KR20210086015A - A production method and system of blue hydrogen - Google Patents

Abstract

The present invention relates to a process and system for producing blue hydrogen, which provides significantly improved reforming efficiency of a feed gas without discharging carbon dioxide to the air during the production of hydrogen through the reforming of a hydrocarbon. Particularly, the system for producing blue hydrogen includes: a raw material supplying unit configured to supply a feed gas including at least a hydrocarbon and steam; a feed gas pretreatment unit; a heat recovery system (HRS) configured to recover the reaction heat and combustion heat in a reforming gas; a reformer configured to receive the preheated feed gas to carry out steam reforming of the hydrocarbon contained in the feed gas; a water gas shift unit configured to carry out water gas shift reaction of carbon monoxide contained in the reforming gas, after receiving the reaction heat discharged from the reformer; a pressure swing adsorption (PSA) unit configured to separate hydrogen from the product discharged from the water gas shift unit; and a hydrogen distribution unit disposed at the rear end of the PSA unit to store the hydrogen or to supply the hydrogen to a specific demand. The system includes a combustion unit configured to carry out combustion of fuel including at least a hydrocarbon to supply heat to the HRS and the reformer, and CO_2 in the combustion gas and CO_2 in the syngas are not discharged to the air but are stored separately.

Description

A production method and system of blue hydrogen

The present invention relates to a blue hydrogen production process and system that recovers carbon dioxide without discharging it into the atmosphere and improves the reforming efficiency of raw material gas.

Hydrogen is an important chemical used in energy, oil refining, fine chemical and petrochemical processes. Typically, it is used in many refinery processes. Recently, as the fossil fuel-based economy is shifting to a hydrogen economy society, the process development of reformers for small fuel cells, hydrogen stations for fuel cell vehicles, and chemical plants for producing large-capacity hydrogen is attracting attention.

Korean Patent Application Laid-Open No. 10-2014-0173366 (Patent Document 1) relates to a method for producing hydrogen using hydrogen PSA off-gas of coke oven gas, and specifically, off-gas remaining after recovering hydrogen from coke oven gas (COG). -Gas), a steam reforming reaction step, a water gas shift reaction step, and a hydrogen pressure swing adsorption (PSA) process step, including a hydrogen pressure swing adsorption (PSA) process step, a method for producing hydrogen using hydrogen PSA off-gas of coke oven gas was presented.

Republic of Korea Patent Publication No. 10-1300331 (Patent Document 2) relates to a hydrogen generator by steam reforming using hydrocarbon as a raw material and a method for operating the same, and more particularly, the moisture introduced into the hydrogen generator by steam reforming is steam A hydrogen generating device by steam reforming that can be supplied as a single phase of , can be operated stably, and high thermal efficiency of the device can be achieved by an appropriate heat exchange method, and an operating method thereof are presented.

Japanese Patent Application Publication No. P4850696 (Patent Document 3) provides a method for generating high-pressure hydrogen with improved thermal efficiency. First, a pressure swing reformer produces a first pressure syngas stream. This synthesis gas is then fed to a hot water gas conversion process to produce a hydrogen-enriched stream from which high pressure hydrogen is obtained. A specific embodiment of the present invention is a process of operating a reformer at a pressure lower than synthesis gas generation, a process of sufficient conditions to supply synthesis gas at a temperature in the range used for the synthesis gas generation process as a water gas conversion reaction, and PSA using a process and PSA. A process for separating hydrogen was presented.

In Korean Patent Publication No. 10-2015-0127890 (Patent Document 4), a hydrogen production apparatus according to an embodiment includes a compressor for compressing a raw material gas at a high pressure; and a reformer equipped with a plurality of heating units for supplying thermal energy to the source gas via a desulfurizer for adsorbing sulfur contained in the high-pressure source gas compressed by the compressor.

The efficiency of the above steam reforming method (the heat of combustion of the generated synthesis gas divided by the heat of combustion of the reforming feedstock and the furnace fuel) is about 74%, but the space velocity is 1000 hr ^-1 . That is, in order to increase the efficiency of the steam reformer of methane, a reformer having a very large capacity must be used, thereby greatly limiting the economic usefulness of the process. Therefore, there is a need to increase the efficiency of steam reforming of methane without increasing the capacity of the reformer.

Greenhouse gas is also generated from natural gas hydrogen stations. When the steam reforming reaction of methane is expressed as a chemical formula, it is shown in Reaction Formula (1).

