KR101759101B1 - Process and apparatus of capturing carbon dioxide, recovering hydrogen from byproduct gas - Google Patents

Abstract

The present invention relates to a method of manufacturing an absorbent article, comprising the steps of: (1) supplying an absorbent into an absorbent filling space of an absorbent module; Injecting a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane (step 2); Adjusting the pressure in the absorption module so that carbon dioxide in the iron byproduct gas can be selectively dissolved in the absorbent (step 3); And separating and discharging the gas containing hydrogen absorbed in the absorbent and the absorbent dissolved in carbon dioxide (step 4), and a method for collecting carbon dioxide and recovering hydrogen from the steel by-product gas. The method and apparatus for collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention are simpler in process than the prior art through a hollow fiber separator and an absorbent, can be downsized, have a low installation cost, and have an operation cost. In addition, even in the case of water containing no water gas reaction (WGS) and other impurities, it is possible to separate carbon dioxide stably and recover the hydrogen, thereby reducing the burden of the pretreatment and providing high energy efficiency have.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for recovering carbon dioxide from a by-

More particularly, the present invention relates to a method for collecting carbon dioxide from a steel by-product gas, and more particularly, to a method for recovering hydrogen by removing carbon dioxide by contacting a steel byproduct gas supplied into a hollow fiber separation membrane with an absorbent, To a method and apparatus for capturing absorbed carbon dioxide.

Blast Furnace Gas (BFG) and Linz-Donawitz Converter Gas (LDG), which are kinds of seasonal byproduct gases, contain a large amount of carbon dioxide (CO ₂ ) and carbon monoxide (CO) have. The use of conventional by-product by-product gas has been used as a raw material gas for generating a heat source through combustion since there is no systematic conversion, separation and recovery method (Korean Patent Publication No. 10-2013-0002151).

In addition, some by-products such as Coke Oven Gas (COG) and Finex Off Gas (FOG) are also available. Since the steel by-product gas generated after combustion contains a large amount of carbon dioxide, it is necessary to secondarily remove carbon dioxide through an amine absorption method or the like.

At present, a method for producing hydrogen through a water-gas shift (WGS) process has been studied to efficiently use the byproduct gas of steel, and the additional reaction product is carbon dioxide. The temperature after the water gas shift reaction is generally 40 ° C or less, and water is removed using an adsorbent or the like as a pretreatment for separating carbon dioxide and hydrogen. At this time, absorption, adsorption, separation membrane method and the like can be used to remove carbon dioxide and to recover hydrogen after moisture removal.

However, in the case of the absorption method using ammonia-based absorbent, there is a disadvantage in that the energy consumption is large because it relies heavily on the thermodynamic equilibrium. In the case of the adsorption method, the amount of the adsorbent and other equipment It is difficult to realistically realize it.

In addition, the separation membrane method can reduce the energy consumption drastically and enables a dense structure. However, separation membranes using polymer membranes are difficult to use because of low hydrogen / carbon dioxide separation (<2), and inorganic pores having micropores (zeolite, Carbon, metal-organic skeleton (MOF), etc.), the separation efficiency is very low.

Furthermore, the hydrogen / carbon dioxide separation using palladium (Pd) membrane can achieve a high degree of separation, but the material is expensive and can be operated at a temperature of 400 ° C. or higher.

Accordingly, the present inventors have developed a method and apparatus for selectively recovering carbon dioxide having high solubility from by-product gas by contact with a gas-liquid contact, iron byproduct gas, and an absorbent through an absorbent circulating through the porous hollow fiber membrane to recover hydrogen , Thereby completing the present invention.

It is an object of the present invention to provide a method and apparatus for collecting carbon dioxide and recovering hydrogen from a steel by-product gas having improved energy efficiency.

In order to achieve the above object,

Supplying the absorbent into the absorbent filling space of the absorption module (step 1);

Injecting a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane (step 2);

Adjusting the pressure in the absorption module so that carbon dioxide in the iron byproduct gas can be selectively dissolved in the absorbent (step 3); And

And separating and discharging a gas containing hydrogen absorbed by the absorbent dissolved in the absorbent and carbon dioxide (step 4).

