KR102621148B1 - Thermochemical redox cycle combined with biomass gasification process for hydrogen production - Google Patents

Abstract

The present application relates to a hydrogen dual generation process that generates hydrogen through an upper cycle process and a lower cycle process, and a hydrogen dual generation device that drives the same.

Description

Hydrogen generation thermochemical redox cycle combined with biomass gasification process {THERMOCHEMICAL REDOX CYCLE COMBINED WITH BIOMASS GASIFICATION PROCESS FOR HYDROGEN PRODUCTION}

The present application relates to a hydrogen dual generation process that generates hydrogen through an upper cycle process and a lower cycle process, and a hydrogen dual generation device that drives the same.

Two mega trends are driving greenhouse gas reductions in modern society. The first trend is grid renewal. Photovoltaic power (PV) is now one of the cheapest methods of power generation in the U.S. due to the rapid decline in solar module prices, which fell from ~$4/W in 2008 to $0.2/W in 2019. The second trend is vehicle electrification. In 2019, the number of battery electric vehicles worldwide reached 4.79 million and is expected to increase rapidly in the future. This is mainly due to the continued decline in lithium-ion battery prices from $1,183/kWh in 2010 to $156/kWh in 2019.

However, some sectors find it difficult to reduce greenhouse gas emissions with these two major efforts. For example, the aviation or shipping sectors, which produced 5% of global _CO2 emissions from all fossil fuel and industrial sources in 2014, require high energy density chemical fuels due to long travel distances and limited space. The iron and cement industries, which produced 9% of global _CO2 emissions from all fossil fuels and industrial sources in 2014, also require large amounts of chemical fuels to provide reducing agents as well as heat supply.

Hydrogen has been seen as a key component in dramatically reducing greenhouse gas emissions from these sectors because it can directly replace existing chemical fuels in these sectors, such as diesel in ships or coal in steelmaking. It can also be further processed into advanced hydrocarbons, such as jet fuel, for utilization in these sectors without changes to infrastructure. However, since hydrogen is a secondary energy source like electricity that must be produced from another primary energy source, greenhouse gas emissions throughout the entire process are highly dependent on the production route.

The most frequently used technology for hydrogen production is steam methane reforming. The cost of hydrogen production through this route is relatively inexpensive at ~$2/kg-H ₂ , but carbon dioxide emissions are unavoidable due to the presence of carbon in the feedstock. Another representative route is water decomposition. This route is desirable because the water does not contain any carbon, but the water decomposition reaction is highly endothermic and requires a lot of energy input.

A thermochemical redox cycle was proposed to solve the above-mentioned problems. By having additional reactants, the water splitting reaction can be decomposed into oxygen and hydrogen evolution reactions and the required temperature can also be lowered. So far, metal oxides (MO _x ) have been studied as the additional reactants in thermochemical redox cycles. In particular, metal oxides with oxygen vacancies in the lattice through non-stoichiometric oxygen reduction have been mainly used in this technology because they do not undergo phase change and are easy to separate products that are good for cycling. The oxygen evolution reaction and hydrogen evolution reaction of metal oxide can be expressed as equations (3) and (4), respectively.

The amount of oxygen reduction (δ) is determined by thermodynamic equilibrium, and the higher the temperature and the lower the oxygen pressure, the greater the amount of oxygen reduction. Therefore, the reduction reaction is performed at higher temperature and lower oxygen pressure to increase δ, and the oxidation reaction is performed at lower temperature and higher oxygen pressure to decrease δ. In the case of Ceria (CeO ₈ ), a benchmark material used in this technology, reduction and oxidation reactions are generally performed under conditions of 1 mbar of oxygen pressure and 1,500°C, and ambient pressure and 900°C, respectively. do.

Although the temperature of the thermochemical redox cycle is much lower than that of direct pyrolysis, it is still high, so high-temperature heat must be supplied to the metal oxide. Therefore, among various renewable heat sources, concentrated solar heat has been studied the most. The sunlight concentrated by the heliostat reaches the reactor and is absorbed by the metal oxide in the reactor. Metal oxides undergo a thermochemical redox cycle consisting of four stages: reduction reaction, temperature decrease, oxidation reaction, and temperature increase (Figure 1): First, the metal oxide is reduced through an endothermic reduction reaction at high temperature and low oxygen pressure to produce oxygen. emits. Second, the temperature of the reduced metal oxide is lowered from the reduction temperature to the oxidation temperature. Third, the reduced metal oxide reacts with water to be reoxidized and generates hydrogen through an exothermic oxidation reaction. Fourth, prepare to repeat the first step by raising the temperature of the metal oxide from the oxidation temperature to the reduction temperature. The concentrated solar energy is utilized in the reduction reaction and temperature rise steps.