CH ₄ +H ₂ O → H ₂ +CO ₂ -------------(1)

Instead of extracting hydrogen from methane, carbon dioxide (CO ₂ ) is produced as a by-product. Currently, carbon dioxide from reformers is discharged into the air. This is because not only has the technology to separately collect it in the on-site hydrogen station not yet been prepared, but even if it does, it is not easy to prepare a space to store carbon dioxide even if the reformer has too large capacity.

Republic of Korea Patent Publication No. 10-2014-0173366 Republic of Korea Patent Publication No. 10-1300331 Japanese Patent Publication No. 4850696 Republic of Korea Patent Publication No. 10-2015-0127890

An object of the present invention is to provide a blue hydrogen production process and system in which carbon dioxide is recovered and the reforming efficiency of raw material gas is significantly improved.

The object of the present invention is not limited to the object mentioned above. The objects of the present invention will become more apparent from the following description, and will be realized by means and combinations thereof described in the claims.

Blue hydrogen production process and system according to an embodiment of the present invention is a raw material supply unit for supplying a raw material gas containing at least hydrocarbons and water vapor; pre-processing unit of raw material gas; a reformer that receives the preheated raw material gas and causes a steam reforming reaction of hydrocarbons included in the raw material gas; a heat recovery system (HRS) for recovering and utilizing the heat source for the reforming reaction; a water gas conversion unit that recovers heat in the reformed gas discharged from the reformer and then causes a water gas shift reaction of carbon monoxide contained in the reformed gas; PSA (Pressure Swing Adsorption, PSA) unit for separating hydrogen from the product discharged from the water gas conversion unit; and a hydrogen distribution unit located at the rear end of the PSA unit for compressing and storing the hydrogen or supplying it to a specific demand; and a combustion unit for providing heat to the heat regeneration system and the reformer by burning fuel containing at least hydrocarbons. characterized in that it comprises, and the number of times without releasing to the atmosphere of CO ₂ in the CO ₂ and the synthesis gas in the combustion gas.

The blue hydrogen production process and system according to the present invention recovers carbon dioxide from the hydrocarbon steam reforming system and operates a heat regeneration system to significantly improve the reforming efficiency of the raw material gas, thereby economical and environmental usefulness of the on-site hydrogen station process It is a blue hydrogen manufacturing technology that can significantly increase the energy consumption, and it is judged to be an alternative to green hydrogen based on renewable energy.

The effects of the present invention are not limited to the above-mentioned effects. It should be understood that the effects of the present invention include all effects that can be inferred from the following description.

1 schematically shows a blue hydrogen production system for the production of blue hydrogen according to the present invention.

The above objects, other objects, features and advantages of the present invention will be easily understood through the following preferred embodiments in conjunction with the accompanying drawings. However, the present invention is not limited to the embodiments described herein and may be embodied in other forms. Rather, the embodiments introduced herein are provided so that the disclosed content may be thorough and complete, and the spirit of the present invention may be sufficiently conveyed to those skilled in the art.

In describing each figure, like reference numerals have been used for like elements. In the accompanying drawings, the dimensions of the structures are enlarged than the actual size for clarity of the present invention. Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. The singular expression includes the plural expression unless the context clearly dictates otherwise.

In the present specification, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It is to be understood that it does not preclude the possibility of the presence or addition of numbers, steps, operations, components, parts, or combinations thereof. Also, when a part of a layer, film, region, plate, etc. is said to be “on” another part, this includes not only cases where it is “directly on” another part, but also cases where another part is in between. Conversely, when a part, such as a layer, film, region, plate, etc., is "under" another part, this includes not only cases where it is "under" another part, but also cases where another part is in the middle.

Unless otherwise specified, all numbers, values, and/or expressions expressing quantities of ingredients, reaction conditions, compositions, and combinations used herein are, among other things, the measurements such numbers essentially result in obtaining such values. Since they are approximations reflecting various uncertainties, it should be understood as being modified by the term "about" in all cases. Also, when numerical ranges are disclosed in the present description, such ranges are continuous and inclusive of all values from the minimum to the maximum inclusive of the range, unless otherwise indicated. Furthermore, when such ranges refer to integers, all integers inclusive from the minimum to the maximum inclusive are included, unless otherwise indicated.