In addition,

housing; A hollow separator mounted in the housing; And an absorbent filling space defined by the outside of the hollow fiber membrane and the inside of the housing which constitute the hollow fiber membrane.

An absorbent supply part for supplying the absorbent into the absorbent filling space of the absorption module; And

And a gas supply part for supplying a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane of the absorption module, the carbon dioxide capture and hydrogen recovery device to provide.

Further,

Supplying the absorbent having dissolved carbon dioxide separated from the absorption module to the absorbent filling space of the degassing module (step a);

(B) discharging the gas inside the hollow fiber separator of the degassing module to the outside;

Adjusting the pressure in the degassing module so that the carbon dioxide dissolved in the absorbent can be degassed (step c);

(Step d) separating and discharging the carbon dioxide deasphalted absorbent and the degassed carbon dioxide.

The method and apparatus for collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention are simpler in process than the prior art through a hollow fiber separator and an absorbent, can be downsized, have a low installation cost and operation cost. In addition, even in the case of a gas containing water and other impurities after the water gas reaction (WGS), the carbon dioxide can be stably separated and the hydrogen can be recovered, thereby reducing the burden of the pretreatment and energy efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a graph showing gas compositions of blast furnace gas (BFG) and converter gas (LDG), which are steel byproduct gases, and gas composition when the gases are subjected to a water gas conversion process and a water removal process;
FIG. 2 is a schematic view showing an example of an absorption module in a carbon dioxide capture and hydrogen recovery apparatus from a steel by-product gas according to the present invention; FIG.
3 is a schematic view schematically showing an example of an absorption module and a degassing module in a carbon dioxide capture and hydrogen recovery apparatus from iron byproduct gas according to the present invention;
FIG. 4 is a schematic view schematically showing an example of an absorption module, a deaeration module and an absorbent degassing tank in a carbon dioxide capture and hydrogen recovery device from steel byproduct gas according to the present invention; FIG.
5 is a graph showing the hydrogen recovery rate and the carbon dioxide removal rate in Examples 1 and 2 according to the present invention.

The present invention

Supplying the absorbent into the absorbent fill space 102 of the absorption module 100 (step 1);

Injecting a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane 101 (step 2);

Adjusting the pressure in the absorption module so that carbon dioxide in the iron byproduct gas can be selectively dissolved in the absorbent (step 3); And

And separating and discharging a gas containing hydrogen absorbed by the absorbent dissolved in the absorbent and carbon dioxide (step 4).

2 to 4 schematically show an example of the hydrogen recovery apparatus and method according to the present invention,

Hereinafter, a method for collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention will be described in detail with reference to FIG. 2 to FIG.

First, in the method of collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention, step 1 is a step of supplying the absorbent into the absorbent filling space 102 of the absorption module 100.

In the step 1, the absorbent is supplied into the absorbent filling space 102 of the absorption module 100 so that the steel by-product gas and the absorbent can make gas-liquid contact.

The absorbent is supplied from the absorbent degassing tank 500 to the absorbent filling space through the absorbent feeder 200. At this time, the flow rate of the absorbent supplied to the absorber is controlled by the flow rate of the steel by- .

At this time, the flow rate of the absorbent supplied may be from 100 ml / min to 1000 ml / min when one absorption module is provided, and may be from 200 ml / min to 800 ml / min, The present invention is not limited thereto, and the flow rate may be changed by having an additional absorption module.

It is preferable that the absorbent is supplied from the lower end of the absorption module 100 and flows to the upper end of the absorption module after flowing through the absorbent filling space 102. However, May be supplied and discharged in the opposite direction, but the present invention is not limited thereto.

At this time, the absorbent does not pass into the hollow fiber separation membrane 101 of the absorption module, but can contact only the gas inside the hollow fiber separation membrane.

Next, in the method of collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention, step 2 is a step of separating the iron by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) And then injected into the inside.