However, experimental verification tests using ceria showed that the number of cycles that can be performed per day is limited to 6 to 8, and the efficiency is not very high at about 5 to 6%.

J.W. Kim et al., “Thermochemical cycles for hydrogen production from water”, Journal of Energy Engineering, vol. 15, No. 2, pp. 107~117, 2006.

The present application seeks to provide a hydrogen dual generation process and a hydrogen dual generation device in which a bottom cycle process is combined with a thermochemical redox cycle process.

However, the problem to be solved by the present application is not limited to the problems mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the description below.

A first aspect of the present disclosure is a top cycle process comprising a thermochemical redox cycle; and a bottom cycle process using waste heat and pure oxygen generated in the top cycle, wherein both the top cycle process and the bottom cycle process generate hydrogen.

A second aspect of the present application includes an upper cycle device that drives a thermochemical redox cycle process; and a lower cycle device using waste heat and pure oxygen generated in the upper cycle device, wherein both the upper cycle device and the lower cycle device generate hydrogen. Provided is a dual hydrogen production device that drives the process.

In our system, pure oxygen and waste heat generated in the upper cycle process are not discarded but are transferred to the lower cycle process. The transferred waste heat is of high quality at a very high temperature and produces hydrogen in combination in the top and bottom cycle processes, so the hydrogen productivity of the hydrogen dual production process of the present invention is highly economical.

Biomass is a biological organism that synthesizes organic matter by receiving solar energy and includes animals, wood, straw, charcoal, etc. The type of biomass supplied from outside to the bottom cycle process is not limited to one species but has a wide range. Since there are no restrictions on the biomass raw materials for the bottom cycle process, there is an advantage that it can be used in various places and regions without facing problems with raw material supply and demand.

Figure 1 is a schematic diagram of a thermochemical redox cycle using concentrated solar irradiation.
Figure 2 is a graph showing the efficiency of the thermochemical redox cycle process according to solid heat recovery efficiency.
Figure 3 is a schematic diagram of a conventional thermochemical redox cycle without a bottom cycle process and a thermochemical redox cycle with the addition of a bottom cycle process.
Figure 4 is a schematic diagram of a double hydrogen production device.
Figure 5 is a diagram showing the algorithm of system simulation.

Hereinafter, with reference to the attached drawings, implementation examples and embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present application may be implemented in various different forms and is not limited to the implementation examples and examples described herein. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout this specification, when a part is said to be “connected” to another part, this includes not only the case where it is “directly connected,” but also the case where it is “electrically connected” with another element in between. do.

Throughout this specification, when a member is said to be located “on” another member, this includes not only the case where the member is in contact with the other member, but also the case where another member exists between the two members.

Throughout the specification of the present application, when a part “includes” a certain element, this means that it may further include other elements rather than excluding other elements, unless specifically stated to the contrary.

As used herein, the terms “about,” “substantially,” and the like are used to mean at or close to a numerical value when manufacturing and material tolerances inherent in the stated meaning are presented, and to aid understanding of the present application. It is used to prevent unscrupulous infringers from unfairly exploiting disclosures in which precise or absolute figures are mentioned.

The terms “step of” or “step of” as used throughout the specification herein do not mean “step for.”

Throughout this specification, the term "combination(s) thereof" included in the Markushi format expression means a mixture or combination of one or more selected from the group consisting of the components described in the Markushi format expression, It means containing one or more selected from the group consisting of the above components.

Throughout this specification, description of “A and/or B” means “A or B, or A and B.”

Hereinafter, embodiments of the present application have been described in detail, but the present application may not be limited thereto.

A first aspect of the present disclosure is a top cycle process comprising a thermochemical redox cycle; and a bottom cycle process using waste heat and pure oxygen generated in the top cycle, wherein both the top cycle process and the bottom cycle process generate hydrogen.

