RU2704660C1 - Method for development of oil deposit using injection of carbon dioxide - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: invention relates to production of oil and can be used in methods of development of deposits with carbonate and terrigenous reservoirs containing high-viscosity oil, as well as deposits with low gas factor. Method for development of oil deposit using injection of carbon dioxide involves preparation of working agent, pumping of working agent through injection wells and extraction of extracted products through production wells with further separation of oil and associated gas. Method comprises preliminary determination of chemical composition of formation, measuring formation temperature, pressure, selected formations consisting of carbonate or terrigenous rocks with carbonate cement, with formation temperature of 31 °C and more and formation pressure from 7.38 MPa and more. During preparation of working agent, simultaneously with fuel supply, water and atmospheric air are supplied to steam generator. Obtained mixture of carbon dioxide and steam is fed into a heat exchanger. Steam is removed from the mixture. Further, the carbon dioxide gas obtained from the heat exchanger is simultaneously supplied with oxygen, fuel and water into the steam generator at a ratio of carbon dioxide to oxygen of 4:1 and a ratio of fuel to the mixture of carbon dioxide and oxygen of 1:12, respectively. On the return line combustion products are directed through the heat exchanger in the amount required to maintain the ratio of carbon dioxide and oxygen. Steam is removed from combustion products. Then, combustion products without steam are directed into steam generator, and remaining volume of combustion products is mixed with water vapor in mixer to produce working agent and pumped into injection well. Fuel used is a mixture of hydrocarbon part of associated gas and gas from the supplier, wherein the amount of the mixture of hydrocarbon portion of associated gas and gas from the supplier is varied depending on the volume of associated gas coming from the gas separator.

EFFECT: higher reliability and efficiency of the method, higher quality of fuel combustion in the oxidizer, elimination of heat loss of fuel combustion products, higher temperature of fuel combustion, higher level of environmental safety of the oil production area, control of emissions of polluting hazardous substances.

1 cl, 1 dwg

Description

The invention relates to the field of oil production and can be used in the development of deposits with carbonate and terrigenous reservoirs, including including highly viscous oil, as well as fields with a low gas factor.

Known methods of developing oil fields, which apply the injection of carbon dioxide (CO ₂ ) into the reservoir. These methods of developing oil fields are part of a group of technologies under the general name of miscible displacement methods.

There is a known method of developing an oil field using CO ₂ (patent RU No. 2486334, IPC ЕВВ 43/24, С09К 8/592, published in Bulletin No. 18 dated 06/27/2016), which includes injecting steam into an injection well, heating the reservoir with by creating a steam chamber, taking oil through the production well, injecting produced water into the injection well after reaching the design value of the residual oil saturation and canceling the steam injection, determining the concentration of bicarbonate ions in the produced water. Injection of produced water with a concentration of bicarbonate ions of at least 3 g / l, and with a concentration of bicarbonate ions in produced water of less than 3 g / l at a temperature in the steam chamber above 100 ° C, urea is additionally introduced into the produced water. After the temperature in the steam chamber drops below 100 ° C, sodium or ammonium carbonate or sodium or potassium hydrogen carbonate are introduced into the produced water, decomposing with the release of CO ₂ under the action of heat accumulated in the steam chamber.

The disadvantages of the method:

- low environmental efficiency due to the fact that in the process of implementing the method create additional sources of CO ₂ and, as a result, due to increase the emission of greenhouse gases into the atmosphere;

- no utilization or use of CO ₂ separated from the extracted products is provided;

- the complexity of the implementation of the method associated with the complexity of the preparation of working solutions in the field;

- significant material costs for the implementation of the method due to the use of a variety of additional chemical reagents (the cost of their acquisition and storage).

