CN118065818A - Flow control valve with magnetic insert to prevent scale formation - Google Patents

Abstract

The main object of the present disclosure is to prevent scale formation in particular in the bore of ICV and SSV flow control valves by providing a magnetic insert arrangement, which is adapted to be inserted into the respective bore so as to provide a sufficient magnetic field in the circumference of the valve. The magnetic insert is manufactured in a ring-shaped form and in a design that when constrained within the adapter ring provides sufficient compression to secure the magnetic ring to the wall of the adapter ring and thereby secure the adapter ring to the wall of the ICV or SSV bore. In this way, the application of the magnetic field promotes a change in the equilibrium curve of the crystal formation, thus promoting the preferential formation of hexagonal calcite over calcite. The crystal size formed in calcite in the absence of a magnetic field is significantly reduced to that formed in hexagonal calcite in the presence of a magnetic field, so that the hexagonal calcite crystals are more easily carried and guided by the production stream and thus do not allow the crystals to adhere to the area surrounding the valve bore.

Description

Flow control valve with magnetic insert to prevent scale formation

Technical Field

The present disclosure is in the field of controlling petroleum production operations, in particular controlling the flow of different production zones to a production string of an oil well, more particularly reducing the formation of scale in a hole by adapting a flow control valve, which may be an ICV (inlet control valve) or an SSV (sliding sleeve valve)

Background

In the petroleum industry, brine scale is one of the greatest challenges in ensuring subsea well flow. The low reliability of chemical injection systems, the difficulty in using proper dosages of inhibitors due to dynamic production, and the inability to use chemical injection in lower completions of certain well formations have prompted the development of alternatives to scale inhibition.

Scale occurs primarily in porous media (reservoirs), reservoir/production well interfaces, production tubing strings, and surface facilities. Where the aqueous phase reaction is far from equilibrium, the rate of reaction between the injected water and the incompatible chemicals in the formation water is the primary parameter determining the scale strength. In porous media, this rate is greatly affected by flow rate, diffusion/dispersion and pore geometry.

The main parameters affecting scale formation are: time, pH, pressure, temperature, particle size, agitation, flow rate, composition, and surface energy.

The formation of scale salts such as barium sulfate may occur by uniform nucleation or non-uniform nucleation.

Near the production well where the flow is more turbulent, thermodynamic effects increase the potential for scaling, especially in the case of non-uniform reservoirs where the flow comes from different layers. Thus, the areas near the production well are most prone to mixing of incompatible waters (SORBIE and MACKAY, literature 2000), and in addition, these areas are the convergence points for all circulating waters within the reservoir.

However, in the case of surface equipment, when there is direct mixing of the incompatible water, it eventually occurs in the production process. This phenomenon is common when producing wells containing water streams of mainly components from the formation (e.g., high concentrations of barium) and wells containing high levels of sea water with high levels of sulfate at the same time, the mixture forms barium sulfate.

In these fields, seawater is typically used to displace oil and maintain reservoir pressure. Thus, in these fields, scale is very common due to the incompatibility of the seawater and formation water mixtures. Thus, when the injection of seawater into the reservoir begins, the seawater mixes with the formation water (formation water). Since the chemical composition of water is often very different, scaling may begin due to supersaturation of poorly soluble salts.

Scale in the equipment can lead to reduced process efficiency, directly resulting in increased pressure and heat loss in the system, thereby increasing the energy consumption and chemical consumption for heating the fluid to be treated.

An alternative method to minimize this effect is to isolate the well when there is more than one production run and inject a scale inhibitor into the surface line.

For example, collins (2004) proposed three different barium sulfate precipitation behavior when SR (saturation ratio) is greater than 1, SR is equal to 1, and SR is less than 1. The tendency to scale may be related to the SR of the produced water. And the saturation ratio can be calculated by adding the activities of barium ions and sulfate ions to the solubility product of barium sulfate.

For higher values of SR (SR > 1) immediate precipitation occurs at the mixing point, resulting in a reduced saturation ratio and the formation of large crystals that form in solution and deposit on the walls of the tubular string in the base of the well.

For intermediate values of SR (sr=1), nucleation and precipitation occurs on the column wall by virtue of fast kinetics, resulting in smaller crystals and scale formation at the base of the column.