In one embodiment of the present application, the bottom cycle process may include a biomass gasification process that generates hydrogen. In one embodiment of the present application, the bottom cycle process may include a process driven by an endothermic reaction at about 800°C to about 1000°C. In one embodiment of the present application, the bottom cycle process may include a biomass gasification process driven by an endothermic reaction at about 800°C to about 1000°C. Specifically, the waste heat is generated by the operation of the upper cycle process and is reused in the lower cycle process operated at about 800°C to about 1000°C, so the present invention can have the efficiency and economic feasibility of dual hydrogen production.

In one embodiment of the present application, the top cycle process may be a thermochemical redox cycle process according to the oxidation-reduction reaction of metal oxide.

In one embodiment of the present application, the upper cycle process may be driven based on a regenerative heat source, but may not be limited thereto. For example, the renewable heat source may use one or more selected from solar heat, biogas-based heat source, waste gas-based heat source, and waste heat.

In one embodiment of the present application, the bottom cycle process may include a biomass gasification process using the waste heat, a water gas conversion (WGS) process, and a pressure swing adsorption process (PSA). Here, the biomass gasification process, water gas conversion process, and pressure swing adsorption process may be performed in a series of sequences.

In one embodiment of the present application, the bottom cycle process may further include a cooling process between the biomass gasification process and the water gas conversion process.

In one embodiment of the present application, the upper cycle process may further include a thermal energy storage process for storing waste heat generated in the upper cycle process, but may not be limited thereto.

Referring to FIG. 4, a schematic design of the dual hydrogen production process of the present application can be confirmed. In one embodiment of the present application, when the top cycle process produces hydrogen at a flow rate of about 0.1 mol/s to about 10 mol/s, the bottom cycle process produces hydrogen at a flow rate of about 1 mol/s to about 15 mol/s. When biomass is externally supplied at a flow rate, the bottom cycle process can generate hydrogen at a flow rate of about 1 mol/s to about 20 mol/s. As an example of the present application, when the upper cycle process produces hydrogen at a flow rate of about 1 mol/s and biomass is externally supplied to the lower cycle process at a flow rate of about 9.16 mol/s, the lower cycle process produces about 14.617 mol/s. Hydrogen can be produced at a flow rate of mol/s. This is approximately 14 times more than the hydrogen production amount of the upper cycle process, and it can be confirmed that our dual hydrogen production process is a very highly efficient process that requires a large amount of hydrogen and is recognized for its economic feasibility.

A second aspect of the present application includes an upper cycle device that drives a thermochemical redox cycle process; and a lower cycle device using waste heat and pure oxygen generated in the upper cycle device, wherein both the upper cycle device and the lower cycle device generate hydrogen. Provided is a dual hydrogen production device that operates.

Detailed description of parts overlapping with the first aspect of the present application has been omitted, but the description of the first aspect of the present application can be applied equally even if the description is omitted in the second aspect of the present application.

In one embodiment of the present application, the top cycle device may include one or more thermochemical redox reactors. Here, the thermochemical redox reactor receives heat from a heat source and performs an endothermic reduction reaction to convert MO _x-δox into MO _x-δrd and increase the temperature of the solid reactor.

In one embodiment of the present application, a thermal energy storage device that stores waste heat generated in the upper cycle device may be further included.

In one embodiment of the present application, the upper cycle device may further include a heat recovery device, but may not be limited thereto. Here, the heat recovery device may be a heat exchanger, and the heat exchanger may include one or more heat exchangers.

In one embodiment of the present application, the upper cycle device may further include one or more pumps, which may be water pumps and/or vacuum pumps.

In one embodiment of the present application, the bottom cycle device may include a gas generating device that performs biomass gasification. Here, the gas generating device may be a device that reacts biomass and water vapor by receiving waste heat and pure oxygen from the upper cycle device.

In one embodiment of the present application, the bottom cycle device may further include a water gas conversion reactor and a pressure fluctuation adsorption vessel. Here, the water gas conversion reactor is a device that performs a reaction to convert carbon monoxide and water vapor into hydrogen and carbon dioxide, and reacts carbon monoxide and water vapor generated by gasification of biomass. Here, the pressure swing adsorption vessel is a device that purifies high purity hydrogen from mixed gas.

In one embodiment of the present application, a cooling device may be further included between the gas generating device and the water gas conversion reactor.

