RU2808739C1 - In-line vortex-type separator with control system based on neural network and mobile pre-water discharge unit - Google Patents

Abstract

FIELD: oil and gas production industry.

SUBSTANCE: invention can be used as a separation device in preliminary water discharge installations, oil treatment installations, and gas treatment installations. An in-line vortex-type separator with a control system based on a neural network contains a separating vortex chamber, which in the inlet part contains a tangentially located inlet pipe for the input flow, an axially located outlet pipe for the light phase, and on the other side has an outlet pipe for the heavy phase. Control electric valves are installed on both outlet piping lines of the separation vortex chamber. Coriolis flow meters, pressure sensors, temperature sensors and shut-off and control valves are connected to the hydraulic control circuit for in-pipe separation, and the dynamic process of in-pipe vortex separation is controlled by an automated system with an autonomous process mode adjustment module based on an artificial neural network with an intelligent controller based on a three-layer perceptron with a network predictive controller of the PID algorithm for processing high-frequency measurements of the residual water cut of the in-line moisture meter, with adjustable parameters of the control system for the electric drives of the valves of the in-line vortex-type separator. The mobile preliminary water discharge installation contains a pipe vortex sand separator, a pipe vortex gas separator, an in-pipe vortex separator with a control system based on a neural network, a three-phase separator unit, a water settling unit, a reagent dosing unit, connected in series by a pipeline system. The mobile installation is made in form of a single monoblock with a two-tier arrangement of technological blocks placed in frames with the dimensions of 40- and 20-foot cargo containers.

EFFECT: ensuring the process of effective separation of water-oil emulsion with an automatic control system for electric drives of regulatory elements based on an artificial neural network.

2 cl, 2 dwg

Description

The invention relates to the oil and gas production industry and can be used as a separation device in preliminary water discharge installations, oil treatment installations, and gas treatment installations.

To carry out separation in field practice, capacitive equipment is used in the form of vessels operating under pressure, having the shape of a horizontally elongated cylindrical volume.

In modern conditions, in actively developing mobile configurations, there is a need to carry out the separation of water-oil-gas mixtures in devices that are more compact, compared to traditional metal-intensive gravity separators, in a faster mode, using the energy of the fluid flow in the pipe. For this purpose, the technology of in-pipe separation of multiphase flows in the field of centrifugal forces is used. The rotational movement of water-oil-gas mixtures in vortex separation devices can be carried out in two types of pipe apparatus: by supplying the flow to the blades of a swirler located axially to the axis of the pipeline and by supplying the flow to the separation pipe chamber through a tangentially located inlet pipe.

The experience and developments of in-line separation in projects of underwater production complexes of the FMC and Cameron companies have proven the practical effectiveness of such systems (patent 0002597113 Two-section flow separator, FMS SEPARATION SYSTEMS, BV (NL). In-line separators are also widely introducing vortex separation of two-phase flows (liquid/gas) for separation of hydrocarbon condensate and water from natural or associated petroleum gas (as an example, patent RU 2747403 C1 In-line separator, AEROGAZ LLC).

The separation of the water-oil emulsion in the in-pipe centrifugal flow is carried out due to the difference in the densities of the two liquid components of the mixture. Under the influence of turbulence in a turbulently swirling axial flow, mass transfer processes occur in the area of the central axis of the vortex:

- direct ordering of the Brownian motion of the liquid in the vortex bundle, the chaotic vectors of the thermal motion of the molecules are aligned strictly parallel to the axis of rotation;

- centrifugal forces create a vacuum zone right in the center with an anomalous acceleration of the flow and an increase in the kinetic energy of the liquid in the central axis of the vortex;

- a rope of liquid with a lower density is formed in the central zone, the direction of the central flow changes to the opposite to the vortex movement of the liquid with a higher density in the wall zone of the pipe, and a separation process occurs.

A device is known for the destruction of water-oil emulsion during transportation through a pipeline (Patent RU2600742C1, IPC C10G 33/06, B01D 17/04, publ. 10.27.2016), including a pipeline in front of the longitudinal partition in the direction of the oil-water emulsion flow is equipped with a cone tapering in the direction of the oil-water emulsion flow in the ratio of the areas of the cone bases of 2:1 in the direction of the oil-water emulsion flow, while inside the cone a screw made in the form of a spiral plate is concentrically installed, while the flow area part of the auger decreases in the axial direction from inlet to outlet, and the angle of inclination of the auger blades at the outlet is less than 90°, and at the outlet of the cone, an annular disk is installed between the auger and the cone, forming an annular chamber with the cone, hydraulically communicating through a radial hole made in the cone with a discharge of heavy fractions embedded in the pipeline, and the area of the flow part between the screw and the annular disk is less than the area of the flow part at the exit of the screw.

