KR101776377B1

KR101776377B1 - Micro capsule for inhibiting produntion of deposites and preparing method of the same

Info

Publication number: KR101776377B1
Application number: KR1020150046646A
Authority: KR
Inventors: 김신현; 이상석; 서유택; 손영훈
Original assignee: 한국과학기술원
Priority date: 2015-04-02
Filing date: 2015-04-02
Publication date: 2017-09-08
Also published as: KR20160119293A

Abstract

The present invention relates to a microcapsule containing a precipitate formation inhibitor, and more particularly, to a microcapsule in which a precipitate formation inhibitor is selectively discharged under a precipitate production condition and a method for producing the microcapsule.
When the microcapsule of the present invention is used to selectively release the precipitate formation inhibitor selectively only in the transport pipe sediment production condition inside the transport pipe, generation of precipitates in the transport pipe is effectively suppressed by using a small amount of inhibitor when transporting gas or crude oil . In addition, since the microcapsule of the present invention suppresses the formation of precipitates in the gas or crude oil conveying pipe by using a small amount of inhibitor, it is possible to reduce the cost of the additional separation process after the transfer of the crude oil and to reduce the environmental pollution burden by using a small amount of inhibitor .
By using the microcapsule of the present invention, it is possible to increase the inhibition efficiency by preventing cross-contamination among the respective precipitant inhibitors by releasing only one or more kinds of precipitant inhibitors on the respective capsules and releasing them only under the respective precipitate production conditions.

Description

TECHNICAL FIELD [0001] The present invention relates to microcapsules for inhibiting the formation of precipitates and methods for preparing the same,

The present invention relates to a microcapsule containing a precipitate formation inhibitor, and more particularly, to a microcapsule in which a precipitate formation inhibitor is selectively discharged under a precipitate production condition and a method for producing the microcapsule.

In the gas or oil production process, when transporting gas or crude oil from the process station to the processing plant through the platform, the sediments, such as wax, hydrate, and asphaltene, inhibit the flow of gas or crude oil in the gas or crude oil pipeline Causing serious problems.

For example, the gas hydrate is a kind of inclusion compound, which is a stable compound in which a gas molecule existing in a natural gas is physically bonded and formed in a cavity formed by water molecules under high pressure and low temperature conditions Crystal. It is known that more than 100 gas molecules form hydrate because the hydrate formers or the gas molecules of the object molecules are trapped in the solid phase lattice of the water molecules which are hydrogen-bonding molecules under the conditions of low temperature and high pressure. Since the above-mentioned gas hydrate is generally formed in an atmosphere of low temperature and high pressure, generation of the gas hydrate is not a serious problem in the atmosphere where the normal temperature and normal pressure are maintained. However, in the case of the deep sea at low temperature and high pressure, or at the production facility of the offshore oil-gas field where high pressure is maintained, the environment where the gas hydrate is generated naturally is formed, and as a result, gas hydrate is generated at an undesired place . In particular, in the case of the oil and gas industry, a pipe pipe for collecting and transporting oil or gas from the deep sea is placed for a long time under a low-temperature and high-pressure environment in the sea, and a low-molecular- The gases react with water and the like to form a solid state gas hydrate. As described above, the gas hydrate formed on the pipe pipe or the like blocks the pipe pipe to obstruct the transfer of the production fluid.

A great deal of effort has been made to suppress the formation of the precipitate in the oil and gas industry, and many inhibitors have been developed, since the once-occurring precipitate takes a lot of cost and time to remove and the work is stopped during the removal of the precipitate . However, existing sediment inhibitors required a large amount of inhibitor because the sediment inhibitor had to be delivered throughout the production line. This method uses an excess of inhibitor, which necessitates an additional separation step in the future, resulting in high costs and environmental problems. In addition, simultaneous infusion of various inhibitors may result in reduced inhibitor efficiency due to cross-contamination between inhibitors. Accordingly, there is a demand for development of a method capable of effectively suppressing the generation of sediments in the conveyance pipe during the transfer of gas or crude oil.