In step 2, a steel by-product gas containing hydrogen and carbon dioxide is supplied into the hollow fiber of the hollow fiber separation membrane 101 so that gas-liquid contact with the absorbent supplied in step 1 can be performed.

The steel byproduct gas in step 2 may be supplied through the gas supply unit 700, and the supplied flow rate may be adjusted through the gas supply unit.

The flow rate of the steel byproduct gas supplied may be from 50 ml / min to 1000 ml / min, preferably from 100 ml / min to 500 ml / min. However, the flow rate of the steel by- It is not limited thereto.

The by-produced by-product gas is supplied into the hollow fiber separation membrane 101 through the gas supply unit 700. The supplied by-product gas diffuses into the pores of the hollow fiber separation membrane, Most of the carbon dioxide in the iron by-product gas is selectively dissolved. The remaining undissolved gas is discharged to the outside of the absorption module 100.

The iron byproduct gas of step 2 may contain 0.1 to 80 vol% of hydrogen, preferably 0.3 to 45 vol%.

In addition, the iron byproduct gas in step 2 may contain carbon dioxide in an amount of 0.1% by volume to 80% by volume, preferably 3% by volume to 50% by volume.

At this time, the steel by-product gas may further include nitrogen, carbon monoxide, water, oxygen, and the like.

The steel by-product gas of step 2 may be a steel by-product gas that has undergone a water-gas shift (WGS) process, wherein the steel by-product gas subjected to the water gas conversion is 15 volume% to 50 Vol% hydrogen, and preferably from 15 vol% to 40 vol% hydrogen.

However, the method of collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention can efficiently perform the step of separating carbon dioxide, which will be described later, even if it is a steel by-product gas containing moisture, Not necessary.

Further, the steel byproduct gas in which the water gas conversion step is performed may include 20 to 50 vol.% Carbon dioxide, and preferably 20 to 40 vol.% Carbon dioxide.

The water gas conversion is a process for generating hydrogen by reacting carbon monoxide included in blast furnace gas (BFG), linz-donawitz converter gas (LDG), etc., which are steel by-product gases, with steam again, As shown below.

<Reaction Scheme>

CO + H ₂ O ↔ CO ₂ + H ₂

In order to maximize the production of hydrogen, it is preferable to convert all the carbon monoxide to carbon dioxide and hydrogen by using this reaction. However, the carbon dioxide capture and hydrogen recovery device from the iron byproduct gas according to the present invention is a gas containing water and carbon monoxide It also has the advantage of collecting carbon dioxide and recovering hydrogen.

In addition, a water removal step may be further performed using an adsorbent or the like for the gas subjected to the water gas conversion reaction.

FIG. 1 shows an example of the compositional by-product gas, the by-product by-produced gas converted by the water-gas conversion, and the by-product gas by the water removal process after the water gas conversion.

In addition, in the step 2, the flow rate ratio of the iron byproduct gas and the absorbent may be 0.01 to 1, 0.05 to 1, and preferably 0.1 to 1, The present invention is not limited thereto.

Next, in the method for collecting carbon dioxide and recovering hydrogen from iron by-product gas according to the present invention, step 3 is a step of adjusting the pressure in the absorption module 100 so that carbon dioxide in the iron by-product gas can be selectively dissolved in the absorbent .

In step 3, the pressure in the absorption module 100 is adjusted so that carbon dioxide can be effectively dissolved as an absorbent.

However, since the solubility is not so high under ordinary atmospheric pressure, the pressures of the steel by-product gas and the absorbent in the absorption module 100 are controlled through the adsorbent pressure control unit and the gas pressure control unit, .

At this time, the pressure of the steel by-product gas in the absorption module may be 0.1 atm to 15 atm, preferably 0.5 atm to 10 atm, but is not limited thereto, so long as the pressure is such that carbon dioxide can be effectively dissolved in the absorbent.

Further, the pressure of the absorbent in the absorption module 100 may be 0.1 atm to 15 atm, preferably 0.5 atm to 10 atm, but is not limited thereto, so long as the pressure is such that carbon dioxide can be effectively dissolved in the absorbent.