There is also known a method of developing an oil field (patent RU No. 2490440, IPC ЕВВ 43/24, F04F 1/08, published in Bulletin No. 23 of 08/20/2013), including the supply of a working agent to an injection well, the selection of oil products through a producing well with subsequent separation of associated gas from oil and its combustion. Associated gas is burned with excess atmospheric air. Associated gas combustion products are cooled, water and liquid CO ₂ are sequentially separated, and the remaining gas phase is discharged. To obtain a working agent, liquid CO _{2 is} mixed with water vapor generated by heating the produced water with the products of combustion of associated gas.

The disadvantages of the method are:

- low environmental efficiency associated with the discharge of "ballast" combustion products into the atmosphere;

- low efficiency of the method due to the addition of chilled CO ₂ to the steam, which leads to a decrease in the temperature of the steam and the inexpediency of drying CO ₂ , because it will be pumped with steam;

- low efficiency of burning fuel with excess air as the amount of CO ₂ in associated petroleum gas increases during production.

The closest in technical essence to the proposed one is a method of developing an oil deposit (patent RU No. 2038467, IPC ЕВВ 43/18, publ. 06/27/1995), including the preparation of a working agent, the injection of a working agent through injection wells and selection of produced products through production wells with subsequent separation of oil, associated gas. The preparation of the working agent is carried out by supplying the associated gas obtained during the development of the oil reservoir in the boiler of a thermal power plant for combustion. Combustion products, consisting mainly of a mixture of carbon dioxide and water vapor, are sent from the boiler output to a gas-water heat exchanger, where they are cooled to 110-130 ° С and sent to a mixer, where they are mixed with O ₂ to form an artificial oxidizer, which is sent to the boiler inlet . Oxygen is obtained by separating air into oxygen and nitrogen in an air separation unit. Associated gas is used as fuel. The ratio of fuel to oxidizer during combustion is 1:10. The oxidizing agent further comprises water vapor. The ratio of O ₂ , CO ₂ and water vapor in the oxidizing agent is 1: 2: 2, respectively.

The disadvantages of this method are:

- insufficient reliability of the method, because formation conditions are not taken into account. If the reservoir temperature and pressure do not ensure the transition of CO ₂ to the supercritical state, then the progression of the CO ₂ in the gaseous state leads to a premature breakthrough of CO ₂ to the producing wells and a drop in oil production;

- the limited effectiveness of the method, due to the fact that for deposits consisting of reservoir rocks that do not contain a carbonate part, the reservoir does not react with the injected working agent and its permeability does not increase; due to the cooling of the combustion products of the fuel and oxidizer, the possibility of additional thermal action on the formation is lost to reduce the viscosity of the oil and increase its mobility due to heating;

- low quality of fuel combustion in the oxidizer, because the proposed ratio of fuel to oxidizer of 1:10 is insufficient. The lack of an oxidizing agent leads to incomplete combustion of the fuel and the formation of soot on the walls of the heat exchanger, which impairs the transfer of heat from the burning fuel to the heated medium;

- low efficiency of the method due to the lack of a stage of condensation of water vapor from the combustion products of the fuel returned back to the boiler, because when burning gas fuel with the presence of water vapor, a decrease in temperature in the combustion zone occurs;

- low environmental efficiency of the implementation of the method due to the discharge of nitrogen into the atmosphere without beneficial use.

The technical objectives of the invention are to increase the reliability and efficiency of the method by matching the chemical composition of the rocks and reservoir conditions of the developed field to the supercritical state of CO ₂ , as well as eliminating heat losses from fuel combustion products providing additional thermal effect on the reservoir, improving the quality of fuel combustion in the oxidizer due to the selected ratio fuel and oxidizer and the ratio of components in the oxidizer, an increase in the temperature of combustion of fuel due to cond nsatsii water vapor from the recirculated products of combustion, increased environmental safety area of oil, enforcement actions on polluting emissions of harmful substances regulation.

Technical problems are solved by a method of developing an oil field using carbon dioxide injection, including the preparation of a working agent, the injection of a working agent through injection wells and selection of produced products through production wells, followed by separation of oil and associated gas.

