RU2528306C1 - Development method for two production facilities of multilayer oil deposit - Google Patents

Abstract

FIELD: oil and gas industry.SUBSTANCE: method includes identification of production facilities with terrigenous type of reservoir developed by producers and injectors, optimisation of the development system, oil production through producers, injection of working fluid through injectors. According to the invention two production facilities are identified, which are to be the second and the seventh facilities counting from below for ten facilities at the whole deposit with share of more than 85% of remaining oil reserves. Development of the second facility is made up to the final stage, when high water cut of the product is obtained, while the seventh facility is developed up to the third stage. Rates of development are aligned for the facilities. For this purpose ratio of the producers at the second and seventh facilities are set within limits of (3.3-3.5):1 and the ratio of injectors - within limits of (6.0-6.5):1. At the second facility vertical and horizontal producers and injectors are drilled with the following ratio of vertical and horizontal wells - (2.5-3.0):1. Offshoots and horizontal offshoots are drilled from well in the non-operating stock in the ratio of (3.0-3.3):1. 10-12% of well in the operating stock at this facility are converted into injectors. At the seventh facility vertical producers of small diameter and injectors are drilled with the ratio of (3.2-3.4):1. 2.5-3.5% of producers from the united stock of the second and seventh facilities are converted to the seventh facility. 0.4-0.5% of injectors from the stock at the second facility is converted to the second and seventh facilities using equipment for dual injection. Offshoots are made from wells of the nonoperating stock in the volume of 2.9-3.1% of the common stock of producers at the seventh facility. Associated water is used for maintenance of reservoir pressure. For the first three years at the second facility 7-8% of new wells of the total planned quantity are drilled and 16-18% offshoots and horizontal offshoots are made of the total planned quantity. For the fourth year and further on 2.1-2.5% of new wells of the total planned quantity are drilled annually and 5-7% offshoots and horizontal offshoots are made of the total planned quantity. For the seventh facility for the first three years 14-15% of new wells of the total planned quantity are drilled. During following years, annually, 2.5-3.5% of total planned quantity of new wells is drilled, 7-11% of offshoots and horizontal offshoots are made, and 2.6-3.2% of wells are converted from the second facility of the total planned quantity to be converted from the second facility.EFFECT: improving uniformity of the facilities development at multilayer deposit and increasing oil recovery.1 ex

Description

The invention relates to the oil industry and may find application in the development of two production facilities of a multilayer oil field with a terrigenous reservoir type.

A known method of developing a multilayer oil field, according to which the selection of oil through production wells from the lower productive horizon, the injection of a working agent into the lower production horizon, the selection of oil through production wells from the upper production horizon and compaction of the network of wells of the upper horizon. The selection of oil through production wells from the upper productive horizon is carried out until the reservoir pressure is reduced by 10-40%, while compaction of the grid of wells on injection wells operating on the lower horizon, perforation is performed in the interval of the upper horizon. A simultaneous-separate injection of the working agent into the lower and upper horizons is performed. When uploading to the upper horizon, the injection volume is set equal to the required compensation volume over the site, and the effect is monitored for reacting production wells. If there is an effect confirmed by an increase in the current bottomhole pressure at production wells of at least 10%, injection flow rate is limited to 20-80% of the initial one and the production is intensified by reacting production wells (RF Patent No. 2474676, publ. 10.02. 2013).

Closest to the proposed invention in technical essence is a method of developing a multilayer oil field in which production facilities are distinguished, a grid for the location of production and injection wells is drilled, wells are drilled, oil is extracted from production wells and the displacing agent is injected into injection wells. The life of the field’s reserves is close to the average guaranteed service life of the wells, in which, for technical reasons, no more than 20% of the production well stock is eliminated. For this purpose, a common through hole grid is drilled for a group of field deposits with an increase in the number of wells and accelerated development time. At the same time, the exploitation of the field is carried out by the entire fund of production wells by sequentially selecting products from an individual deposit or a group of reservoir deposits combined by jumpers of a non-collector with a thickness of not more than 30 m, in decreasing order of their productivity, starting with the most productive ones (RF Patent No. 2307923, publ. 10.10 .2007 - prototype).