Thus, even if the pressure in the absorption module 100 is increased, other gases in the by-product gas other than carbon dioxide are not dissolved in the absorbent, so that carbon dioxide can be effectively separated from the steel by-product gas.

However, if the pressure in the absorption module 100 exceeds 15 atm, the hollow fiber separator 101 may collapse. If the pressure is less than 0.1 atm, the carbon dioxide may not be effectively dissolved.

Next, in the method for collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention, step 4 is a step of discharging gas containing carbon dioxide-free absorbent and hydrogen not dissolved in the absorbent.

In the step 4, the hydrogen-containing gas and the absorbent are not dissolved in the absorbent, and the hydrogen can be easily recovered by separating and discharging the absorbent.

Further, the step (4) of degassing the carbon dioxide from the absorbent in which the carbon dioxide is dissolved in the step (4) (step 5) may be further included.

The absorbent separated in the step 4 may be transferred to and stored in the absorbent degassing tank 500. The pressure in the absorbent degassing tank may be atmospheric pressure or vacuum, but if the pressure in the absorbent is such that the carbon dioxide can be degassed, no.

At this time, the carbon dioxide dissolved in some of the absorbent can be deaerated and supplied to the inside of the hollow fiber separation membrane 101 of the absorption module 100.

Further, the step of supplying the absorbent, in which the carbon dioxide dissolved in the absorption module 100 is dissolved, to the absorbent filling space 302 of the degassing module 300 (step a); (B) discharging the gas inside the hollow fiber separation membrane 301 of the degassing module to the outside; Adjusting the pressure in the deaeration module so that carbon dioxide dissolved in the absorbent can be deaerated (step c); And separating and discharging the carbon dioxide-depleted absorbent and the degassed carbon dioxide (step d).

In step a, the absorbent having absorbed carbon dioxide through the absorption module 100 is supplied to the absorbent filling space of the degassing module 300, so that the carbon dioxide in the absorbent can be degassed.

It is preferable that the absorbent is supplied from the upper end of the absorption module 100 and flows into the absorbent filling space 302 of the deodorization module 300 and then discharged to the lower end of the deodorization module. The absorbent passing through the degassing module may be supplied and discharged in the opposite direction, but is not limited thereto.

At this time, the absorbent can not pass into the hollow fiber separation membrane 301 of the degassing module, but can contact only the gas inside the hollow fiber separation membrane.

The absorbent that has performed step a may be discharged to the outside of the degassing module 300 and then supplied to the absorption module 100 to be circulated.

In the step b, the inner gas of the hollow fiber separator 301 of the deaeration module 300 can be adjusted to a normal pressure or a vacuum state so that the gas can be discharged to the outside. However, the pressure is not limited thereto as long as the pressure is such that carbon dioxide can be degassed.

In the inner space of the hollow fiber separation membrane 301 in the step (b), carbon dioxide that has been degassed through the carbon dioxide dissolved in the absorbent may be supplied to the outside of the hollow fiber separation membrane, and carbon dioxide may be finally separated and discharged.

In the step c, the pressure in the deaeration module 300 is controlled so that the carbon dioxide dissolved in the absorbent can be effectively deaerated into the hollow fiber separation membrane 301 of the degassing module.

At this time, the pressure of the gas in the degassing module 300 and the pressure of the absorbent are adjusted through the first decompression pump 400.

At this time, the pressure of carbon dioxide, which is a gas in the degassing module 300, can be 0.01 atm to 2 atm, preferably 0.1 atm to 1.5 atm. However, if the carbon dioxide dissolved in the absorbent is a pressure capable of effectively degassing, It does not.

In the step d, the carbon dioxide-depleted absorbent and the degassed carbon dioxide are separated, and the carbon dioxide-depleted absorbent can be supplied again to the absorption module 100 and circulated.

Further, the method may further include a step (step 6) of purifying hydrogen (H ₂ ) using the gas containing hydrogen separated in step 4 using a gas separation membrane.

