at intervals of time determined from the relation where c is the heat capacity of the oil-bearing formation, J / deg; thermal diffusivity of a non-petroleum reservoir, m / s, linear scale, m, f - dimensionless time ().  The dimensionless time depends on the thickness of the oil reservoir 7, the temperature at the bottom of the injection wells 10, as well as the number and location of the injection wells TO.  The value of t: is determined from an equation including the indicated parameters.  For the case when the injection wells 10 are located in the roof and bottom parts of the formation, the equation for determining the dimensionless time is X V Fil-h. r - ViFiCfl tr; V - -i-gp.  h / - 1–0 temperature at the inlets where in & injection wells in the roofing and plantar parts of the reservoir, 0 - initial temperatures of the reservoir, ° & - temperature scale, X - averaged reservoir temperature, ° CJ (o. §R) ao; ) -2 | (u, :) ao; V-function KOBI, - formation thickness, m.  Oil is withdrawn from production wells 9 with intervals of time tа such that the time interval t for supplying coolant to injection wells 10 is a multiple of the time interval tj for oil withdrawal from production wells 9, the multiplicity p / t / 7f 60, where the symbol Г J means the operation of taking the whole part of the ratio of two quantities AVv "(pi-pi) fl, - (3) 2кдР where A is the distance between the injection and production wells, m; DR - pressure differential between injection and production wells, n / m; - oil viscosity, ns / m, K - oil-bearing formation permeability, D; m is the porosity of the oil-bearing plate, p-Ort is the change in the saturation of the oil-bearing formation by the coolant over the cycle; B-dimensionless parameter, depending on the nature of the phase permeabilities on the oil and the coolant, is determined from the ratio B-. ) ROM1. D to / ki.  where X I M is the reservoir permeability for oil and coolant, D 57 and VISCOSITY of oil and coolant, ns / m.   ) C, C) | ,, ((. ) f M) - xii () F (, where f () and f2 () are phase permeabilities for oil and coolant; 1 - saturation of oil-bearing formation with coolant; - saturation of non-reservoir formation at the displacement front.  The need to choose a multiple ratio of the time intervals of the injection fluid cycle (for example, steam) and the oil recovery cycle is justified, as indicated, by the fact that the geometric symmetry and ordering of elements (sections) of the mine floor. this is complemented by time symmetry, in the sense of multiplicity of intervals of time for pumping coolant and oil recovery. Under conditions of multiplicity of intervals for pumping coolant and oil sampling, the effects on filtration processes become periodic or close to it.  Such effects on filtration processes are essential in technology, as they create favorable conditions for enhanced oil recovery.  The minimum multiplicity 60 of the time interval -t for supplying coolant to injection wells, the time interval t for extracting oil from production wells is obtained by thermohydrodynamic calculations of the thermal balance of an oil-bearing formation, in which Nlraan with the heating of the oil-bearing formation takes into account heat leakage through the roof and bottom of the oil-bearing formation, as well as losses heat from the extracted oil for each cycle of oil extraction from the reservoir through production wells.  From the above expressions for t and t, the multiplicity value is determined by the formula iKupcgrU C riKupcyU C 1 (p, -rg) where all the designations are indicated above.  In all injection wells 10 developed elements (sections) 1b (Fig.  1 and 3), separated from each other by conditional boundaries 17, coolant is supplied for a certain time t, and then injection wells 10 are closed and kept closed for a time t.  In the particular case, the time t of the flow of coolant through the injection wells 10 can be equal to the time t to close them.  The complete cycle T of the operation of injection wells 10 is equal to the sum of the time t:.  and t.  l 2 Oil production is carried out cyclically through all production wells 9, both during injection of heat carrier into injection wells 10, and during their shutdown, with the time interval t, j for oil extraction from production wells 9 alternating with time interval t their stops.  In the particular case, the time interval t may be equal to the time interval t J.  The described process is conventionally shown in the timing diagram of the operation of injection and production wells (FIG.  five).  The time interval for the cycle of injection of coolant into injection wells 10 is a multiple of the time interval of the oil recovery cycle from production wells 9. t Due to the multiple ratio of the time intervals of the injection fluid cycle and the oil recovery cycle (symmetry times), the effects on filtration processes become periodic.  Such feasible effects on filtration processes create favorable conditions for further reducing stagnant zones in the vicinity of each impermeable or poorly permeable plastic inclusion.  During the supply of coolant to the oil-bearing formation 7 and the extraction of oil from production wells 9, PRO7 ISOLED the hydrodynamic displacement of oil in the formation.  