KR102508711B1 - Hydrogen amplification process from by-product gas using a hydrogen separation membrane - Google Patents

Abstract

In the present invention, based on the gas flow direction connected from the module inlet (feed port) to the outlet, the first space ( ^1st room), the second space ( ^2nd room), ... , It relates to a hydrogen amplification process for performing a hydrogen generation reaction from a hydrogen-containing by-product gas in a membrane reactor having a membrane module divided into n ^th rooms (n ≥ 2).
At this time, the first space removes and recovers some or all of the hydrogen from the hydrogen-containing by-product gas through the hydrogen separation membrane, thereby breaking the thermodynamic equilibrium according to LeCharlier's law, and the forward reaction occurs in the second space where the hydrogen generation reaction is performed. It is designed to proceed, and the second space is characterized by being designed to remove and recover some or all of the hydrogen through a hydrogen separation membrane while performing a hydrogen generation reaction from a by-product gas from which hydrogen is partially or completely removed in the first space.
Examples of usable off-gas sources include the steel industry, the petrochemical industry, industries that emit ammonia containing hydrogen, and biogas (sewage treatment plants, landfills, livestock manure, etc.).

Description

Hydrogen amplification process of by-product gas using a hydrogen separation membrane { Hydrogen amplification process from by-product gas using a hydrogen separation membrane }

The present invention is a hydrogen amplification process of by-product gas using a hydrogen separation membrane, specifically, a first space (1 ^st room) and a second space (2 ^nd room) based on the gas flow direction connected from the module inlet (feed port) to the outlet , … , It relates to a hydrogen amplification process for performing a hydrogen generation reaction from a hydrogen-containing by-product gas in a membrane reactor having a membrane module divided into n ^th rooms (n ≥ 2).

Non-limiting examples of usable sources of by-product gas include the steel industry, the petrochemical industry, industries that emit ammonia containing hydrogen, and biogas (such as sewage treatment plants, landfills, livestock manure, and other biomass processing facilities).

Hydrogen has received much attention as a clean energy carrier and is one of the most promising alternative energy sources in the world due to its economical, environmentally friendly and renewable use. Currently, large amounts of hydrogen are produced from fossil fuel-based methods such as natural gas steam reforming, coal gasification, water electrolysis, biomass gasification and other thermochemical processes.

On the other hand, natural gas, coal, and biomass produce syngas through a reforming reaction, and the produced syngas is used for chemical synthesis raw materials, fuels, and industrial processes through various downstream processes. In addition, the produced syngas contains a large amount of hydrogen, which is used in ammonia synthesis, oil refining process, smelting process, polysilicon manufacturing process, semiconductor manufacturing process, and LED manufacturing process through the purification process. It is an essential substance. In particular, when hydrogen is linked with a fuel cell, its value is increasing day by day as a clean energy source with high efficiency and no emission of pollutants.

Hydrogen fuel cells have relatively high energy efficiency compared to other renewable energies such as sunlight, solar heat, and wind power. In addition, while wind power and solar power have many ups and downs in output depending on climatic conditions, in the case of a hydrogen fuel cell, the desired output capacity can be designed in advance according to the purpose, so hydrogen is the most stable energy resource and is the best renewable energy. can be said

In addition, it is expected that the demand for eco-friendly vehicles, including hydrogen fuel cell vehicles, will increase as automotive environmental regulations are strengthened worldwide, and accordingly, the construction of hydrogen filling stations is expected to increase. There are two types of hydrogen filling stations: off-site method, which purifies by-product hydrogen generated in petrochemical complexes, etc., and compresses it to high pressure to transport and store it, and on-site method, which manufactures and supplies hydrogen at the charging station site. The hydrogen production facility of the on-site hydrogen filling station mainly uses the natural gas reforming reaction.

Currently, commercially available hydrogen purification processes include adsorption, membrane separation, and deep cooling. Pressure Swing Adsorption (PSA), Thermal Swing Adsorption (TSA), Cryogenic Distillation, and Getter are commercially available processes, but they have low energy efficiency and require complex configurations.

Hydrogen separation membranes play an important role in hydrogen production and purification. Among various hydrogen permeable membranes, Pd-based membranes are excellent for use in commercial applications such as hydrocarbon steam reforming, fuel cells, and hydrogen-based reactions because of their excellent hydrogen selectivity. In addition, Pd-based membranes can overcome the thermodynamic equilibrium limit predicted by Le Chatelier's principle to improve the product yield of the reaction and enhance the conversion. Thus, by using a Pd-based membrane, the SMR and WGS units can be integrated, and the downstream hydrogen purification unit can be eliminated, thereby improving conversion efficiency while reducing overall reactor volume and process cost.

Depending on the membrane construction, Pd-based membranes can be structurally classified into self-supported and composite membranes. Pd and Pd alloy foils have been commercialized to supply high purity hydrogen (>99.999%) to the semiconductor and electronics industries. However, in order to produce ultra-high purity hydrogen on an industrial scale, the film thickness must be greater than 15 μm to maintain structural integrity. This increases material cost and reduces the hydrogen permeation flux. Compared to foil-type membranes, composite membranes have attracted great interest due to their low cost, excellent hydrogen permeation flux and high mechanical strength. Several studies have reported the fabrication of Pd composite membranes using porous supports that help reduce the membrane thickness while maintaining mechanical strength. Recently, research is being conducted in accordance with the demand for long-term thermal stability and module design.

On the other hand, 50 ~ 5,000 Nm ³ to supply hydrogen to various industrial facilities such as ammonia synthesis, oil refining process, semiconductor manufacturing process, LED manufacturing process, polysilicon manufacturing process, and steel industry, breaking away from the existing transportation supply method. /h Class small and medium-sized hydrogen production plants are actively being developed.

As an example, the types of by-product gases generated in the steel industry and the composition of dry gas after pretreatment of impurities are shown in Table 1 below.

A large amount of by-product gas is generated in the steel industry. Depending on each process, coke oven gas (COG), blast furnace gas (BFG), and converter gas (Lintz-Donawiaz convert Gas, LDG), etc. In the by-product gas of steelmaking, fuel materials such as H ₂ , CH ₄ , CO and CO ₂ and the like and basic raw materials for chemical synthesis are included as main components.

Iron ore and coke are needed to make molten iron, and coke refers to raw coal that is steamed into small lumps before being put into a blast furnace. The gas generated during the dry distillation of bituminous coal in a coke _oven is coke oven gas (COG ⁾ . contains this.

BFG is a gas generated when iron ore and coke are charged into a blast furnace to produce pig iron, and coke is combusted during a reduction reaction with iron ore. It contains a large amount of nitrogen because air is used during the process. The calorific value is 750 Kcal/Nm ³ .

Converter gas (LDG) is a gas generated in the process of converting pig iron into steel. It is a gas generated when carbon in the molten iron is combined with oxygen in the process of charging molten iron into the converter of a steel mill and blowing oxygen. The calorific value is 2,000 Kcal. /Nm is ³ . LDG is a hazardous substance, with carbon monoxide accounting for 50 to 80%, the highest proportion, and composed of hydrogen, nitrogen, carbon dioxide, and carbon monoxide.

On the other hand, natural gas, a representative material among hydrocarbons, has methane as its main component. Steam Methane Reforming (SMR) of methane reforms methane gas in the presence of steam using a catalyst to obtain syngas (CO + H ₂ It is a reaction that chemically converts into a mixed gas).

[Scheme 1]

CH ₄ + H ₂ O → CO + 3H ₂ ΔH = 206.28 kJ/mol

SMR has a CO ₂ /H ₂ ratio in the product gas of 0.25, and has advantages in that the CO ₂ production rate is lower than that of partial oxidation processes using hydrocarbons as raw materials, and that a larger amount of hydrogen can be obtained from a certain amount of hydrocarbons.