[Prior Patent]

1. Korean Patent No. 10-0263421

2. Korean Patent No. 10-0541753

The present invention provides a microcapsule capable of effectively preventing formation of a precipitate by releasing a precipitate formation inhibitor only in a precipitate producing condition inside a crude oil transportation pipe.

In one aspect,

A core containing a precipitate formation inhibitor; And

Wherein the shell is broken under the condition of producing a precipitate in a transport tube during transport of the capsule along with the gas or crude oil in the transport tube to release the precipitate formation inhibitor, The present invention relates to a microcapsule for inhibiting the formation of a precipitate.

In another aspect,

Forming a droplet using a first fluid comprising a precipitate formation inhibitor as an internal phase, and a second fluid comprising an externally polymerizable polymer monomer; And

And a step of photocuring or thermosetting the droplet. The present invention also relates to a method for producing microcapsules for inhibiting the formation of precipitates.

When the microcapsule of the present invention is used to selectively release the precipitate formation inhibitor selectively only in the transport pipe sediment production condition inside the transport pipe, generation of precipitates in the transport pipe is effectively suppressed by using a small amount of inhibitor when transporting gas or crude oil . In addition, since the microcapsule of the present invention suppresses the formation of precipitates in the gas or crude oil transfer tube by using a small amount of inhibitor, it is possible to reduce the cost of the additional separation process after the transfer of the crude oil and to reduce the environmental pollution burden by using a small amount of inhibitor .

By using the microcapsules of the present invention, one or more precipitant inhibitors can be separately loaded into different capsules and released only under the conditions of each precipitate, thereby preventing mutual contamination between the respective precipitant inhibitors, thereby increasing the inhibition efficiency.

1 is a conceptual diagram showing destruction of a microcapsule of the present invention and a capsule under a condition of producing a precipitate.
2 is a schematic diagram showing the destruction characteristics of microcapsules according to the content of the phase change material.
3 is an optical microscope image of HDDA microcapsules containing PVP.
Figure 4 is an optical microscope image of ETPTA microcapsules containing PVcap.
5 is an image showing destruction of a microcapsule according to temperature and stirring conditions.
FIG. 6 is an optical microscope image showing destruction of microcapsules under agitation under hydrate production conditions. FIG.
7 and 8 are schematic views showing a microfluidic device capable of producing microcapsules.

The present invention relates to a microcapsule which releases a precipitate formation inhibitor under the condition of producing a precipitate in a gas or a crude oil transfer tube. Embodiments of the present invention will be described in detail.

1 is a conceptual diagram showing destruction of a microcapsule of the present invention and a capsule under a condition of producing a precipitate.

1, the microcapsule of the present invention comprises a core 10; And a shell 20 surrounding the core.

The core 10 contains a precipitate formation inhibitor.

The precipitate is a substance which precipitates in the transfer pipe during the transfer of gas or crude oil and interferes with the transfer of gas or crude oil. For example, the precipitate may be wax, hydrate or the like, but is not limited thereto.

The wax is a complex consisting of normal paraffin, isoparaffin, and cycloparaffin having 18 to 65 carbon atoms. When the temperature of the oil becomes below the wax production temperature, the kinetic energy of the paraffin particles, which is the main component of the wax, decreases, and the particles are formed as crystals due to the reduction of the intergranular distance. The wax is usually produced at 40 DEG C or lower, but crystals are formed to increase the viscosity of the fluid below about 20 DEG C to interfere with the fluidity of the tube.

Hydrates are produced by physically bonding water molecules and hydrocarbon molecules such as methane, ethane, propane, nitrogen, carbon dioxide and hydrogen sulfide molecules, and are produced under low temperature and high pressure conditions, ie, at pressures of 25 bar or less and 26 bar or less.

The precipitate formation inhibitor can be used without any particular limitation as long as it is commonly used in the art. For example, the hydrate inhibitor may be polyvinylcaprolactam (PVcap) or polyvinylpyrrolidone (PVP), and the wax inhibitor may be polycarboxylate or polyacrylate, but is not limited thereto. The hydrate inhibitor may be contained in the core in a state dissolved or dispersed in ethylene glycol or water, and the wax inhibitor may be contained in the core in a state dissolved or dispersed in an organic solvent.