What is new is that the chemical composition of the formation is preliminarily determined, formation temperature, pressure are measured, formations consisting of carbonate or terrigenous rocks with carbonate cement, with a formation temperature of 31 ° C or more and a reservoir pressure of 7.38 MPa or more are selected, in the process of preparing the working agent, water and atmospheric air are sent simultaneously with the fuel supply to the steam generator, the resulting mixture of carbon dioxide and water vapor is sent to the heat exchanger, water vapor is removed from the mixture, then obtained from heat the carbon dioxide exchanger is sent simultaneously with oxygen, fuel and water to the steam generator, with the ratio of carbon dioxide and oxygen, respectively 4: 1 and the ratio of fuel to mixture of carbon dioxide and oxygen, respectively 1:12, along the return line the combustion products are sent through the heat exchanger in the amount necessary to maintain the ratio of carbon dioxide and oxygen, water vapor is removed from the combustion products, then the combustion products without water vapor are sent to the steam generator, and the remaining volume of combustion products is mixed They mix with steam in the mixer to obtain a working agent and pump it into an injection well, using a mixture of the hydrocarbon part of the associated gas and gas from the supplier as the fuel, while the amount in the mixture of the hydrocarbon part of the associated gas and gas from the supplier varies depending on the volume of the associated gas coming from the gas separator.

The essence of the method is as follows.

This method is used both in a newly developed field and in already developed fields.

The choice of formations consisting of carbonate or terrigenous rocks with carbonate cement, with a reservoir temperature of 31 ° C or more and a reservoir pressure of 7.38 MPa or more, provides a supercritical state of CO ₂ , which is part of the working agent injected into the formation. This prevents a premature breakthrough of the working agent to the producing wells and a drop in oil production. As a result, the use of supercritical CO ₂ in the working agent leads to a better dissolution of CO ₂ in the produced products and further separation of CO ₂ together with associated gas from the oil during separation.

The use of a mixture of the hydrocarbon part of the associated gas and gas from the supplier as a fuel regulates the consumed volume of gas from the supplier, makes it possible to implement the method for fields with different gas factors.

The combustion of fuel in the oxidizer in a ratio of 1:12 improves the quality of the process, prevents the formation of soot and its accumulation on the walls of the heat exchanger, and also improves the transfer of heat from burning fuel to a heated medium, in this case water.

The heat generated by the combustion of fuel in the oxidizer is used to generate water vapor, which is part of the working agent, and is used to heat the treated formation.

The drawing shows a flowchart of a method for developing an oil field using CO ₂ injection.

The block diagram includes: a water supply pipe 1, a heat exchanger 2, a steam generator 3, combined with a furnace (not shown), a discharge line for combustion products 4, a return line 4 ', an adjustable fitting 4'', a steam outlet line 5, a mixer 6, a line a mixture of steam and CO ₂ 7, an injection well 8, a mobile oxygen station 9, a nitrogen collection line 10, a supply line O ₂ 11, a gas line 12, a production well 13, a product pipe 14, a gas separator 15, a separated oil discharge line 16, a line separated petroleum gas 17, discharge line to condensate 18, air supply line 19.

A method for developing an oil field using CO ₂ injection is as follows.

A complex of research works is carried out at the field site, including determination of the chemical composition of the formation and measurement of formation temperature and pressure.

Formations are selected consisting of carbonate or terrigenous rocks with carbonate cement, with a reservoir temperature of 31 ° C or more and a reservoir pressure of 7.38 MPa or more. Such reservoir conditions provide a supercritical state of injected CO ₂ in the reservoir.

A working agent is prepared consisting of a mixture of combustion products and water vapor.

To do this, determine the volume of associated gas V _pg supplied via the separated gas line 17 from the gas separator 15. The volumes of the hydrocarbon part and part CO _{2 are} separated in the volume V _pg using a gas chromatograph, for example, a color analytical gas chromatograph Tsvet-800 manufactured by TsVET OJSC.