Since the CO/H ₂ ratio is high in the fluid produced in the SMR process, CO can be converted into CO ₂ and H ₂ through a conversion reaction as shown in Scheme 2 below. This is called the water-gas shift reaction (WGS).

[Scheme 2]

CO + H ₂ O → CO ₂ + H ₂ ΔH = -41.3 kJ/mol

The conversion reaction includes a high-temperature conversion reaction and a low-temperature conversion reaction depending on the temperature.

Accordingly, a high temperature shift reaction (HTS) process and a low temperature shift reaction (LTS) process may be connected after the SMR process. The high-temperature conversion reaction may be performed at 350 to 550 °C using a Fe ₂ O ₃ catalyst in which Cr ₂ O ₃ is added as a cocatalyst. The chemical components of typical catalysts used are Fe (56.5 to 57.5%) and Cr (5.6 to 6.0%). The low-temperature conversion reaction is performed at 200 to 250° C., and a catalyst such as CuO (15 to 31%)/ZnO (36 to 62%)/Al ₂ O ₃ (0 to 40%) is used. Recently, Cr-based low-temperature conversion catalysts have been developed. The minimum reaction temperature must be higher than the dew point of water gas, and the CO concentration in the exhaust gas is 1% or less. The low-temperature conversion catalyst is initially used after being converted to a reduced state through an activation process.

The present invention focuses on the fact that a large amount of hydrogen-containing by-product gas is discharged in the steel industry, petrochemical industry, ammonia emission industry containing hydrogen, or as biogas (sewage treatment plant, landfill, livestock manure, etc.), and hydrogen-containing by-product gas It is intended to provide an integrated membrane reactor design that can simultaneously perform the hydrogen amplification process and the hydrogen recovery process of.

A first aspect of the present invention is a hydrogen amplification membrane reactor that performs a hydrogen generation reaction while removing and recovering hydrogen from a hydrogen-containing by-product gas through a hydrogen separation membrane,

Based on the gas flow direction connected from the module inlet (feed port) to the outlet, the first space ( ^1st room), the second space ( ^2nd room), ... , having a separation membrane module divided into n ^th room (n ≥ 2),

In the first space, some or all of the hydrogen is removed and recovered from the hydrogen-containing by-product gas through the hydrogen separation membrane, and the forward reaction can proceed in the second space where the hydrogen generation reaction is performed by breaking the thermodynamic equilibrium according to LeCharlier's law. is designed to be

The second space provides a hydrogen amplification membrane reactor, which is designed to remove and recover some or all of the hydrogen through a hydrogen separation membrane while performing a hydrogen generation reaction from a by-product gas from which hydrogen is partially or completely removed in the first space.

The second aspect of the present invention is based on the gas flow direction connected from the module inlet (feed port) to the outlet, the first space (1 ^st room), the second space (2 ^nd room), ... , a hydrogen amplification process of performing a hydrogen generation reaction from a hydrogen-containing by-product gas in a separation membrane reactor equipped with a separation membrane module divided into n ^th room (n ≥ 2),

Removing and recovering some or all of hydrogen from a hydrogen-containing by-product gas through a hydrogen separation membrane in the first space so that the forward reaction can proceed in the second space where the hydrogen production reaction is performed by breaking the thermodynamic equilibrium according to LeCharlier's law Step 1; and

A second step of removing and recovering some or all of the hydrogen through a hydrogen separation membrane while performing a hydrogen generation reaction in the second space from the by-product gas from which hydrogen is partially or entirely removed in the first step.

It provides a method for producing hydrogen through hydrogen amplification of by-product gas, characterized by comprising a.

A third aspect of the present invention is a hydrogen amplification membrane reactor of the first aspect; and a fuel cell using the hydrogen-enriched gas provided from the hydrogen-amplified membrane reactor as fuel.

Hereinafter, the present invention will be described.

The membrane stage cut, defined as the fraction of feed gas that permeates the membrane, is a measure of the degree of separation required. A typical goal of a gas separation system is to produce a residue stream substantially free of permeable components and a concentrated permeate stream.

According to the present invention, a hydrogen amplification membrane reactor that performs a hydrogen generation reaction while removing and recovering hydrogen from a hydrogen-containing by-product gas through a hydrogen separation membrane,

As illustrated in FIG. 1, the first space ( ^1st room), the second space ( ^2nd room), ... based on the gas flow direction connected from the module inlet (feed port) to the outlet. , having a separation membrane module divided into n ^th room (n ≥ 2),

The second space (e.g., zone 2) of the separation membrane module that performs the hydrogen generation reaction through the thermodynamic equilibrium breakthrough according to LeCharlier's law. Preferably, the separation membrane module It is characterized in that some or all of the hydrogen is removed from the hydrogen-containing by-product gas through a hydrogen separation membrane (eg, membrane) in the first space (eg, zone 1).

To this end, the first space of the separation membrane module removes and recovers some or all of hydrogen from the hydrogen-containing by-product gas through a hydrogen separation membrane, and the second space performs a hydrogen generation reaction by breaking the thermodynamic equilibrium according to LeCharlier's law. It is designed so that a direct reaction can proceed in space;

The second space of the separation membrane module may be designed to remove and recover some or all of the hydrogen through the hydrogen separation membrane while performing a hydrogen generation reaction from a by-product gas from which hydrogen is partially or entirely removed in the first space.

In the present invention, the boundary of each space of the separation membrane module may be (i) partitioned by a partition wall and/or (ii) formed depending on whether the hydrogen generation reaction proceeds as a forward reaction in conjunction with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas. there is. In the latter case, the boundary of each space may change with time, and may be a continuous space in association with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas.

In the present invention, each space of the membrane module is (i) whether or not there is a catalyst for hydrogen generation reaction; (ii) whether the hydrogen generation reaction proceeds as a forward reaction in conjunction with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas; (iii) the use of different combinations of catalysts for hydrogen production; (iv) different hydrogen production conditions and/or (v) partition walls, which can be separated from other adjacent spaces.

In the present invention, the hydrogen separation membranes disposed in different spaces of the separation membrane module may be the same or different, and/or the hydrogen separation membranes disposed in the same space of the separation membrane module may be the same or different. For example, the same space of the separation membrane module may have the same hydrogen partial pressure gradient pattern in the hydrogen-containing mixed gas based on the gas flow direction.

In the present invention, the second space of the separation membrane module is whether or not there is a catalyst for generating hydrogen (Figs. 1 and 4); Whether or not the hydrogen generation reaction proceeds as a forward reaction in conjunction with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas (FIG. 6); Use of different catalysts for hydrogen production (FIG. 5); And/or partition walls (Figs. 4 to 6) may also distinguish it from the first space.

Through the bulkhead (blue), the first space (1 ^st room), the second space (2 ^nd room), … , in the separation membrane module divided into n ^th room (n ≥ 2),

(i) In the first space, some or all of hydrogen is removed and recovered from the hydrogen-containing by-product gas through a hydrogen separation membrane, and the thermodynamic equilibrium according to LeCharlier's law is broken, and the hydrogen generation reaction is performed in the second space. (ii) the second space is designed to remove and recover some or all of the hydrogen through a hydrogen separation membrane while performing a hydrogen generation reaction from the by-product gas from which hydrogen is partially or completely removed in the first space A feature of the present invention is

Two consecutive spaces, that is, the second space and the third space, the third space and the fourth space, ... , the case where it is applied to at least one of the n-1th space and the nth space belongs to the scope of the present invention, as well as the case where it is applied within one space partitioned through a partition wall (blue) also belongs to the scope of the present invention. .

Non-limiting examples of hydrogen production reactions that can be used in the present invention include steam reforming (SR), partial oxidation (POx), autothermal reforming (ATR), water gas shift reaction ( There are reversible reactions such as water gas shift (WGS) and ammonia decomposition.