During the supply of 8, the oil-bearing formation 7 of the coolant and the cessation of oil recovery from the production wells 9 in the oil-bearing formation 7 increases pressure and temperature.  Due to this, in the next sampling cycle oil is displaced from injection wells 10 to production wells 9 During the shutdown of injection and production wells, capillary impregnation of rock blocks in fractured formations and low permeability sections in heterogeneous formations and pressure redistribution occur.  When oil is withdrawn from production wells 9, there is a change in the direction of seepage flows, due to which there is an increase in the coverage of the reservoir by displacement and, as a result, oil recovery.  After creating a set of underground mines, working galleries and drilling of production and injection wells, the method is carried out as follows.  Injecting coolant (steam) through injection and production wells warms the reservoir to an average temperature of the order at which the viscosity of oil from 15,300 cP at the initial reservoir temperature of + 6 ° C decreases to a viscosity of about 30 cP.  Oil thus acquires the necessary fluidity in the reservoir.  Steam is pumped into the oil-bearing formation through injection wells with a degree of dryness of 0.8 under a pressure of 2-5 at their mouths with an interval of 1 time t determined from relation (1).  The following data is taken as the initial data: С O asccal / kg / S} -, g 3.2Gkcal / m / day / С, j 2 Ь ЗГгm.  The dimensionless time IT is determined from dependence (2) with the following data: © ei 130 ° 1 C, Ro, G 100 Pcj, - h 18.5 Gm.  For these indicators, the time-t of supplying the coolant to the reservoir is And day.  The time of shutdown of injection wells is maintained for the same duration. e.    1 day  Simultaneously with the injection of coolant, cyclic oil is taken from production wells at time intervals T determined from relation (3).  The following data are taken as the initial data: A 20CMJ; dr 2 kgf / cm; / J to m g 0,2b.  The dimensionless parameter B is determined from the dependence (C) at xl / tO; 0 Relative phase permeabilities tf () and.  are determined from known relationships.   For these indicators, the time t of oil recovery from production wells is 2.08 hours.  From the obtained values of t-values, find the multiplicity ft.  34 14. 2 l6l, 538 1 LtvJ iTToI From the multiplicity value found, the time taken to extract oil from production wells is specified from the dependence

/

 2 h 5 min. The time t4 of stopping production wells is maintained for the same duration, i.e. tj 2 h 5 min. In order to evaluate the effectiveness of the proposed method of thermo-mining oil extraction, it is compared with the method in which the heat carrier is pumped and the oil is taken off cyclically, but without observing the above relations between time t and time t. The following information is taken as the initial data for the calculation and comparison: Area of the development element, ha Average effective oil saturation of the reservoir, m Porosity Not | |) saturation Water saturation Average permeability of the reservoir, D Initial reservoir temperature, С Temperature of the reservoir after heating, s

30 1. Oil viscosity at heating temperature, cp 30 Number of injection wells, units 6t3 Number of production wells, units 121 Average length of injection wells, m 55 Average length of production wells, m 190 Indicators after 5 years of development are given in the table. Method Indicators Offered I Known Oil Recovery, Specific Steam Consumption, t / t Average Watering When implementing the proposed method in zonal non-uniform oil-bearing formations, all injection wells are divided into groups, and the transfer of coolant into each group is carried out alternately depending on the process conditions. FIG. 6 schematically shows a section of an oil reservoir 7 drilled from the working gallery B with a system of parallel injection 10 and operational 9 wells. Injection wells 10 are divided into two groups. The group includes injection wells located one after another. FIG. 6a shows the operation of the first group of injection wells 101, 10-2, 10-3, FIG. 6d is the second group of injection wells 10, 105 in the same area. FIG. 7 shows a timing diagram of the operation of injection and production wells. The cycle of operation T of two different groups of injection wells is conventionally shown. The time interval for steam supply to the first group is -, to the second - tj. In the particular case, t-j can be equal to t., The time intervals of injection cycles are multiples of the time interval of the oil extraction cycle from production wells. The stopping time of production wells depends on the physical properties of the oil-bearing formation and the oil saturating it. In the particular case, the time of oil extraction from production wells may be equal to the time of their stopping. Cyclic injection of heat transfer fluid through various groups of injection wells into the oil reservoir and cyclic oil recovery through all production wells leads to a change in the direction of filtration flows of the reservoir, you ( The development