For lower values of SR (SR < 1), nucleation may be temporarily slowed down, thereby moving the fluid within the string. As the pressure and temperature on the path decrease, the SR will increase, with a consequent increase in nucleation and crystal growth rates. However, as the temperature decreases, the precipitation rate also decreases, bringing the scale closer to the surface.

The pilot production program and permanent downhole manometer (PDG) data are important to evaluate the changes in IP and fouling rates. The test production may also be used to evaluate the performance of scale removal/scale inhibition interventions.

The design of the string and its assembly depends on the type of well, which in turn depends on the situation of the well to be completed. Thus, a pipe string may have multiple components in its composition, and the diameter variation of a majority of these components is related to the diameter of the pipe string. In this way, fouling may begin in the equipment, resulting in a production string being obstructed.

One of the most susceptible to scale formation is the bore of an Intelligent Completion Valve (ICV) in the production string. Scale growth enters the production string through the bore of an Intelligent Completion Valve (ICV), which can even cause clogging of the bore if not cleared in time.

Thus, in view of the above-described problems with scale formation inside equipment in an oil well production string, the present disclosure prevents scale formation on the edges of the hole by disposing a magnetic insert in the flow passage hole of the valve.

Some prior art documents disclose the same techniques as the objects of the present disclosure, but there are still some unresolved drawbacks therein.

PI 0901552-3 discloses a magnetohydrodynamic device (D) interposed between two sections of a production string (C). The device (D) comprises a plurality of magnets (5, 6) having a suitable and constant magnetic field and regularly spaced such that a fluid flow (F) originating from the well (P) flows into the production string (C) through the space between the plurality of magnets, the magnets (5, 6) being arranged in a substantially cylindrical shape, wherein the polarity arrangement between them is such that a total annular magnetic flux is generated with respect to the cylindrical configuration of the device (D) and the total annular magnetic flux acts transversely to the fluid flow (F) through between two adjacent magnets (5, 6).

PI 0901552-3 also discusses the precipitation of calcium carbonate, which can be crystallized into three polymorphic varieties (polymorphic variety): calcite, hexagonal calcite (vaterite) and aragonite. Although similar to the present disclosure, it also uses the physical principle of magnetic energy to prevent the formation of salt-containing scale, it should be noted that the primary difference is precisely the arrangement of the magnetic rings so that they act specifically on the valve bore.

In other words, the present disclosure comprises an adapter ring for coupling a magnetic ring, which is specifically arranged in a valve bore and along the circumference of the valve bore, which allows to solve a more specific technical problem, resulting in a functional improvement of the use of the valve.

Document BR 1020220143285 describes a device for installation in a magnetic SUB with a magnetic device of diameter, which aims at repairing and reducing inorganic and organic scale in a production string. The device comprises a permanent magnet (1) and a magnet separator plate (2), preferably made of superalloy grade steel and/or a special nickel alloy. The magnets are distributed in a ring shape to form a cylindrical magnetic arrangement in a shape different from the conventional arrangement of Halbach.

Although similar to the present disclosure, since it also uses the physical principle of magnetic energy to prevent the formation of salt-containing scale, it should be noted that the main difference is precisely the arrangement of the magnetic ring so that it acts specifically on the valve bore. In other words, the shape of the magnets and their arrangement in the valve are such that a specific functional improvement is achieved at the site where scale formation is most severe.

EP 1029824 discloses a system consisting of special measures and equipment by means of which salt aggregation dissolved in water and/or other liquids, fluids and/or hydrocarbons, gases can be prevented even if the water and/or liquids, fluids and/or hydrocarbons, gases are subjected to heating or cooling.

The system of EP 1029824 basically comprises equipment mounted directly downstream of the water intake or meter provided by the water supply managing the pipeline or well or other equipment.

The system is characterized in that it uses a device (1) comprising a natural magnet, electromagnet or the like (4), the system of which is formed by a central unit (7) and a satellite unit (8), which must be located respectively directly below the input end C of the main water supply and close to a peripheral unit (9) representing a single use, and these devices are oversized with respect to the actual capacity of the duct.

Although similar to the present disclosure, since it also uses the physical principle of magnetic energy to prevent the formation of salt-containing scale, it should be noted that the main difference is precisely the arrangement of the magnetic ring so that it acts specifically on the valve bore.

The purpose of RU 93012668 is to increase the efficiency of magnetic liquid activation, thereby avoiding unnecessary loss of the magnetic ring magnet and exacerbation of hydrodynamic mixing of the liquid.