Determine the percentage of the hydrocarbon part V _SW and CO ₂ V _popCO2 :

where V _PG - the volume of associated gas;

V _SW - the volume of the hydrocarbon part of the associated gas;

V _popCO2 is the volume of a portion of the CO ₂ associated gas;

X is the percentage of hydrocarbon in the associated gas;

Y is the percentage of CO ₂ in the associated gas.

Determine the composition of the fuel. The fuel used is a mixture of the hydrocarbon part of the associated gas and gas from the supplier. Gas from the supplier - gas that meets the requirements for combustible natural gases for industrial and domestic purposes. The hydrocarbon portion of the associated gas is a mixture of gaseous hydrocarbons. The amount in the mixture of the hydrocarbon part of the associated gas and gas from the supplier is changed depending on the amount of associated gas supplied through the separated gas line 17 from the gas separator 15.

Start up the steam generator 3, which consumes the volume of fuel T m ³ / h For example, they use a GPT steam generator manufactured by the Garioni Naval concern (Italy). For this, fuel is supplied to the steam generator 3 through a gas pipeline 12.

Thus, the fuel volume T is determined by:

where V _g is the volume of gas from the supplier;

V _SW - the volume of the hydrocarbon part of the associated gas.

Simultaneously with the fuel supply, water is sent through pipeline 1 through the heat exchanger 2 to the steam generator 3 and atmospheric air through the atmospheric air supply line 19. Atmospheric air is introduced into the furnace of the steam generator 3. There is a process of fuel combustion in atmospheric air with continuous supply of water to the steam generator 3, at the outlet of the furnace of the steam generator 3, a mixture of CO ₂ and water vapor is formed. Water vapor is removed from the mixture by directing the mixture of CO ₂ and water vapor along the discharge line of combustion products 4 to a return line 4 ', and then to heat exchanger 2. In heat exchanger 2, water vapor is condensed from the mixture. Before the removal of CO ₂ from the heat exchanger 2, the supply of atmospheric air to the steam generator 3 is stopped. For this, the supply line of atmospheric air 19 is shut off. With the simultaneous supply of CO _2, O ₂ is introduced into the furnace of the steam generator 3. In this case, the volume of CO ₂ is V _{return CO2} , the volume of O ₂ V _x O ₂ . To do this, open the supply line O ₂ 11. O _{2 is} used from oxygen station 9. In the steam generator 3, the process of mixing CO ₂ and O ₂ and the formation of an oxidizing agent take place. As an oxidizing agent, a mixture of CO ₂ and O _{2 is used} in a ratio of 4: 1, respectively. This ratio of CO ₂ and O ₂ prevents the formation of soot and its accumulation on the walls of the heat exchanger 2 and the steam generator 3.

As the oxygen station 9, for example, the PKSK-10 mobile oxygen station producing O _{2 with a} purity of 95%, manufactured by OXIMAT - OXYMAT A / S, is used. The produced O _{2 is} obtained by separating the atmospheric air entering the oxygen station 9, the nitrogen remaining after the O _{2 is} separated from the atmospheric air is sent through line 10 for collection and further use in production needs, for example, hydraulic foam fracturing processes.

The oxidizing agent is prepared with a volume of V _ok in the ratio of fuel to mixture of CO ₂ and O ₂ 1:12, respectively:

where T is the volume of fuel.

Also the amount of oxidizing agent V _ok determine:

where V _obCO2 is the total volume of CO ₂ ;

V _obO2 is the total volume of O ₂ .

Since the ratio of the components in the oxidizer CO ₂ and O ₂ 4: 1, respectively, in percentage terms, V _obCO2 is 80% and U _obO2 is 20% of the volume V _ok :

The total volume of CO ₂ (V _revCO2 ) is determined by:

where V _popCO2 is the volume of separated CO ₂ coming from the gas separator 15;

V _returnCO2 is the volume of CO ₂ supplied through the return line 4 '.

Thus, the amount of CO ₂ coming through the return line 4 '(V _returnCO2 ), determine:

The total volume of O ₂ (V _obO2 ) is determined by:

where V _xO2 is the volume of O ₂ coming from the oxygen station 9;

V _{return O2} is the volume of O ₂ returning with combustion products.

