KR101777119B1 - Apparatus for removing moisture from natural gas and the method for removing moisture from natural gas by using the same - Google Patents

Abstract

The apparatus for removing moisture of natural gas according to the present invention comprises: a mixing unit for mixing a raw material gas and methanol to produce a pretreatment gas; A temperature lowering part for cooling the pretreatment gas introduced from the mixing part; An absorber forming a rich absorbent including a first exhaust gas from which the cooled pretreatment gas is contacted with an absorbent to remove water and a moisture absorbent; And a regeneration unit for separating moisture from the rich absorbent introduced from the absorbing unit to form a regenerated absorbent and a second exhaust gas containing moisture, wherein the absorbent is mono ethylene glycol do.

Description

BACKGROUND OF THE INVENTION Field of the Invention [0001] The present invention relates to an apparatus for removing water from a natural gas,

The present invention relates to a device for removing moisture of natural gas and a method for removing moisture of natural gas using the same.

Moisture in natural gas corrodes pipes, valves and equipment during transport and storage, and damages the equipment by creating hydrates. Particularly in the liquefaction process of a liquefied natural gas plant, moisture condenses and seriously damages the equipment, so moisture in the natural gas must be removed to a low concentration.

In the water removal process, there is a method of adsorbing water vapor using a hygroscopic liquid material or a dewatering solid material, and a method of condensing water vapor by compression or cooling.

Among them, the method using a hygroscopic solvent mainly uses tri-ethylene glycol as a water absorbent, but in this case, a large amount of energy is required for the regeneration section, and the water absorption capacity is somewhat low.

Therefore, there is a need for a device for removing moisture of natural gas, which can reduce energy consumption, is excellent in water absorption ability, and can reduce the amount and volume of the absorbent.

Prior art related to this is disclosed in Korean Patent Publication No. 2006-0116325.

It is an object of the present invention to provide a moisture removal device for natural gas which can reduce energy consumption and is excellent in water absorption efficiency and a method for removing moisture of natural gas using the same.

Another object of the present invention is to provide a moisture removal device for natural gas which can reduce the amount of the water absorbent and reduce the device size, and a method for removing moisture of natural gas using the same.

It is still another object of the present invention to provide a device for removing moisture of natural gas which can increase the number of separation stages of the regeneration section and a method for removing moisture of natural gas using the device.

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention relates to an apparatus for removing water from a natural gas.

In one embodiment, the apparatus for removing moisture of natural gas includes a mixing section for mixing the raw material gas and methanol to form a pretreatment gas, a temperature lowering section for cooling the pretreatment gas introduced from the mixing section, An adsorbent which forms a rich absorbent including a first exhaust gas that has been removed by contact with moisture and a moisture absorbent; and a second absorbent that separates moisture from the rich absorbent introduced from the absorbent, And a regeneration section for forming an exhaust gas, wherein the absorbent is mono ethylene glycol.

The cooled pretreatment gas may have a temperature of -10 ° C to 5 ° C.

The mixing part may be prepared by mixing 0.01 to 0.09 parts by weight of methanol with respect to 100 parts by weight of the raw material gas and the raw material gas.

The raw material gas may be introduced into the mixing part at a temperature of 25 ° C to 40 ° C and a pressure of 60 bar to 70 bar.

The regeneration section may have 2 to 12 theoretical separation stages.

In another embodiment, the natural gas moisture removing apparatus may further include a first heat exchanger for exchanging heat between the rich absorbent discharged from the absorption section and the regenerated absorbent discharged from the regeneration section.

The natural gas moisture removing apparatus includes a decompression valve for decompressing the rich absorbent discharged from the absorption unit and a third exhaust gas containing hydrocarbon gasified from the decompressed rich absorbent and a rich absorbent from which the hydrocarbon is removed And may further include a storage unit.

The natural gas water removing device may further include a replenishing portion for replenishing the regenerated absorbent with mono ethylene glycol.

The apparatus for removing moisture of natural gas may further include a pump for introducing the regenerated absorbent discharged from the regeneration section into the absorbing section and a cooler for cooling the temperature of the regenerated absorbent to 35 ° C to 50 ° C.

