RU2690465C1 - Method for preparation and transportation of products of well production at mature oil deposits and system of implementation - Google Patents

Abstract

FIELD: mining.SUBSTANCE: invention relates to a method of preparing and transporting products of well production at mature oil deposits and a system for realizing (maintaining formation pressure) of oil industry and can be used in oil fields using a pressure formation system (maintenance of formation pressure). Method for preparation and transportation of well production products at mature oil fields involves evaluation by parameters of well production parameters and preliminary preparation with separation of production by production well into phases. Thereafter, a combined decentralized stream of well production is formed with industrially significant residual oil content at volume of flow V0 = F {f [(V1 + V2 +…+ Vn), Pd], Pd =ϕ(Os)} from cluster groups of wells with possibility of mobile variation and flow regrouping from wells. Then, well production products are separately transported from cluster groups by low-pressure streams from wells via pipelines to decentralized complex preparation of combined flow of well production products. Decentralized complex preparation includes degassing and subsequent separation of emulsion into oil and return water, which is accumulated with subsequent controlled return to cluster groups for recycling by low pressure pipelines, where (V0) is the merged flow maximum volume, m/day; (V1, V2, …, Vn) are the volumes of well cluster production K1, K2…Kn wells, m/day; (Pd) is limiting pressure in systems of combined and borehole flows, MPa; (Os) - reliability of preparation and transportation as ratio of number of failures per year to number of producing decentralized wells. System for preparation and transportation of products of well production at mature oil deposits includes measuring devices of parameters of well extraction, preliminary preparation device and pipelines. System is implemented in the form of decentralized complex of mobile devices and equipment, combined into system by flexible anticorrosion pipelines of low pressure for transportation of products of well production with possibility of rapid variation and regrouping of pipeline system of flows arranged on selected site in close proximity to cluster groups of producers, injection and absorbing wells. System includes mobile individual pumping units into injection and absorbing wells connected to decentralized mobile complex, decentralized complex preparation includes gas separator, separator for gas, oil and water, separation quality assembly, accumulator in the form of reservoir and device for further controlled distribution of produced water, which provides transportation to cluster groups for PPE system and recycling.EFFECT: technical result of group of inventions is enabling minimized transportation, optimization of recycling of produced water, possibility of reducing pressure during transportation of product, possibility of use for transportation of water, oil-associated gas and oil of low-pressure pipelines with possibility of efficient assembly-dismantling and relocation of decentralized systems with high corrosion resistance, possibility of rapid control of pressures and water flow rates during pumping and provision of possibility to control water balance between multifuel boilers.9 cl, 1 dwg

Description

1. Field of technology

The invention relates to the oil industry and can find application in the oil fields using the PPD system.

2. Prior art.

For the majority of oil companies, one of the current ones, is the problem associated with the development of residual reserves in fields that are at a late stage of development.

Oil production at oil fields in the late stages of development using the RPM system is accompanied by an increase in volumes of produced water, a change in the water-oil factor and a sharp increase in the share of costs for collecting and transporting well fluid, preparing oil and disposing of produced water. These main costs increase the cost of oil production with constant negative dynamics.

The location of the operating stock of producing and injection wells in mature oil fields is mosaic in size and often does not coincide with the distribution of residual reserves and the associated need to reanimate existing infrastructure due to critical wear of existing field networks to maintain an efficient development system, which further complicates achieving economically viable oil production.

Organizational-technological and economic problems are superimposed on all the unresolved technical problems: low, and in most cases, negative profitability of oil production; lack of motivation in financing geological and technical measures (GTM) due to their low efficiency and high risks.

In the complex, these problems cannot be solved today only within the framework of the centralized field pipelines system without a fundamental revision of the collection and transportation system using field pipelines.

One of the pressing problems is also the problem of solving a technical problem involving the residual oil reserves in active development due to the commissioning of mothballed and inactive wells.

There is a method and device implementation used in oil production, where at large fluid flows divide the production of wells into phases, the transport is in the form of pipelines without transporting water over long distances, carry out preliminary processing, collection of production of wells, gas separation, separation of oil and water, cleaning water and its disposal. (Patent of the Russian Federation No. 2230594, 2004, IPC B01D 17/00).