A disadvantage of the known technical solutions is the uneven production of oil reserves and the associated low oil recovery of the field.

The proposed invention solves the problem of increasing the uniformity of the production of multilayer deposits and increasing oil recovery.

The problem is solved in that in the method for the development of two production facilities of a multilayer oil field, including the selection of production facilities developed by production and injection wells, optimization of the development system, selection of reservoir products through production wells and injection of a working agent through injection wells, according to the invention, two production facilities are distinguished , which account for more than 85% of the residual geological oil reserves and are the second and seventh at account from the bottom of ten objects of the entire field, the development of the second object is carried out to the final stage and high water cut of the reservoir products, and the seventh to the third stage of development, the development rates are equalized, for which the ratio of production wells of the second and seventh objects is set at (3.3 -3.5): 1, and injection wells - within (6.0-6.5): 1, at the second facility, vertical and horizontal production and injection wells are drilled with a ratio of vertical and horizontal wells (2.5-3, 0): 1, drilled from idle well wells, lateral shafts and lateral horizontal shafts in the ratio (3.0-3.3): 1, 10-12% of the wells of the producing fund of this facility are converted into injection wells; vertical production wells of small diameter and injection wells are drilled at the seventh object ratio (3.2-3.4): 1, transfer 2.5-3.5% of production wells from the total stock of the second and seventh production facilities to the seventh facility, transfer 0.4-0.5% of injection wells from the stock of the second wells production facility for the second and seventh facilities using by using equipment for simultaneous and separate injection, 0.7-0.8% of the wells of the seventh object’s production fund are transferred to injection wells, including 50-60% of wells with simultaneous-separate injection to both facilities, perform sidetracking from wells of idle stock in the amount of 2.9-3.1% of the total stock of producing wells of the seventh facility, associated formation water is collected from both facilities, mixed and It is prepared for a reservoir pressure maintenance system, such water is used as a working agent for injection through injection wells at the second and seventh facilities, while in the first three years, 7-8% of the total amount planned for the storm is drilled at the second facility new wells are drilled and 16-18% of the total number of planned lateral and lateral horizontal shafts are planned for the fourth year and then 2.1-2.5% of new wells are drilled annually of the total number planned for drilling and 5-7% Of the total number of lateral and lateral horizontal shafts planned for wiring, over the first three years, 14-15% of the total number of new wells planned for drilling are drilled in the seventh facility, 30-35% of the lateral and lateral horizontal shafts are drilled, transferred from the second facility 9, 0-9.3% plan During the following years, 2.5-3.5% of the total number of new wells planned for drilling are drilled, 7-11% of lateral and lateral horizontal shafts are drilled from the second facility, 2.6- 3.2% of wells planned for transfer from the second facility.

SUMMARY OF THE INVENTION

The oil recovery and the pace of development of an oil field production facility is mainly influenced by the developed development system. The uneven development of the multi-layer field development facilities causes unreasonable expenses for oil dehydration, long-term maintenance of the field development elements, and unproductive expenses for the reservoir pressure maintenance system. The proposed invention solves the problem of increasing the uniformity of the development of multilayer deposits. The problem is solved as follows.

The method is implemented as follows.

In a multilayer field, consisting of 10 objects, two independent development objects are distinguished: the second and seventh, when counted from below, represented by reservoir-vaulted deposits with a terrigenous reservoir type. The development of facilities is carried out with the maintenance of reservoir pressure by injection of a working agent - formation water. The second object is at the final stage of development, characterized by high water cut, consists of two horizons, the seventh - in the third stage, consists of one horizon. The share in the residual geological reserves of these two objects amounts to more than 85%.