Thus, the volume of O ₂ coming from the oxygen station 9 (V _xO2 ), which is supplied to the steam generator 3 through the supply line O ₂ 11, is determined:

At the moment the oxidizer enters the furnace of the steam generator 3, the fuel is burned with a volume of T and the oxidizer with a volume of V _ok with the formation of combustion products with a volume of (V _mountains ). Combustion products are a mixture of CO ₂ , water vapor and residual O ₂ , while the percentage of components in the mixture is 79.552%, 17.279% and 3.168%, respectively (Encyclopedia of heat supply http://www.rosteplo.ru/).

The combustion products of the fuel are removed from the furnace of the steam generator 3 along the exhaust gas line 4.

Next, the combustion products in the volume necessary to maintain the ratio of CO ₂ and O ₂ in the oxidizer are sent through an adjustable fitting 4 ″ along the return line 4 ’through the heat exchanger 2.

In the heat exchanger 2, from the products of combustion, consisting of a mixture of CO ₂ , water vapor and residual O ₂ , water vapor is condensed and discharged along the condensate discharge line 18, then sent to the water supply pipeline 1. Since the condensed water vapor temperature is higher than the temperature of the water supplied to the steam generator 3 through the pipeline 1, then there is an additional heating of the water. Also in the heat exchanger 2, the combustion products give off heat to the water, thereby reducing energy costs for further heating the water to water vapor. At the outlet of the heat exchanger 2, a mixture of CO ₂ and O ₂ residual which is fed into the furnace of the steam generator 3.

The volume of combustion products (V _mountains ) is determined by:

where V _cCO2 is the volume of CO ₂ in the combustion products;

V _sHH2O is the volume of water vapor in the combustion products;

V _cgO2 is the volume of residual O ₂ in the combustion products.

Also, the volume of combustion products (V _mountains ) is determined by:

Next, the contents of the volumes of CO ₂ (V _{cCO 2} ), water vapor (V _{c H 2} O) and residual O ₂ (V _c O ₂ ) in the volume of combustion products are _determined .

The volume of CO ₂ (V _cgCO2 ) is determined by:

where V _mountains is the volume of combustion products.

The volume of water vapor (V _sgH2O ) is determined:

where V _mountains is the volume of combustion products.

The volume of residual O ₂ (V _sgO2 ) is determined by:

where V _mountains is the volume of combustion products.

Because the volume of CO ₂ from combustion products (V _sgCO2) selecting _vozvrCO2 volume V of the return line 4 '. Because on the return line 4 'there is a selection of fuel combustion products, representing a mixture of CO ₂ , water vapor and residual O ₂ , then to ensure the selection of the amount of CO ₂ required to maintain the ratio of CO ₂ and O ₂ in the oxidizer, from the total volume of combustion products along the line return 4 'take the following volume out of proportion:

where V _cCO2 is the volume of CO ₂ in the combustion products leaving the furnace of the steam generator 3 along the exhaust _gas discharge line 4;

Z is the percentage of CO ₂ necessary for selection along the return line 4 'from the volume V _cCO2 to maintain the ratio of CO ₂ and O ₂ in the oxidizing agent;

V _returnCO2 is the volume of CO ₂ taken from the 4 'return line.

The volume of combustion products (V _return ) necessary to maintain the ratio of CO ₂ and O ₂ in the oxidizing agent is determined:

where V _mountains - the volume of combustion products;

Z is the percentage of CO ₂ required for selection along the 4 'return line from the volume of V _{cCO 2} to maintain the ratio of CO ₂ and O ₂ in the oxidizing agent.

In accordance with the percentage of components in the mixture of combustion products in the selected volume V _return required for the preparation of the oxidizing agent contains:

- volume of CO ₂ :

- volume of water vapor:

- volume of residual O ₂ :

The remaining volume of combustion products V _{zack is} determined:

where V _Zack - the volume of combustion products sent to obtain a working agent;

V _mountains - the volume of combustion products;

V _return - the volume taken along the return line 4 '.