The method and device do not provide the ability to control the injection of return water when changing the water-oil factor of individual wells and groups of wells, the movement of the stock of existing wells.

The disadvantages of the installation and the method implemented by it include the fact that it is intended only for preliminary discharge of water, and does not reflect the other requirements for the preparation and separate transportation process that can be provided at the oil field.

The disadvantage of the installation is its structural complexity, the use of a large number of devices, separators and high-pressure pumps, and the need for round-the-clock staff service and, accordingly, low reliability. The installation includes a device for preliminary separation of well production into phases with lines, their outlets into oil and water separators, buffer tanks for oil and water with pumps and a heater. The installation further comprises a gas separator installed on the line of water drainage from the apparatus for preliminary separation of production of wells into phases, made in the form of an inclined pipe with a water supply line above the liquid level and connected to a water separator, while the said device is made in the form of an inclined pipeline with supply lines wells, water output, oil and gas, oil separator - in the form of a tank with partitions, water separator - in the form of a sump with a hydrophobic layer, and the heater is installed on the line twater oil from the oil buffer tank to supply heated oil well production inlet line and the input line of the oil in the oil separator, the gas from the output line of the installation devices are connected to a common pipeline for supplying the gas as fuel to the preheater

Known mobile complex for the processing of liquid petroleum products, including mobile devices with the ability to reinstall them for the implementation of refining processes. (RF PM № 48805, 2004, IPC B01D 17/00).

The disadvantage of this method is that it cannot be used for the preparation and transportation of well fluid.

It is also known, taken by the applicant for the closest, both in terms of the method and in the part of the device, technical solution (RF Patent for utility model No. 138431, B01D 17/00 (2006)) “Installation for preliminary dumping ...”, in which preliminary preparation - separation of well production into phases with lines for their withdrawal, installed in close proximity to the producing and absorbing wells, the installation is equipped with measuring devices.

The disadvantage of the method and device pre-separation of well production, installed in the immediate vicinity of the group metering unit is that the device of high pressure is selected as a device for preliminary separation of well production, while the installation is equipped with a high pressure pipeline and a pipeline to drain the oil and gas mixture to the group header metering unit for the further transportation of products, a valve for regulating the volume of discharged water connected to the device High pressure using a pipeline to divert water into an absorption well, a media level indicator, an electrical contact pressure gauge to transmit a signal to the valve actuator.

The disadvantage of the installation is that for separation and preliminary discharge of produced water use high-pressure devices in the form of thick-walled high-pressure tanks, in which the redistribution of phases into water, oil and the release of water as a free phase occurs due to gravity forces and hydrocyclone method. The high-pressure devices and the well are connected by a pipeline, through which the well production under elevated pressure enters the device, depending on the head of the production well installation and taking into account the pressure necessary to ensure the required injectivity of the absorption well intended for utilization of associated produced water.

In addition, such a system does not allow to quickly regulate the costs of pumping water into the wells with varying injection capacity and production wells, and the presence of high-pressure pipelines requires special measures to organize the work.

3. The invention

3.1. Setting a technical problem

The technical task is to optimize oil production with a high water content of wells at the field, increase the production of residual reserves at fields that are at a late stage of development, reduce energy costs and increase safety, environmental friendliness and reliability of the collection and transportation system using field pipelines.

3.2. The result of solving a technical problem

The solution of the technical problem is implemented by replacing the high-pressure centralized method of collecting and transporting low-pressure decentralized mobile preparation and transportation systems with a very short (up to 100 m) by high-pressure pipelines (up to 20 MPa) implementing decentralization based on collecting well wells of individual wells grouped into (mobile technological clusters - MTC) by relative balance of production of produced water, demand for water injection volumes For PPD + technical readiness for disposal of residual water. In this case, the MTC can be interconnected to maintain the optimal balance of movement of produced water and operational regulation of the operating modes of the system and its components.

