RU92090U1 - PLASTIC PRESSURE SUPPORT SYSTEM - Google Patents

Abstract

A system for maintaining reservoir pressure, including a cluster pump station with a high-pressure pump with a discharge conduit, connected by water conduits to injection wells operating at different injection pressures and / or opened reservoirs with different reservoir properties, characterized in that the system is additionally equipped with water wells with high-pressure pumps each connected to water conduits leading to injection wells of higher discharge pressure and / or with higher requirements and to the quality of water depending on the reservoir properties of the formations, while these water conduits are connected to the discharge conduit of the cluster pumping station through an adjustable hydraulic resistance.

Description

The proposal relates to the oil industry, in particular, to a system for maintaining reservoir pressure for pumping fluid into reservoirs (to installations for flooding production reservoirs).

A well-known system for maintaining reservoir pressure (see Prince F.S.Abdulin "Oil and Gas Production" M., Nedra, 1983, p. 58-61), including a cluster pump station with a high pressure pump, water pipes from the cluster pump station to injection wells, injection wells operating at different injection pressures and / or opening formations with different reservoir properties.

A well-known reservoir pressure maintenance system (see the manual "Operation of reservoir pressure maintenance systems in the development of oil fields", ed. Zeygman Yu.V., Ufa: Publishing House UGNTU, 2007, p.181-188), including a well pump station with a high-pressure pump, water conduits from the cluster pump station to injection wells, injection wells operating at different injection pressures and / or revealed formations with different reservoir properties. These systems are accepted by us for analog and prototype.

Known reservoir pressure maintenance systems for pumping fluid into formations have the following disadvantages:

- at the cluster pump station and in the water conduits, it is necessary to maintain the maximum pressure corresponding to the injectivity level of the low-permeability formation, which leads to equipping the cluster pump stations with powerful high-pressure pumps;

- the creation of high pressures on the conduits leads to an increase in the number of gusts on them;

- used shut-off and distribution valves (for example, a fitting, a control valve, a gate valve with nozzles) on a large number of highly permeable wells for regulating the volumes of pumped process water into reservoirs with high permeability and increasing the injection pressure into reservoirs with low permeability is difficult to control, timely replacement and cannot provide “targeted” injection of water with various pressures;

- the use of fittings to control the volume of injected water into reservoirs with high permeability and to increase the injection pressure into reservoirs with low permeability significantly increases the energy costs of implementing the technology.

Wells with low permeability formations that require high injection pressures and / or wells with higher requirements for water quality depending on the reservoir properties of reservoirs for their development are identified at real facilities during field operation.

The technical task of the invention is to reduce the pressure in the water conduits connected to highly-responsive wells, due to this the use of cheaper pumping units with lower head at cluster pumping stations, a decrease in the rate of decline in the dynamic productivity of low-permeability wells and / or wells with higher requirements for water quality in dependence on reservoir properties of reservoirs due to higher quality water injection from water wells with high-pressure pumps, increase service life and reducing the likelihood of gusts in water conduits connected to highly-responsive wells by reducing working pressure, and as a result, reducing material costs for the construction, maintenance and repair of water injection systems.

The technical problem is solved by a system for maintaining reservoir pressure, including a cluster pump station with a high pressure pump with a discharge conduit connected by water conduits to injection wells operating at different injection pressures and / or opened reservoirs with different reservoir properties.

What is new is that the reservoir pressure maintenance system is additionally equipped with water wells with high-pressure pumps, each connected to water conduits leading to injection wells of a higher discharge pressure and / or with higher water quality requirements depending on the reservoir properties of the reservoirs, while water conduits are connected with a discharge conduit of the cluster pumping station through an adjustable hydraulic resistance. The drawing shows a process diagram of a system for maintaining reservoir pressure for pumping fluid into the reservoirs.

It contains a receiving conduit 1 of a cluster pump station 2, a high pressure pump 3 of a cluster pump station 2, a discharge conduit 4 of a cluster pump station 2, a comb unit 5 with valves 6, 7, 8, 9, water conduits 10, 11, 12, 13, discharge wells 14, 15, 16, 17, 18, opened the formations with high permeability, injection wells 20, 21, opened the formations with low permeability and / or with higher requirements for water quality depending on the reservoir properties of the formations. The reservoir pressure maintenance system is additionally equipped with a water well 22 with a high-pressure pump (not shown in the diagram) connected by a water conduit 23 to injection wells 20, 21 of a higher injection pressure, and / or with higher water quality requirements depending on the reservoir properties of the formations, while the conduit 23 is in communication with the discharge flow conduit 4 of the cluster pumping station 2 through an adjustable hydraulic resistance 24.