The apparatus for removing moisture of natural gas includes a condenser for condensing a second exhaust gas containing the moisture discharged from the regeneration unit, and a condenser for separating mono ethylene glycol from the condensed second exhaust gas, And a gas-liquid separator supplied to the regeneration section.

The natural gas water removing apparatus may further include a boiler for supplying heat to the bottom liquid flowing from the regeneration unit and forming regenerable absorbent and bottom bottom vapor.

The natural gas water removing device may be a device for mixing a stripping gas into the bottom liquid.

The stripping gas may comprise at least one of a first offgas and a nitrogen gas.

In another embodiment, the temperature lowering portion may be a second heat exchanger of the extracting portion that performs a process of extracting natural gas.

The temperature drop may include propane or propylene refrigerant.

Another aspect of the present invention relates to a method for removing water from natural gas.

The method for removing water from a natural gas includes the steps of generating a pretreatment gas by mixing a raw material gas and methanol, cooling the pretreatment gas, contacting the cooled pretreatment gas with an absorbent to remove moisture from the first exhaust gas, Forming a rich absorbent comprising the combined absorbent, separating moisture from the rich absorbent to form a second absorbent comprising a regenerable absorbent and moisture, the absorbent being selected from the group consisting of mono ethylene glycol ) Is a method for removing water from natural gas using the natural gas water removal device.

The present invention relates to a device for removing moisture of natural gas, which can reduce energy consumption and water absorption efficiency, reduce the amount of water absorbent and apparatus size, and increase the number of separation stages of the regeneration section, and It has an effect of providing a method for removing moisture of natural gas.

1 is a conceptual diagram schematically showing an apparatus for removing moisture of natural gas according to an embodiment of the present invention.
2 is a conceptual diagram schematically showing an apparatus for removing moisture of natural gas according to another embodiment of the present invention.
3 is a conceptual view schematically showing an apparatus for removing moisture of natural gas according to another embodiment of the present invention.

Embodiments of the present application will now be described in more detail with reference to the accompanying drawings. However, the techniques disclosed in this application are not limited to the embodiments described herein but may be embodied in other forms. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the width, thickness, and the like of the components are enlarged in order to clearly illustrate the components of each device. In addition, although only a part of the components is shown for convenience of explanation, those skilled in the art can easily grasp the rest of the components. It is to be understood that when an element is described above as being located above or below another element, it is to be understood that the element may be directly on or under another element, It means that it can be done. It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit and scope of the invention. In the drawings, the same reference numerals denote substantially the same elements.

As used herein, "theoretical separation number" means the maximum separation factor at which the temperature of the regeneration section does not exceed 200 [deg.] C using PRO / II PROVISION Version 9.2.1 of INVENSYS, The SRKM (SRK-Modified Panagiotopoulos-Reid) equation of state is applied to the equations with the mixed rule proposed by Panagiotopoulos and Reid. The parameters are given in Table 1 and Table 2, do.

One aspect of the present invention relates to an apparatus for removing water from a natural gas.

Hereinafter, an apparatus for removing moisture of natural gas according to one embodiment of the present invention will be described with reference to FIG. 1 is a conceptual diagram schematically showing an apparatus for removing moisture of natural gas according to an embodiment of the present invention.

1, the apparatus 10 for removing moisture of natural gas according to an embodiment includes a mixing section 100 for mixing a raw material gas 90 and methanol 95 to form a pretreatment gas 110, A temperature lowering part 200 for cooling the pretreatment gas 110 introduced from the unit 100, a first exhaust gas 320 having moisture removed by bringing the cooled pretreatment gas 210 into contact with the absorbent, The absorbent 300 forming the rich absorbent 310 containing the absorbent that is absorbed by the absorbent 300 and the absorbent 310 absorbed from the absorbent 300 to separate the moisture from the regenerated absorbent 410, 2 exhaust gas 420, wherein the sorbent is mono ethylene glycol. ≪ RTI ID = 0.0 >

The natural gas water removal apparatus 10 of the present invention applies mono ethylene glycol as an absorbent. Monoethylene glycol has a lower breaking point than tri-ethylene glycol used as a conventional absorbent, and the water removal efficiency can be increased by lowering the temperature of the raw material gas and the temperature of the absorption part. Further, the temperature of the steam used in the regeneration unit 400 can be lowered, and the energy supplied to the natural gas water removal apparatus can be remarkably lowered. In addition, mono ethylene glycol has a higher water absorption than tri-ethylene glycol, has excellent water absorption efficiency, and has an advantage that the amount of the absorbent and the size of the device can be reduced.