1 schematically shows a blue hydrogen production system according to the present invention. Referring to this, the blue hydrogen production system includes: a raw material supply unit for supplying a raw material gas containing at least hydrocarbons and water vapor; pre-processing unit of raw material gas; a reformer (Reformer, 50) that receives the preheated raw material gas and causes a steam reforming reaction of hydrocarbons included in the raw material gas; a heat recovery system that recovers and utilizes the heat source for the reforming reaction (Heat Recovery System, HRS, 40); a water gas conversion unit 60 that receives the reformed gas discharged from the reformer 50, recovers heat in the reformed gas, and then causes a water gas shift reaction (WGS) of carbon monoxide; PSA (Pressure Swing Adsorption, 80) unit for separating hydrogen from the product discharged from the water gas conversion unit 60; and a hydrogen distribution unit 100 positioned at the rear end of the PSA unit 80 to compress and store the hydrogen or supply it to a specific demand. In particular, the hydrogen production apparatus is characterized in that it includes a combustion unit 110 for providing heat to the heat regeneration system 40 and the reformer 50 by burning fuel containing at least hydrocarbons.

Hereinafter, each configuration of the blue hydrogen production system will be described in detail.

The raw material supply unit includes a hydrocarbon supply unit 10 for providing hydrocarbons containing at least methane; a water vapor supply unit 20 providing water and/or water vapor; and a mixing unit 30 for supplying the raw material gas obtained by mixing the hydrocarbon of the hydrocarbon supply unit 10 and the water vapor of the steam supply unit 20 to the heat regeneration system 40 .

The hydrocarbon may include gaseous or liquid hydrocarbons such as natural gas, liquefied natural gas (LNG), liquefied petroleum gas (LPG), naphtha, gasoline, diesel, etc. can However, alcohols such as methanol and ethanol or glycerol may be used according to the purpose or necessity. When the hydrocarbon is liquid, it can be used after being made into a gaseous state through a vaporizer.

The hydrocarbon supply unit 10 includes a hydrocarbon supply line 11 for supplying the hydrocarbon to the mixing unit 30 .

At least one of a pressure control unit 12 , a desulfurization unit 13 , and a pre-reformer 14 may be installed in the hydrocarbon supply line 11 . At this time, the hydrocarbon supply line 11 has the front and rear ends of each configuration so that the hydrocarbons can be selectively introduced into at least one of the pressure control unit 12 , the desulfurization unit 13 and the pre-reformer 14 . The bypass pipe (12a, 13a, 14a) may be provided. According to the present invention, hydrocarbons can be selectively passed through the pressure control unit 12, the desulfurization unit 13, and the pre-reformer 14 according to the type, state, etc., so there is no need to perform an unnecessary process. Accordingly, the economic usefulness of the process can be improved.

The water vapor supply unit 20 includes a water vapor supply line 21 for supplying moisture and/or water vapor to the mixing unit 30 .

A steam generator 22 is installed in the steam supply line 21 to convert liquid moisture into steam. However, when the amount of moisture is small or absent, bypass pipes may be provided at the front and rear ends of the steam generator 22 so that the raw material can bypass the steam generator 22 .

The mixing unit 30 supplies the raw material gas including the hydrocarbon and water vapor to the heat regeneration system 40 . In this case, the molar ratio of carbon to water vapor in the source gas (S/C molar ratio) may be 1: 2.5 to 4.0. If the molar ratio of carbon to water vapor is less than 1: 2.5, the reforming catalyst may be poisoned by carbon due to lack of water vapor and thus performance may be deteriorated, and if it exceeds 1: 4, there is a problem in that thermal efficiency is lowered due to excessive injection of water vapor. .

The unreacted water vapor separated from the first separation unit 70 to be described later may be introduced into the mixing unit 30 and mixed with the raw material gas. By separating the unreacted steam remaining after the steam reforming reaction of the source gas (to be precise, the hydrocarbon) and the water gas conversion reaction of the reformed gas and supplying it to the source gas again, the hydrogen production efficiency according to the present invention can be greatly improved. .

The raw material gas is introduced into the heat regeneration system 40 to be preheated, and then supplied to the reformer 50 to undergo a steam reforming reaction. The present invention is characterized in that the heat required for the preheating of the raw material gas and the steam reforming reaction of hydrocarbons is supplied through the combustion unit 110 .

