KR20190041204A - Reclamation apparatus used for salts removal - Google Patents

Abstract

A post-treatment apparatus for salt removal is disclosed. The post-treatment apparatus for salt removal according to an embodiment of the present invention comprises: a salt removing unit for removing salts by evaporating MEG from a MEG mixed fluid in a vacuum-depressurized state; a cooler for cooling the evaporated MEG; a vacuum receiver provided at a rear end of the cooler; and an ejector for ejecting the fluid introduced from an inlet side to an outlet at a high speed to recover gas in the vacuum receiver so as to make the vacuum receiver and the salt removing unit forming a front end thereof into a vacuum state. The post-treatment apparatus for salt removal according to the embodiment of the present invention can effectively remove the salts from the MEG mixed fluid by turning a post-treatment process into a vacuum state by the ejector.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a post-

The present invention relates to a post-treatment apparatus for desalting.

In the production of natural gas in the deep sea, water contained in natural gas exists as a hydrate due to the conditions of low temperature and high pressure. When natural gas is supplied through the pipeline, the hydrate may strike the inside of the pipeline to damage or corrode it, and in severe cases, a pipeline or a gas field may be clogged. Therefore, MEG (Mono Ethylene Glycol) is injected to inhibit the formation of hydrate.

MEG has a strong hydrophilic property to absorb moisture, and more than 90% of the input amount can be recovered from the upper part of the ocean production tower, which is economically advantageous. Since the MEG solution recovered from the upper part of the production tower contains impurities such as water, solubilizing salt and low solubility salt, the MEG regeneration process removes water and salts to extract MEG of high concentration.

The MEG regeneration process consists of a full treatment method (vapor treatment) in which the MEG solution is vaporized at one time to remove the salt, and a pretreatment process is performed to remove the salt first, then to evaporate the solution, There are some processing methods to remove (SLIP STREAM CONCEPT).

FIG. 1 shows the processing procedure of the entire conventional processing method and some processing methods.

Referring to FIG. 1 (a), the entire treatment system removes hydrocarbons in the MEG mixed fluid by the pretreatment apparatus 10.

Next, the post-treatment apparatus 20 removes the salt and the low-solubility salt even if it is solubilized by using the flash.

Next, the water treatment apparatus 30 removes water by using a breaking point difference.

Referring to FIG. 1 (b), some of the treatment methods remove low solubility salts and hydrocarbons in the MEG mixed fluid by the pretreatment device 40.

Next, the water treatment apparatus 50 evaporates water in the MEG mixed fluid, and a part of the flow of the MEG mixed fluid is supplied to the post-treatment apparatus 60.

The post-treatment apparatus 60 removes the salt even when it is used in the MEG mixed fluid through the water treatment apparatus 50. The saline-free MEG may include a small amount of water, and it is joined to the MEG mixed fluid stream from which the water has previously been removed by the water treatment device 50.

The above-mentioned whole treatment method does not cause any problem due to salt because all the salts are removed by using the flash, but a large amount of energy is consumed because the entire MEG mixed fluid must be vaporized to remove the salt .

In addition, some treatment methods are classified as salt and low-solubility salts even if the salt to be removed is solubilized. Low solubility salts are salts that are not soluble in water and include Ca2 +, Mg2 +, and Ba2 +. This should be eliminated, since it is low in solubility and easily deposited to scale the device and degrade process efficiency. On the other hand, the solute salt is Na2 +, K2 +, etc., and these salts do not need to be removed because of their high solubility.

For salt removal by solubilization, the entire treatment regime and some treatment regimes are depressurized using a vacuum pump to evaporate the MEG mixed fluid at low temperatures. At this time, for example, a liquid ring vacuum pump may be used.

However, there is a problem in that the reaching pressure during operation is limited by using a conventional vacuum pump, and a large amount of water is required.

In addition, since the performance varies with the temperature of the water and the water in the vacuum pump must be rotated, a large driving power is required.

Please refer to Korean Patent Laid-Open No. 10-2016-0001283 (published on June 01, 2016) as a technology related to the above-mentioned contents.