The raw material gas 90 may be introduced into the mixing section 100 at a temperature of 25 ° C. to 40 ° C. and a pressure of 60 bar to 70 bar, specifically, a temperature of 30 ° C. to 38 ° C. and a pressure of 65 bar to 68 bar. The water removal efficiency of the natural gas water removal device is excellent in the above range.

The apparatus 10 for removing moisture of natural gas according to the present invention applies mono ethylene glycol having a low boiling point as an absorbent to improve energy saving and water removal rate and performs a water absorption process at low temperature and high pressure The mixed portion 100 forms the pretreatment gas 110 by mixing the raw material gas 90 and the methanol 95 so that the gas hydrate is formed into a gas hydrate Can be prevented.

Concretely, the mixing part 100 may be mixed with 0.01 to 0.09 part by weight, specifically 0.01 to 0.05 part by weight, of methanol 95 with respect to 100 parts by weight of the raw material gas 90 and the raw material gas. Within the above range, the balance between the inhibition of the production of gas hydrate in the raw material gas and the yield of the natural gas is excellent.

The temperature lowering part 200 cools the pretreatment gas 110 discharged from the mixing part 100 and flows into the absorption part 300 so that moisture can be absorbed at a low temperature. The temperature drop may include propane or propylene refrigerant.

Specifically, the temperature lowering part 200 can cool the pretreatment gas to -10 캜 to 5 캜, specifically, -7 캜 to 0 캜. In the above-mentioned range, the balance between the reduction of the supply energy and the yield of the natural gas of the natural gas water removal device is excellent.

The absorbing portion 300 contacts the absorbent with the cooled pretreatment gas 210 to form a rich absorbent including a moisture absorbed first absorbent and a moisture absorbent. Particularly, in the present invention, mono ethylene glycol is used as the absorbent, and the pretreatment gas 210 is supplied to the absorber 300 at a temperature of -10 ° C to 5 ° C, specifically, at a low temperature of -7 ° C to 0 ° C It is possible to keep the temperature of the absorption part at a lower level and to save energy supply of the moisture removal device of the natural gas.

The temperature of the absorber 300 may be 25 ° C. to 40 ° C., the pressure 60 bar to 70 bar, specifically the temperature 30 ° C. to 38 ° C., the pressure 65 bar to 68 bar, for example, Lt; / RTI >

The absorbing part 300 bonds the moisture with mono ethylene glycol and then discharges the rich absorbent 310 containing the moisture-removed first exhaust gas 320 and moisture-absorbent absorbent. The discharge can be through a pipe and connected to an inlet, but is not limited thereto.

The apparatus 10 for removing moisture of natural gas according to the present invention applies mono ethylene glycol as an absorbent and has a water absorption process at a low temperature, and is excellent in water removal rate. Specifically, the moisture content of the first off-gas 320 may be from 0.5 ppm to 15 ppm, specifically from 1 ppm to 7 ppm.

The first off-gas 320 may be introduced into another process, but is not limited thereto. For example, the first off-gas may be introduced into an extracting section for extracting natural gas.

The rich absorbent 310 discharged from the absorbing part 300 flows into the regeneration part 400.