The remaining volume of the combustion products is sent via line 4 to the mixer 6, where it is mixed with water vapor coming through the steam outlet line 5 from the steam generator 3. Thus, a working agent is obtained consisting of a mixture of combustion products and water vapor.

The working agent is sent along line 7. The working agent is pumped through injection well 8 into the formation.

In a formation with a temperature of 31 ° C or more and a reservoir pressure of 7.38 MPa or more, CO ₂ , which is part of the working agent, goes into a supercritical state. In this case, water vapor from the working agent gives off thermal energy to the formation and its saturating fluids, condenses and mixes with CO ₂ . When CO _{2 is} mixed with condensed water vapor, carbonic acid is formed, which transforms the calcite of the formation rock into water-soluble calcium hydrogen carbonate, which leads to an increase in the void capacity, permeability of the formation and an increase in the washed pore space of the formation and the efficiency of oil recovery from small pore capillaries.

Heated formation fluid mixed with water and associated gas - produced products. Selected production from the reservoir through the production well 13.

Through the pipeline 14, the produced products are sent to the gas separator 15, where the associated gas is separated. The separated oil and water are sent for further preparation on line 16. Associated gas on line 17 is sent to pipeline 12 to the inlet of the steam generator furnace 3. Thus, the process cycle is closed. Next, the above operations are repeated, starting from the direction from the heat exchanger 2 of the obtained CO ₂ while supplying O ₂ from the oxygen station 9.

Consider an example implementation of a method for developing an oil field using CO ₂ injection.

Conducted a set of research work. Determined the chemical composition of the reservoir, measured the reservoir temperature, pressure. We chose a formation, the rocks of which contain a carbonate part, the reservoir temperature is 35 ° C, and the reservoir pressure is 16.5 MPa.

In the process of preparing the working agent, the volume of associated gas supplied through line 17 from the gas separator 15 was determined to be 50 m ³ / h. The volume of associated gas was allocated the volume of the hydrocarbon portion, which amounted to 80%, and the volume of the portion of CO ₂ - 20%. The volume of the hydrocarbon portion was 40 m ³ / h, the volume of the CO ₂ portion was 10 m ³ / h according to formulas (2), (3).

We launched a steam generator 3, which consumes 100 m ³ / h of fuel. Gas from the supplier in the amount of 60 m ³ / h and the hydrocarbon part of the associated gas in the amount of 40 m ³ / h were used as fuel.

Simultaneously with the fuel supply, water was sent through pipeline 1 through the heat exchanger 2 to the steam generator 3 and atmospheric air through the atmospheric air supply line 19. Atmospheric air was introduced into the steam generator furnace 3. A mixture of CO ₂ and water vapor was formed at the outlet of the steam generator furnace 3. Removed from the mixture steam by means of a mixture of CO ₂ and water vapor through the discharge of combustion products 4 to the return line 4 'and then to the heat exchanger 2. Before CO ₂ output of the heat exchanger 2 stops supplying air to the steam generator 3. etog blocked the air supply line 19.

The oxidizer volume V _ok = 1200 m ³ / h was determined by the formula (5).

The total volumes of CO ₂ and O ₂ required for the preparation of the oxidizing agent were V _revCO2 = 960 m ³ / h, V _revO2 = 240 m ³ / h (according to formulas (7), (8)).

The volume of CO ₂ coming from the return line 4 ', V return CO ₂ = 950 m ³ / h (according to formula 10) was _{taken from the exhaust gas} line 4.

The combustion products of the fuel were removed from the furnace of the steam generator 3 along the line for removal of the combustion products 4 in the volume V _mountains = 1300 m ³ / h (according to the formula (14)).

Further, the volume of combustion products contained CO ₂ , water vapor, and residual O ₂ V _cCO2 = 1034.176 m ³ / h, V _cH2O = 224.627 m ³ / h and V _cO2 = 41.184 m ³ / h, respectively (according to formulas (15) - (17)).