Specifically, the combustion unit 110 generates heat by burning fuel supplied from the outside and unreacted hydrocarbons separated from the second separation unit 90 to be described later. The heat is supplied to the reformer 50 to cause a steam reforming reaction of hydrocarbons, and is supplied to the heat regeneration system 40 to preheat the raw material gas.

By preheating the raw material gas with the heat regeneration system 40, not only can the raw material gas be heated to a temperature suitable for the steam reforming reaction, but also a single phase in which the water vapor contained in the raw material gas is vaporized without phase separation be able to keep it Therefore, the efficiency of the steam reforming reaction of hydrocarbons can be further improved.

The reformer 50 is configured to cause a steam reforming reaction of hydrocarbons as described below by receiving the preheated raw material gas. The reformed gas discharged from the reformer 50 may include at least hydrogen (H ₂ ), carbon monoxide (CO), carbon dioxide (CO ₂ ), methane (CH ₄ ), and water vapor (H ₂ O).

C _m H _n + mH ₂ O → mCO + (m+n/2)H ₂ --- (2)

CO + 3H ₂ ↔ CH ₄ + H ₂ O --- (3)

CO + H ₂ O ↔ CO ₂ + H ₂ --- (4)

The reformer 50 contacts the raw material gas on the reforming catalyst and causes a steam reforming reaction to produce synthesis gas, which is a gas containing high concentration of hydrogen. The reforming catalyst may include a catalyst in which a metal such as nickel or ruthenium is supported on a carrier such as alumina, silica, and magnesium aluminate.

In order to increase the hydrogen production rate of the steam reforming reaction of the hydrocarbon, it may be preferable to maintain the temperature of the reformer 50 at 600° C. to 900° C. The temperature of the reformer 50 may be adjusted by the heat and combustion gas discharged from the above-described combustion unit 110 . The combustion gas discharged from the combustion unit 110 passes through the reformer 50 and the heat regeneration system 40 and flows into the water gas conversion unit 60 to be described later, and the temperature of the reformer 50 is adjusted as above. In this case, when the combustion gas passes through the reformer 50, the temperature is 800° C. to 850° C., and when it passes through the heat regeneration system 40, the temperature is cooled to about 200° C. to 400° C. or less. can

The heat regeneration system 40 and the reformer 50 may be a reactor of an integrated structure, and the source gas may be introduced into the reformer 50 through the heat regeneration system 40 within the reactor. The heat regeneration system 40 and the reformer 50 may be provided in communication with each other. However, the present invention is not limited thereto, and the heat regeneration system 40 and the reformer 50 may be separate devices physically separated from each other.

The flow of combustion gas discharged from the combustion unit 110 is as follows. The combustion gas is generated by combustion of hydrocarbons _{, and may include at least carbon dioxide (CO 2} ) and water vapor (H ₂ O).

First, the combustion gas may be introduced into the water gas conversion unit 60 through the reformer 40 and the heat regeneration system 50 as described above. After the combustion gas recovers waste heat, carbon dioxide in the combustion gas may be separated from the carbon dioxide recovery unit 150 and then stored in the carbon dioxide storage unit 160 . Meanwhile, water vapor in the combustion gas may be consumed by participating in a water gas conversion reaction of carbon monoxide (CO) included in the reformed gas to be described later.

Next, the combustion gas passes through the reformer 50 and the pre-reformer 14 to supply heat necessary for the development of hydrocarbons. The combustion gas passing through the pre-reformer 14 may be introduced into the combustion unit 110 again.

As described above, according to the present invention, the amount of heat generated by the fuel introduced from the outside is not discharged to the outside, and carbon dioxide, which is the main component of the greenhouse gas, is separated and stored in a buffer tank and then _{moved to the CO 2} treatment place to produce blue hydrogen. , can greatly improve the thermal efficiency of the process.

The reformed gas discharged from the reformer 50 is introduced into the water gas conversion unit 60 . The water gas conversion unit 60 produces hydrogen from the carbon monoxide by causing a water gas conversion reaction of carbon monoxide (CO) contained in the reformed gas as shown in the following formula.

CO + H ₂ O ↔ CO ₂ + H ₂ --- (4)

The water gas conversion unit 60 may be filled with a water gas conversion catalyst for converting carbon monoxide in the reformed gas with water into carbon dioxide and hydrogen. The water gas conversion catalyst is copper-zinc (Cu-Zn-Al ₂ O ₃ A copper-based catalyst which is an oxide such as _{iron-chromium (Fe 2} O ₃ -Cr ₂ O ₃ catalyst) and/or iron-based catalyst) may be preferably used. The reaction temperature is Cu-Zn-Al ₂ O ₃ 200° C. to 250° C. for a catalyst based on Fe ₂ O ₃ -Cr ₂ O _{3 For a} catalyst based on 300° C. to 450° C. are used.