Depending on the kind of the precipitate formation inhibitor, the core 10 may be a hydrophilic or lipophilic droplet. On the other hand, the solvent or water in the droplets forming the core 10 may be removed later, and only the precipitate formation inhibitor may remain in the core.

The shell 20 is a film of a cured polymer, and the polymer forming the shell may be any material that can be photo-cured or thermally cured. For example, the shell may be formed from a polymeric monomer containing a carbon-carbon unsaturated group.

The carbon-carbon unsaturated group-containing polymeric monomer may be selected from the group consisting of aryl acrylate, benzyl acrylate, butoxy ethyl acrylate, butoxy triethylene glycol acrylate, cyclohexyl acrylate, dicyclopentyl acrylate, dicyclopentenyl acrylate , 2-ethylhexyl acrylate, glycerol acrylate, glycidyl acrylate, heptadecafluorodecyl acrylate, 2-hydroxyethyl acrylate, isobornyl acrylate, 2-hydroxyethyl methacrylate, 2- Methoxyethyl acrylate, methoxyethylene glycol acrylate, methoxyethylene glycol acrylate, methoxyethylene glycol acrylate, methoxyethylene glycol acrylate, methoxyethylene glycol acrylate, isopropyl methacrylate, Methoxy dipropylene glycol acrylate, octafluorophene Acrylate, phenoxyethyl acrylate, stearyl acrylate, trifluoroethyl acrylate, acrylated cyclohexyl diacrylate, diethylene glycol diacrylate, (tri) ethylene glycol diacrylate, polyethylene glycol diacrylate Acrylate, dipentaerythritol hexaacrylate, dipentaerythritol monohydroxypentaacrylate, ditrimethylol propane tetraacrylate, glycerol diacrylate, methoxylated cyclohexyl diacrylate, neopentyl glycol di Acrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, propylene glycol diacrylate, polypropylene glycol diacrylate, triglycerol diacrylate, trimethylolpropane triacrylate, HDDA (1, 6-hexanediol diacrylate), EGPEA (Ethylene glycol phenyl ether acrylate), HDDA (1,6-hexanediol diacrylate), silicone methacrylate monomer (SB4722), ETPTA (ethoxylated trimethylolpropane triacrylate), or a compound containing methacrylate instead of acrylate or γ-methacryloxypropyl trimethylene Butoxysilane, and the like, but is not limited thereto.

Preferably, the polymeric monomer forming the shell 20 is selected from the group consisting of Ethoxylated trimethylolpropane triacrylate (ETPTA), HDDA (1,6 Hexanediol diacrylate), SB4722 (Silicone methacrylate monomer), EGPEA (Ethylene glycol phenyl ether acylate) (ethylene glycol) diacrylate, HEMA (2-hydroxyethyl methacrylate) and GDDA (Glycerol 1,3-diglycerolate diacrylate).

The polymer shell 20 is broken in the condition of the precipitate in the transport tube while the capsule is being transported together with the gas or the crude oil in the transport pipe and the precipitate formation inhibitor contained in the core 10 is released.

The capsule may be broken by the shear stress of the gas or crude oil due to the increase in the brittleness of the polymer shell due to a decrease in the temperature in the transport pipe to release the inhibitor.

Specifically, when the precipitate is hydrate, the temperature in the transport pipe is 25 ° C or lower, preferably 18 ° C or lower, and the shear stress applied to the shell is 5 Pa or higher, preferably 6 Pa or higher, more preferably 6.7 Pa or higher The polymer shell may be destroyed.

In addition, when the precipitate is wax, the polymer shell may be broken if the temperature in the transport pipe is 40 ° C or lower, preferably 30 ° C or lower, but the present invention is not limited thereto. For example, in the case of crude oil having an API viscosity of about 22, wax may be produced at about 30 degrees or less.