The disadvantages of this device are:

- low efficiency of destruction of water-oil emulsion, due to weak swirling of the flow;

- there is no possibility of use in devices with high flow rates and high water content of the emulsion.

A known installation and method for vortex cracking of oil and petroleum products (patent RU 2305699 C1, IPC C10G 9/00, B01F 11/00, published 09/10/2007) The fundamental element taking part in vortex cracking of oil is a vortex dividing device containing a vortex tube, a tangential inlet nozzle, a volute and a choke. Oil under pressure is supplied through a tangential nozzle into a vortex tube, inside which an intense circular motion is created. At the exit from the tangential nozzle, the oil flow forms an external vortex, which develops to a certain radius and moves along the axis of the pipe to the throttle installed at the end of the vortex pipe. The external vortex is resistant to internal friction forces and is not destroyed by them. The vortex can be destroyed only at its radial boundaries due to friction against the walls and interaction with the axial elements. The intensity of its swirl decreases due to a decrease in peripheral speeds when the vortex moves along the pipe to the throttle, the radial gradient of static pressure in the vortex flow of oil decreases, and the vortex that gets into the paraxial region of the oil changes its original direction of axial movement to the opposite and moves towards the nozzle section. During the transition to the paraxial region, oil elements are intensively turbulized. High turbulent viscosity forces the axial flow of oil to rotate according to the law of a rigid body. The reverse axial flow, as it moves towards the swirler, is swirled by a more intense external vortex. In addition to the transfer of kinetic energy of rotation from the external to the forced reverse vortex, intense turbulent heat exchange occurs between them at a high static pressure gradient normal to the average speed of the oil flow.

The disadvantage is the lack of a control system for the flow of forward and reverse vortices at the outlet pipes of the dividing device.

An in-line separator for separating oil-water mixtures is known (patent RU 2 456 052 C2, IPC B01D 17/038, published on July 20, 2012), relating to the separation of the mixture into an oil-rich phase and a water-rich phase using a linearly arranged separating device and the method includes:

- installation of a pipe for supplying an oil-water mixture,

- installation of an elongated tubular separating device, including in series: (inlet, vortex-generating chamber, central separating chamber and outlet),

- installation of an outlet pipe for the oil-enriched phase and an outlet pipe for the water-enriched phase,

- the inlet of the separating device is connected via a fluid medium to a pipe for supplying the water-oil mixture and a vortex-generating chamber,

- the central separation chamber is fluidly connected to the vortex-generating chamber and the separator outlet,

- the outlet is additionally fluidly connected to the outlet pipe for

oil-enriched phase and an outlet pipe for the water-enriched phase,

The vortex-generating chamber has a vortex-generating element.

The disadvantage is that with all the variety of described design options for vortex separation devices and their structural elements, there is no possibility of automated control of pressure reducing valves installed on the outlet pipe for the oil-enriched phase and the outlet pipe for the water-enriched phase when the physical properties of the incoming emulsion change in process of field exploitation.

The closest analogue in technical essence is a hydrocyclone-type device for separating emulsions (patent RU 194860 U1, В01D 17/0217; B04C 5/04, published 12/25/2019) containing at one end a head section configured to supply the emulsion into the working cavity through at least four tangential inlet holes evenly distributed around the circumference in the cylindrical part of the head section. The ratio of the diameter of the inlet holes to the diameter of the working cavity in the cylindrical part of the head section ranges from 1/10 to 3/50 inclusive. Also in the head section there is an output channel for the less dense component of the emulsion. At the second end the device has a cylindrical section and an outlet for the denser component of the emulsion. The cross-sectional area of the device decreases from one end to the other.

The disadvantages of the device are:

- limited functionality, lack of devices for regulating the separation process from the changing properties of the incoming mixture;

- the complexity of manufacturing the conical section of the separation chamber, small dimensions of the internal diameters of the inlet and outlet with a long length;

- low productivity.

The purpose of the present invention is to create a device and installation that ensures the process of effective separation of water-oil emulsion with an automatic control system for electric drives of regulatory elements based on an artificial neural network,

This goal is achieved by creating an in-line vortex-type separator (hereinafter referred to as VTS), which includes a separation vortex chamber, an in-line moisture meter, control electric valves, control and measuring instruments and sensors.

A distinctive feature of the proposed device is a separation vortex chamber, which is a piece of pipe of calculated length, in contrast to existing analogues, hydrocyclone type oil separators, which have a separation chamber with an internal surface of a variable section of a conical shape.