Water vapor in the combustion gas resulting from the combustion unit 110 may participate in the water gas conversion reaction that occurs in the water gas conversion unit 60 as described above.

The water gas conversion unit 60 may separate carbon dioxide from the product of the water gas conversion reaction, and the carbon dioxide may be stored in the first carbon dioxide storage unit 160 through the first carbon dioxide regeneration unit 150 . As described above, the present invention maximizes the conversion efficiency of the raw material gas and maximizes the performance of the thermal efficiency in the process by the heat regeneration system, so that the capacity of the reformer can be greatly reduced unlike the prior art. This means that a space corresponding to the reduced capacity of the reformer is secured, and the space can be used as a carbon dioxide storage unit. That is, another feature of the present invention is the production process and system of blue hydrogen in which carbon dioxide is not emitted to the outside in the overall process as it can be stored without discharging carbon dioxide to the outside.

A first separation unit 70 may be provided at the rear end of the water gas conversion unit 60 . _{The first separation unit 70 may separate unreacted H 2} O from the product of the water gas conversion unit 60 and provide it to the mixing unit 30 of the raw material supply unit as described above. The unreacted H ₂ O is mixed with the raw material gas to participate in the steam reforming reaction of hydrocarbons described above.

The product from which unreacted water vapor is separated by the first separation unit 70 may include hydrogen (H ₂ ), methane (CH ₄ ), and a trace amount of carbon dioxide (CO ₂ ). The product is then supplied to the PSA unit 80 .

The PSA unit 80 is configured to purify hydrogen by adsorbing and removing impure gases other than hydrogen from the high-concentration hydrogen-containing gas using an adsorbent.

The hydrogen separated by the PSA unit 80 is provided to the hydrogen distribution unit 100 through the first buffer tank 120 , the compressor 130 , and the second buffer tank 14 , and the hydrogen distribution unit 100 . ) may be stored in the hydrogen storage tank 190, or may be supplied to an appropriate consumer (200).

Off-Gas of the PSA unit 80 may be supplied to the combustion unit and used as fuel for combustion, or some may be recycled back to the PSA unit 80 to increase the purity of hydrogen gas, and the second separator 90 It can be used to separate unreacted methane and CO _{2 .} The second separator 90 is configured to separate off-gas discharged from the PSA unit 80 into methane (CH ₄ ) and carbon dioxide. The methane is mixed with fuel flowing into the combustion unit 110 and burned, and the carbon dioxide is stored in the carbon dioxide storage unit 160 through the carbon dioxide regeneration unit 150 .

The process of obtaining hydrogen using the blue hydrogen production system is as follows.

First, looking at the flow of the raw material gas, the hydrocarbon and water vapor respectively supplied from the hydrocarbon supply unit 10 and the water vapor supply unit 20 are introduced into the heat regeneration system 40 through the mixing unit 30 . The raw material gas preheated in the heat regeneration system 40 is provided to the reformer 50 . In the reformer 50, the hydrocarbon in the raw material gas is subjected to a steam reforming reaction to produce a synthesis gas containing _{hydrogen (H 2 ) in a high concentration.} The synthesis gas is provided to the water gas conversion unit 60, and the water gas conversion unit 60 adds carbon monoxide remaining in the synthesis gas and carbon monoxide in the combustion gas resulting from the combustion unit 110 through the water gas conversion reaction. Produces hydrogen (H ₂ ). After separating unreacted water vapor and carbon dioxide remaining in the above product, the product is provided to the PSA unit to separate _{hydrogen (H 2 ).} The separated hydrogen is stored through the hydrogen distribution unit 100 or supplied to a specific demand.

The amount of heat required in the above process may be obtained by burning the fuel introduced from the outside through the combustion unit 110 and the methane separated by the second separation unit 90 . The combustion gas discharged from the combustion unit 110 passes through the reformer 50 and the heat regeneration system 40 to recover waste heat, and the CO ₂ rich gas is _{separated by a CO 2} separation process and then is not released to the atmosphere. After storage, it is characterized in that it is processed after being transferred to a _{CO 2 treatment place.}

As the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited to the above-described embodiments, and various modifications and variations by those skilled in the art using the basic concept of the present invention as defined in the following claims The improved form is also included in the scope of the present invention.