(1) Steam reforming (SR):

C _n H _m + nH ₂ O ↔ nCO + (n+1/2m)H ₂

(2) Partial oxidation (POx):

C _n H _m + 1/2O ₂ ↔ nCO + 1/2 mH ₂

(3) Autothermal reforming (ATR):

C _n H _m + 1/2nH ₂ O + 1/4nO ₂ ↔ nCO + (1/2n+1/2m)H ₂

(4) Water gas shift (WGS):

CO + H ₂ O ↔ CO ₂ + H ₂

(5) Ammonia decomposition:

2NH ₃ ↔ N ₂ + 3H ₂

[ Shell-and-Tube Type Membrane Module ]

As illustrated in FIG. 3A, the separation membrane module of the present invention may be a shell-and-tube module having tubular hydrogen separation membranes. One or two or more tubular hydrogen separation membranes may be disposed in each space, and as illustrated in FIG. 1, each space may be divided in the longitudinal direction of one tubular hydrogen separation membrane. Furthermore, as illustrated in FIG. 3A, one or more barrier ribs (blue) may be concentrically disposed inside the shell-and-tube module, and a tubular hydrogen separation membrane may be installed in a space separated through the barrier rib.

The hydrogen amplification membrane reactor of the present invention is equipped with a shell-and-tube type membrane module using a tubular hydrogen separation membrane, and as illustrated in FIGS. 1 and 4 to 6, a catalyst for hydrogen generation reaction is installed in the required space. (eg, filling and/or coating) may be used.

In the present invention, these features can be implemented in one module as shown in FIG. From an economical point of view, n is preferably 7 or less, more preferably 4 or less.

In the present invention, the tubular hydrogen separation membrane also belongs to the category of the cylindrical hydrogen separation membrane. In the cylindrical hydrogen separation membrane, for example, a metal dense membrane for hydrogen separation is disposed outside the cylindrical porous support, and hydrogen-enriched gas can be collected in the pores of the cylindrical porous support.

As illustrated in FIGS. 3 to 6, the present invention is a shell-and-tube type membrane module having a tubular hydrogen separation membrane (FIG. 3) or a hydrogen amplification membrane reactor (FIGS. 4 to 6) when hydrogen separation proceeds. In order to increase the recovery rate,

Based on the gas flow direction connected from the module inlet (feed port) to the outlet, the first space (1 ^st room), the second space (2 ^nd room), ... , divide the n ^th room (n ≥ 2),

In each space, based on a tubular hydrogen separation membrane that passes hydrogen from the first surface, which is outside, to the second surface, which is inside, hydrogen partial pressure on the first surface side (P _outside ) > hydrogen partial pressure on the second surface side ( P _inside ) and the separation membrane module can be designed so that one or more tubular hydrogen separation membranes are disposed to discharge hydrogen passing through the hydrogen separation membrane through an open part on the second side.

In order for hydrogen to permeate the membrane, there must be a difference in hydrogen partial pressure across the membrane. That is, in order to pass hydrogen from the first surface, which is outside, to the second surface, which is inside, in the tubular hydrogen separation membrane, the hydrogen partial pressure on the first surface side (P _outside ) > the hydrogen partial pressure on the second surface side (P _inside ) should be

Where, P _i : Hydrogen partial pressure,

P _inside : internal hydrogen partial pressure of the tubular hydrogen separation membrane,

P _outside : External hydrogen partial pressure of the tubular hydrogen separation membrane.

As hydrogen passes from the outside to the inside of the tubular hydrogen separation membrane, the partial pressure difference between the hydrogen partial pressure on the supply side (P _outside ) and the hydrogen partial pressure on the permeation side (P _inside ) decreases as it goes downstream in the longitudinal direction of the tubular hydrogen separation membrane. The amount of hydrogen recovered may decrease and eventually become zero.

As shown in FIGS. 1 and 3, in the shell-and-tube type separation membrane module having the first stage tubular hydrogen separation membrane module, the hydrogen separation reaction does not occur in Zone 1 where the hydrogen partial pressure relationship is P ₁ > P ₂ in the first stage module. However, since there is no difference in hydrogen partial pressure after Zone 2 where P ₂ ≒ P ₃ , it does not act as a separator.

Therefore, the present invention is to increase the hydrogen recovery rate in a shell-and-tubular membrane module equipped with a tubular hydrogen separation membrane, that is, hydrogen partial pressure so that hydrogen can permeate and recover hydrogen even in Zone 2 of the first-stage tubular hydrogen separation membrane module. In order to give a difference, (i) a two-stage tubular type that divides the tubular hydrogen separation membrane into Zone 1 and Zone 2 and configures the tubular hydrogen separation membrane in each zone separately, but does not connect in series in terms of the hydrogen flow through the hydrogen separation membrane. designing a hydrogen separation membrane module; And / or (ii) it is characterized by performing a hydrogen generation reaction in Zone 2.

As illustrated in FIG. 3A, in the two-stage tubular hydrogen separation membrane module, in the first-stage tubular hydrogen separation membrane module, the hydrogen partial pressure relationship is P ₁ > P ₂ downstream of Zone 1 until P ₂ ≒ P ₃ . When the separation proceeds and the remaining hydrogen becomes P ₅ ≒ P ₆ in Zone 2 where the hydrogen partial pressure relationship is P ₄ > P ₅ in the second-stage tubular hydrogen separation membrane module designed to have a partial pressure difference capable of permeating hydrogen By the secondary hydrogen separation up to , the hydrogen recovery rate that can be implemented in the first-stage tubular hydrogen separation membrane module is added to the hydrogen recovery rate that can be implemented in the second-stage tubular hydrogen separation membrane module, thereby increasing the overall hydrogen recovery rate of the separation membrane module.

That is, the present invention provides a first space ( ^1st room), a second space ( ^2nd room), ... , divide the n ^th room (n ≥ 2),

In each space, based on a tubular hydrogen separation membrane that passes hydrogen from the first surface, which is outside, to the second surface, which is inside, hydrogen partial pressure on the first surface side (P _outside ) > hydrogen partial pressure on the second surface side ( P _inside ) and by disposing one or more tubular hydrogen separation membranes that discharge the hydrogen that has passed through the hydrogen separation membrane through the open part on the second side,

The length of the first tubular hydrogen separation membrane disposed in the first space ( ^1st room), the length of the second tubular hydrogen separation membrane disposed in the second space ( ^2nd room), ... , and the hydrogen recovery rate in the tubular hydrogen separation membrane having a length corresponding to the sum of the lengths of the nth tubular hydrogen separation membrane disposed in the n ^th room,

The hydrogen recovery amount in the first tubular hydrogen separation membrane, the hydrogen recovery amount in the second tubular hydrogen separation membrane, ... , and the total sum of the amount of hydrogen recovery in the nth tubular hydrogen separation membrane can be made larger.

At this time, each space is divided through a partition wall and the presence or absence of a catalyst for hydrogen generation reaction (or using a different catalyst combination for hydrogen production reaction), and the feed gas for the hydrogen production reaction (hydrocarbons such as methane) , carbon monoxide/moisture, ammonia), the hydrogen recovery rate that can be realized in the second-stage tubular hydrogen separation membrane module can be greatly increased by the hydrogen generation reaction, and the total amount of hydrogen recovered from the hydrogen-containing by-product gas can be amplified. there is.

In addition, the total amount of hydrogen recovery in the separation membrane module having the tubular hydrogen separation membrane according to the present invention is the amount of hydrogen recovery in the first stage module composed of the first tubular hydrogen separation membranes disposed in the first space, and the amount of hydrogen recovered in the second space. The hydrogen recovery amount in the second stage module composed of the second tubular hydrogen separation membranes disposed thereon, . . . , and the total sum of the hydrogen recovery amount in the n-th stage module composed of the n-th tubular hydrogen separation membranes disposed in the n-th space.