Korean Patent Laid-Open No. 10-2016-0001283 (published on June 1, 2016)

An embodiment of the present invention is to provide a post-treatment apparatus for removing a salt effectively from a MEG mixed fluid by turning a post-treatment process into a vacuum state by an ejector.

According to an aspect of the present invention, there is provided a method for removing MEG from a MEG mixed fluid in a vacuum depressurized state to remove salts; A cooler for cooling the evaporated MEG; A vacuum receiver disposed downstream of the cooler; There is provided an apparatus for desalting treatment for desalting, comprising: an ejector for rapidly injecting a fluid introduced from an inlet side into an outlet so as to recover gas in the vacuum receiver to turn the vacuum receiver and the defatting unit constituting the front end thereof into a vacuum state; .

A heat exchanger for performing heat exchange between the MEG mixed fluid in which MEG, salt, and water are mixed and the heated fluid to evaporate moisture in the MEG mixed fluid; A first supply line connecting the heater and the heat exchange unit to the heat exchanger through the heater, and a second supply line connecting the heat exchanger, the heater and the rejection unit, and the moisture is evaporated by the heat exchange, And a second supply line for providing the MEG mixed fluid to the rejection.

A reflux drum provided downstream of the liquefier and a heat exchanger, a liquefier, a reflux drum and an ejector, and a part of the liquefied moisture is discharged from the reflux drum And a fluid supply line that flows into the ejector inlet side to provide a fluid for forming the vacuum state.

The post-treatment apparatus for desalting according to the embodiment of the present invention can effectively remove the salt from the MEG mixed fluid by turning the post-treatment process into a vacuum state by the ejector.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description of the claims.

FIG. 1 shows the processing procedure of the entire conventional processing method and some processing methods.
2 shows a post-treatment apparatus for desalting according to an embodiment of the present invention.
3 shows a post-treatment apparatus for desalting according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments described below are provided by way of example so that those skilled in the art will be able to fully understand the spirit of the present invention. The present invention is not limited to the embodiments described below, but may be embodied in other forms. In order to clearly explain the present invention, parts not related to the description are omitted from the drawings, and the width, length, thickness, etc. of the components may be exaggerated for convenience. Like reference numerals designate like elements throughout the specification.

Referring to FIG. 2, the post-treatment apparatus 100 for removing salts according to an embodiment of the present invention includes a dechlorination unit 110 for removing salts by evaporating MEG from a MEG mixed fluid under vacuum, A cooler 120 for cooling the vaporized MEG that has passed through the decanter 110, a vacuum receiver 130 provided at the rear end of the cooler 120, and a vacuum receiver 130 for rapidly ejecting the fluid, And an ejector 140 for evacuating the vacuum receiver 130 and the defatting unit 110 constituting the front end of the vacuum receiver 130 to a vacuum state.

When the post-treatment apparatus 100 for salt removal according to an embodiment of the present invention is applied to a full treatment method, an MEG mixed fluid in which MEG, water, an ammonium salt, a low solubility salt and a hydrocarbon are mixed Can be introduced into the desorbent 110 in a state in which hydrocarbons are removed by the pretreatment apparatus 10 (see Fig. 1 (a)). At this time, the MEG mixed fluid contains a large amount of water, MEG, solute salt, and low solubility salt.

In this case, the deionized water 110 is depressurized by the ejector 140, which will be described later, to evaporate the MEG from the MEG mixed fluid and remove the salt and the low-solubility salt by solubilization. For example, the salt can be determined to be in a solid state and removed when it is solubilized. At this time, although not shown, the decontamination unit 110 may include a separator for removing the salt.

When the post-treatment apparatus 100 for desalting according to an embodiment of the present invention is applied to some treatment method (SLIP STREAM CONCEPT), a MEG mixed with MEG, water, an ammonium sulfate salt, a low solubility salt and a hydrocarbon The fluid is supplied to the heat exchanging unit 160 in a state where the salt is low in solubility by the pretreatment apparatus 40 (see FIG. 1B) and the water treatment apparatus 50 (see FIG. 1B) Can be introduced. At this time, the MEG mixed fluid contains a small amount of water, MEG, and solute salt.

In this case, the deionized water 110 becomes a vacuum-depressurized state by an ejector 140 to be described later, so that the MEG can be evaporated from the MEG mixed fluid, and the salt can be removed even if it is solubilized.