10: hydrocarbon supply unit 11: hydrocarbon supply line 12: pressure control unit
13: desulfurization unit 14: pre-reformer 20: steam supply unit
21: steam supply line 22: steam generator 30: mixing unit
40: heat regeneration system 50: reformer 60: water gas conversion unit
70: first separation unit 80: PSA unit 90: second separation unit
100: hydrogen distribution unit 110: combustion unit 120: first buffer tank
130: compressor 140: second buffer tank
150: carbon dioxide regeneration unit 160: carbon dioxide storage unit
170: carbon dioxide storage and conversion system
180: hydrogen storage tank 190: customer

Claims (12)

a raw material supply unit for supplying a raw material gas containing at least hydrocarbons and water vapor;
a pre-processing unit of the raw material gas;
a reformer that receives and preheats the raw material gas and causes a steam reforming reaction of hydrocarbons included in the raw material gas;
a heat recovery system (HRS) for recovering reaction heat and combustion heat in the reformed gas discharged from the reformer;
a water gas conversion unit receiving the reformed gas discharged from the reformer and causing a water gas shift reaction of carbon monoxide contained in the reformed gas;
PSA (Pressure Swing Adsorption, PSA) unit for separating hydrogen from the product discharged from the water gas conversion unit; and
A hydrogen distribution unit located at the rear end of the PSA unit to store the hydrogen or supply it to a specific demand;
and a combustion unit that burns fuel containing at least hydrocarbon to provide heat to the heat regeneration system and the reformer,
Carbon dioxide in the combustion gas (CO ₂₎ and hydrogen gas production apparatus of glass (off-gas) separated without release into the atmosphere of carbon dioxide (CO ₂₎ in the storage and characterized in that it is discharged from the PSA unit. According to claim 1,
The raw material supply unit is a hydrocarbon supply unit; water vapor supply; and a mixing unit for supplying a raw material gas obtained by mixing hydrocarbons of the hydrocarbon supply unit and water vapor of the steam supply unit to the thermal regeneration system. 3. The method of claim 2,
The pre-processing unit includes a pressure control unit for adjusting the pressure according to the type of hydrocarbon; desulfurization unit; And a hydrogen production device comprising at least one of a pre-reformer (Pre-Reformer). 4. The method of claim 3,
The pretreatment unit is hydrogen production apparatus, characterized in that the hydrocarbon is provided with a bypass pipe to selectively introduce at least one of the pressure control unit, the desulfurization unit and the pre-reformer. According to claim 1,
The water vapor of the raw material gas preheated by the heat regeneration system is introduced into the reformer while maintaining a vaporized single phase without phase separation. According to claim 1,
The heat regeneration system and the reformer are reactors of an integrated structure, and the heat regeneration system and the reformer are provided in communication with the reformer in the reactor so that the raw material gas can be introduced into the reformer through the heat regeneration system. hydrogen production device. According to claim 1,
The combustion gas discharged by burning fuel in the combustion unit passes through a reformer and a heat regeneration system and is introduced into the water gas conversion unit. 4. The method of claim 3,
The combustion gas discharged by burning fuel in the combustion unit passes through a reformer and passes through the pre-reformer to provide heat to the pre-reformer. According to claim 1,
Carbon dioxide contained in the combustion gas from which waste heat is recovered in the heat regeneration system is _{separated through a carbon dioxide (CO 2} ) recovery unit, and is stored in a carbon dioxide storage tank and is not discharged into the atmosphere. 3. The method of claim 2,
It is provided at the rear end of the water gas conversion unit to separate the unreacted water vapor from the product of the water gas conversion unit, and hydrogen production apparatus, characterized in that it further comprises a first separation unit for supplying it to the mixing unit. 10. The method of claim 9,
Off-gas discharged from the PSA unit flows into the combustion unit, flows into the reformer, flows back into the PSA unit, or flows into the second separation unit located at the rear end of the PSA unit. hydrogen production device. 12. The method of claim 11,
The second separator separates the residual gas into hydrocarbon and carbon dioxide,
The hydrocarbon is introduced into the combustion unit, and the carbon dioxide is stored in the carbon dioxide storage tank through the carbon dioxide recovery unit.

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