Therefore, as the hydrogen partial pressure difference decreases according to the length of the tubular hydrogen separation membrane, it is possible to overcome the disadvantage of not exhibiting the maximum performance of the separation membrane and increase the hydrogen recovery rate in one membrane module equipped with compact tubular hydrogen separation membranes.

The tubular hydrogen separation membrane is advantageous for large-capacity hydrogen production as it is easy to enlarge the area in the length and diameter directions when the reactor is installed. In addition, hydrogen-enriched gas may be collected in the inner space or pores of the tubular hydrogen separation membrane structure.

In the present invention, the gas discharged out of the separation membrane module by continuously flowing through each space separated from the inlet of the separation membrane module through the partition wall is a retentate gas from which hydrogen is removed through the hydrogen separation membrane, and a residual gas from which hydrogen is removed through the hydrogen separation membrane ( A retentate port through which retentate gas flow is discharged and a permeation port through which hydrogen collected in the inner space of the tubular hydrogen separation membrane is discharged may be designed to be distinguished.

For example, in the separation membrane module of the present invention, residual hydrogen remaining after the first hydrogen separation in the first space and/or hydrogen additionally generated through a hydrogen generation reaction in the second space are separated in the second space, and the first space and Hydrogen separated through the hydrogen separation membrane in the second space is collected in a collector in the separation membrane module, and unseparated residual gas may be discharged through a residual gas outlet (retentate port).

As illustrated in FIG. 3A, in the separation membrane module of the present invention, it is preferable to form turbulence around the tubular hydrogen separation membrane by generating spiral fluidization in the gas flow supplied to the first space through the module feed port. You don't have to be limited to this. However, mass transfer may be excellent by generating turbulent gas flow around the tubular hydrogen separation membrane through spiral fluidization.

In addition, in order to generate downward spiral fluidization in the gas flow supplied to the first space through the module inlet (feed port), as illustrated in FIG. 3A, the module inlet is disposed on the upper side or top of the separation membrane module, and After flowing through the first space through spiral fluidization, it is possible to flow in the direction of rising countercurrent to the second space.

In order to generate efficient descending spiral fluidization, the upper part of the first space starting at the top of the reactor where the module feed port is arranged may be in the form of a cone or a truncated cone.

In the separation membrane module of the present invention, a part of the driving principle of the cyclone is borrowed to give a vortex to the fluid supplied through the module inlet and introduce it into the first space, and the vortex effect in the first space It is introduced into the second space while rising in reverse flow, and the swirling flow in the first space can drive the hydrogen separation reaction to occur while winding the tubular hydrogen separation membrane.

The hydrogen separation membrane is a metal dense membrane, in which hydrogen molecules are adsorbed on the metal surface, dissociated into hydrogen atoms, hydrogen atoms move between the metal lattices, recombine into hydrogen molecules on the other side of the separation membrane, and desorb from the metal surface, so that hydrogen permeates. there is.

A typical example of a hydrogen separation membrane is a palladium-based metal dense separation membrane.

If the hydrogen separation membrane is a composite membrane composed of a porous support and a membrane layer, the thickness of the membrane, which is a limitation of the foil-type self-supported membrane, can be reduced, the hydrogen permeability can be significantly increased, and modularization for systemization is easy. In general, the hydrogen separation membrane may be implemented as a tubular separation membrane depending on the shape of the support.

For example, the hydrogen separation membrane may include a palladium-based dense membrane layer; optionally a diffusion barrier layer; And a porous support may be laminated.

At this time, the hydrogen separation membrane of the present invention may have a porous support on the first surface and a palladium-based dense film layer on the second surface, or a porous support on the second surface and a palladium-based dense film layer on the first surface. there is.

The palladium-based dense film may be palladium or a palladium alloy. The palladium alloy may be an alloy of Pd and one or more metals selected from the group consisting of Au, Ag, Cu, Ni, Ru and Rh. The palladium-based dense film may further include layers such as Pd/Cu, Pd/Au, Pd/Ag, and Pd/Pt in a multilayer structure. The palladium-based dense film may be formed to a thickness of 0.1 to 20 μm, preferably 1 to 10 μm. If the thickness is less than 0.1 μm, it is good because the hydrogen permeability is further improved, but it is difficult to manufacture a dense metal separator, which causes a problem in that the separator effect is lowered. When the thickness is greater than 20 μm, it can be densely formed, but the hydrogen permeability is relatively low, resulting in an increase in the number of separators. Among the palladium-based dense film coating methods, the electroless plating method is a technology capable of large-area coating regardless of the shape of the support.

Typically, as a hydrogen separation membrane of a palladium-based dense membrane, the operating temperature is 300 ~ 600 ℃.

In the palladium-based dense membrane, the hydrogen partial pressure P1 on the supply side, the hydrogen partial pressure P2 on the purification side, the film thickness t of the palladium-based dense membrane, and the membrane area of the palladium-based dense membrane are the main factors. That is, the hydrogen permeation amount Q per unit area is in the relationship of Equation 1 below.

In the above formula, A varies depending on the type of alloy film or operating conditions.

In a hydrogen permeable membrane based on a palladium alloy, a method of improving the hydrogen permeability by mainly thinning the membrane thickness is considered, but when the membrane thickness is thin, the mechanical strength is weakened. Since the amount of hydrogen permeation is affected by the difference in partial pressure of hydrogen, both thinning and strength are required. Therefore, a palladium alloy having a thin film thickness is used in combination with a porous support as described above to supplement mechanical strength. It is preferable to form pores on the surface of the porous support to have a size of 0.001 to 10 μm.

For example, a palladium-based dense membrane may be disposed on the outside of the tubular or cylindrical porous nickel support to collect hydrogen-enriched gas in the inner space or pores of the tubular or cylindrical porous nickel support.

On the other hand, when the porous support is metal during the manufacture of the hydrogen separation composite membrane, when a palladium-based dense membrane is formed directly on the porous metal support, a diffusion barrier occurs between Pd, a component of the palladium-based dense membrane, and the metal support, so that a diffusion barrier layer is formed between them. (diffusion barrier) is required. The diffusion barrier formed on the porous metal support, that is, the porous shielding layer can pass hydrogen through the pores/interstitial to prevent diffusion that may occur between palladium, which is a component of the palladium-based dense film, and the metal support. As such, it may be formed of a ceramic material. Non-limiting examples of the shielding layer include oxide-based, nitride-based, and carbide-based ceramics including one of Ti, Zr, Al, Si, Ce, La, Sr, Cr, V, Nb, Ga, Ta, W, and Mo. there is. Preferably, there are oxide-based ceramic materials such as TiO _y , ZrO _y , Al ₂ O _z (1<y≤2 or 2<z≤3).

As illustrated in FIG. 3B, two or more separation membrane modules having tubular hydrogen separation membranes designed to increase the hydrogen recovery rate according to the present invention may be connected in series, and at this time, the residual gas from which hydrogen is removed in the upstream separation membrane module A retentate port of may be connected to a feed port of a downstream membrane module.

As shown in FIG. 3B, the present invention can improve the hydrogen recovery rate by connecting the retentate port of the first membrane module and the feed port of the second membrane module when the multi-stage series is connected.

This is different from the existing separation cascade method in which the permeation port and the feed port are connected to increase hydrogen purity. In the existing permeation port-feed port connection method, stage-cut is determined and operated in each reactor module to match the concentration of the final product in each reactor module. Therefore, the recovery rate is determined in each reactor module, and the final recovery rate decreases as the number of modules connected in series increases.