The shell of the polymer shell 20 may be broken due to increased brittleness of the polymer shell due to the precipitate crystals deposited on the surface of the polymer shell 20 after being deposited on the surface of the polymer shell 20 in the condition of producing the precipitate inside the transport tube. For example, when hydrate crystals are formed on the surface of the polymer shell under the conditions of hydrate formation in an oil or gas transfer tube, fine cracks are generated in the polymer membrane due to the nature of the hydrate particles similar to ice particles, brittleness), which can be destroyed by shear stress applied to the polymer shell.

The larger the radius of the polymer shell or the thinner the thickness, the more the embrittlement increases. Therefore, it is necessary to adjust the radius and the thickness of the polymer shell so that the shell is easily broken under the condition of producing the precipitate. If the radius of the polymer shell is too large or the thickness is too small, the capsule may be broken before the capsule is subjected to the conditions for producing the precipitate. Therefore, the radius and thickness of the polymer shell should be adjusted for stabilization of the capsule. For example, the radius and thickness of the ETPTA polymer shell releasing the hydrate formation inhibitor under hydrate formation conditions may be 0.01 <thickness / radius <0.3, more preferably 0.05 <thickness / radius <0.2.

The capsule may further include a phase change material in the polymer shell 20 and the phase change material may be converted into a solid phase at a temperature lower than the precipitate formation temperature in the transport tube to increase the brittleness of the polymer shell have.

Referring to FIG. 2, referring to FIG. 2, FIG. 2 (a) is a microcapsule in which a phase change material is not contained in a shell. On the other hand, FIG. 2 (b) shows a case where the phase change material is contained in the shell and has a fragile characteristic (brittleness) when the ambient temperature of the microcapsule is below the freezing point of the phase change material. As a result, the present invention can provide a microcapsule that is easily broken by an external impact at a temperature lower than the precipitate production temperature in the gas or petroleum pipeline by using a phase change (liquid to solid) of the phase change material dispersed in the shell. Furthermore, the microcapsule of the present invention can appropriately select a phase change material to break the shell in various kinds of precipitate production temperature ranges, thereby releasing the precipitation inhibitor of the core.

The phase-change material is mixed with a monomer to form a shell. However, during the polymerization of the monomer, the phase-change material is uniformly dispersed in the shell without being affected by polymerization and is retained in its properties. Fine phase separation can occur from the polymer formed.

The phase change material may be any known phase change material without limitation. For example, the phase change material may be oil, paraffinic hydrocarbon or organic solvent.

The phase change material may have a freezing point of 1 to 40 占 폚, and desirably 4 to 30 占 폚.

The paraffinic hydrocarbon may be selected from the group consisting of n-octanoic acid (freezing point 61.4 ° C), n-heptacoic acid (freezing point 59 ° C), n-hexanoic acid (freezing point 56.4 ° C) N-nonadecane (32.1 占 폚), n-nonadecane (32.1 占 폚), n-heptanoic acid (44.9 占 폚) n-hexadecane (18.2 占 폚), n-pentadecane (10 占 폚), n-tetradecane (5.9 占 폚), and n-tridecane (-5.5 DEG C), and is not limited thereto.

The freezing point of the paraffinic hydrocarbon may range from 1 to 40 캜.

The phase change material and the polymer material may be present in a weight ratio of 1: 100, preferably 1: 0.1 to 50.

The microcapsules may contain magnetic nanoparticles in the polymer shell 20. If the shell containing the magnetic nanoparticles is used in the shell layer, the shell is broken under the condition of producing the precipitate in the transport tube, and the polymer shell layer can be easily separated using external magnetic force after releasing the precipitate formation inhibitor . In addition, when the magnetic nanoparticles are contained in the polymer shell 20, the microcapsules in which the inhibitor is not released can be easily recovered and reused later by using external magnetic force.

In another aspect, the present invention relates to a method of making the microcapsule.

The method for manufacturing a microcapsule of the present invention includes forming droplets using a first fluid and a second fluid, and photocuring or thermally curing the droplet.

The first fluid comprises a precipitate formation inhibitor to form an internal phase. The precipitate may be a substance that interferes with transport in the transport pipe during the transfer of the crude oil or gas, i.e. wax, hydrate, asphaltene or resin.