The apparatus of RU 93012668 is intended for magnetohydrodynamic activation of well fluids to avoid scaling of hard salts and resin-paraffin deposits on the inner surface of the pipe. The invention aims to improve the magnetic activation efficiency of a liquid by avoiding non-productive magnetic energy loss of the ring magnet and exacerbation of hydrodynamic mixing of the liquid.

The magnets used in RU 93012668 were found to be annular and mounted with non-magnetic spacers for the same purpose as the present disclosure, i.e., magnetically avoiding salt scaling. There is no mention of valves and valve bores in RU 93012668, which again shows that the solution of the present disclosure is to adjust specific areas of valves located in the production string to achieve specific functional improvements.

CN 20626293 promotes descaling under the action of a magnetic field, and in addition, the descaling also adopts ultrasonic waves, when the ultrasonic waves propagate along the pipeline shell, the crusted salt particles can be separated and/or disintegrated from the surface through shearing action so as to prevent the formation of salt shells, therefore, the two descaling modes are associated, and the effect of removing scaling salt is obvious.

It can be seen that although the application of magnets in CN 20626293 does not necessarily take place on the valve, its effect clearly has a direct impact on the normal operation of the on-off valve and on the overall operation, again showing the technical effect of removing salt-containing scale by means of magnetic energy. It should be pointed out again that the solution of the present disclosure is to adjust the specific area of the valve located in the production string, thus achieving a specific functional improvement.

In short, in analyzing the literature closest to the sought prior art literature, it can be appreciated that the novel shape or arrangement of the valve of the present disclosure described above is primarily based on the arrangement of valve bores arranged along the circumference of the valve, and primarily in that it includes an arrangement of adapter rings for coupling magnetic rings, as none of the literature specifically provides such an arrangement for the proper shape of the bores of ICV and SSV valves.

Since the adapter ring is made of a material having a ductility higher than that of the mounted magnet, the adapter ring promotes improved functionality of the magnetic ring mounting, reducing the likelihood of mechanical failure.

Disclosure of Invention

The main object of the present disclosure is to avoid scale formation in the holes of flow control valves (ICV and SSV) by providing an arrangement of magnetic inserts that are particularly suitable for insertion into the respective holes to provide a magnetic field suitable for the circumference of the valve. The magnetic insert is manufactured in a ring-shaped form and in a design that when constrained within the adapter ring provides sufficient compression to secure the magnetic ring to the wall of the adapter ring and thereby secure the adapter ring to the wall of the ICV or SSV bore. In this way, the application of the magnetic field promotes a change in the equilibrium curve, thus promoting the preferential formation of hexagonal calcite over calcite. The size of the crystals formed in calcite in the absence of a magnetic field is significantly reduced to the size of the crystals formed in hexagonal calcite in the presence of a magnetic field and, therefore, hexagonal calcite crystals are more easily carried and guided by the production stream and thus do not allow the crystals to adhere to the area surrounding the valve bore.

Drawings

To assist in identifying the primary features of the present disclosure, reference is made to the accompanying drawings as follows.

Fig. 1 shows stages of scale formation when ICV valves are manufactured without the present disclosure, indicating that scale growth through the pores may even promote clogging of the pores.

In fig. 2, a magnetic insert (3) is shown in detail, comprising a metal adapter ring (2) and a magnetic ring (1) for an ICV valve.

Fig. 3 shows in detail a part of an ICV valve comprising a magnetic insert (3) comprising at least one metal adapter ring (2) and a magnetic ring (1) mounted to the metal adapter ring.

Fig. 4 shows in detail the magnetic insert (3) comprising the metal adapter ring (2) and the magnetic ring (1) for an SSV valve, with details of the outer sheath (4) and the inner sheath (5) of the SSV.

In fig. 5, a part of an SSV valve is shown in detail, comprising a magnetic insert (3) comprising at least one metal adapter ring (2) and a magnetic ring (1) mounted to the metal adapter ring.

Detailed Description

The present disclosure relates to a valve for controlling fluid flow for oil well production, the valve comprising:

at least one magnetic insert ring (1) of a rare earth magnet, circular or oval, said valve presenting at least one lateral hole along its circumference, characterized in that:

The at least one magnetic ring (1) being mounted in one or more holes, each hole further comprising at least one metallic adapter ring (2) surrounding the magnetic ring,

Wherein the adapter ring (2) is particularly adapted to tightly couple together mounted magnets,

Wherein the valve comprises 12 to 16 magnetic rings along its circumference;

The magnetic field of the rare earth magnet (1) is directed towards the center of the metal ring and perpendicular to the fluid flow in the bore channel, wherein preferably the north pole is located on the contact surface of the fluid flow over the first 180 degrees and the south pole is on the other 180 degrees.