The cooler 120 cools the vaporized MEG via the dechlorination 110 and turns it into a liquid state. The vaporized MEG may contain water.

The vacuum receiver 130 is brought into a vacuum state by an ejector 140 to be described later, thereby securing process stability and a buffer. The liquid MEG introduced from the cooler 120 is discharged to the next process via the vacuum receiver 130 and the discharge pump 125. At this time, the liquid MEG is partially evaporated through the vacuum receiver 130 to be in a gaseous state, and the gaseous MEG is recovered by the ejector 140 and mixed with the fluid ejected through the outlet of the ejector 140 .

When the post-treatment apparatus 100 for desalting according to an embodiment of the present invention is applied to the entire treatment method, the liquid MEG discharged through the discharge pump 125 described above is supplied to the water treatment apparatus 30 , See Fig. 1 (a)).

In addition, when the post-treatment apparatus 100 for desalting according to an embodiment of the present invention is applied to some treatment methods, the liquid MEG discharged through the discharge pump 125 described above is supplied to the water treatment apparatus 50 1 (b)). ≪ / RTI >

The ejector 140 recovers the gas in the vacuum receiver 130 by ejecting the medium or high pressure fluid introduced from the inlet side at a high speed so as to vacuum the vacuum receiver 130 and the defatted refuse 110 constituting the front end of the vacuum receiver 130. At this time, the recovered gas may include an MEG that has been partially evaporated while passing through the vacuum receiver 130 as described above.

The medium or high-pressure fluid that has passed through the ejector 140 is changed to a low-temperature, high-temperature fluid. The fluid used for the ejector 140 may include steam, water, oil, and the like. The ejector 140 can be, for example, a single stage, and can meet the process operating conditions at a suction pressure of 100 to 760 torr and a final pressure of 50 torr.

As described above, by constituting the vacuum receiver 130 and the ejector 140 that makes the salt rejection 110 constituting the front end of the vacuum receiver 130 into a vacuum state in the post-treatment apparatus 100 for desalination, So that the operation and maintenance can be performed easily. In addition, there is no capacity limitation for designing and manufacturing, the material selection for installation and corrosive fluid is easy, and the replacement period after installation may be long.

Referring to FIG. 3, a post-treatment apparatus 100 for desalting according to another embodiment of the present invention includes a heater 150 for heating a fluid that has passed through an ejector 140, a heat exchanger The heat exchanging unit 160 for evaporating water in the MEG mixed fluid and the ejector 140 and the heater 150 and the heat exchanging unit 160 are connected to the heater 150 The heat exchanging unit 160, the heater 150 and the desiccant 110 are connected to the first supply line L1 through the first supply line L1 and the second supply line L1 to the heat exchanging unit 160, A reflux drum 180 provided downstream of the liquefier 170, a heat exchanger 160, and a second heat exchanger 160. The heat exchanger 160 is connected to the heat exchanger 160, A part of the water liquefied by the liquefier 170 flows toward the inlet of the ejector 140 via the reflux drum 180. The liquid refiner 170 is connected to the reflux drum 180 and the ejector 140, By it may include a fluid supply line (L4) for providing a fluid for vacuum forming.

When the salt removal post-treatment apparatus 100 according to another embodiment of the present invention is applied to the entire treatment method, the MEG mixed fluid in which the MEG, water, solvant bile salt, low solubility salt and hydrocarbon are mixed is supplied to the pretreatment apparatuses 10, (See FIG. 1 (a)), the hydrocarbon may be introduced into the heat exchanging unit 160 in a state where the hydrocarbon is removed. At this time, the MEG mixed fluid contains a large amount of water, MEG, solute salt, and low solubility salt.

In addition, when the post-treatment apparatus 100 for desalting according to another embodiment of the present invention is applied to some treatment method (SLIP STREAM CONCEPT), a MEG mixed with water, an ammonium salt, a low solubility salt and a hydrocarbon The fluid is supplied to the heat exchanging unit 160 in a state where the salt is low in solubility by the pretreatment apparatus 40 (see FIG. 1B) and the water treatment apparatus 50 (see FIG. 1B) Can be introduced. At this time, the MEG mixed fluid contains a small amount of water, MEG, and solute salt.