A separation membrane module having a tubular hydrogen separation membrane according to the present invention can be used in a method for producing and/or purifying hydrogen. Accordingly, a reactant required for hydrogen production and/or a hydrogen-containing mixed gas may be supplied through the feed port of the separation membrane module.

A non-limiting example of a reactant required for hydrogen production supplied through the module inlet (feed port) is hydrogen-containing by-product gas, and a non-limiting example of the hydrogen-containing mixed gas supplied through the module inlet (feed port) is H There are mixed gases such as ₂ + CO ₂ , CH _{4 ,} CO, steam, and O ₂ .

In addition, when oxygen is included in the gas supplied through the inlet of the separation membrane module, an inert gas such as nitrogen may be additionally supplied to the reactor to prevent an explosion due to hydrogen combustion.

Furthermore, the membrane module equipped with a tubular hydrogen separation membrane according to the present invention can be used as a membrane reactor capable of chemical reactions by installing a catalyst for hydrogen generation reaction inside the membrane module.

According to the present invention, a membrane reactor equipped with a hydrogen separation membrane module designed to increase the hydrogen recovery rate is a hydrogen generation reaction by a catalyst filled in a shell space separated by a partition wall and hydrogen separation through a Pd-based membrane. may be happening at the same time.

At this time, the catalysts filled in the shell space separated by the partition wall include (i) reforming catalyst, (ii) reforming catalyst and water-gas shift reaction (WGS) catalyst, (iii) reforming catalyst and CO ₂ (iv) reforming catalyst, water gas shift catalyst and CO ₂ adsorbent, (v) water gas shift catalyst, (vi) water gas shift catalyst and CO ₂ adsorbent, (vii) ammonia cracking catalyst ( ammonia cracking catalyst) may be used (Figs. 2 and 4 to 6).

Carbon dioxide formed by the reforming reaction on the first side of the hydrogen separation membrane may be captured by a solid carbon dioxide absorbent.

[ Method for Producing Enriched Hydrogen from Hydrocarbon-Containing Gas ]

For example, in a membrane reactor equipped with a tubular hydrogen separation membrane module according to the present invention, a method for producing concentrated hydrogen from hydrocarbon-containing gas,

Separating hydrogen synthesized in the hydrocarbon reforming reaction through a tubular hydrogen separation membrane while performing the hydrocarbon reforming reaction in at least one space; and a step of separating hydrogen from a mixed gas containing hydrogen mainly in another space (at this time, WGS reaction can be performed). The boundary of each space may be partitioned by a partition wall, but steps 3 and 4 in FIG. 2 ) process, it can be separated according to whether the reforming reaction (WGS and/or reforming) proceeds as a forward reaction according to the hydrogen partial pressure in the hydrogen-containing mixed gas. In the latter case, the boundary of each space may change with time, and may be continuous in conjunction with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas. In addition, the boundary of the continuous space in conjunction with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas can be interpreted as a first space where hydrogen separation and removal mainly occurs rather than hydrogen generation reaction.

At this time, a hydrocarbon reforming reaction occurs on the first surface side of the hydrogen separation membrane, hydrogen generated from the first surface passes through the second surface, and hydrogen, which is a product of the hydrocarbon reforming reaction occurring on the first surface side, is removed, and the second surface side Hydrogen can be concentrated.

Among the hydrocarbon reforming reactions performed in at least one space, the representative methane reforming reaction is by selectively separating and removing only hydrogen among the products of Reaction Formula 1 (Steam Methane Reforming, SMR) and / or Reaction Formula 2 (water-gas shift reaction, WGS), It can be operated at a lower temperature (550 ~ 650 ℃) compared to the general reforming process (650 ~ 900 ℃), along with the improvement of reforming efficiency by LeCharlier's equilibrium wave principle.

As hydrogen is continuously removed from the reformed syngas through the hydrogen separation membrane, the process efficiency is improved and the reaction temperature is reduced according to Le Chatelier's principle. The hydrogen removal characteristics of such a hydrogen separation membrane structure are determined by the hydrogen permeability of the hydrogen separation membrane structure, and in particular, it is necessary to secure a hydrogen separation membrane with excellent performance.

Since the SMR reaction is an endothermic reaction, a method combining one or more of a gas burner, a blowing heater, or an induction method may be applied to supply a heat source.

The gas in the retentate from which hydrogen is separated and removed is a tail gas, and the thermal efficiency can be improved by using the heat generated through the combustion reaction in the entire process through a heat exchanger.

In the present invention, the second surface of the tubular hydrogen separation membrane may have a methanation catalyst activity of Reaction Formula 3 below to remove CO from the hydrogen-enriched gas passing through the hydrogen separation membrane.

[Scheme 3]

CO+ 3H ₂ ↔ CH ₄ + H ₂ O ΔH=-206 kJ/mol

In the present specification, the methanation reaction is a reverse reaction of the steam reforming (SMR) of methane in Reaction Formula 1, and may be represented by Reaction Formula 3, and the methanation catalyst means a catalyst for the methanation reaction.

When the porous support is disposed on the second surface and the palladium-based dense film layer is disposed on the first surface, the porous support may be a porous nickel support having methanation catalytic activity for removing CO.

In one embodiment of the present invention, on the retentate-side (the side where hydrogen is not permeable) based on the palladium-based dense membrane, the steam reforming reaction (SMR) of methane in Reaction Formula 1 and / or the water gas shift reaction (WGS) in Reaction Formula 2 H ₂ , CO and CO ₂ containing gas are formed, hydrogen enriched gas is formed while passing through the palladium-based dense membrane, and the methanation catalyst of Reaction Formula 3 on the permeate-side (the side through which hydrogen permeates) based on the palladium-based dense membrane By placing an active porous nickel support, the hydrogen-enriched gas can be freed of CO while a portion of the enriched H ₂ reacts with a small amount of CO to form a small amount of CH ₄ .

CO in the hydrogen enriched gas passing through the palladium-based dense membrane can be completely removed by methanation reaction on the porous nickel support. For example, in the tubular hydrogen separation membrane, a palladium-based dense membrane is disposed outside the tubular or cylindrical porous nickel support, and hydrogen-enriched gas from which CO is removed is collected in the inner space or pores of the tubular or cylindrical porous nickel support. Therefore, CO selective oxidation (Preferential Oxidation, PrOx) or purification process (PSA, Membrane, etc.) to remove residual CO is unnecessary.

Alternatively, by loading a methanation catalyst into a collector in the reactor that collects hydrogen separated and collected into the inner space of the tubular hydrogen separation membrane, at the outlet of the reactor where the hydrogen separated through the hydrogen separation membrane is discharged (permeation port) The carbon monoxide concentration can be lowered to 10 ppm or less.

According to one embodiment of the present invention, a membrane reactor designed to increase the hydrogen recovery rate is a shell-and-tube type membrane reactor in which a catalyst is mounted inside the membrane module and capable of chemical reactions.

A catalyst for methane reforming reaction in the shell and optionally a catalyst for water-gas shift reaction (WGS) and / or a carbon dioxide absorbent are filled,

Hydrogen formed by Reaction Formula 1 and Reaction Formula 2 from the gas containing methane and water vapor under the catalyst for methane reforming reaction in the shell and optionally the catalyst for WGS passes through the tubular hydrogen separation membrane structure and is concentrated or separated inside the tube,

Optionally, the carbon dioxide formed by Scheme 2 under the catalyst for WGS in the shell may be captured by the carbon dioxide absorbent packed in the shell.