The criteria for choosing the optimal size of the separation vortex chamber are the input flow parameters: productivity, water cut, temperature, well fluid density. Based on these parameters, using computational fluid dynamics (CFD) methods, we simulated the turbulent flow of an oil-water emulsion in a closed pipe space under the influence of centrifugal forces created by a hydrocyclone swirler located in the inlet element of the chamber in which the nozzles are located: the inlet flow input nozzle located tangentially on the shell pipe chamber and a light phase (oil) outlet pipe located inside the inlet element axially to the axis of the vortex chamber. On the opposite side of the chamber there is an outlet pipe for the heavy phase (formed water). An in-line moisture meter is mounted on the line of the light phase outlet pipe. The operating principle of a flow moisture meter is based on measuring the speed of propagation of an electromagnetic signal in media with different dielectric constants. Electric control valves are installed on both output lines of the separation chamber piping, which maintain the balance of hydraulic resistance inside the chamber. The hydraulic control circuit for in-line separation also includes Coriolis flow meters, pressure and temperature sensors, and shut-off and control valves.

To control the dynamic process of in-pipe vortex separation, an automated system has been developed with a module for autonomous adjustment of the process mode based on an artificial neural network with an intelligent controller based on a three-layer perceptron with a network predictive controller PID algorithm for processing high-frequency measurements of the residual water cut of the in-line moisture meter, with adjustable parameters of the control system for electric valve drives vortex-type in-line separator.

A distinctive feature of such a control system is that the neural network itself finds and sets the ideal ratio of control valves, taking into account the only goal - reducing the water cut of separated oil according to the moisture meter.

This goal is also achieved by the claimed mobile installation for preliminary water discharge (hereinafter - MUPSV), containing a pipe vortex sand separator, a pipe vortex gas separator, an in-pipe vortex-type separator, a three-phase separator unit, a water settling unit, a reagent dosing unit, connected in series by a pipeline system, while The mobile installation is made in the form of a single monoblock, with a two-tier arrangement of technological blocks placed in frames with the dimensions of 40- and 20-foot cargo containers.

The essence of the technical solution is illustrated by drawings: Fig. 1 and Fig. 2

In FIG. 1 shows a schematic diagram of a military-technical vehicle, where:

1 - separation vortex chamber;

2 - input pipe for input flow;

3 - light phase outlet pipe;

4 - heavy phase outlet pipe;

5 - in-line moisture meter;

6 - electric control valve;

7 - Coriolis flow meter;

8 - pressure sensor.

The proposed technical solution for military-technical cooperation works as follows.

The incoming flow of water-oil emulsion enters the separation vortex chamber 1 through the input flow pipe 2, located tangentially on the inlet part of the separation vortex chamber 1. The flow entering the chamber, due to the centrifugal force, acquires a rotational motion, an increased swirl of the flow is created, as a result of which separation begins mixture into two components: formation water, which has a higher density, swirls into the near-wall region of the chamber and, rotating, is directed, along the flow, to the outlet pipe of the heavy phase 4 and oil, with a lower density parameter, swirls and forms a vortex filament in the central zone of the chamber . Under certain conditions of the balance of hydraulic resistance created by two highly sensitive fast-acting electric control valves 6, a zone of return flow of the oil thread is formed to the light phase outlet pipe 3, located in the inlet part of the separation vortex chamber 1. The light phase flow emerging from the vortex chamber 1 enters the in-line flow moisture meter 5, where the value of the residual water content in oil is determined. The input and output parameters of all control and measuring instruments, including pressure sensors 8 and Coriolis flow meters 7, enter the neural network controller (not shown in the diagram), and the separation efficiency is assessed.

The most effective area of application for in-line vortex-type separators, including in-line vortex-type separators, are projects with high flow rates and water cut of well fluid from 3,000 to 20,000 m³ per day in Mobile preliminary water release units.

In fig. Figure 2 shows a schematic diagram of a MUPSV with small-sized devices of in-line vortex separators of the vortex type, on which the following symbols are used:

a) block designations:

9 - Pipe vortex sand separator block

10 - Pipe vortex gas separator block

11 - Vortex-type in-line separator block

12 - Three-phase separator block

13 - Water settling unit

14 - Reagent dosing unit

b) pipeline designations:

15 - well fluid (oil-water-gas mixture)

16 - water-oil emulsion VNE

17 - commercial oil

18 - associated petroleum gas APG (high pressure gas)

19 - formation water

20 - demulsifier

21 - oil-gathering field manifold.

A distinctive feature of the mobile installation for preliminary water discharge based on in-pipe vortex separators is a modular design, made in the form of a single monoblock, with a two-tier arrangement of technological blocks placed in frames with the dimensions of 40- and 20-foot cargo containers. Each technological block is a single set of functional technological equipment that is fully factory-ready. Interblock connections of the pipeline system are made using quick-release connections.