The heat exchanging unit 160 may be provided as a distillation tower for evaporating moisture in the MEG mixed fluid, and may be used to evaporate moisture by a distillation method. The fluid that has passed through the ejector 140 is heated by the heater 150 and the heat exchanger 160 heats the MEG mixed fluid by using the fluid (for example, a stream of low pressure and high temperature) . The fluid passing through the ejector 140 and flowing into the heat exchanging unit 160 may contain the MEG gas component recovered from the vacuum receiver 130. The MEG gas component may be supplied to the rejection unit 110 through the heat exchanger 160, thereby effectively reducing the MEG loss.

Specifically, the breaking point of moisture contained in the MEG mixed fluid is 100 ° C at atmospheric pressure, and the breaking point of the MEG is about 198 ° C. Even when employed, the break of salt is much higher than MEG. The heat exchanger 160 can heat the MEG mixed fluid at 100 ° C. to break the moisture, thereby minimizing moisture evaporation. At this time, the heat exchanger 160 can repeatedly evaporate moisture through multi-stage distillation.

At this time, a part of the high concentration MEG mixed fluid extracted by the heat exchanging unit 160 is supplied to the desorizing unit 110 through the second supply line L2 to perform the desalting work contained in the MEG mixed fluid.

When applied to the entire treatment mode, the remaining portion of the MEG mixed fluid through the above-described heat exchanging portion 160 is sent to the water treatment device 30 (see Fig. 1 (a)) for moisture removal through the discharge line L3 .

The remaining part of the MEG mixed fluid passing through the above-described heat exchanging unit 160, when applied to some of the treatment methods, is mixed with the MEG mixed through the water treatment unit 50 (see Fig. 1 (b)) through the discharge line L3 It can join the flow of the fluid.

On the other hand, the moisture evaporated by the heat exchanging unit 160 may be returned to the heat exchanging unit 160 as a reflux through the liquefier 170 and the reflux drum 180, and the remainder may be discharged.

At this time, a part of the water liquefied by the liquefier 170 through the fluid supply line L4 may be introduced into the inlet of the ejector 140 through the reflux drum 180 to provide a fluid for forming the vacuum state.

By using the fluid supplied through the fluid supply line L4 as the working fluid of the ejector 140, the operation efficiency of the post-treatment apparatus 100 for salt removal can be improved.

The foregoing has shown and described specific embodiments. However, it is to be understood that the present invention is not limited to the above-described embodiment, and various changes and modifications may be made without departing from the scope of the technical idea of the present invention described in the following claims It will be possible.

110: defatted 120: cooler
130: Vacuum receiver 140: Ejector
150: exhaust pump 160: heat exchanger
170: liquefier 180: reflux drum
L1: first supply line L2: second supply line
L3: discharge line L4: fluid supply line

Claims (3)

Deionization to remove salts by evaporating MEG from the MEG mixed fluid in a vacuum depressurized state;
A cooler for cooling the evaporated MEG;
A vacuum receiver disposed downstream of the cooler;
And an ejector for rapidly ejecting the fluid introduced from the inlet side toward the outlet so as to recover the gas in the vacuum receiver and to bring the vacuum receiver and the defatting unit constituting the front end thereof into a vacuum state. The method according to claim 1,
A heater for heating the fluid that has passed through the ejector,
A heat exchange unit for performing heat exchange between the MEG mixed fluid in which MEG, salt, and water are mixed and the heated fluid to evaporate moisture in the MEG mixed fluid,
A first supply line connecting the ejector, the heater, and the heat exchanger, the fluid passing through the ejector to the heat exchanger through the heater,
Further comprising a second supply line connecting the heat exchanger, the heater and the rejection, and providing the MEG mixed fluid with moisture evaporated by the heat exchange to the rejection of the salt. 3. The method of claim 2,
A liquefier for liquefying the water evaporated by the heat exchange,
A reflux drum provided downstream of the liquefier,
Further comprising a fluid supply line connecting the heat exchanger, the liquefier, the reflux drum and the ejector, and introducing a part of the liquefied moisture from the reflux drum toward the ejector inlet to provide the fluid for the vacuum state formation. Removal device.

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