In connection with the entry of the second object into the final stage of development, the separation of the layers of one object is relevant. This is due to the fact that at the beginning both horizons of the field were developed by a single filter with the development of reserves according to the “bottom-up” principle, i.e. as the watering of producing wells, the lower layers are turned off. This principle of reserves development is similar to the principle of transferring the injection front to the first rows of production wells after reaching 50% water cut of their products and is also a big mistake. Due to the fact that the reservoirs were shut off with less intensive systems and a rarer grid of wells compared to the upper reservoirs remaining in development, significant oil reserves remained undeveloped.

The spread in the number of wells, for example, 3.3-3.5, is due to the fact that a point value of 3.4 is never actually realized at the field due to the fact that part of the wells are constantly in underground or overhaul, part of the wells are in reserve or is withdrawn from the reserve, water production of new wells is uneven, etc. According to the practice of operating wells, the indicated spread covers the number of wells in operation during the year. The following scatter also meets these conditions. In the example, point values are indicated, but it should be borne in mind that these values can vary within the indicated scatter.

The rates of development of the facilities are equalized, for which the ratio of production wells of the second and seventh facilities is set within (3.3-3.5): 1, and injection wells within (6.0-6.5): 1. At the second facility, vertical and horizontal production and injection wells are drilled with a ratio of vertical and horizontal wells (2.5-3.0): 1, sidetracks and sidetracks are drilled from idle well wells in a ratio of (3.0-3.3 ): 1, 10-12% of the wells of the production fund of this facility are converted into injection wells. At the seventh facility, vertical production wells of small diameter and injection wells are drilled in the ratio (3.2-3.4): 1, 2.5-3.5% of production wells from the total stock of the second and seventh production facilities are transferred to the seventh facility, transferred 0.4-0.5% of injection wells from the fund of the second production facility of wells to the second and seventh facility using equipment for simultaneous and separate injection, 0.7-0.8% of wells of the production fund of the seventh facility are transferred to injection wells, in tons hours 50-60% of wells with simultaneous and separate injection to both facilities perform sidetracking from idle well wells in the amount of 2.9-3.1% of the total fund of producing wells of the seventh facility. Associated formation water is collected from both objects, mixed and prepared for the reservoir pressure maintenance system, such water is used as a working agent for injection through injection wells at the second and seventh objects.

In the first three years, 7-8% of the total number of new wells planned for drilling are drilled at the second facility and 16-18% of the total number of lateral and lateral horizontal shafts planned for drilling are drilled; in the fourth year and further, 2.1-2 5% of new wells annually of the total number planned for drilling and spend 5-7% of the total number of planned lateral and lateral horizontal shafts; for the seventh facility, 14-15% of the total number of new wells planned for drilling are drilled in the first three years, the wire t 30-35% of the lateral and lateral horizontal shafts, 9.0-9.3% of the wells planned for transfer from the second facility are transferred from the second facility, over the next years 2.5-3.5% of the total number of planned wells are drilled new wells are drilled, 7-11% of lateral and lateral horizontal shafts are drilled, 2.6-3.2% of the wells planned for transfer from the second facility are transferred from the second facility.

After drilling, the wells are put into operation.

Calculations show that with such an organization of development, the second and seventh objects will be developed at approximately the same time with a difference of 2-3 years. Estimated oil recovery will amount to about 52% for the two facilities instead of 50% for the project.

An example of a specific implementation of the method.

At the Romashkinskoye field, the Kynov-Pashi independent development object with an average depth of 1750 m is distinguished, which is the second when counted from below. The object is represented by reservoir-vaulted deposits with a terrigenous reservoir type, consists of two horizons: Kynovsky and Pasha. The reservoir temperature is 40 ° C, the reservoir pressure is 17.5 MPa, the porosity is 19.9%, the permeability is 374 mD, and the viscosity of the oil under reservoir conditions is 3.3 mPa * s. The development of the facility is carried out with the maintenance of reservoir pressure by water injection and is at the final stage, characterized by high water cut - more than 80%.