In the step 6, nitrogen is separated from the hydrogen-containing gas of the step 4 through the gas-liquid separator to finally purify the hydrogen. At this time, the gas separation membrane used for the nitrogen separation can be a well-known one developed by a person skilled in the art.

In addition,

housing; A hollow fiber separation membrane (101) mounted in the housing;

An absorption module (100) comprising an absorbent filling space (102) defined by the outside of the hollow fiber membrane and the inside of the housing, which constitute the hollow fiber membrane;

An absorbent supply part (200) for supplying the absorbent into the absorbent filling space of the absorption module; And

And a gas supply part (700) for supplying a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane of the absorption module. Thereby providing a recovery device.

2 to 4 schematically show an example of a carbon dioxide capture and hydrogen recovery apparatus from iron byproduct gas according to the present invention,

Hereinafter, referring to FIG. 2 to FIG. 4, the carbon dioxide capture and hydrogen recovery apparatus from the iron byproduct gas according to the present invention will be described in detail.

The apparatus for collecting carbon dioxide and recovering hydrogen from iron byproduct gas according to the present invention comprises: a housing for preventing and protecting leakage of an internal fluid; A porous hollow fiber membrane 101 mounted in the housing; And an absorbent module (100) including an absorbent filling space (102) defined by the outside of the hollow fiber membrane and the inside of the housing forming the hollow fiber membrane,

An absorbent supply part (200) for supplying the absorbent into the absorbent filling space of the absorption module; And a gas supply unit 700 for supplying a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane of the absorption module.

At this time, the surface of the hollow fiber separation membrane 101 is in the form of fine pores, the diffusion of the absorbent is impossible, and the steel by-product gas can pass. In addition, the hollow fiber separation membrane may be in contact with the absorbent.

Further, among the by-produced byproduct gases fed into the hollow fiber separation membrane 101, carbon dioxide has high solubility for the absorbent at high pressure, but hydrogen, nitrogen, etc., which are the remaining gases, are not highly soluble in the absorbent. Therefore, the iron byproduct gas passing through the hollow fiber separation membrane separates carbon dioxide from the absorbent at the interface between the hollow fiber separation membrane and the absorbent, and the remaining undissolved gas is discharged.

The hydrogen recovery apparatus may further include:

A gas pressure controller for controlling the pressure of the steel by-product gas in the absorption module; And

And an absorbent pressure controller for controlling the pressure of the absorbent in the absorption module.

However, since the solubility is not so high under normal atmospheric pressure, the pressures of the steel by-product gas and the absorbent in the absorption module are controlled through the absorber pressure control unit and the gas pressure control unit. As described above, even if the pressure in the absorption module is increased, other gases in the by-product gas other than carbon dioxide are not dissolved in the absorbent, so that carbon dioxide can be effectively separated from the steel by-product gas.

Further, the hydrogen-

A deaeration module 300 connected to the absorption module and through which the absorbent passes; And a first decompression pump (400) for regulating the pressure inside the deaeration module,

The deaeration module includes:

housing; A hollow fiber separator (301) mounted in the housing and supplied with the separated carbon dioxide to the outside of the hollow fiber; An absorber filling space (302) defined by the outside of the hollow fiber membrane and the inside of the housing which constitute the hollow fiber membrane; And a carbon dioxide degassing space 303 inside the hollow fiber separator constituting the hollow fiber separation membrane.

The deaeration module 300 may use a hollow fiber membrane similar to the absorption module 100. Since the absorbent is circulated and supplied as described above, it is the same as the absorbent of the absorption module. However, since the absorbent having passed through the absorption module has a large amount of carbon dioxide dissolved therein, it is possible to degas the carbon dioxide dissolved in the absorbent in the degassing module.

Specifically, the absorbent supplied to the outside of the hollow fiber separator 301 of the deaeration module is in contact with the gas existing in the hollow fiber separator and the carbon dioxide deaerating space 303 in the hollow fiber membrane, and the carbon dioxide dissolved in the absorbent absorbs carbon dioxide To be separated from the absorbent on which degassing has been performed.