The second fluid comprises a polymeric monomer to form an outer phase. At this time, the second fluid may contain a surfactant if necessary for interfacial stabilization.

The first fluid and the second fluid are each a material that is not well mixed with each other. For example, when the precipitation inhibitor contained in the first fluid is a wax inhibitor dissolved in a fat-soluble solvent, the polymer contained in the second fluid may be a hydrophilic polymer. In addition, when the sediment formation inhibitor contained in the first fluid is a hydrate inhibitor dissolved in a water-soluble solvent, the polymer contained in the second fluid may be a lipophilic polymer.

The droplets of the present invention can be prepared by various known methods. For example, the droplet can form a double droplet through a microfluidic device or a bulk emulsion production method, but is not limited thereto.

More specifically, referring to Fig. 7, there is shown a microfluidic device used as one device for forming droplets. The microfluidic device includes an injection capillary 110, a collection capillary 120, and an outer capillary 130. The surface of the injection capillary 110 may exhibit hydrophobicity or hydrophilicity. The surface of the collection capillary 120 may exhibit a wetting property of the third fluid. The first fluid is injected into the injection capillary 110 and the second fluid flows into the gap B between the outer capillary 130 and the injection capillary 110. In addition, a third fluid, in which the droplet is composed of the first fluid and the second fluid, can be dispersed into the outer capillary tube 130 and the collection capillary tube 120 in a continuous phase, Lt; / RTI > An interface 140 is formed between the injection capillary 110 and the collection capillary 120 to form a first fluid and a third fluid. A first fluid, a second fluid, a third fluid A hole 141 through which the droplet can pass is generated. As the first fluid, the second fluid, and the third fluid meet and flow through the holes 141, the first fluid is surrounded by the second fluid and is once again surrounded by the third fluid so that w / o / w or o / w / o. < / RTI >

The curing step can be used without particular limitation as long as it is a photo-curing or thermosetting method of curing the polymer monomer with a polymer. For example, the curing step may be performed by irradiating ultraviolet light onto the lipophilic or hydrophilic polymer monomer contained in the droplet formed of w / o / w or o / w / o. More specifically, for example, the ultraviolet ray irradiation may be performed for 0.1 to 10 seconds at a light intensity of ¹ to 100 mW / cm ^{2. In} the microfluidic device of FIG. 5, 150) can be used to polymerize the polymer monomer.

As another concrete example, Fig. 8 shows a microfluidic device used as one device for forming droplets. The droplet forming apparatus includes an injection capillary 210, an inner capillary 240, a collection capillary 220, and an outer capillary 230. The surface of the injection capillary 210 may exhibit hydrophobicity or hydrophilicity. The surface of the collection capillary 220 may exhibit a surface property that the third fluid may be wetted. The first fluid is injected into the inner side A of the inner capillary tube 240 and the second fluid is injected into the space B between the injection capillary tube 210 and the inner capillary tube 240. And injects a third fluid capable of dispersing the droplet constituted by the first fluid and the second fluid into the gap C between the injection capillary 210 and the outer capillary tube 230 as a continuous phase. The third fluid is a material from which the first fluid and the second fluid can be dispersed.

The first fluid and the second fluid are separated from each other in the injection capillary 210. That is, the first fluid flows in the central portion of the injection capillary 210, and the second fluid flows into the injection capillary tube 210 And flows around the first fluid. W / o / w or o / w / o emulsion is formed while the first fluid and the second fluid are dropped into the third fluid from an orifice formed at the end of the injection capillary.

The curing step can be used without particular limitation as long as it is a photo-curing or thermosetting method of curing the polymer monomer with a polymer. For example, the curing step may be performed by irradiating ultraviolet light onto the lipophilic or hydrophilic polymer monomer contained in the droplet formed of w / o / w or o / w / o. More specifically, for example, the ultraviolet ray irradiation may be performed for 0.1 to 10 seconds at a light intensity of ¹ to 100 mW / cm ^{2. In} the microfluidic device of FIG. 5, 250) can be used to polymerize the polymer monomer.