The regeneration unit 400 separates moisture from the rich absorbent 310 and regenerates the absorbent. The regeneration unit 400 can maintain a constant pressure for water separation. The pressure of the regeneration section 500 may be, for example, 0.2 bar to 1.5 bar, specifically 0.3 bar to 1.2 bar. In particular, by applying mono ethylene glycol as the absorbent, the regeneration section can keep the temperature low. The fact that the temperature of the regeneration section can be kept low means that the temperature of the steam used in the boiler of the regeneration section can be lowered and the total energy supplied to the moisture removal device of the natural gas can be reduced. Also, the regeneration section may be formed as two or more separation stages. As the number of separation stages increases, the regeneration rate of the absorbent increases, while a higher temperature is required in the regeneration section, thereby increasing the energy consumption of the boiler. Therefore, the fact that the temperature of the regeneration section is low means that the regeneration section can be designed with a larger number of separation stages without increasing the energy consumption, thereby further increasing the regeneration rate of the absorbent. For example, the theoretical separation number of the regeneration section may be designed as 2 to 12 stages, specifically, 6 to 12 stages of separation stages. This means that when the efficiency of the separation stage is 33%, the separation stage of the regeneration section of the actual natural gas moisture removal apparatus can be applied in 6 to 36 stages, specifically 18 to 36 stages.

Specifically, the temperature of the regeneration unit 400 may be 100 ° C to 250 ° C, specifically 150 ° C to 200 ° C. In the above range, the energy supplied to the water absorbing device can be reduced, and the regeneration section can be designed in more stages, thereby improving the regeneration efficiency.

The regeneration unit 400 separates moisture to regenerate the absorbent, and then discharges the regenerated absorbent and the second exhaust gas 420 containing the water and the regenerated absorbent 410. [

The regenerated absorbent 410 may enter the absorber 300 again and may combine with the moisture of the cooled pretreatment gas 210 to remove moisture from the cooled pretreatment gas.

The second exhaust gas 420 containing moisture separated from the rich absorbent 310 may be discharged to the outside of the natural gas moisture removal device.

Hereinafter, an apparatus for removing moisture of natural gas according to another embodiment of the present invention will be described with reference to FIG. 2 is a conceptual diagram schematically showing an apparatus for removing moisture of natural gas according to another embodiment of the present invention.

2, the apparatus for removing moisture of natural gas 20 includes a first absorbent 310 and a second absorbent 410, which exchange heat between the rich absorbent 310 discharged from the absorbing unit 300 and the regenerated absorbent 410 discharged from the regeneration unit 400, And may further include a heat exchanger 500.

The absorber 300 is operated at about 30 ° C to 40 ° C and the regeneration unit 400 is operated at about 150 ° C to 250 ° C to have a temperature difference between the absorber and the regeneration unit. Therefore, it is necessary to increase the temperature of the rich absorbent 310 discharged from the absorber 300 and to lower the temperature of the regenerant absorbent 410 discharged from the regeneration unit 400. In the first heat exchanger 500, The regenerated absorbent at a temperature can transfer heat to a rich absorbent at a lower temperature. The natural gas water removal apparatus 20 includes the heat exchanger 500, so that the energy efficiency can be increased.

The natural gas water removal device 20 includes a decompression valve 580 for decompressing the rich absorbent 310 discharged from the absorption part 300 and a decompression valve 580 for decompressing the rich absorbent 310 discharged from the decompressed rich absorbent 590, 3 exhaust gas 620 and a rich absorbent 610 from which the hydrocarbon has been removed.

Specifically, the pressure of the depressurized rich absorbent 590 may be from 3 bar to 10 bar, specifically from 5 bar to 6 bar. When the pressure of the rich absorbent 590 is lowered, the contained hydrocarbons can be separated into gases, which can be removed to increase the purity of the absorbent. In addition, the rich absorbent has the advantage that it can be flowed into the regeneration section by reducing the pressure difference with the regeneration section 400 operated at a pressure of about 0.2 bar to 1.5 bar through a reduced pressure.

The third exhaust gas 620 containing hydrocarbon discharged from the storage unit 600 may be discharged to the outside or may be collected through a trapper and flow into another process, but the present invention is not limited thereto.

The rich absorbent 610 from which the hydrocarbon discharged from the storage part 600 is removed flows into the regeneration part 400 and separates moisture from the rich absorbent to regenerate the absorbent.