The hydrogen recovery apparatus may further include:

An absorbent degassing tank 500 connected to the absorption module 100 and the degassing module 300; And a second decompression pump 600 for regulating the pressure inside the absorbent degassing tank.

The absorbent degassing tank 500 stores the absorbent circulating through the absorption module 100 and the degassing module 300. At this time, the pressure can be reduced to 0.5 atm to 0.9 atm through the second decompression pump for controlling the pressure in the absorbent degassing tank. At this time, the carbon dioxide dissolved in the absorbent may be partially separated, Carbon dioxide can be transferred into the hollow fiber separation membrane 101 of the absorption module.

The hydrogen recovery apparatus may further include:

Is connected to the absorption module may further include a gas separation membrane for purifying hydrogen (H ₂₎ in the gas discharged from the absorption module.

Nitrogen can be separated from the gas containing hydrogen that has passed through the gas absorption membrane through the gas separation membrane to finally purify hydrogen. At this time, the gas separation membrane used for the nitrogen separation can be a well-known one developed by a person skilled in the art.

The hollow fiber membranes of the absorption module and the degassing module may be formed of a material selected from the group consisting of polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polypropylene (PP), perfluoroalkoxy alkanes ), Fluorinated ethylene propylene, ethylene tetrafluoroethylene (ETFE), ethylene fluorinated ethylene propylene (EFEP), polyphenylene, etc. However, And it is not limited to the material which can prevent the diffusion of the absorbent and can form a hollow-type separator having micropores.

The average pore size of the hollow fiber separation membrane of the absorption module and the degassing module may be between 0.001 and 2 micrometers and may be between 0.001 and 1 micrometer but the gas-liquid contact through the hollow fiber separation membrane of the absorption module and the degassing module Pore sizes that can be effectively achieved are not limited thereto.

The porosity of the hollow fiber separator of the absorption module and the degassing module may be between 10% and 90% and may be between 20% and 80%, but the gas-liquid contact through the hollow fiber separator of the absorption module and the degassing module is effective The porosity is not limited thereto.

Water, polypropylene carbonate (PC), polyethylene glycol dimethyl ether (PEGDME) and the like can be used as the absorbent for the absorption module and the degassing module. Preferably, water can be used. However, It is not limited thereto.

At least one of the absorption modules or the deaeration modules may be connected in series or in parallel or in series and parallel.

Hereinafter, the present invention will be described in detail with reference to the following examples and experimental examples.

However, the following examples and experimental examples are illustrative of the present invention, and the scope of the invention is not limited by the examples.

< Example  1> Steel From by-product gas  Hydrogen recovery and carbon dioxide capture

As shown in FIG. 2, the carbon dioxide capture and hydrogen recovery device was constructed from the steel by-product gas, wherein the average pore size of the hollow fiber membrane of the absorption module 100 was 0.2 μm, the effective membrane area was 0.2 m ² , Polypropylene was used. In addition, two absorption modules were connected in series. Steel-product gas was used as a gas having a composition of _{H 2 (20.6%), N} 2 (44.4%), CO 2 (35%) performing a water gas shift conversion (WGS).

Step 1: Water was fed into the absorbent filling space at a flow rate of 500 ml / min using water as the absorbent.

Step 2: The steel by-product gas was supplied into the hollow fiber membrane of the absorption module at a flow rate of 200 ml / min.

Step 3: The absorbent in the absorption module was maintained at a pressure of 3 atm and the iron byproduct gas maintained a pressure of 2.5 atm.

Step 4: The gas containing hydrogen, which is a steel by-product gas passed through the absorption module, and the absorbent in which carbon dioxide is dissolved are separated and discharged.

Water as the absorbent was continuously supplied from an external device.

< Example  2> Steel From by-product gas  Hydrogen recovery and carbon dioxide capture

As shown in FIG. 4, the carbon dioxide capture and hydrogen recovery device was constructed from the steel by-product gas, wherein the average pore size of the hollow fiber membrane of the absorption module 100 was 0.2 μm, the effective membrane area was 0.2 m ² , Polypropylene was used. In addition, two absorption modules were connected in series. Steel-product gas was used as a gas having a composition of _{H 2 (20.6%), N} 2 (44.4%), CO 2 (35%) performing a water gas shift conversion (WGS).