The percentage of CO ₂ necessary for selection along the return line 4 'was _determined from the volume V _{cCO 2} to maintain the ratio of CO ₂ and O ₂ in the oxidizing agent Z = 91.86% according to formula (19).

The volume of combustion products required to maintain the ratio of CO ₂ and O ₂ in the oxidizing agent was V _return = 1194.18 m ³ / h (according to formula (20)). This volume was taken along the return line 4 'and sent to the heat exchanger 2.

In accordance with the percentage of components in the combustion products in the sampled volume necessary to maintain the ratio of CO ₂ and O ₂ in the oxidizing agent, CO _{2 was} contained in the volume V _returnCO2 = 949.99 m ³ / h, water vapor in the volume V _returnH2O = 206, 35 m ³ / h, residual O ₂ in the volume V _{return O2} = 37.83 m ³ / h (formulas (21) - (23)).

In view of the return volume V ₂ O _vozvrO2 of oxygen fed station 9 O ₂ volume V _ksO2 = 202.17 m ³ / h (formula (12)).

The remaining volume of combustion products V _zak = 105.82 m ³ / h (formula (24)) was sent via line 4 to mixer 6. In mixer 6, the remaining volume of combustion products was mixed with water vapor coming through steam outlet line 5 from steam generator 3. Thus, a working agent was obtained consisting of a mixture of combustion products and water vapor.

The working agent was sent along line 7. The working agent was pumped through injection well 8 into the formation in a volume of 105.82 m ³ / h.

Heated formation fluid mixed with water and associated gas - produced products. The selection of produced products was carried out from the reservoir through the producing well 13.

Pipeline 14 produced products were sent to the gas separator 15, where the associated gas was separated. The separated oil and water were sent for further preparation on line 16. Associated gas on line 17 was sent to pipeline 12 to the inlet of the steam generator furnace 3. Thus, the production cycle is closed. Next, the above operations are repeated, starting from the direction from the heat exchanger 2 of the obtained CO ₂ while supplying O ₂ from the oxygen station 9.

The proposed method of developing an oil field using carbon dioxide injection allows you to:

- increase the reliability and efficiency of the method;

- eliminate the heat loss of the combustion products of the fuel;

- improve the quality of fuel combustion in the oxidizer;

- increase the temperature of combustion of fuel;

- increase the level of environmental safety of the oil production area;

- ensure the implementation of measures to control emissions of harmful pollutants.

Claims (1)

A method of developing an oil field using carbon dioxide injection, including preparing a working agent, pumping a working agent through injection wells and selecting produced products through production wells, followed by separation of oil and associated gas, characterized in that the chemical composition of the formation is previously determined, formation temperatures are measured, pressure, select reservoirs consisting of carbonate or terrigenous rocks with carbonate cement, with a reservoir temperature of 31 ° C or more and reservoir pressure from 7.38 MPa or more, in the process of preparing the working agent, water and atmospheric air are sent to the steam generator simultaneously with the fuel, the resulting mixture of carbon dioxide and water vapor is sent to the heat exchanger, water vapor is removed from the mixture, then the carbon dioxide obtained from the heat exchanger is sent simultaneously with oxygen, fuel and water to the steam generator with the ratio of carbon dioxide and oxygen, respectively 4: 1 and the ratio of fuel to mixture of carbon dioxide and oxygen, respectively 1:12, along the return line the combustion products are sent through the heat exchanger in the amount necessary to maintain the ratio of carbon dioxide and oxygen, water vapor is removed from the combustion products, then the combustion products without water vapor are sent to the steam generator, and the remaining volume of the combustion products is mixed with water vapor in the mixer to obtain a working agent and pumped into the injection well, a mixture of the hydrocarbon part of the associated gas and gas from the supplier is used as fuel, while the amount of the associated hydrocarbon part of the associated gas gas and gas from the supplier vary depending on the amount of associated gas coming from the gas separator.

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