RU2351748C2 - Method of programmed regulated maintaining reservoir pressure at oil extracting - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: suggested invention refers to oil producing industry. The method of programmed regulated maintaining of reservoir pressure for intensification of oil withdrawal includes water supply from a pump via a collector and a row of automated shut-off and regulating facilities-regulators to high pressure of liquid with mechanical impurities; the said regulators consist of a separating connection chamber and an output collection chamber. The chambers are united between them with electromagnetic valves regulated from a controller by feedback with electromagnetic flow meter. The separating connecting chamber is formed with an input connecting flange and a connecting case with seats for ceramic bushings. The output collection chamber is formed with a flange pass-through case and an output connecting flange. The multi-channel multi-shut-off regulating facility installed before a pressure well creates a row of controlled dynamic conditions of liquid flow both interrupted from short to durational stops of flow with various amplitude values and continuous flow with preset nominal-core value of amplitude from constantly open part of gates and fluctuating in the mode add-diminish by means of opening, shutting-off or simultaneous operation of the other part of gates regulated by individual programs from the controller; in its turn this creates a row of controlled gradients of flow rate in non-uniform oil reservoirs and changes oil extraction from weakly permeable layers.

EFFECT: increased oil withdrawal from reservoirs.

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Description

The proposal relates to the oil industry, namely to hydrodynamic methods of increasing oil recovery and methods of pumping water into an injection well. The method of software-controlled reservoir pressure maintenance includes the water supply from the pump (KNS cluster pump station) through the collector (BNG pressure distribution comb unit) and a number of automated fluid flow controllers installed on each water conduit connected to the injection wells. Regulators are controlled from the controller (including the upper level).

Known methods of maintaining reservoir pressure, including a pump (or SPS), a distribution manifold with valves for supplying and shutting off fluid to the wells [1]. This equipment scheme allows only the distribution of fluid from wells from one pump and cyclic water flooding (shut-off wells for a long period, changing the direction of fluid flow).

Known wellhead set with a regulator [2], containing choke valves, an angle choke, a flow meter mounted on wellhead discharge valves. The disadvantages of this design are: the inability to use multiple nozzles at the same time to achieve a significant nominal pass of the valve (for example, DN 30, 40 mm); frequent closure of the water line when changing nozzles (which leads to water hammer on a liquid column in a well 1800 meters high), manual control mode (the design of the disk with revolving nozzles does not allow the use of electric, pneumatic, or hydraulic drives).

The aim of the invention is to increase oil recovery by the oscillatory effects of fluid on the reservoir. Vibrational effects are achieved by a frequent change in the flow rate of the fluid supplied to the reservoir using automated fluid flow controllers [3] (Fig. 1) for a single well and using an automated dividing-regulating pump unit [4] (Fig. 2) for several wells (for a well cluster).

An automated fluid flow regulator (or an automated locking and regulating device) [5] contains: an inlet flange 1 forming a dividing chamber with a choke flange body 3. The housing 3 is connected to the flanged passage housing 4 through solenoid valves 12 (or) ball valves 5. To the housing 4 by pins 9 through the sealing ring 7 is connected an output flange 2, which together forms a combined output chamber. In the housing 3 around the circumference are slots for installing (removing) ceramic fittings 6 with calibrated holes from 2 to 20 mm (or the desired set of holes). Ceramic fittings 6 are installed in slots with a rubber sealing ring, and their holes are protected from contamination by a filter - mesh. The fittings and filters are fixed in the sockets. The electromagnetic valves for control are connected to the controller 11 with feedback from the electromagnetic flowmeter 13. The electromagnetic valves 12 or ball valves 5 are connected to the housings 3, 4 using a nipple 15 and a nut 16 (or coupling) to improve the manufacturing process and maintainability of the device.

The locking-regulating device can be controlled from a top-level controller, while ultrasonic or electromagnetic flowmeters included in the comb block or pump station can be used as a flowmeter.

An automated shut-off and control device works as follows: in accordance with the technological schedule of modes (controller program), the opening of all valves provides a quick filling of the control object, for example water pipes, to the formation; the overlap of all valves ensures that the device operates as “closed”, and the combination of the number of open-closed valves allows you to adjust the fluid flow in time from a split second or more; flow rate from DN 0 to DN equal to the total area of the nozzle openings (DN - nominal diameter). The number of possible combinations of the total cross-section is several tens, and the discreteness of regulation in time and volume (flow) allows for program-controlled maintenance of reservoir pressure during oil production.