Step 1: Water was fed into the absorbent filling space at a flow rate of 500 ml / min using water as the absorbent.

Step 2: The steel by-product gas was supplied into the hollow fiber membrane of the absorption module at a flow rate of 200 ml / min.

Step 3: The absorbent in the absorption module was maintained at a pressure of 3 atm and the iron byproduct gas maintained a pressure of 2.5 atm.

Step 4: The gas containing hydrogen, which is a steel by-product gas passed through the absorption module, and the absorbent in which carbon dioxide is dissolved are separated and discharged.

At this time, a degassing module 300 for separating the gas containing hydrogen, which is a by-product gas of steel, passed through the absorption module 100 and the absorbent having dissolved carbon dioxide, separates the carbon dioxide dissolved in the absorbent, and the absorbent degassing tank 500 ) Was further constructed, and a step of degassing the carbon dioxide was added.

At this time, the average pore size of the hollow fiber separation membrane 301 of the deaeration module 300 was 0.2 μm, the effective membrane area was 0.2 m ² , and polypropylene was used as the material. In addition, two deaeration modules are connected in series.

The carbon dioxide-dissolved absorbent having undergone Step 4 was supplied to the absorbent degassing tank 500, and the partially dissolved carbon dioxide was degassed by reducing the pressure to 0.8 atm.

Step a: The absorbent supplied from the absorbent degassing tank is supplied to the absorbent filling space 302 of the degassing module 300.

Step b: The internal gas of the hollow fiber separation membrane 301 of the degassing module 300 is discharged to the outside.

Step c: The gas inside the hollow fiber membrane was decompressed to 0.02 atm using the first decompression pump 400 so that the carbon dioxide dissolved in the absorbent in the step a was deaerated into the hollow fiber separation membrane 301.

Step d: The carbon dioxide degassed absorbent and the degassed carbon dioxide were separated and discharged from the hollow fiber separation membrane 301 of the degassing module 300.

< Experimental Example  1> Analysis of hydrogen recovery rate and carbon dioxide removal rate

In order to confirm the hydrogen recovery and the carbon dioxide removal ability of the carbon dioxide capture and hydrogen recovery apparatus from the iron byproduct gas according to the present invention, the gas containing hydrogen separated in the above Example 1 and Example 2 was analyzed by a gas chromatography (Gas Chromatography) The results are shown in FIG.

As shown in FIG. 5, Example 1 comprising a carbon dioxide capture and hydrogen recovery device from a steel by-product gas according to the present invention showed a hydrogen recovery rate of about 90% and a carbon dioxide removal rate, Recovery rate and carbon dioxide removal rate. Therefore, it was confirmed that the degassing module 300 and the absorbent degassing tank 500 were further provided, and the step of degassing the carbon dioxide dissolved in the absorbent had a higher hydrogen recovery rate and a higher carbon dioxide removal rate than the second embodiment.

100: absorption module 101: hollow fiber membrane of absorption module
102: Absorbent filling space of the absorption module
200: absorbent supply part
300: Deaeration module 301: Hollow fiber membrane of deaeration module
302: Absorbent filling space of the degassing module
303: Carbon dioxide degassing space 400: First decompression pump
500: Absorbent degassing tank 600: Second decompression pump
700: gas supply part

Claims (16)