Circular magnetic inserts are preferred for Intelligent Completion Valves (ICVs) and oval magnetic inserts are used for Sliding Sleeve Valves (SSVs).

The adapter ring (2), which is particularly suitable for tightly coupling mounted magnets, is preferably made of a suitable metallurgical alloy to encase the magnetic insert such that it is not weakened during mounting.

The magnetic insert is manufactured from a permanent neodymium iron boron magnet and the adapter ring may be manufactured from a metal alloy (e.g., copper or bronze) so long as it has a greater ductility than the magnet and sufficient hardness to allow the adapter ring to receive the magnetic ring and at the same time facilitate adaptation to the valve cartridge in which the magnetic bore is located.

The magnetic insert is manufactured in a ring-like form and in a design that when constrained within the adapter ring provides sufficient compression to secure the magnetic ring to the wall of the adapter ring and thereby secure the adapter ring to the wall of the ICV or SSV bore.

The magnetic ring preferably has anti-friction quality, good workability and good formability, including having controlled wear elements.

Other information about the chemistry, thermal and electrical conductivity, density, hardness, elongation, yield limit, etc. of the metal alloy will depend on the project in which the technology is to be installed and will be related to characteristics such as pH, temperature, pressure, petroleum composition to be produced, BSW (percentage of water produced), CO2 and/or the presence of H ₂ S.

Magnetic inserts that fit the orifices of flow valves have proven to be a highly commercially attractive and technically viable technique because they represent a passive solution to alleviate the problem of clogging of the orifices of these valves due to scaling.

With respect to the drilled designs of each type of flow valve, it should be noted that the dimensions can vary from one to the other, but both valves (ICV and SSV) have cylindrical inner metal jackets, ICV has holes on both the outer and inner walls of the circumferential tube, while SSV has holes only on the outer tube and the inner jacket has no holes, so the installation of the magnetic insert is dependent on the cylindrical tube in which it is installed during the manufacturing of each valve.

Experiments have shown that in the case of open hole completions, the produced oil flow tapers as it passes through the well annulus, the area between the production string and the open hole wall, and into the flow valve bore. This tapering of the oil flow accelerates the formation and growth of scale crystals, thereby increasing the formation of crystals around the valve bore.

In other words, when oil permeates the ICV hole, concentration of flow occurs by tapering, at which time scale crystal formation is accelerated, and then scale is formed. This tapering promotes scale formation on the edges of the valve bore which grows gradually and thus causes the bores to be blocked and to grow towards the interior of the tubular string.

It was found that the application of the magnetic field promotes a change in the equilibrium curve and thus the formation of hexagonal calcite in preference to calcite. The size of the crystals formed in calcite in the absence of a magnetic field is significantly reduced to that of the crystals formed in hexagonal calcite in the presence of a magnetic field and, therefore, hexagonal calcite crystals are more easily carried and guided by the production stream and thus do not allow the crystals to adhere to the area surrounding the valve bore.

Those skilled in the art will appreciate the knowledge presented herein and will be able to reproduce the disclosure in the illustrated embodiments and other variations encompassed within the scope of the appended claims.

Claims (1)

1. A flow control valve with magnetic inserts to prevent scale formation, characterized in that it is used in a production well, it comprises at least one magnetic insert ring (1) of rare earth magnets, circular or oval, it has at least one side hole along its circumference, and:

The at least one magnetic insert ring (1) being mounted in one or more holes, each hole further comprising at least one metallic adapter ring (2) surrounding the magnetic insert ring,

Wherein the adapter ring is particularly adapted to closely couple together the mounted magnets,

Wherein the flow control valve comprises 12 to 16 magnetically insert rings along its circumference;

The magnetic field of the rare earth magnet (1) is directed towards the center of the metallic adapter ring and perpendicular to the fluid flow in the bore channel, wherein preferably the north pole is located at the first 180 degrees on the contact surface of the fluid flow and the south pole is located at the other 180 degrees on the contact surface of the fluid flow.