Solved the complex problem of minimized transportation and optimization of utilization of produced water. One of the solved technical problems is the possibility of reducing the pressure during transportation of products. The possibility of using for transportation of water, gas and oil low pressure pipelines (TPSD) with the possibility of rapid installation - dismantling and relocation of decentralized systems with high resistance to corrosion, ensuring the ability to quickly control pressures and flow rates of water during injection and ensure prompt adjustment of water balance between the MTC that, in combination with the mobility of equipment, can significantly reduce the cost of the most significant items characteristic of the field at the late stage of development, namely: the cost of owning the RPM system, the cost of eliminating gusts in the oil-gathering and water pipelines, reducing electricity consumption, fines for environmental pollution, extending the period of economically viable operation, especially extremely water-flooded (more than 95% of water in composition of well fluid) deposits.

4.1. List of drawings

FIG. Figure 1 presents the “Decentralized mobile node of the system for collecting, preparing and transporting downhole products in mature oil fields”, which represents a system of traffic flows and devices on the example of cluster number 4-k (1) and decentralized mobile node (7) of the complex for preparation and distribution of products production, where 1 is the system of traffic flows of the cluster node (for example, the K-4 cluster node), 2 is a mobile individual cluster injection unit forcing (MIUZ-N), 3 is a mobile individual cluster node Achki absorbing (MIUZ-P), 4 - production wells of the K-4 cluster node: 4 (1) - production well No. 1 of the K-4 cluster node; 4 (n) - production well No. (n) of the K-4 cluster node, 4 (s) - production well № (s) of the K4 cluster node, 5 - injection well, 6 - absorbing well, 7 - locally centralized mobile site of preparation and distribution, 8 - collection and complex preparation of locally centralized production volume of the product, 9 - degassing, 10 - separation of the emulsion into water and oil, 11 - gas, 12 - oil, 13 - centralized or local consumption, 14 - water military, 15 - return water accumulation, 16 - regulated distribution of water return, 17 - low pressure fluid stream from a production well, 18 - non-activated activation well with the ability to connect to a mobile locally centralized system, 19 target return flows, 20 - separate measurement of water, oil and gas parameters, 21 - optimized water utilization flows, 22 = (17 + 18 + ...) - decentralized volume flows, 23 - combined flow, s - number of wells on a dedicated hive, n - number of allocated d To activate wells in the bush.

4.2. Features

In contrast to the known method, which involves estimating borehole production parameters, carried out by measurement and preliminary preparation with separation of production by well production into phases, the combined decentralized flow is formed in the method of preparing and transporting downhole products in mature oil fields (22 = (17 + 18 + ...) ) downhole production with industrially significant residual oil content with flow volume V0 = F {f {(V1 + V2 + ... + Vn), Rd], Pd = ϕ (Os)} from the well cluster groups (17, 18), with the possibility of mobile variations and overheating pack up flows from wells, separately transport borehole production products from cluster groups with low pressure streams from wells through pipelines to decentralized complex preparation of the combined stream (23) of the well production product, decentralized complex preparation includes degassing (9) and subsequent separation of the emulsion into oil and return water which is accumulated (15) with the subsequent regulated return to the cluster groups for utilization by pipelines with low pressure streams, during separation t perform additional degassing, where

(V0) - the maximum volume of the combined stream, m ³ per day;

(V1, V2, ..., Vn) - volumes of well production of the K1, K2… Kn well cluster groups, m ³ per day;

(RD) - limiting pressure in the systems of combined and well flows, MPa;

(Os) - reliability of preparation and transportation by the number of failures per year, referred to the number of producing decentralized wells.

In the method, borehole production parameters can be estimated preliminarily by the water content of each production well, with an assessment of the distribution of water content in the wells inside the clusters and inter-well distribution, taking into account that the combined decentralized flow forms a simultaneous direction of the flow from the production wells to the complex preparation significant average oil content in the combined flow of more than 0.8%, wt.

Under the terms of safety and the possibility of saving energy, the allowable pressure Rd in the flow system, it is advisable to take Rd <= 0.1 MPa, and after separation, measure the flow of gas, oil and water, the flow of oil and gas is sent to the main flow or directly to consumption, and transportation if possible, carry out flows with laminar fluid flow through the pipeline.