housing; A hollow separator mounted in the housing; And an absorbent filling space defined by an outer side of the hollow fiber membrane constituting the hollow fiber membrane and an inner side of the housing (step 1);
Injecting a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane (step 2);
Adjusting the pressure in the absorption module so that carbon dioxide in the iron byproduct gas can be selectively dissolved in the absorbent (step 3); And
(Step 4) separately separating the absorbent into which the carbon dioxide in the absorbent filling space and the hydrogen-containing gas in the hollow fiber are separated from the absorption module (step 4).
The method according to claim 1,
Wherein the iron byproduct gas in step 2 comprises 0.1 vol% to 80 vol% hydrogen and 0.1 vol% to 80 vol% carbon dioxide.
The method according to claim 1,
The by-product in-process by-product gas in step 2 is a by-product by-product gas that has been subjected to a water-gas shift (WGS) process or a process in which a water gas is not converted. From 15 vol% to 50 vol% hydrogen and from 20 vol% to 50 vol% carbon dioxide.
The method according to claim 1,
(Step 5) of removing carbon dioxide from the absorbent in which the carbon dioxide is dissolved in step 4, and recovering the carbon dioxide from the iron byproduct gas.
The method according to claim 1,
Wherein the steel byproduct gas and the absorbent have a flow rate ratio (steel by-product gas flow rate / absorbent flow rate) of 0.01 to 1.
The method according to claim 1,
Further comprising the step of purifying hydrogen (H ₂ ) using the gas containing hydrogen separated in step 4 by using a gas separation membrane (step 6).
The method according to claim 1,
Wherein the pressure in the absorption module in step 3 is regulated between 0.1 atm and 15 atm. &Lt; RTI ID = 0.0 &gt; 15. &lt; / RTI &gt;
housing; A hollow separator mounted in the housing; And an absorbent filling space defined by the outside of the hollow fiber membrane and the inside of the housing which constitute the hollow fiber membrane.
An absorbent supply part for supplying the absorbent into the absorbent filling space of the absorption module;
A gas supply part for supplying a steel by-product gas containing hydrogen (H ₂ ) and carbon dioxide (CO ₂ ) into the hollow fiber of the hollow fiber separation membrane of the absorption module; And
And an outlet for discharging only the gas containing hydrogen which is not dissolved by the absorbent to the outside of the absorption module.
9. The method of claim 8,
The hydrogen-
A gas pressure controller for controlling the pressure of the steel by-product gas in the absorption module; And
And an absorber pressure controller for controlling the pressure of the absorbent in the absorber module.
9. The method of claim 8,
The hydrogen-
A deaeration module connected to the absorption module and through which the absorbent passes; And
And a first decompression pump for regulating a pressure inside the deaeration module,
The deaeration module includes:
housing; A hollow fiber separator mounted in the housing to inject the separated carbon dioxide into the hollow fiber; An absorbent filling space defined by the outside of the hollow fiber membrane and the inside of the housing which constitute the hollow fiber membrane; And a carbon dioxide deaerating space inside the hollow fiber separator constituting the hollow fiber separator.
9. The method of claim 8,
The hydrogen-
The module is connected to the absorption and carbon dioxide by-product gas from a steel, characterized in that further comprising a gas separation membrane for purifying hydrogen (H ₂₎ in the gas discharged from the absorption module and collecting the hydrogen recovery unit.
11. The method of claim 10,
The hydrogen-
An absorbent degassing tank connected to the absorption module and the degassing module; And
And a second decompression pump for regulating the pressure inside the absorbent degassing tank. &Lt; RTI ID = 0.0 &gt; 8. &lt; / RTI &gt;
11. The method according to claim 8 or 10,
The hollow fiber separation membrane may be formed of a material selected from the group consisting of polytetrafluoroethylene (PTFE), polychlorotrifluoroethylene (PCTFE), polyvinylidene fluoride (PVDF), polypropylene (PP), perfluoroalkoxy alkanes, Characterized in that it is one selected from the group consisting of fluorinated ethylene propylene, ethylene tetrafluoroethylene (ETFE), ethylene fluorinated ethylene propylene (EFEP) and polyphenylene. And a hydrogen recovery device.
11. The method according to claim 8 or 10,
Wherein the hollow fiber separation membrane has an average pore size of 0.001 m to 1 m and a porosity of 10% to 90%.
11. The method according to claim 8 or 10,
Wherein the absorbent is at least one selected from the group consisting of water, polypropylene carbonate (PC), and polyethylene glycol dimethyl ether (PEGDME).
11. The method according to claim 8 or 10,
Wherein at least one of the absorption module or the deaeration module is connected in series or in parallel or in series and parallel combination.

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