of oil, from stagnant zones, areas of the reservoir with impaired permeability, which leads to increased oil recovery. In the implementation of the proposed method in zonal and lithologically heterogeneous oil-bearing In addition, the production wells 9 are also divided into groups, and the oil is taken from each group alternately depending on the process conditions.Figure 8 shows the time t of injection of the heat transfer medium into the first group of injection wells 10, the time that injection into the second group of injection wells 10 , time tt, oil recovery from the first and second and group of production wells 9, respectively. Cyclic steam injection into various groups of injection wells with cyclic oil recovery, as well as the multiplicity of time intervals iklov injection and selection allow increase coverage displacement oil reservoir with high zonal and lithological inhomogeneity and thus improve oil recovery. When implementing the proposed method, in non-uniform fractured fractured porous and fractured cavernous porous reservoirs, oil is extracted from production wells 9 so that the time interval for the injection fluid in the injection wells 10 is cracked to the average time for oil extraction from simultaneously operating wells 9. In FIG. Figure 9 shows the timing diagram of the operation of two groups of injection and two groups of production wells, with the time t and 1l being the average time for oil recovery from different groups of production wells. Oil extraction from individual wells of each group is carried out during different time intervals, determined mainly by steam or water breakthroughs in them. This allows filtration streams to be created in the formation in such a way as to achieve the most complete coverage of the oil-bearing formation 7 by displacement, which leads to an increase in oil recovery and a decrease in the water content of the oil produced. With different time outflows of oil from the production wells 9, it is possible to prevent steam breakthroughs into the mine workings through the production wells 9, which allows for more economical use of the coolant. FIG. 10 schematically shows the general case when the time intervals of the injection fluid cycles to different groups of injection wells are different and the average times of oil extraction cycles from different groups of production wells are also different. The number of wells in different groups of injection and production wells may be the same or different. The duration of injection fluid cycles (for example, steam) to different groups of injection wells is determined by the geological and physical characteristics of the oil-bearing formation and varies from 10 to 30 days. The discharge pressure is from 1 to 20 kg / cm. The duration of oil recovery cycles from different groups of production wells vary from one to several hours. In cases where the reservoir is composed of strong (stable) rocks, in the implementation of the proposed method, the flow of coolant into the reservoir is produced through pipes 19 placed in horizontal or slightly bentholes 18 (Fig. P) equipped with one packer 20 at the bottom and the other the packer 21 is essentially in the middle part of the well, and the selection of the fluid is made through perforated holes in the casing 22 at the wellhead so that the time interval for the supply of heat carrier bodies to these pipes is a multiple of the sampling time ft through the specified perforated holes in the casing at the wellhead. According to the proposed method, the heat carrier is pumped into the oil-bearing formation and oil is extracted from it through the same wells both simultaneously and separately, depending on the established technological mode of operation of the wells. To prevent possible breakthroughs, the heat-producing fluid injected into the oil-bearing formation is supplied with two packers, one of which (the packer 20) is installed at the bottom of the well, and the other (the packer 21) is in essence. This is done in the middle part of the well 18. Drilling of the wells 18 is carried out from the working gallery 8. This can be done in the same way as described. In this case, those shown in FIG. 5 7-9 time diagrams of the work of the injection and operational deposits. In this case, the injection wells are understood as areas of the wells from their bottom to the first packer 20, and production wells refer to the sections of the wells from their mouth to the second packer 21. Supply of heat-transfer fluid and oil recovery is carried out using a system of parallel horizontal wells, divided into groups for example through one. Steam injection (Fig. Lid) is carried out through the downhole wells 1, Ш and V, and oil is taken through the perforated holes in the casing of wells II and 1Y. Steam injection (Fig. 116) continues through wells 1, P | and V, and oil is taken through the perforated holes of the same well. Due to this, the direction of filtration flows is changed, shown in FIG. 1.1ai 11 6 arrows. The sweep coverage at the wellhead increases. Steam (Fig. 11-6) is pumped through wells II and IV, and oil is taken from wells 1, W and Y. With such a change in the direction of the seepage, the reservoir coverage increases by displacing at the bottom of the wells. 