Also at the Romashkinskoye field, a Bobrikovsky independent development object with an average depth of 1134 m is distinguished, which is the seventh when counted from below. The object is represented by reservoir-vaulted deposits with terrigenous reservoir type, consists of one horizon. The reservoir temperature is 25 ° C, the reservoir pressure is 11 MPa, the porosity is 23%, the permeability is 1.539 D, and the viscosity of the oil under reservoir conditions is 29 MPa * s. The development of the facility is carried out with the maintenance of reservoir pressure and is in the third stage. The water content does not exceed 50%.

The share in the residual geological reserves of these two objects amounts to 85.1%.

For the further development of reserves at the Kynov-Pash operational facility, it is envisaged:

- drilling of 2172 vertical (including two exploratory) and 481 horizontal production wells;

- drilling of 820 vertical and 161 horizontal injection wells;

- Posting from an idle fund of 307 BS and 97 BGS;

- transfer of 1747 wells from producing to injection wells.

In the first three years, 275 new wells are drilled and 70 sidetracks are drilled, in the fourth year, 90 new wells are drilled and 24 sidetracks are drilled, in the fifth and sixth years, 85 new wells are drilled and 27 sidetracks are drilled each year, for the seventh, eighth and for the ninth year, 80 new wells are drilled and 27 sidetracks are drilled annually, over the next seven years, 80 new wells are drilled and 25 sidetracks are drilled annually, then the rest.

The total fund for the facility will amount to 23327 wells, including 15426 producing, 7795 injection, 106 special wells. The fund of wells for drilling is 2653 producing (including 481 GS), 981 injection (including 161 GS).

For the further development of reserves at the Bobrikovsky operational facility, it is envisaged:

- drilling 73 vertical production wells of small diameter;

- 149 horizontal production wells;

- 22 vertical and 26 horizontal injection wells;

- transfer of 698 production wells from the Kynov-Pashi production facility (including with 141 sidetracking and the use of equipment for simultaneous and separate production (ORD) at 290 wells and simultaneous and separate production and injection at 93 wells);

- transfer of 100 injection wells using equipment for simultaneous-separate injection (ORZ) with the Kyn-Pash facility;

- transfer of 34 wells from producing to injection wells (including 18 wells from oil production facilities);

- wiring of 140 wells of idle lateral well stock.

Because there is not enough water for the system for maintaining reservoir pressure at the Bobrikovsky facility, but at the Kyn-Pashiyskaya it is a lot, then the produced water separated from the oil extracted from both objects is directed to the preparation where the water is mixed, averaged, cleaned of impurities and pumped through injection wells into the second and seventh development sites.

In the first three years, 40 production wells are drilled, 46 sidetracks are drilled, 64 production wells are transferred (including from the production plan) from the Kynov-Pashi facility, during the next four years, 8 production wells are drilled each year, 15 sidetracks are drilled. , transfer (including from the ARD) from the Kynov-Pasha facility to 20 production wells, in the eighth year drill 9 production wells, conduct 15 sidetracks, transfer (including from the ARD) from the Kynov-Pasha facility 21 production well, for the ninth year, 8 production wells are drilled, 10 sidetracks are drilled, 20 production wells are being transferred (including from the ARD) from the Kynov-Pashi facility, and then the rest.

The total fund for the facility will amount to 5777 wells, including 4534 mining, 1241 injection, two special. The well stock for drilling is 222 producing (including 149 horizontal), 48 injection (including 26 horizontal).

Development is carried out until the complete economically viable development of the facility.

As a result, over the entire development period from the Kynov-Pash production facility of the Romashkinskoye oil field, during the time that was limited by watering all production wells to 98%, or by achieving a minimum cost-effective oil production rate of 1 well of 0.5 tons per day, 2223251 thousand tons of oil were produced , including 151417 thousand tons for the period after the implementation of the proposed method, achieved CIN - 0,528 d. Without the application of the proposed method in the further development of the operational facility, the cumulative oil production is 2176933 thousand tons, including 105099 thousand tons for the forecast period achieved by the recovery factor - 0.517 d. Thus, due to the application of the proposed method, the increase in recovery factor is 0.011 units.