The method of manufacturing the microcapsule may control the thickness of the second fluid, that is, the thickness of the polymer shell in the capsule, by controlling the volume ratio of the first fluid and the second fluid. Increasing the ratio of the second fluid to the first fluid may increase the thickness of the polymer shell of the capsule. The radius of the capsule can be adjusted by adjusting the flow rate of the third fluid relative to the first fluid and the second fluid. Also, the radius of the capsule can be adjusted by adjusting the size of the injection part and the collection part of the device.

The microcapsules formed by curing the liquid droplets may contain a phase change material in the second fluid at the time of manufacturing, and the phase of the phase change material may be changed in accordance with the change of the surrounding temperature of the capsule, Can be changed. More specifically, the phase change material may be converted into a solid phase at a temperature lower than the precipitate formation temperature in the transport tube, thereby increasing the embrittlement of the polymer shell formed upon curing of the droplet.

The content of the microcapsule described above with respect to the method for producing the microcapsule of the present invention can be all applied.

Hereinafter, the present invention will be described in more detail with reference to the following examples. However, the following examples are for illustrative purposes only and are not intended to limit the scope of the present invention.

Example 1: Preparation of microcapsules carrying precipitate formation inhibitor

(1) Preparation of HDDA microcapsules containing PVP

Microcapsules were prepared using the apparatus of FIG.

An aqueous phase containing 30wt% of PVP was injected into the injection capillary, the HDDA monomer was injected into the B space, and a continuous phase was formed by injecting 10% PVA in the C space. The droplets falling from the back of the collecting capillary to the collecting solvent were irradiated with UV for 10 seconds to cure the continuously generated droplets. FIG. 3 shows an optical microscope image of the HDDA microcapsules containing PVP.

(2) Preparation of ETPTA microcapsules containing PVcap

Microcapsules were prepared using the apparatus of FIG.

A 1: 1 mixture of ethylene glycol and water containing 50 wt% of PVcap was injected into the injection capillary, ETPTA monomer was injected into the B space, and a continuous phase was formed by injecting 10% PVA-containing water into the C space Respectively. The droplets falling from the back of the collecting capillary to the collecting solvent were irradiated with UV for 10 seconds to cure the continuously generated droplets. FIG. 4 shows an optical microscope image of ETPTA microcapsules containing PVcap.

Example 2 Preparation of Microcapsules in Response to Hydrate Production Conditions and Shear Stress

Microcapsules were prepared using the apparatus of Fig.

Water and red dye were mixed and injected into the injection capillary. ETPTA monomer was injected into the B space and a continuous phase was formed by injecting 10% PVA into the C space. The droplets falling from the back of the collecting capillary to the collecting solvent were irradiated with UV for 10 seconds to cure the continuously generated droplets.

Experimental Example 1: Destruction of microcapsules according to hydrate production condition and shear stress

The microcapsules prepared in Example 2 were dispersed in water and charged into the reactor.

The temperature of the reactor was controlled at 20 ° C., 15 ° C. or 10 ° C. under low temperature conditions in which hydrate was generated and the pressure was changed from 100 rpm (0.46 Pa) to 600 rpm (6.7 Pa) Were observed.

According to FIG. 5, it was observed that the pigment of the microcapsules was ejected at a temperature of 15 DEG C or lower and 600 rpm. The microcapsules did not eject dye at a shear pressure lower than 600 rpm, even though the microcapsule was below 15 ° C, and no dye was ejected at 20 ° C even at 600 rpm. Therefore, it can be confirmed that the polymer film of the microcapsule is broken and the substance contained in the core is released when the hydrate is well-produced at 15 ° C or less and when the shear stress condition is 600 rpm or more.

According to FIG. 6, in the case of stirring at 600 rpm under a low temperature condition in which hydrate is generated, the film of the capsule is broken and all of the pigments carried therein are released.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments.