In one embodiment of the present application, the hydrogen double production device includes the upper cycle device including the thermochemical redox reactor; And it may include the bottom cycle device including the gas generating device, the water gas conversion reactor, and the pressure swing adsorption vessel. As an example herein, the top cycle device may include the thermochemical redox reactor, the thermal energy storage device, and/or the solid heat recovery device, or the thermochemical redox reactor, the thermal energy storage device and a solid heat recovery device. As an example of the present application, the bottom cycle device may be composed of the gas generating device, the water gas shift reactor, and the pressure swing adsorption vessel.

Hereinafter, the present application will be described in more detail using examples. However, the following examples are merely illustrative to aid understanding of the present application, and the content of the present application is not limited to the following examples.

[Example]

1. Main design of the hospital

h_solid(고체 열; solid heat)는 2,263 kJ/mol-H₂로 계산할 수 있다. 도 1에서 세리아의

h_rd (환원열; heat of reduction)는 466 kJ/mol-H₂이다. 수소의 고위 발열량 (higher heating value; HHV_H2)인 286 kJ/mol-H₂에 비해 가열 및 환원에 필요한 에너지의 양이 훨씬 더 많아 시스템의 효율이 낮으며, 열-화학적 효율(thermal-to-chemical efficiency; η_th)은 하기 식 (5)로부터 10.5%로 계산될 수 있다.Since the value of δ is generally small, a large amount of metal oxide is required to produce a unit amount of hydrogen. In the case of ceria, δ (oxygen vacancies) is 0.0221 under typical reducing conditions of 1500°C and 1 mbar of oxygen pressure, which means that about 45 moles of ceria must be used to produce 1 mole of hydrogen. do. On a mass basis, 3,894 g of ceria is required to produce 1 g of hydrogen. This has been considered the main cause of the low efficiency of this technology because a lot of energy must be supplied to the fourth step, the heating step in Figure 1. Assuming that oxidation proceeds at atmospheric pressure and 900°C, which are common ceria oxidation conditions, the amount of heat required to increase the temperature of ceria from the oxidation temperature to the reduction temperature, in Figure 1

h _solid (solid heat) can be calculated as 2,263 kJ/mol-H ₂ . In Figure 1, the ceria

h _rd (heat of reduction) is 466 kJ/mol-H ₂ . Compared to the higher heating value (HHV _H2 ) of hydrogen, which is 286 kJ/mol-H ₂ , the amount of energy required for heating and reduction is much higher, so the efficiency of the system is low, and the thermal-to-chemical efficiency (thermal-to-chemical efficiency) is low. Chemical efficiency; η _th ) can be calculated as 10.5% from equation (5) below.

h_solid의 크기가 더 커지는 것을 의미한다. 상기 다른 재료의 열용량 (heat capacity)이 세리아의 열용량과 같을 때

h_solid는 4,526 kJ/mol-H₂가 되고 효율은 5.7%가 된다.This is the ideal case where all material in the reactor consists of ceria. In fact, because there are other materials such as alumina for insulation or alloys for the reactor shell, these other materials are inevitably heated and cooled during the thermochemical redox cycle, which causes

This means that the size of h _solid becomes larger. When the heat capacity of the other materials is equal to that of ceria

h _solid becomes 4,526 kJ/mol-H ₂ and the efficiency becomes 5.7%.

To solve these problems, much research has been conducted to develop new reactor designs that enable solid heat recovery. Various reactor designs have been proposed, generally seeking to recover the large solid heat lost during the temperature reduction phase and utilize this solid heat in the temperature increase phase. However, in the present invention, it was simply assumed that the reactor could have good solid heat recovery efficiency, and solid heat recovery sufficient to achieve high efficiency was analyzed.

Accordingly, Figure 2 shows the solid heat recovery efficiency, the efficiency of the solid heat recovery type reactor according to ε _solid . The thermo-chemical efficiency can be calculated as the following equation (6):

As shown in Figure 2, as solid heat recovery efficiency increases, thermo-chemical efficiency increases. However, even with a good solid heat recovery efficiency of, say, 0.7, the system efficiency is still close to about 15%, which means that more than 80% of the input energy is lost. More importantly, the energy is high-quality heat, since the minimum temperature of the system is still very high, 800 to 900° C. for ceria.