For several wells, an automated dividing-regulating pumping unit (ARRNU) is used (Fig. 2), which contains: outlet (from pumps) conduits 1, 2, 3, which perform the function of a dividing collector; automated flow controllers with flow meters and controllers 4, 5, 6, 7, 8, 9 (5); outgoing pressure conduits 10, 11, 12, 13, 14, 15 (whiskers); pumping units 16, 17 with a control and monitoring system and valves 18, 19.

The installation works as follows: the pump unit 16 or 17 pumps liquid under high pressure (160-210 kgf / cm ² ) into the water conduits and collector (3), where it (water) is distributed among the flow regulators (4, 5, 6, 7, 8, 9), and then through water conduits (10, 11, 12, 13, 14, 15) it enters the field pipelines to the injection wells. Flow regulators (4, 5, 6, 7, 8, 9) provide fluid control over time from several seconds or more, at a flow rate from DN 0 to DN equal to the total cross-sectional area of the nozzles with the valves open (within DN = 0 ÷ 65 mm ) Each controller is controlled by a controller with feedback from the flow meter. Gate valves and a drainage system for draining the liquid during the repair of individual units are used from the pump part of the installation and are not shown in the drawing.

The intensification of oil production is achieved by controlled non-stationary injection of fluid into the reservoir, which can be provided by a shut-off and control device containing a dividing choke chamber and a collection chamber interconnected by two ball valves and two electromagnetic valves. Various options for such an injection are shown in graphs 3 ÷ 6 (Figs. 5-8). Charts 1 and 2 (Figs. 3 and 4) respectively show a stationary method for pumping liquid and cyclic flooding with a constant flow rate.

Schedule 3 - adjustable injection, in which two ball valves provide the nominal (rod) value of the fluid flow rate, and one valve operating in the "closed - open" mode provides time control from a fraction of a minute or more and in amplitude ΔQ ₃ (to increase total flow area of fittings).

Schedule 4 - adjustable injection to a decrease from the nominal value when two ball valves and one valve operating in the "closed - open" mode are operating - the oscillation amplitude is ΔQ ₄ .

Schedule 5 - synchronous adjustable injection, in which two ball valves and two valves operate simultaneously - the oscillation amplitude is ΔQ ₃ + ΔQ ₄ .

Schedule 6 - cyclic flooding with controlled fluid flow.

Literature

1. Sharbatova I.N., Surguchev N.P. Cyclic effects on heterogeneous formations, M. 1997, pp. 112-115.

2. Wellhead sets TU 3665-003-4965 2808-2001, LLC Tekhnovek RF, Udmurtia, Votkinsk.

3. Utility Model Patent No. 43636, 2004, Automated fluid flow regulator.

4. Patent for utility model No. 49924, 2005, Automated dividing-regulating pump unit.

5. Application for patent No. 2006128645 of 08/07/2006, an Automated locking and regulating device for pressure up to 320 kgf / cm ² .

Claims (1)

A method of software-controlled maintenance of reservoir pressure to intensify oil production, comprising supplying water from a pump through a collector and a number of automated shut-off and regulating devices-regulators for high fluid pressure with mechanical impurities, containing a dividing choke chamber and an outlet collecting chamber, interconnected by electromagnetic valves, controlled from a controller with feedback with an electromagnetic flowmeter, characterized in that the choke dividing chamber is formed by one connecting flange and a choke case with sockets for ceramic bushings, and the output assembly chamber is formed by a flange through-case and an output connecting flange, while a multi-channel multi-gate shut-off and control device installed in front of the injection well creates a number of controlled dynamic states of the fluid flow: as intermittent short-term to long-term stop of the flow with different values of the amplitude, and continuous with a preset nominal rod value the amplitude from the constantly open part of the gates and changing in add-on mode due to the opening, closing or simultaneous operation of the other part of the gates according to individual programs from the controller, which, in turn, creates a number of controlled gradients of the flow rate in heterogeneous oil reservoirs, changing the oil recovery from low permeability layers.

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