The scheme works as follows (see drawing). The conversion of one of the highly water-cut producing wells closest to the existing water conduit 11 is carried out into a water intake well 22. A water well 22 is equipped with a submersible centrifugal pump, the discharge line of which is connected by a water pipe 23 to an existing water pipe 11 and higher pressure injection wells 20, 21 and / or more high requirements for water quality, depending on the reservoir properties of the reservoirs. The productivity (supply) of the submersible centrifugal pump of the water well 22 is selected slightly higher (10-20%) of the total injectivity of the injection wells 20, 21. Moreover, the water conduit 23 is in communication with the discharge conduit 4 of the cluster pump station 2 through an adjustable hydraulic resistance 24 (for example, control valve, gate valve with fittings). A water well 22 is selected that is closest to the existing water conduit 11, based on the minimum length of the water conduit 23, which ensures minimal capital costs. Hydroresistance 24 is installed near the junction of the conduit 23 with the existing conduit 11 or near the comb unit 5, depending on the convenience of control or replacement thereof (see drawing).

On the water conduits 10, 12, 13 connecting the discharge flow pipe 4 of the cluster pump station 2 through the comb unit 5, valves 6, 8, 9 with injection wells 14, 15, 16, 17, 18, 19 with lower injection pressure (in comparison with the wells 20, 21) and, having opened formations with high permeability, installation of fittings is not required. The existing pump at the cluster pump station is replaced with a pump of a lower pressure, thereby reducing the discharge pressure of the process water of the reservoir pressure maintenance system.

They include a high pressure pump 3 of a cluster pumping station 2, which provides for the injection of process water through a discharge conduit 4, comb unit 5, valves 6, 8, 9 into injection wells 14, 15, 16, 17, 18, 19 with a lower injection pressure, and permeable formations with high permeability. They include a high-pressure submersible centrifugal pump of the water well 22, which provides injection of produced water through a water conduit 23 into injection wells 20, 21 with a higher injection pressure and / or with higher requirements for water quality. By adjusting the hydraulic resistance 24 (for example, by selecting a fitting, a control valve, valves with student nozzles), the pressure and rate of injection of produced water into the injection wells 20, 21 are regulated. In this case, the produced water is pumped by the pump of the intake well 22 into the injection reservoirs in accordance with the injection task wells 20, 21 with a higher injection pressure, and / or with higher requirements for water quality depending on the reservoir properties of the formations, and a small part of the formation water will go through the conduit 11 through the hydraulic resistance 24, the comb unit 5 and is pumped by the high pressure pump 3 of the cluster pump station 2 through the conduits 10, 12, 13 into the injection wells 14, 15, 16, 17, 18, 19.

An example of a specific implementation.

There is a task for injection into injection wells. Injection wells have the following characteristics. Injection wells 14, 15, 16, 17, 18, 19 with lower injection pressure (in comparison with wells 20, 21) and those that have opened formations with high permeability:

- well 14 - injection 220 m ³ / day at an injection pressure of 9.8 MPa, well 15 - injection 210 m ³ / day at an injection pressure of 9.8 MPa, well 16 - injection 230 m ³ / day at an injection pressure of 9.8 MPa, well 17 — injection of 220 m ³ / day at an injection pressure of 9.8 MPa, well 18 — injection of 230 m ³ / day at an injection pressure of 9.8 MPa, well 19 — injection of 220 m ³ / day at an injection pressure of 9, 8 MPa.

Injection wells 20, 21 with a higher injection pressure and / or with higher requirements for water quality, depending on the reservoir properties of the formations:

- well 20 - injection of 75 m ³ / day at an injection pressure of 12.8 MPa, well 21 - injection of 75 m ³ / day at an injection pressure of 12.8 MPa.