The system of preparation (8) and transportation of downhole products in mature oil fields, in contrast to the well-known, including measurement devices of well production parameters, preliminary preparation device and pipelines, is designed as a complex of mobile devices and equipment combined into a system of low-pressure flexible anticorrosion pipelines liquid products with the possibility of rapid variation and rearrangement of the pipeline flow system, the system is equipped with centralized mobile complex (7) located on a dedicated site in the immediate vicinity of the cluster groups of producing, injection and absorbing wells, also includes mobile individual injection units to injection wells and mobile individual injection units connected to a decentralized mobile complex transport mobile system low pressure pipelines (19) of the product of extraction and low pressure pipelines of return water for injection and absorption pumping and connected to the pipeline for decentralized complex preparation of the combined well production stream, decentralized complex preparation includes a separator (10) for gas, oil and water, a storage accumulator (14) in the form of a tank and a device for subsequent controlled distribution providing feedback to the return water cluster groups for disposal (21).

In the system, the flexible pipeline can be made with locking connections for quick installation - dismantling and with the possibility of laying, ensuring laminar transport of fluid, and the maximum allowable pressure Рд flows in the pipeline system to accept Рд <= 0.1 MPa.

One of the options for measuring in the form of separate units for measuring gas, oil and water, local territorial pipelines for oil and gas flows are connected to main pipelines or directly to consumption, and areas of plugged wells or wells removed from the pool of bushes are used as a dedicated site.

4.3. Description of the essence of the method

The exploitation of fields that are at a late stage of development shows that a significant part of the costs is associated with maintaining the existing system of field pipelines for the collection and maintenance of reservoir pressure and the cost of electricity used to prepare and transport the well fluid and utilize the produced water. At the same time, with an increase in the water cut, the concentration of its (oil) in the well fluid with small amounts of oil decreases exponentially.

The essence of the proposed solution is to create and organize a decentralized preparation system that provides an increase in the average mass concentration of oil (by mass) in the mixture, which provides a higher degree of separation into phases.

In the method, according to the estimation of parameters of well production from separate streams from wells, a decentralized docking stream combining streams from wells with different concentrations of oil is formed by combining streams. Such a combination averages the concentration of oil and levels the flow with a very low content.

5. An example of a specific implementation (implementation of the solution)

The implementation of the proposed decentralized collection and transportation system is envisaged on the basis of a set of equipment, technical and technological solutions developed by L-Petro. Designing a decentralized mobile site for collecting, preparing and distributing products (86) on the basis of a mobile platform and a management station is carried out individually, with reference to a specific field, the design of which is developed by L-Petro and provides: degassing, separation of oil-water emulsions and quantitative and qualitative measurement of products coming from a group of operating wells located on bushes connected to the MTC.

As a gas separator, mass-produced products are used depending on the gas factor and the volume of associated gas, for example: SGV-7 produced by NPO Vertex.

Mobile individual download nodes (MIUZ-N (2) and MIUZ-P) (3) were developed by L-Petro and manufactured by L-Start.

The use of Polycord-Flex flexible polymer-metal pipes according to TU 2248-006-54031385-12 is supposed to be used as high-pressure pipelines in the collection system for products from the well pads to be combined (TU 2248-006-54031385-12), in the water injection system from MIUZ according to TU 2224-00721171125- 00 produced by Remmash-Service.

The use of HDPE PE100 / SDR11 HDPE pipes manufactured according to GOST 18599-2001 and TU 2248-016-40270293 is envisaged as low-pressure pipelines for distribution and transportation, separated at the node (8b) of oil (12), gas (11) and water (19). -2002 ("Trubopolymer").

6. The results of calculations performed for the N-skiy field in Western Siberia, confirming the effect of the application of the proposed technical solution:

- The current CND will be mothballed.

- Of the 78 kilometers of pipelines with an average pressure of 115 atmospheres: 80% will be decommissioned and only 20% (mostly of small diameter) will be converted to pressure up to 10 atmospheres.