The natural gas water removal apparatus 20 may further include a replenishing unit 700 that replenishes the regenerated absorbent 410 with mono ethylene glycol. In the water removal apparatus 20, the absorbent absorbs moisture and then reuses the moisture in the regeneration unit. However, in the water removal process, the first exhaust gas 320, the second exhaust gas 420, And the third exhaust gas 620, as shown in FIG. At this time, the replenishing unit 700 replenishes (695) mono ethylene glycol to maintain the amount of the absorbent required for the natural gas water removal apparatus to be constant. For example, the replenishing unit 700 may include a measuring unit (not shown) capable of measuring the amount of the absorbent of the natural gas water removing apparatus and a measuring unit (not shown) And a control unit (not shown) for controlling the supplementation (695) of mono ethylene glycol.

The natural gas water removal apparatus 20 includes a pump 720 for introducing the regenerated absorbent 410 discharged from the regeneration unit 400 into the absorption unit 300 and a regeneration unit And may further include a cooler 750 for cooling to 50 ° C.

The pump 720 may provide pressure to allow the regenerated absorbent 410 to enter the absorber 300.

The cooler 750 cools the regenerated absorbent 410 supplied to the absorber 300 and controls the absorber 300 to operate at about 30 ° C to 40 ° C so that the monoethylene glycol is adsorbed in a suitable environment .

The natural gas desalination device 20 includes a condenser 800 for condensing a second exhaust gas 420 containing the moisture discharged from the regeneration unit 400 and a second exhaust gas 420 for condensing the condensed second exhaust gas 420 Liquid separator 850 separating the mono ethylene glycol 860 from the regeneration unit 400 and supplying it to the regeneration unit 400.

The mono ethylene glycol may be discharged together with the regenerant 400 in the process of discharging water separated from the rich absorbent and the condenser 800 and the gas-liquid separator 850 may be separated from the mono ethylene glycol glycol may be reintroduced into the regeneration unit 400 so as to be reused. The second exhaust gas 870 from which the mono ethylene glycol 860 is separated may be discharged to the outside of the natural gas water removal device. The second exhaust gas 870 from which the mono ethylene glycol is separated may be mostly water.

The natural gas moisture removal apparatus 20 further includes a boiler for supplying heat to the bottom reservoir 890 flowing from the regeneration unit 400 to form the regenerable absorbent 410 and the bottoms vapor 960 .

Specifically, the thermal energy of the boiler is supplied to the steam 950, the low-temperature column bottom liquid 890 absorbs heat from the boiler 900, and the regenerator 400 ). ≪ / RTI > The top reservoir 890 can be a regenerated sorbent in which moisture is separated from the rich sorbent.

The natural gas moisture removal device 20 of the present invention has an advantage that the boiler 900 can be operated at a relatively low temperature of 150 ° C to 200 ° C, specifically 150 ° C to 170 ° C, by applying monoethylene glycol as an absorbent have.

The boiler 900 may be operated under reduced pressure to lower the boiling point of the bottom liquid 890 so that the boiler 900 can operate at the above temperature. Specifically, the decompression operation may be operated at a pressure of 0.2 bar to 0.9 bar, specifically 0.25 bar to 0.5 bar. In the above range, the boiler can be operated at a low temperature, and the energy efficiency of the natural gas water removal device can be increased.

The natural gas water removal device may be a device for mixing the stripping gas 990 with the bottom liquid 890. The stripping gas is a gas having a low breaking point and can be partially dissolved in the bottom liquid to lower the boiling point of the bottom liquid. Thus, the stripping gas has an advantage that the energy efficiency of the natural gas moisture removing apparatus can be increased. Specifically, the stripping gas may include at least one of a first exhaust gas and a nitrogen gas.

Hereinafter, an apparatus for removing moisture of natural gas according to another embodiment of the present invention will be described with reference to FIG. 3 is a conceptual view schematically showing an apparatus for removing moisture of natural gas according to another embodiment of the present invention.

Referring to FIG. 3, the temperature lowering part may be a second heat exchanger 201 of the extraction unit 1000 that performs a process of extracting natural gas. The temperature lowering part serves to lower the temperature of the raw material gas. By utilizing the cooling energy from the second heat exchanger 201 in the process of extracting the natural gas, the energy supplied to the moisture removing device of the natural gas is saved, Can be further increased.