A high-pressure pump of type 3 of the central nervous system 63-1100 of a cluster pumping station 2 provides for the injection of water in a volume of 1330 m ³ / day into injection wells 14, 15, 16, 17, 18, 19 with a pressure of 1100 meters. The high-pressure submersible centrifugal pump ESP 160-1650 (losses due to the rise of water from the aquifer of the water well are taken into account) of the water well 22 provides injection of produced water in a volume of 150 m ³ / day into injection wells 20, 21. Moreover, a small part of produced water in a volume of 10 m ³ / day are pumped by a high-pressure pump of type 3 TsNS 63-1100 3 cluster pumping station 2, through pipelines 10, 12, 13 into injection wells 14, 15, 16, 17, 18, 19. Thus, a high-pressure pump of type 3 Central nervous system 63-1100 cluster pumping station 2 provides chku water in volume 1330 m ³ / day in the injection wells 14, 15, 16, 17, 18, 19 with a pressure of 1,100 meters, and the high-pressure pump is a submersible centrifugal ESP 160-1650 water well 22 provides a reservoir water injection in a volume of 150 m ³ / days into injection wells 20, 21. The total injection of the RPM system is 1480 m ³ / cit (61.7 m3 / h).

To ensure that the pump injects a cluster pump station for the prototype case, it is necessary to maintain a maximum pressure in the water conduits corresponding to the injectivity level of low-permeable well strata 20, 21, which leads to equipping the cluster pump station 2 with a high pressure pump 3 of the central nervous system 63-1400 type, as well as at least three fittings at water lines 10, 12, 13 connecting the well pump station 2 with injection wells 14, 15, 16, 17, 18, 19 with lower injection pressure (in comparison with wells 20, 21) and those that opened the strata with high second permeability.

The table shows the comparative indicators of the known (prototype) and the proposed system for maintaining reservoir pressure of an oil field.

Table
Comparative indicators of the known and proposed object device Indicator Values with known (prototype) and proposed systems famous proposed Water injection, thousand m ³ / year 540.2 540.2 The cost of the equipment used, thousand rubles: 1960.6 1865.0 - pump unit, central nervous system 63-1400 1600,0 - pump unit, central nervous system 63-1100 1250.0 - submersible centrifugal pump UETSN 160-1450 350,0 - water conduit L = 75 m, D = 89 × 7 mm 144.8 - gate valve with stopping nozzles, 1 pc. 120,2 - valve with probing nozzles, 3 pcs. 360.6 Re-equipment of a high-watering well into a water well and equipping it with a submersible centrifugal pump ESP 160-1450 650,0 Specific frequency of gusts in waterways, pcs / km 0,031 0.013 Costs to eliminate gusts, thousand rubles / year 2200,2 922.7 Energy costs for water injection, kW · h / year 3908.7 3272,7 Energy costs for water injection, thousand rubles / year 6371,2 5334.5

Thus, at a lower cost of equipment - 1865 thousand rubles in the proposed reservoir pressure maintenance system (1960.6 thousand rubles - in the well-known reservoir pressure maintenance system), the energy consumption for pumping water in the proposed reservoir pressure maintenance system is 19.4% and the cost of eliminating gusts is 2.4 times lower than the well-known reservoir pressure maintenance system.

The technical and economic efficiency of the proposed system for maintaining the reservoir pressure of an oil field is achieved by optimizing the technological scheme for maintaining the reservoir pressure of an oil field by replacing the existing pumping equipment of cluster pumping stations with pumps with lower pressure, as well as the additional use of formation water for injection into reservoirs.

The use of this invention in the oil industry allows to reduce costs per unit (1 m ³ ) of pumped process water and, ultimately, reduce the cost of a unit of oil produced (1 t) due to:

- pressure reduction in water conduits connected to highly-responsive wells, due to this the use of cheaper pumping units with lower head at cluster pumping stations;

- reducing the rate of decline in the dynamic productivity of low-permeability wells and / or wells with higher requirements for water quality depending on reservoir properties of the reservoirs by pumping higher quality water from water wells with high pressure pumps;

- increase the service life and reduce the likelihood of gusts in water conduits connected to highly-responsive wells, due to a decrease in working pressure.

Thus, the use of this invention will reduce material costs for the construction, maintenance and repair of water injection systems.

Claims (1)

A system for maintaining reservoir pressure, including a cluster pump station with a high-pressure pump with a discharge conduit, connected by water conduits to injection wells operating at different injection pressures and / or opened reservoirs with different reservoir properties, characterized in that the system is additionally equipped with water wells with high-pressure pumps each connected to water conduits leading to injection wells of higher discharge pressure and / or with higher requirements and to the quality of water depending on the reservoir properties of the formations, while these water conduits are connected to the discharge conduit of the cluster pumping station through an adjustable hydraulic resistance.