During the time, which was also limited by watering all production wells to 98%, or by achieving a minimum cost-effective oil production rate of 1 well at 0.5 tons per day, 239,961 thousand tons of oil were produced from the Bobrikovsky production facility of the Romashkinskoye oil field, including 83188 thousand tons for the period after the implementation of the proposed method, the achieved oil recovery factor is 0.421 units. According to the prototype, during the further development of the production facility, the cumulative oil production is 196745 thousand tons, including 39972 thousand tons for the forecast period achieved by the recovery factor - 0.345 d. Thus, due to the application of the proposed method, the increase in recovery factor is 0.076 units.

In general, the oil production at two facilities is 2463212 thousand tons, the achieved oil recovery factor is 0.515 units. According to the prototype, oil production is 2373678 thousand tons, the achieved oil recovery factor is 0.497 units. The increase in the total recovery factor in two objects as a whole is 0.019 units, of which, according to the calculations:

- 0.008 - increase due to the joint use of the wells of two objects through the open-cast drill and the open cutter;

- 0.007 - an increase due to the 100% compensation required by the geological features of the site for injection by the Bobrikov site due to the use of water from the Kynovo-Pashi site;

- 0.004 - an increase due to other activities.

The development of the Kynov-Pash facility is completed 43 years after the introduction of the technology, the Bobrikov site — 46 years after the start of the activities according to the proposed method.

The application of the proposed method will allow to solve the problem of increasing the uniformity of the production of multilayer deposits and increasing oil recovery.

Claims (1)

The method of developing two production facilities of a multilayer oil field, including the selection of production facilities developed by production and injection wells, optimization of the development system, selection of reservoir products through production wells, pumping a working agent through injection wells, characterized in that there are two production facilities, for which accounted for more than 85% of the residual geological reserves of oil and being the second and seventh when counting from the bottom of ten objects of the entire field, the development of the second object is carried out to the final stage and high water cut of the reservoir products, and the seventh to the third stage of development, the rates of development of the objects are aligned, for which the ratio of production wells of the second and seventh objects is set at (3.3-3.5 ): 1, and injection wells - within (6.0-6.5): 1, at the second facility, vertical and horizontal production and injection wells are drilled with a ratio of vertical and horizontal wells (2.5-3.0): 1 drilled from idle wells nda lateral shafts and horizontal lateral shafts in the ratio (3.0-3.3): 1, 10-12% of the wells of the production fund of this facility are converted into injection wells, vertical production wells of small diameter and injection wells are drilled at the seventh facility in the ratio (3 , 2-3.4): 1, transfer 2.5-3.5% of production wells from the total fund of the second and seventh production facilities to the seventh facility, transfer 0.4-0.5% of injection wells from the fund of the second production wells to the second and seventh objects using equipment for the same of separate-separate injection, 0.7-0.8% of the wells of the seventh object’s production fund are transferred to injection wells, including 50-60% of wells with simultaneous-separate injection to both facilities, perform sidetracking from wells of idle stock in the amount of 2.9-3.1% of the total stock of producing wells of the seventh facility, associated formation water is collected from both facilities, mixed and It is prepared for a reservoir pressure maintenance system, such water is used as a working agent for injection through injection wells at the second and seventh facilities, while in the first three years, 7-8% of the total amount planned for the storm is drilled at the second facility new wells are drilled and 16-18% of the total number of planned lateral and lateral horizontal shafts are planned for the fourth year and then 2.1-2.5% of new wells are drilled annually of the total number planned for drilling and 5-7% Of the total number of lateral and lateral horizontal shafts planned for wiring, over the first three years, 14-15% of the total number of new wells planned for drilling are drilled in the seventh facility, 30-35% of the lateral and lateral horizontal shafts are drilled, transferred from the second facility 9, 0-9.3% plan During the following years, 2.5-3.5% of the total number of new wells planned for drilling are drilled, 7-11% of lateral and lateral horizontal shafts are drilled from the second facility, 2.6- 3.2% of wells planned for transfer from the second facility.