In the methane gas reforming reaction (SR) based on Reaction Equation 1 (Steam Methane Reforming, SMR) and Reaction Equation 2 (water-gas shift reaction, WGS), when a hydrogen separation membrane and a dry carbon dioxide absorbent are used simultaneously (SR-SEMR), the reaction equation Among the products of Equation 1 and Reaction 2, not only hydrogen (H ₂ ) but also carbon dioxide (CO ₂ ) are selectively removed, and a forward reaction than when only hydrogen is removed in the methane gas reforming reaction (SR-MR) using only a hydrogen separation membrane without a carbon dioxide absorbent can be further promoted to maximize process efficiency. In this case, the present invention simultaneously applies a palladium hydrogen separation membrane and dry carbon dioxide absorbent technology to the methane gas wet reforming reaction process to lower the reaction temperature while simultaneously performing high efficiency hydrogen production and carbon dioxide capture. A highly efficient hybrid device and process can be provided. there is.

To explain further, the two reactions occur continuously in an atmosphere in which steam is in excess of methane. In the methane wet reforming reaction of Reaction Equation 1, selectively separating hydrogen, which is a product, with a membrane (Memb.) not only improves the forward reaction of Reaction Equation 1. In addition, when carbon dioxide, a product of the WGS reaction of Scheme 2, is captured using a dry absorbent (Σ(s)) and hydrogen, a product thereof, is separated through a membrane (Memb.), the forward reaction of Scheme 2 is also improved. Therefore, if the reforming reaction is further improved by simultaneously capturing/separating carbon dioxide and hydrogen, which are the main components of the products of Reaction Formulas 1 and 2, occurring in the same reactor space, the reaction temperature is increased compared to the membrane-enhanced reforming reaction and the sorption-enhanced reforming reaction. can be significantly lowered. Such a hydrogen separation membrane/carbon dioxide absorber hybrid reformer technology is a representative example of the present invention. Therefore, in the following, one embodiment of the present invention is often abbreviated as hydrogen separation membrane/carbon dioxide absorber hybrid reformer technology.

The hydrogen separation membrane/carbon dioxide absorber hybrid reformer technology (SR-SEMR) according to the present invention continuously removes hydrogen and carbon dioxide, which are products thereof, simultaneously with the reforming reactions of Schemes 1 and 2, thereby breaking the thermodynamic equilibrium according to the LeCharlier principle. It can be operated at around 500℃. Therefore, 1) superior operation efficiency compared to traditional methane reforming reactors, 2) low reaction temperature of 500 °C, it is possible to construct an economical reactor by using low- and medium-temperature materials, and 3) economical process due to low post-refining load. Easy to operate.

In addition, compared to the membrane reformer (SR-MR) operated at 300 ° C to 520 ° C, preferably 400 ° C to 500 ° C, 1) the reforming temperature can be further reduced by more than 50 ° C due to the acceleration of the forward reaction due to the collection of CO ₂ , the product. Fuel consumption is reduced by about 10%, and 2) CO and CO ₂ in the retentate are removed by the carbon dioxide absorbent, so the concentration of unseparated H ₂ and CH ₄ is improved, reducing process costs by about 5% or more. This excellent process configuration is possible.

Furthermore, since the hydrogen separation membrane/carbon dioxide absorber hybrid reformer apparatus and process according to the present invention can be operated at 300 ° C to 520 ° C, preferably 400 ° C to 500 ° C, high-temperature by-product gas generated in the steelmaking process is reduced to around 500 ° C Phosphorus Coke Oven Gas (COG) can be applied as an additional hydrogen production/refining and CO ₂ capture device without a separate heat source supply.

According to the present invention, in the hydrogen production and purification apparatus designed to simultaneously perform methane gas-based high-efficiency hydrogen production and carbon dioxide capture, the reaction temperature of reaction formulas 1 and 2 on the first side of the tubular hydrogen separation membrane, that is, the operating temperature is 300 °C to 520 °C, preferably 400 °C to 500 °C.

Coke Oven Gas (COG), a by-product gas from the use of coke, has hydrogen and methane as its main components and has a gas temperature of around 500 ℃, so it can produce high-purity hydrogen through the SR-SEMR reaction according to the present invention without inputting an external heat source or energy cost. can be produced, and CO ₂ in COG gas can be captured.

Therefore, the reactor according to the present invention can use high-temperature by-product gas of 500 ° C ± 100 ° C generated in the steelmaking process as a methane-containing gas, and can produce high-purity hydrogen while capturing CO ₂ in the high-temperature by-product gas.

According to the present invention, the main core materials of the reactor capable of capturing carbon dioxide as well as hydrogen production are (a) a hydrogen separation membrane, (b) a solid carbon dioxide absorbent, and (c) a catalyst for methane reforming reaction.

The catalyst for methane reforming reaction includes a catalyst for performing steam methane reforming (SMR) of methane in Reaction Scheme 1 and a catalyst for performing water-gas shift reaction (WGS) in Reaction Scheme 2, It may be a catalyst that performs both the steam reforming (SMR) of methane of Reaction Scheme 1 and the water gas shift reaction (WGS) of Reaction Scheme 2.

The most commonly used catalyst for steam reforming reaction (SMR) is Ni-base Ni/Al ₂ O _3. Precious metal catalysts such as Ru and Pt are expensive, but have high reaction activity and excellent durability, making Ru/Al ₂ O ₃ is applied as a commercial catalyst. Catalysts for water gas shift reaction (WGS) are commercially available Fe ₂ O ₃ /Cr ₂ O ₃ and Cu/ZnO/Al ₂ O ₃ catalysts.

In the present invention, the catalyst for methane reforming reaction that can be filled on the first surface side (eg, in the shell) of the tubular hydrogen separation membrane can be any type of catalyst capable of reforming reaction, such as pellet form, bead form, foam form, and powder form. . More preferably, it may be a metal foam-based reforming catalyst. The use of a metal foam catalyst can maximize heat transfer and mass transfer effects and overcome the hydrogen recovery rate limit due to the concentration gradient, which can be a problem in tubular membranes. The key to constructing a separator reactor using metal foam is to overcome the mutual diffusion problem caused by contact between the separator and the metal foam when the metal foam catalyst is mounted on the outside of the separator. It can be solved by inserting a rod capable of blocking the coating material and then coating the catalyst.

The metal foam catalyst usable in the present invention is one or more metals selected from the group consisting of aluminum, iron, stainless steel, nickel, iron-chromium-aluminum alloy (Fecralloy), nickel-chromium alloy, copper and copper-nickel alloy. A catalyst for methane reforming reaction may be coated on the surface of the formed metal structure in the form of a foam, but is not limited thereto.

The carbon dioxide absorbent used in the present invention is a dry absorbent that is a solid rather than a liquid.

In the hydrogen separation membrane/CO ₂ absorber hybrid reforming reaction of the present invention, the manufacturing and molding process for the CO ₂ absorber should be considered to enable continuous operation with CO ₂ absorption and regeneration process under high-temperature and high-pressure reaction conditions in the presence of moisture.

In the present invention, the solid carbon dioxide absorbent may react with carbon dioxide to be converted into a stable compound, and may be regenerated into the original compound by degassing the carbon dioxide again in a regeneration reactor.

When applying a fluidized bed reactor, the shape of the absorbent may be spherical for easy circulation replacement, and it is preferable that the inside is porous to improve absorption capacity. In addition, it may be required to improve the thermal and physical stability and abrasion resistance of the absorbent.

The carbon dioxide absorbent applicable to the hydrogen separation membrane/CO ₂ absorbent hybrid reformer process of the present invention is preferably capable of selectively removing carbon dioxide generated as a reaction by-product in a high-temperature, high-pressure syngas composition. In addition, it is desirable to have a high absorption/regeneration rate at the same time as a high absorption capacity.

A WGS catalyst or a membrane reactor composed of a WGS catalyst and a CO ₂ absorber can produce hydrogen in conjunction with coal, biomass, and waste gasification processes.