Claims

A core containing a precipitate formation inhibitor; And
A capsule comprising a polymer shell surrounding the core,
The brittleness of the polymer shell is increased under the condition of producing the precipitate in the transport pipe during the transportation of the capsule along with the gas or the crude oil in the transport pipe, the shell is broken to release the precipitate formation inhibitor,
Wherein the capsule further comprises a phase change material in the polymer shell and the phase change material is converted into a solid phase at a temperature below the precipitate formation temperature in the transport tube to increase the embrittlement of the polymer shell, Microcapsules for inhibition.

The microcapsule for inhibiting the formation of precipitates according to claim 1, wherein the capsule is destroyed by shear stress of gas or crude oil due to increase in brittleness of the polymer shell due to a decrease in temperature in the transport pipe, thereby releasing the inhibitor.

delete

The microcapsule for inhibiting the formation of precipitates according to claim 1, wherein the precipitate is wax, hydrate, asphaltene or resin.

The microcapsule for inhibiting the formation of precipitates according to claim 1, wherein when the precipitate is hydrate, the polymer shell is destroyed when the temperature in the transport pipe is 25 ° C or less and the shear stress applied to the shell is 5 Pa or more.

The polymer shell according to claim 1, wherein the polymer shell is selected from the group consisting of Ethoxylated trimethylolpropane triacylate (ETPTA), HDDA (1,6 Hexanediol diacrylate), SB4722 (Silicone methacrylate monomer), EGPEA (Ethylene glycol phenyl ether acylate), PEGDA ), HEMA (2-Hydroxyethyl methacrylate) or GDDA (Glycerol 1,3-diglycerolate diacrylate).

The microcapsule for inhibiting the formation of precipitates according to claim 1, wherein the shell has a radius and a thickness of 0.01 <thickness / radius <0.3.

The microcapsule for inhibiting the formation of precipitates according to claim 1, wherein when the precipitate is wax, the polymer shell is broken when the temperature in the transport pipe is 30 캜 or less.

delete

The method according to claim 1, wherein the capsule further comprises magnetic particles in the polymer shell, and the microcapsules in which the magnetic particles are not released or released can be easily recovered by external magnetic force and reused. Microcapsules.

The microcapsule for inhibiting the formation of precipitates according to claim 1, wherein the freezing point of the phase change material is 1 to 40 ° C.

The microcapsule for inhibiting the formation of precipitates according to claim 1, wherein the phase change material is a paraffinic hydrocarbon.

A method for producing a capsule which is broken in the condition of producing a precipitate in a transport tube during delivery with gas or crude oil inside the transport tube to release a precipitate formation inhibitor contained in the capsule,
Forming a droplet by using a first fluid containing a precipitate formation inhibitor due to an internal phase, a polymer externally polymerizable monomer or a second fluid including a mixture of a polymer monomer and a phase-change material, and curing the droplet , &Lt; / RTI &
Controlling the thickness of the polymer shell by controlling the volume ratio of the first fluid and the second fluid,
The polymer shell is broken due to increased brittleness,
Wherein the phase change material is converted into a solid phase at a temperature lower than the precipitate formation temperature in the transport tube to increase the brittleness of the polymer shell.

14. The method of claim 13, wherein the method further comprises controlling the radius and thickness of the shell to 0.01 <thickness / radius <0.3.

A method for producing a capsule which is broken in the condition of producing a precipitate in a transport tube during delivery with gas or crude oil inside the transport tube to release a precipitate formation inhibitor contained in the capsule,
Forming a droplet by using a first fluid containing a precipitate formation inhibitor due to an internal phase, a polymer externally polymerizable monomer or a second fluid including a mixture of a polymer monomer and a phase-change material, and curing the droplet , &Lt; / RTI &
The polymer shell, in which the polymer monomer is cured, increases in embrittlement in the condition of producing a precipitate in the transport tube,
Wherein the phase change material is converted into a solid phase at a temperature lower than the precipitate formation temperature in the transport tube to increase the brittleness of the polymer shell.

16. The method of claim 15, wherein the phase-change material and the polymeric monomer are added in a weight ratio of 1: 0.1 to 50.

16. The method according to claim 13 or 15, wherein the precipitate is wax, hydrate, asphaltene or resin.