The process for producing natural gas may include a process for extracting natural gas, which may be performed in the extractor 1000 including the second heat exchanger 201 and the deethanizer. In this case, the natural gas water removal device 30 can cool the pretreatment gas with the second heat exchanger included in the extraction unit 1000 without separately designing the temperature lowering part.

Specifically, the extraction unit 1000 includes an inclined separator (not shown) for separating the introduced gas into vapor, oil and a small amount of water, a deethanizer (not shown) for extracting hydrocarbon from the gas phase, And a heat exchanger (201).

The second heat exchanger 201 may include, for example, the first off-gas 320, the liquefied natural gas extracted from the first off-gas by a decanter (not shown), the gas exiting the de- And the heat of the pretreatment gas 110 may be exchanged.

In another embodiment, the temperature lowering portion may further comprise a propane or propylene refrigerant.

Another aspect of the present invention relates to a method for removing water from natural gas.

In one embodiment, the method for removing water from natural gas includes the steps of mixing a raw material gas and methanol to produce a pretreatment gas, cooling the pretreatment gas, contacting the cooled pretreatment gas with an absorbent to remove water Forming a rich absorbent comprising an absorbent combined with exhaust gas and moisture, separating moisture from the rich absorbent to form a second absorbent comprising a regenerable absorbent and moisture, wherein the absorbent is selected from the group consisting of monoethylene glycol (mono ethylene glycol), which is a method for removing moisture of natural gas.

The method for removing moisture of the natural gas may be substantially the same as that described in the apparatus for removing moisture of natural gas of the present invention.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

The contents not described here are sufficiently technically inferior to those skilled in the art, and a description thereof will be omitted.

Example

Example  One

0.02 parts by weight of methanol was mixed with 100 parts by weight of the raw material gas and the raw material gas. The mixture was cooled to -2.0 DEG C and introduced into the absorption part. Mono ethylene glycol (mass flow rate: 4,000 kg / hr) , And the regeneration unit designed a natural gas water removal apparatus for purifying 99.5 wt% of the rich absorbent.

Comparative Example  One

Ethylene glycol was used as the absorbent at 4,000 kg / hr (mass flow rate) of triethylene glycol, and the regeneration section used a natural gas moisture removal device for purifying 99.5% by weight of the rich absorbent Respectively.

Assessment Methods

(1) Moisture content (ppm) of the process gas: The moisture content in the gas discharged from the absorption part in the natural gas water removal apparatuses of Examples and Comparative Examples was measured according to INVENSYS PRO / II PROVISION Version 9.2 As a program, the SRKM (SRK-Modified Panagiotopoulos-Reid) state equation was used. The SRKM state equations are used together with the mixing rule proposed by Panagiotopoulos and Reid in the SRK state equations. The parameters of each component are calculated by applying the values shown in Table 1 and Table 2 for the mixing rule.

(2) Absorbent loss ratio (% by weight): The weight of the absorbent discharged from the absorber, the regeneration unit and the storage unit with respect to the weight of the absorbent was measured using the PRO / II PROVISION Version 9.2.1 program of INVENSYS, SRKM -Modified Panagiotopoulos-Reid) state equation was used. The SRKM state equations are used together with the mixing rule proposed by Panagiotopoulos and Reid in the SRK state equations. The parameters of each component are calculated by applying the values shown in Table 1 and Table 2 for the mixing rule.

 (3) Number of theoretical separation stages: The maximum separation number at which the temperature of the regeneration section does not exceed 200 ° C is measured by the PRO / II PROVISION Version 9.2.1 program of INVENSYS, the SRKM (SRK-Modified Panagiotopoulos-Reid) State equations were used. The SRKM state equations are used together with the mixing rule proposed by Panagiotopoulos and Reid in the SRK state equations. The parameters of each component are calculated by applying the values shown in Table 1 and Table 2 for the mixing rule.

 (4) Temperature of regenerator bottom (° C) and pressure (bar): The regenerator bottom temperature of the natural gas water removal device of the examples and comparative examples was measured by the PRO / II PROVISION Version 9.2.1 program of INVENSYS , And SRKM (SRK-Modified Panagiotopoulos-Reid) state equations. The SRKM state equations are used together with the mixing rule proposed by Panagiotopoulos and Reid in the SRK state equations. The parameters of each component are calculated by applying the values shown in Table 1 and Table 2 for the mixing rule.