On the other hand, as illustrated in FIGS. 4 to 6, a reactor having a tubular hydrogen separation membrane module according to the present invention performs a hydrogen generation reaction while removing and recovering hydrogen from a hydrogen-containing by-product gas through a hydrogen separation membrane. - As a tubular hydrogen amplification and purification device,

A catalyst for methane reforming reaction in the shell and optionally a WGS catalyst and / or a carbon dioxide absorbent are filled,

Hydrogen formed by Reaction Formula 1 and Reaction Formula 2 from methane and water vapor-containing gas under the catalyst for methane reforming reaction in the shell passes through the tubular hydrogen separation membrane and is concentrated or separated inside the tube,

Carbon dioxide formed by Scheme 2 in the presence of a catalyst for methane reforming reaction in the shell can be captured by the carbon dioxide absorbent filled in the shell.

Therefore, the shell-and-tube type hydrogen amplification and purification apparatus according to the present invention can provide a compact 50 to 5,000 Nm ³ /h class small and medium-sized hydrogen production plant.

Since the steam reforming reaction of methane in Scheme 1 occurring in the shell is an endothermic reaction, a tube for exothermic reaction or a heat exchanger for exothermic reaction may be provided at the center.

In the shell-and-tube type membrane reformer, one or more tubes for exothermic reaction or heat exchanger for exothermic reaction disposed inside the reactor, and a plurality of tube-type hydrogen tubes arranged in a circumferential shape outside the tube for exothermic reaction or heat exchanger for exotherm It may have a structure including a separation membrane.

In the membrane reforming reactor of the present invention, the top or bottom of the hydrogen separation membrane for tubes may be fixed to the shell-and-tube type reactor by a tube sheet.

Since the methane reforming reaction of Scheme 1 is a large endothermic reaction, the necessary heat can be supplied by the catalytic combustion reaction of the combustion gas with air in an exothermic reaction tube disposed at the center of the shell-and-tube reactor.

In the shell-and-tube type membrane reforming reactor of the present invention, the temperature (T ₁ ) of the tube for exothermic reaction or the heat exchanger for exothermic reaction is higher than the temperature (T ₂ ) of the catalyst layer filled in the shell, and for the exothermic reaction disposed in the center. Syngas may be formed by an endothermic reaction by a catalyst for methane reforming reaction in the shell while heat moves radially outward from the tube or heat exchanger for heat generation.

That is, the shell-and-tube type membrane reforming reactor according to one embodiment of the present invention has a heating means inside so that heat is transferred from the inside (T ₁ ) to the outside (T ₂ , T ₁ > T ₂ ), Thermal efficiency is excellent. At this time, the heating unit may be provided with a combustion catalyst to supply heat through an exothermic reaction, but may also include a heat transfer unit (T ₁ ). The exothermic reaction tube may be filled with at least one catalyst capable of catalyzing an exothermic reaction. A catalyst capable of catalyzing an exothermic reaction usable in the present invention includes a combustion catalyst. Specifically, as a combustion catalyst usable in the present invention, a catalyst in which Pt/Rh is supported on cordierite may be used, but is not limited thereto.

In the shell-and-tubular membrane reforming reactor of the present invention, the bottom of the tubular hydrogen separation membrane can be sealed by bonding the metal tube and tube sheet welded to the end of the filter by utilizing the metal tube characteristics or by using a metal fitting . In addition, the unit module can be completed by assembling the tube sheet, module cover, and module body equipped with the separator in a flange method.

The main use of the reforming reactor equipped with a tubular hydrogen separation membrane module according to the present invention described above is useful for processes requiring low-cost hydrogen such as hydrogen reduction steelmaking. Therefore, CO ₂ emissions in the hydrogen reduction process can be reduced by 15%. In addition, it can be used for hydrogen stations capable of reducing greenhouse gases.

According to the present invention, in a hydrogen amplification membrane reactor that performs a hydrogen generation reaction (wet reforming reaction and water gas shift reaction) while removing and recovering hydrogen from a hydrogen-containing by-product gas through a hydrogen separation membrane, the main components are hydrogen and hydrocarbons (CH ₄ , C ₂ H ₄ , etc.), when using Coke Oven Gas (COG), as shown in Table 2, the flow rate and CO / CH ₄ / C ₂ H ₄ of a certain composition of coke oven gas By adjusting the conversion rate, the total hydrogen production as a result of hydrogen amplification can be achieved by more than three times the hydrogen flow rate in the coke oven gas.

Furthermore, the product, hydrogen-enriched gas, can be used as fuel for fuel cells or as hydrogen in ammonia synthesis, oil refining processes, smelting processes, polysilicon manufacturing processes, semiconductor manufacturing processes, or LED manufacturing processes.

[ Method of producing enriched hydrogen from ammonia-containing gas ]

In a separation membrane reactor equipped with a tubular hydrogen separation membrane module according to the present invention, a method for producing concentrated hydrogen from ammonia-containing gas is also carried out in at least one space when the ammonia cracking reaction corresponding to the hydrocarbon reforming reaction is performed, the above-mentioned hydrocarbon-containing It can exhibit the same characteristics as the method for producing enriched hydrogen from gas.

[ Electrical energy generating device interlocked with fuel cell ]

Furthermore, the present invention provides a hydrogen amplification membrane reactor according to the present invention; And it is possible to provide an electrical energy generating device interlocked with a fuel cell using the hydrogen enriched gas provided from the hydrogen amplification membrane reactor as fuel.

According to one embodiment of the present invention, when the methanation reaction of Reaction Formula 3 is linked in the pores of the porous nickel support located on the permeate-side through which hydrogen permeates after the hydrogen permeation membrane process in the palladium-based dense membrane, the palladium-based dense membrane defect It is possible to control the CO concentration permeated through the defect to less than 20ppm, so it can be used as a fuel for PEMFC fuel cells using catalysts in which CO acts as a catalyst poison without a separate purification device.

According to the present invention, the shell-and-tube type hydrogen amplification membrane reactor equipped with a tubular hydrogen separation membrane module has excellent mass transfer due to easy formation of turbulence due to spiral fluidization, and can improve process efficiency by minimizing heat loss required for reaction/separation. In addition, by using the space in the shell where the tubular hydrogen separation membrane is mounted as a partition wall, it is divided into 1 ^st room and 2 ^nd room, and the hydrogen partial pressure difference is reduced according to the length of the separation membrane. The hydrogen recovery rate can be increased. In addition, the present invention can not only amplify the total amount of hydrogen recovered from the hydrogen-containing by-product gas through the hydrogen generation reaction from the hydrogen-containing by-product gas, but also significantly increase the hydrogen recovery rate.

1 is a hydrogen amplification membrane reactor in which spaces are divided in the longitudinal direction of a shell-and-tube type separation membrane module and a tubular hydrogen separation membrane according to an embodiment of the present invention and a catalyst for hydrogen generation reaction is provided in one space.
2 illustrates processes in which a hydrogen amplification separation membrane reactor equipped with a separation membrane module and a catalyst for hydrogen generation reaction can be used according to the present invention. When carbon dioxide is included among these, the reforming reaction/WGS reaction can be further improved by removing some or all of the carbon dioxide before supplying the by-product gas to the membrane reactor. Non-limiting examples of carbon dioxide removal methods include a separation membrane method, a dry absorption method, and a wet absorption method.
Figure 3a is a conceptual diagram for explaining the principle of operation of a separation membrane module having a tubular hydrogen separation membrane according to one embodiment (upper view) of configuring a two-stage tubular hydrogen separation membrane module using a partition wall and one embodiment of the present invention (lower view) )am.
Figure 3b is an embodiment in which two or more tubular hydrogen separation membrane modules designed to increase the hydrogen recovery rate are connected in series according to one embodiment of the present invention.
4 to 6 are various embodiments of a hydrogen amplification membrane reactor equipped with a shell-and-tube type membrane module and a hydrogen generation reaction catalyst according to one embodiment of the present invention.