- The technological parameters (P, V) necessary for the development system are implemented at the injection points via MIUZs, as well as the possibility of implementing an automated maintenance of the injection mode other than constant, which directly affects the pre-extraction of residual oil reserves

“By reducing the pressure, it is assumed that the life of the water lines will increase and the risks of accidents will significantly decrease.”

- Existing large-diameter oil gathering networks (over 219 mm) will be decommissioned.

- New pipelines from HDPE are guaranteed against corrosion for up to 50 years and do not require the cost of condition monitoring.

- The level of energy consumption with comparable volumes of production of well fluid will be reduced by no less than 40%.

- Specific energy consumption per 1 m ^{3 of} water injection into the reservoir will decrease by more than 2

times.

- The specific energy consumption per well fluid recovery will decrease by at least 20%.

- The cost of restoring emergency pipelines and the payment of fines for the environment for the entire period before the development of reserves (about 30 years) are practically excluded.

- Four MTCs will ensure the infrastructure needs of the oil industry in the current volumes and location of the existing well stock.

- The number of MTC can be increased only by two units in the implementation of the pilot plan for the reengineering of a development project due to their mobility and work at growth points.

Claims (13)

1. A method of preparing and transporting downhole products in mature oil fields, including evaluating the parameters of well production and preliminary preparation with separation of production by well production into phases, characterized in that they form a combined decentralized well production stream with an industrial-significant residual oil content in the volume flow V0 = F {f [(V1 + V2 + ... + Vn), RD], Rd = ϕ (Os)} from well groups with the possibility of mobile variation and rearrangement of the flows from the wells, separately porting downhole products from cluster groups by low pressure streams from wells through pipelines to decentralized complex preparation of the combined well production stream, decentralized complex preparation includes degassing and subsequent separation of the emulsion into oil and return water, which is accumulated and subsequently regulated back to the cluster groups for disposal through low pressure pipelines where (V0) - the maximum volume of the combined stream, m ³ / day; (V1, V2, ..., Vn) - borehole production volumes of well clusters K1, K2 ... Kn, m ³ / day; (RD) - limiting pressure in the systems of combined and well flows, MPa; (Os) - reliability of preparation and transportation as the ratio of the number of failures per year to the number of producing decentralized wells. 2. The method according to p. 1, characterized in that the estimation of parameters of well production is carried out previously on the water content in each production well with an assessment of the distribution of volumes of produced water along the wells inside the bushes and between the beds, with which the combined decentralized flow is formed by the direction of flow production wells for comprehensive training. 3. The method according to p. 1, characterized in that the allowable pressure RD in the flow system is set according to the condition of guaranteed reliability of safety at a fixed value for the decentralized system Rd <= 0.1 MPa. 4. The method according to p. 1, characterized in that after separation measure the flow of gas, oil and water, the flow of oil and gas separately sent to the main flow or directly to consumption. 5. The method according to p. 1, characterized in that the transportation after separation of the three-phase flow is carried out in separate streams through pipelines. 6. System for preparation and transportation of downhole products in mature oil fields, including measuring devices for downhole parameters, preliminary preparation device and pipelines, characterized in that the system is designed as a decentralized complex of mobile devices and equipment combined into a system with flexible anti-corrosion low-pressure pipelines for transportation of downhole products with the possibility of rapid variation and rearrangement of pipelines oh flow system located on a dedicated site in the immediate vicinity of the cluster groups producing, injection and absorbing wells, and includes mobile individual injection sites in injection and absorption wells associated with a decentralized mobile complex, decentralized complex preparation includes a gas separator, a separator for gas, oil and water, a separation quality unit, a storage unit in the form of a tank, and a device for the subsequent controlled distribution of produced water, bespechivaet transport system Shrub group for PPD and disposal. 7. The system of claim. 6, characterized in that the flexible pipeline is made with locking or flange connections for quick installation and dismantling and with the possibility of laying, providing laminar transport of fluid. 8. The system of claim. 6, characterized in that the maximum allowable pressure RD flows in the piping system set Rd <= 0.1 MPa. 9. The system of claim. 6, characterized in that the well pad sites of non-performing wells or other sites of the old infrastructure are used as a dedicated site.

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