In order to utilize the high-quality waste heat and increase hydrogen production, the present invention proposes the idea of adding a bottom cycle process to the thermochemical redox cycle process, and Figure 3 shows a schematic diagram of the idea. In theory, any endothermic process operating near the oxidation temperature can be used as a bottom cycle. For example, representative bottom cycles are power generation cycles such as the Rankine cycle or the supercritical CO ₂ Brayton cycle.

Another good aspect of this combination is that the top thermochemical redox cycle process produces oxygen and hydrogen, which pure oxygen can also be utilized as a feedstock for fuel production processes such as biomass gasification in the bottom cycle process. .

The bottom cycle process using biomass includes a water gas conversion process and a pressure swing adsorption process, so high-quality hydrogen can be extracted. In the following, the detailed design of the bottom cycle process is proposed and a simulation model is constructed to analyze the performance of the hydrogen dual production process.

2. Hydrogen dual generation device

Figure 4 shows a schematic diagram of the hydrogen dual production device proposed herein. The thermochemical redox upper cycle process receives heat from a heat source to generate hydrogen and oxygen from water, and waste heat is transferred from the upper cycle process to the lower cycle process.

The top cycle process consists of a thermochemical redox reactor, a solid-state heat recovery component and a gas conditioning component. As described above, the inventors achieve solid-state heat recovery through multiple thermochemical redox reactors and heat transfer between them. It was also assumed that ceria, the benchmark material for this technology, was used as the metal oxide. Here, the gas conditioning component recovers the heat contained in the exhaust gas of the thermochemical redox cycle process, and two heat exchangers are used for gas heat recovery. This part contains a vacuum pump to provide appropriate pressure conditions to the reduction reactor. Additionally, a water pump is used to supply water and a condenser is used to condense the water and extract hydrogen from the exhaust gas.

The bottom cycle process receives waste heat from the top cycle process. Biomass supplied externally, pure oxygen and high-temperature waste heat generated from the upper cycle process are transferred to the gas generating device in the lower cycle process, and gasification of biomass occurs. The high temperature gas of 800℃ generated in this way is moved to the cooler. Afterwards, the cooled gas is converted into water gas at a temperature of 350℃, and purified hydrogen is extracted through a pressure fluctuation adsorption process under 20 bar and 25℃ conditions.

The input parameters for system operation can be classified into three categories: reactor-related parameters, material-related parameters, and system-related parameters.

For the reactor, three parameters are considered: ε _solid , C _factor (heat capacity factor of reactor), and HL _factor (heat loss factor of reactor), and the definition of each parameter is is equivalent to the following equations (7) to (9):

For materials, the following five parameters are considered:

T _rd (reduction temperature);

δ _rd (oxygen vacancy after reduction);

c _p (heat capacity);

h_rd (금속 산화물의 환원 엔탈피); 및

h _rd (enthalpy of reduction of metal oxide); and

(반응에 사용되는 물의 과잉량,):

(excess amount of water used in the reaction,):

For the system, two parameters ε _HEX and η _isen are considered to analyze the performance of heat exchangers and turbomachinery in the overall system, where ε _HEX is the heat exchanger efficiency and η _isen is the isentropic efficiency.

3. Simulation

Each system component is modeled as a zero-dimensional simulation model, and the simulation models of the system components are integrated to form an overall system simulation model. MATLAB and Cantera thermodynamic tools were used to construct the simulation model.

3.1 Methodology

3.1.1 Simulation model of each component

Thermochemical redox reactor

The thermochemical redox reactor was modeled based on the thermodynamic data of ceria and the solid heat recovery effect. The thermochemical redox reactor receives heat from a heat source and performs an endothermic reduction reaction to convert CeO _2-δox into CeO _2-δrd and increase the temperature of the solid reactor. Therefore, the amount of heat required for the above two steps can be calculated as shown in Equations (11) to (13) below. The heat input from the heat source is calculated as equation (14) considering the heat loss from the reactor to the surroundings [q: heat (intensive), δ: oxygen vacancy, q _{solid, unrecup} ; solid heat without heat recovery, T: temperature, c _active : heat capacity of metal oxide, rd: reduction, ox: oxidation].