Hereinafter, the present invention will be described in more detail through examples. However, the following examples are only intended to clearly illustrate the technical features of the present invention, but do not limit the protection scope of the present invention.

Example 1: Method for constructing a catalyst for hydrogen generation reaction according to the height of the separation membrane

In the shell-and-tube type hydrogen amplification membrane reactor equipped with the tubular hydrogen separation membrane shown in FIG. 1,

(1) When reforming, WGS or reforming and WGS mixed catalysts are installed only in Zone 2, Zone 1 : Zone 2 = 0 : 1 ~ 1 : 0 (separator height), or

(2) When the WGS catalyst is installed in Zone 1 and the reforming catalyst is installed in Zone 2, Zone 1 : Zone 2 = 0 : 1 ~ 1 : 0 (separator height), or

(3) In the case of gas containing ammonia, Zone 1 : Zone 2 = 0 : 1 ~ 1 : 0 (separator height) can be configured, and Zone 1 : Zone 2 = 0 : 1 (separator height) is preferable. In addition, if necessary, additional catalysts can be installed on the upper part of Zone 1.

Example 2: By-product gas hydrogen amplification experiment

In a shell-and-tube type hydrogen amplification membrane reactor equipped with a tubular hydrogen separation membrane shown in FIG. 1, the reaction was performed under the conditions shown in Table 3 below.

Some of the hydrogen in the mixed gas supplied from the feed point was removed through the membrane in Zone 1. At this time, due to the breakthrough of the SMR reaction equilibrium due to hydrogen removal, hydrogen production capacity was generated from methane and carbon monoxide. In Zone 2, methane wet reforming and WGS reaction were further performed.

The results are shown in Table 4.

As can be seen in Table 4, the flow rates of methane (CH ₄ ) and carbon monoxide (CO) decreased from 510 ml/min to 314 ml/min and from 313 ml/min to 20 ml/min, respectively, and hydrogen ( H ₂ ) Flow rate was amplified from 2970 ml/min to 4026 ml/min, and 4011 ml/min out of 4026 ml/min was separated and purified through the membrane reactor shown in FIG. 1 .

Furthermore, in the case of the flow rate of carbon dioxide (CO ₂ ) in a mixed gas with hydrogen through the shell-and-tube type hydrogen amplification membrane reactor of FIG. Confirmed possible.

Claims (15)

While removing and recovering hydrogen from hydrogen-containing by-product gas through a hydrogen separation membrane, As a hydrogen amplification membrane reactor for performing a hydrogen generation reaction,
Based on the gas flow direction connected from the module inlet (feed port) to the outlet, the first space ( ^1st room), the second space ( ^2nd room), ... , having a separation membrane module divided into n ^th room (n ≥ 2),
In the first space, some or all of the hydrogen is removed and recovered from the hydrogen-containing by-product gas through the hydrogen separation membrane, and the forward reaction can proceed in the second space where the hydrogen generation reaction is performed by breaking the thermodynamic equilibrium according to LeCharlier's law. is designed to be
The second space is designed to remove and recover some or all of the hydrogen through a hydrogen separation membrane while performing a hydrogen generation reaction from a by-product gas from which hydrogen is partially or completely removed in the first space. The method of claim 1, wherein the boundary of each space of the separation membrane module is (i) partitioned by a partition wall, and/or (ii) depending on whether the hydrogen generation reaction proceeds as a forward reaction in conjunction with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas. A hydrogen amplification membrane reactor characterized by being formed. According to claim 1, each space of the membrane module (i) presence of a catalyst for hydrogen generation reaction; (ii) whether the hydrogen generation reaction proceeds as a forward reaction in conjunction with the hydrogen partial pressure gradient in the hydrogen-containing mixed gas; (iii) the use of different combinations of catalysts for hydrogen production; (iv) different hydrogen production reaction conditions and / or (v) a hydrogen amplification membrane reactor characterized by being separated from other adjacent spaces by partition walls. The hydrogen-amplified membrane reactor according to claim 1, wherein the membrane module is a shell-and-tube membrane module equipped with a tubular hydrogen membrane. The method of claim 1, wherein at least the second space is filled and / or coated with a catalyst for hydrogen generation reaction,
The catalyst is a catalyst for a wet reforming reaction, a catalyst for a partial oxidation reaction, a catalyst for an autothermal reforming reaction, a catalyst for a water gas shift reaction, and / or a catalyst for ammonia decomposition. ◈Claim 6 was abandoned when the registration fee was paid.◈ The method of claim 4, wherein the gas discharged out of the reactor by continuously flowing through each space from the module inlet is a retentate gas from which hydrogen has been removed through a hydrogen separation membrane,
Designed to distinguish between a retentate port through which hydrogen is removed through the hydrogen separation membrane and a permeation port through which hydrogen collected in the inner space of the tubular hydrogen separation membrane is discharged become,
A hydrogen amplification membrane reactor characterized in that the hydrogen separated through the hydrogen separation membrane in each space is collected in a collector in the reactor and then discharged. ◈Claim 7 was abandoned when the registration fee was paid.◈ The method of claim 4, wherein the fluid supplied through the module inlet is introduced into the first space by giving a vortex, and is introduced into the second space by a vortex effect in the first space. make it,
The swirling flow in the first space winds the tubular hydrogen separation membrane and drives the hydrogen separation membrane reactor. ◈Claim 8 was abandoned when the registration fee was paid.◈ The hydrogen-amplified membrane reactor according to claim 4, wherein one or more barrier ribs are concentrically disposed inside the shell-and-tube module, and a tubular hydrogen separation membrane is provided in a space separated through the barrier rib. The hydrogen amplification membrane reactor from by-product gas according to claim 1, wherein the hydrogen separation membrane is a palladium-based hydrogen separation membrane. Based on the gas flow direction connected from the module inlet (feed port) to the outlet, the first space ( ^1st room), the second space ( ^2nd room), ... , a hydrogen amplification process of performing a hydrogen generation reaction from a hydrogen-containing by-product gas in a separation membrane reactor equipped with a separation membrane module divided into n ^th room (n ≥ 2),
Removing and recovering some or all of hydrogen from a hydrogen-containing by-product gas through a hydrogen separation membrane in the first space so that the forward reaction can proceed in the second space where the hydrogen production reaction is performed by breaking the thermodynamic equilibrium according to LeCharlier's law Step 1; and
A second step of removing and recovering some or all of the hydrogen through a hydrogen separation membrane while performing a hydrogen generation reaction in the second space from the by-product gas from which hydrogen is partially or entirely removed in the first step.
A method for producing hydrogen through hydrogen amplification of by-product gas, characterized in that it comprises a. ◈Claim 11 was abandoned when the registration fee was paid.◈ The method for producing hydrogen through hydrogen amplification of by-product gas according to claim 10, which is performed in the hydrogen amplification membrane reactor according to any one of claims 1 to 9. 11. The method of claim 10, wherein, when the hydrogen-containing by-product gas contains carbon dioxide, hydrogen production through hydrogen amplification of the by-product gas further comprising removing some or all of the carbon dioxide before supplying the by-product gas to the membrane reactor. method. 11. The method of claim 10, wherein the hydrogen-containing by-product gas is produced from the iron and steel industry, the petrochemical industry, the ammonia emission industry containing hydrogen, and the biogas emission industry. ◈Claim 14 was abandoned when the registration fee was paid.◈ 11. The method for producing hydrogen according to claim 10, wherein the hydrogen-containing by-product gas is provided from a high-temperature by-product gas of 500°C ± 100°C generated in a steelmaking process. The hydrogen amplification membrane reactor according to any one of claims 1 to 9; and a fuel cell using the hydrogen-enriched gas provided from the hydrogen-amplified membrane reactor as fuel.

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