7 Steam injection (Fig. Pg) and oil extraction are carried out through the same wells II and IY, which also leads to a change in the direction of oil flows in the reservoir, to an increase in the coverage and, as a result, to an increase in oil recovery. As can be seen from the above figures, when implementing these variants, filtration flows with changing directions of oil flow are created in an oil-bearing formation. With KpaTt.OM the ratio of the times of the injection fluid and oil recovery cycle times, favorable conditions are created to further reduce stagnant zones in the oil-bearing formation. The flow of coolant in the pipe 19 allows you to maintain the temperature of the bottomhole zone at a given level, and therefore, to maintain a high fluidity of oil. All this allows to intensify the process of heating the oil-bearing formation, to increase the coverage of the formation by displacement, to increase the oil recovery and the pace of development. In the implementation of the proposed method, when the oil-bearing formation is represented by poorly cemented rocks, the annular space between the walls of the wells and the tubes placed in the wells in the area between the packers 20 and. 21 are filled with quick-hardening heat-impermeable compositions (for example, cement mortar). In this case, it is not necessary to casing the well with a casing string for its entire length and install two packers. It suffices to install only one packer, essentially in the middle part of the wells, and lower the casing string 22 to the place of its installation. Good sealing of the tube space avoids steam breakthroughs into the work gallery. This, in turn, increases the efficiency of the process of thermo-mine oil production. The Formula of the Invention Method is an oilfield development mine, consisting in expanding the formation to the oil fluid temperature by injecting coolant through injection wells followed by maintaining the formation: temperature by cyclically injecting steam through injection wells and cycling oil recovery through production wells, characterized in that increase in oil recovery by increasing the efficiency of its progress and sweep coverage, to heat the reservoir chku heating medium through production wells and steam supply is carried out through injection wells at time intervals, where-C- thermal capacity reservoir, J / deg; b is the thermal diffusivity of the oil reservoir, Y is the specific gravity of the oil reservoir, tr is the linear scale, m,: G is the dimensionless time (), and oil is taken from production wells at intervals of time determined from the ratio, (p1-pg ) In akup, where A is the distance between the injection and production wells, m; when no. 19, others are the pressure drop in the oil-bearing formation between injection and production wells, N / c (; - oil viscosity, ns / m; 1- oil-bearing formation porosity; K-oil-bearing formation permeability, D; r.r is the change in saturation of the oil reservoir with coolant per cycle; B is a dimensionless parameter depending on the nature of phase permeabilities on oil and coolant, the meme time interval t for supplying the borehole reservoir to injection wells is a multiple of the time interval t multiplicity E Sources of information, which are taken into account in the examination 1. Mishakov VN, et al. Experience in the application of thermal methods in the mining of high oil fields., Petroleum, 7, No. 10, pp. 31-35. USSR author's certificate it68529, class E 21 B 43/2, 13.03.72.

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Claims (1)

The method of mine development of an oil deposit, which consists in heating the formation to the temperature of fluidity of the oil by pumping coolant through injection wells, followed by 9 933957 twenty. maintaining the reservoir temperature by cyclically injecting steam through injection wells and cyclically extracting oil through production wells, characterized in that, in order to increase oil recovery by increasing the efficiency of its warming up by displacement, an additional coolant is injected through the production wells to warm the formation, and steam is supplied through injection wells at time intervals where C ^{is the} heat capacity of the oil reservoir, J / deg; 8 - thermal diffusivity of the oil reservoir, m ^ / s, γ - specific gravity of the oil reservoir, N / m ³ ; B ~ linear scale, m, * G is dimensionless time (0 <7 ^^ 1), and the selection of oil from production wells is carried out at time intervals determined from the ratio ΊΚΛΡ where D is the distance between injection and production wells, m; dr - differential pressure in the oil reservoir between injection and production wells, H / pf ² · J 5 r - oil viscosity, ns / m; porosity of the oil reservoir; K is the permeability of the oil reservoir, D; ¹⁰ change in the saturation of the oil- ⁴ nasal reservoir with a coolant per cycle; B ^{is a} dimensionless parameter depending on the nature of the phase <5 permeabilities in oil and coolant, and the time interval for supplying the coolant to the injection wells is a multiple of the time interval t 20 oil extraction from production wells, and the multiplicity