The inventive mobile installation for preliminary water discharge based on in-pipe vortex separators operates as follows: the production of oil wells through the cluster collector 15 enters the Vortex Desander Unit 9, which is a vertical pipe apparatus with a tangential input, in which intensive separation of suspended solids (SSP) from liquid medium. Preliminary separation of high-frequency particles in a small-sized pipe sand separator makes it possible to relieve the separation equipment of the entire cluster installation from the need for regular cleaning of the pipeline network and settling tanks. The well fluid, which is an oil-water-gas mixture, filtered in this dynamic way, is sent to the next stages of preparation. Before entering the main separation equipment, a demulsifier is supplied to pipeline 15 via pipeline 20 from the Reagent Dosing Unit 14. The oil-water-gas mixture, purified from high-frequency particles, enters the Vortex Gas Separator Unit 10, which is a horizontal pipe apparatus in which the vortex flow movement is created by a blade swirler installed axially to the separation axis cameras. During the centrifugal rotational movement of the mixture inside the chamber, two phases with different densities are separated: the liquid phase with a high specific gravity tends to the walls of the chamber, the rotational movement of the gas phase is concentrated in the central part. At the exit from the separation chamber at the end of the separation zone, a device is installed with a pipe in the center for removing the released gas and a swirler in the wall part to calm the flow of the separated liquid phase. The gas outlet pipe is connected to gas pipeline 18. The separated gas is immediately sent to the outlet of the installation into the oil-gathering field manifold 21. The separated liquid phase, representing an oil-water emulsion, is sent through pipeline 16 to the tangential input of the in-line vortex-type separator unit 11, the operating principle of which is discussed above. At the exit from the VTS, the oil flow through pipeline 17 is introduced into the Three-Phase Separator Block 12, where it is additionally dehydrated and then goes into the oil-gathering field collector 21 for transportation along with gas to the oil treatment unit of the oil treatment unit of the central collection point of the central processing plant. The flow of formation water through pipeline 19 enters Water Settlement Unit 13, where it is further purified, and then supplied to the Block Cluster Pumping Station (not shown in the diagram) of the formation pressure maintenance system for injection into the formation.

Distinctive features of the proposed mobile installation for preliminary water discharge based on in-line vortex separators are:

- automated control system with a module for autonomous adjustment of the technological mode based on an artificial neural network with sensors, a network predictive controller of the PID algorithm and high-speed actuators that ensure effective separation in in-line vortex separators;

- preparation of separated water to the required quality for injection back into the formation at remote pads in the immediate vicinity of production and absorption wells;

- dehydration of oil to a state of aggregative stability of the emulsion to prevent the release of free water during its transportation;

- operational accounting of oil, water and associated petroleum gas;

- completely sealed layout corresponding to the design pressure of the collection system and eliminating emissions into the atmosphere, no need for flare and drainage systems;

- autonomous operation without the constant presence of maintenance personnel.

The indicated distinctive features of the proposed VTS with a control system based on a neural network as part of the MUPSV determine its novelty and inventive step in comparison with known methods for separating and preparing well products with high water cut in cluster conditions.

The use of MUPSV equipment with in-pipe vortex separators makes it possible to maximize the efficiency of capital investments by reducing equipment costs and reducing weight and size characteristics. The cost of the project for a mobile preliminary water discharge installation with in-pipe vortex separators is 2.5 times lower than the cost of constructing a capital facility for a tank-type preliminary water discharge installation of similar capacity.

Claims (2)

1. An in-line vortex-type separator with a control system based on a neural network, in which the separation vortex chamber in the inlet part contains a tangentially located inlet pipe for the input flow, an axially located outlet pipe for the light phase, on the other side having an outlet pipe for the heavy phase, characterized in that The emulsion is supplied through one inlet pipe, the separation vortex chamber is a piece of pipe of calculated length, while an in-line moisture meter is mounted on the line of the light phase outlet pipe, control electric valves are installed on both output piping lines of the separation vortex chamber, and the hydraulic control circuit for in-pipe separation Coriolis flow meters, pressure and temperature sensors and shut-off and control valves are connected, and the dynamic process of in-pipe vortex separation is controlled by an automated system with an autonomous process mode adjustment module based on an artificial neural network with an intelligent controller based on a three-layer perceptron with a network predictive controller PID processing algorithm high-frequency measurements of residual water cut in-line moisture meter, with adjustable parameters of the control system for the electric drives of the valves of the in-line vortex-type separator. 2. Mobile installation for preliminary water discharge, containing a pipe vortex sand separator, a pipe vortex gas separator, an in-pipe vortex-type separator with a control system based on a neural network according to claim 1, a three-phase separator unit, a water settling unit, a reagent dosing unit, connected in series by a pipeline system, Moreover, the mobile installation is made in the form of a single monoblock, with a two-tier arrangement of technological blocks placed in frames with the dimensions of 40- and 20-foot cargo containers.