Panagiotopoulos  and Reid's Mixed Rule

,

a _i : Interaction parameter between i components

_{Tc, i} : the critical temperature (K) for the i component,

P _{c, i} : Critical pressure (atm) for i component,

a _j : Interaction between j components Parameters:

_{Tc, j} : the critical temperature (K) for the j component,

P _{c, j} : Critical pressure (atm) for the j component,

R: ideal gas constant: 0.08206 atm · L / mol · K

a _ij : Interaction parameter between i and j components

k _ij , k _ji : correction factor of interaction parameter between i and j components

x _i : mole fraction of i component in liquid phase

ingredient

i j A _ij B _ij C _ij A _ji B _ji C _ji methane MEG 0.3872 -125.03 One -0.00811 114.26 0 ethane MEG 0.4337 -126.64 0.3 0.1345 -17.16 0 Propane MEG -0.3338 99.53 0.5 0.3323 -97.3 0 Isobutane MEG 0.1 0 One 0.21 0 0 Normal butane MEG 0.1 0 One 0.21 0 0 Isopenta MEG 0.3384 -47.56 One 0.18 0 0 Normal penta MEG 0.3384 -47.56 0 0.18 0 0 water MEG -0.0198 -10.6 4.5153 -0.1436 22.69 0

ingredient

i j A _ij B _ij C _ij A _ji B _ji C _ji methane TEG 0.3894 -36.34 0.7012 0.5446 -92.67 0 ethane TEG 0.2244 8.43 0.7012 0.5446 -92.67 0 Propane TEG 0.322 -38.85 0.2385 0.2743 -30.28 0 Isobutane TEG 0.1 0 One 0.21 0 0 Normal butane TEG 0.1 0 One 0.21 0 0 Isopenta TEG 0.3384 -47.56 One 0.18 0 0 Normal penta TEG 0.3384 -47.56 One 0.18 0 0 water TEG -0.0836 -53.81 0 -0.1765 -28.4 0

Example 1 Comparative Example 1 Absorbent flow rate (kg / hr) 4,000 4,000 Water content (ppm) of the process gas 0.99 24.3 Absorbent loss ratio (% by weight) 0.01 0.02 Lower temperature of regenerator (℃) 163.0 192.1 Lower part of regenerating part (bar) 0.40 0.40 Reproducing part Theoretical separation number (stage) 10 10

As shown in Table 3, Example 1, in which mono ethylene glycol is used as an absorbent, is excellent in water absorption efficiency, so that the moisture content of the process gas is low and the water absorption process can be performed at a low temperature , The loss rate of the absorbent and the temperature of the bottom of the regeneration tower can be lowered. In particular, lowering the temperature of the lower part of the regeneration tower means not only the energy supplied from the boiler to the water absorption apparatus can be reduced, but also the regeneration tower can be designed with more stages, thereby improving the regeneration rate of the absorbent.

Example  2

A raw material gas of 201,285 kg / hr containing 0.11% by weight of water was introduced into an absorber (monoethylene glycol ( mono ethylene glycol), and the amount (kg / hr) thereof is shown in Table 4 below.

Comparative Example  2

(Raw material gas containing 0.11% by weight of water and 201,285 kg / hr of the raw material gas) was treated with an absorbent (triethylene glycol) so that the moisture contained in the gas discharged from the absorption part was 25 ppm by using the natural gas water removal device of Comparative Example 1. [ And the amount (kg / hr) thereof is shown in Table 4 below.

Example 2 Comparative Example 2 Amount of absorbent (kg / hr) Under 1,860 More than 3,000

As shown in Table 4, it can be seen that the embodiment using mono ethylene glycol as the absorbent can significantly reduce the amount of the absorbent as compared with the comparative example. This has the advantage of reducing the sizing of the water absorbing device.

While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood that the invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is to be understood, therefore, that the embodiments described above are intended to be illustrative in all respects and not restrictive.

The present invention relates to a water absorbing device for absorbing moisture in a water absorbing device and a method for producing the same, The first exhaust gas and the second exhaust gas are supplied to the first and second heat exchangers and the first and second heat exchangers, respectively. 620: third exhaust gas, 695: mono ethylene glycol, 700: replenishing portion, 720: pump, 750: cooling portion, 760: water absorbing agent, 600: storage portion, 610: hydrocarbon absorbent rich absorbent, 850: gas-liquid separator, 860: mono ethylene glycol, 870: second exhaust gas from which monoethylene glycol is removed, 890: bottom liquid, 900: boiler, 950: steam , 960: head bottom steam, 990: stifling gas, and 1000:

Claims (16)

A mixing part for mixing a raw material gas and methanol to form a pretreatment gas;
A temperature lowering part for cooling the pretreatment gas introduced from the mixing part;
An absorber forming a rich absorbent including a first exhaust gas from which the cooled pretreatment gas is contacted with an absorbent to remove water and a moisture absorbent; And
And a regeneration section for separating moisture from the rich absorbent introduced from the absorbing section to form a regenerated absorbent and a second exhaust gas containing moisture,
The absorbent is mono ethylene glycol,
Wherein the cooled pretreatment gas has a temperature of -10 ° C to 5 ° C.
delete The apparatus for removing moisture of natural gas according to claim 1, wherein the mixing unit mixes 0.01 to 0.09 parts by weight of methanol with respect to 100 parts by weight of the raw material gas and the raw material gas.
The apparatus for removing moisture of natural gas according to claim 1, wherein the raw material gas flows into the mixing portion at a temperature of 25 to 40 DEG C and a pressure of 60 to 70 bar.
The apparatus for removing moisture of natural gas according to claim 1, wherein the regeneration section has 2 to 12 theoretical separation stages.
The apparatus for removing moisture of natural gas according to claim 1,
Further comprising a first heat exchanger for exchanging heat between the rich absorbent discharged from the absorption section and the regenerant absorbent discharged from the regeneration section.
The apparatus for removing moisture of natural gas according to claim 1,
A pressure reducing valve for reducing the pressure of the rich absorbent discharged from the absorber; And
And a storage unit for forming a third exhaust gas containing hydrocarbon gasified from the decompressed rich absorbent and a rich absorbent from which the hydrocarbon is removed.
The apparatus for removing moisture of natural gas according to claim 1,
Further comprising a replenishing portion that replenishes the regenerated absorbent with mono ethylene glycol.
The apparatus for removing moisture of natural gas according to claim 1,
A pump for introducing the regenerant absorbent discharged from the regeneration section into the absorption section, and
Further comprising a cooler for cooling the temperature of the regenerating absorbent to 35 to 50 占 폚.
The apparatus for removing moisture of natural gas according to claim 1,
A condenser for condensing the second exhaust gas containing the moisture discharged from the regeneration section, and
And a gas-liquid separator for separating mono ethylene glycol from the condensed second exhaust gas and supplying the mono ethylene glycol to the regeneration unit.
The apparatus for removing moisture of natural gas according to claim 1,
And a boiler for supplying heat to the bottom liquid flowing from the regeneration unit to form a regenerable absorbent and a bottoms vapor.
12. The apparatus for removing moisture of natural gas according to claim 11,
And a stripping gas is mixed in the bottom liquid.
13. The apparatus of claim 12, wherein the stripping gas comprises at least one of a first off-gas and a nitrogen gas.
The apparatus according to claim 1, wherein the temperature-
Wherein the second heat exchanger is a second heat exchanger of an extraction unit that performs a process of extracting natural gas.
The apparatus of claim 1, wherein the temperature lowering portion comprises a propane or propylene refrigerant.
Mixing the raw material gas and methanol to produce a pretreatment gas;
Cooling the pretreatment gas;
Contacting the cooled pretreatment gas with an absorbent to form a rich absorbent comprising a first exhaust gas from which moisture has been removed and an absorbent having moisture incorporated therein;
Separating moisture from the rich absorbent to form a second absorbent containing a regenerated absorbent and moisture,
The method for removing moisture of natural gas according to any one of claims 1 to 15, wherein the absorbent is mono ethylene glycol.

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