Here, the heat of reduction reaction (Δh _rd ), in the case of ceria, is a function of oxygen vacancy δ that can be calculated as in the following equation (15). The amount of oxygen deficiency according to temperature and pressure can be calculated using Equation 16 below, derived based on thermodynamic equilibrium data. Solid heat was calculated based on the solid heat recovery efficiency ε _solid , the heat capacity of ceria, which depends on temperature as shown in equation (17) below, and the coefficient C _factor , which takes into account the heat capacity of other inert materials such as insulation.

Meanwhile, the heat transferred from the upper cycle device to the lower cycle device is the sum of the enthalpy of the exothermic oxidation reaction and the heat remaining in the solid reactor after solid heat recovery. The amount of heat can be expressed as equations (18) and (19) below.

It was assumed that the temperatures of streams 11 and 8 in FIG. 1, which are the exhaust gases of the reactor, were the same as the temperatures of the reduction reaction and the oxidation reaction, respectively.

heat exchanger

The device has two heat exchangers (HEX-R, HEX-O). Each heat exchanger is modeled as a countercurrent heat exchanger, and the model uses the heat exchanger efficiency ε _HEX to calculate the amount of heat exchanged. The equations used in the heat exchanger simulation model are as follows:

pump

The pump was similarly modeled based on the isentropic efficiency, η _isen . The system has two pumps (water pump and vacuum pump). Among these, the energy consumption of water pumps was generally ignored because it is much smaller than that of gas-powered pumps. The equations used in the simulation model are as follows.

gas generator

The gas generation device was modeled to gasify biomass to produce synthesis gas mainly composed of carbon monoxide and hydrogen. It receives not only waste heat but also pure oxygen from the upper cycle device to proceed with the reaction of biomass and water vapor. Here, the amount of product can be calculated using equation (26) derived based on thermodynamic equilibrium data.

In this case, the gasification reaction equation (27) is as follows.

Since the gasification reaction takes place at a temperature of about 850°C, it was assumed that sufficient gasification of the gasification fuel could be achieved and that the amount of charcoal (C) generated after the reaction could be sufficiently ignored.

water gas shift reactor

The water gasification reaction is a reaction that converts carbon monoxide and water vapor into hydrogen and carbon dioxide. The chemical formula (28) used in the reactor simulation model is as follows.

It is supplied with carbon monoxide obtained from the gasification of biomass, and steam, and operates at 350°C.

Pressure swing absorption vessel

A pressure swing adsorption vessel was modeled to purify high purity hydrogen from mixed gas. Here, the amount of hydrogen circulation is calculated as shown in equation (29) below. is the molar flow rate of hydrogen, means the circulation ratio with a value of 90%.

Other elements (condenser and gas generator)

In the condenser of the upper cycle device, it was assumed that all vapors of the gas were condensed into water and that there was no energy consumption in the condenser. The gas generating unit of the lower cycle unit receives waste heat from the upper cycle unit.

3.1.2 Algorithm of system simulation

Figure 5 shows an algorithm for calculating steady-state system simulation results based on the simulation model of the above-described components and input parameters. The respective hydrogen production in the top and bottom cycle processes is calculated in the above algorithm.

3.2 Results

In Table 1 below, the input parameters were chosen to represent the typical operating conditions of the system. In the following, the system operation results are analyzed.

input parameters value reactor ε _solid 0.7 C _factor 2 HL _factor 0.1 matter
(material) T _rd 1500℃ δ _rd 0.0221 C _active c _ceria Δh _rd Δh _rd,ceria β 3 system _εHEX 0.85 η _isen 0.88

3.3 Bottom cycle process simulation results Table 2 shows the amount of hydrogen generated when biomass gasification of the bottom cycle process was performed using waste heat and pure oxygen transferred from the top cycle process. The reaction was carried out in a gasifier with water vapor using externally supplied biomass and a selective reduction catalyst. After that, the reaction was carried out in a series of cooling process, water gas conversion process, and pressure fluctuation adsorption process. As a result, when hydrogen was produced at a flow rate of 1 mol/s in the upper cycle process, it was produced at a flow rate of 14.617 mol/s in the lower cycle process. Hydrogen was produced at the flow rate.

Waste heat transferred from upper cycle processes
(Waste heat from topping cycle) 1.4312e ³ kW Steam-to-carbon ratio (SCR) 1.34 Biomass mole flow rate 9.16mol/s Hydrogen production (H ₂ production) 14.617 mol/s

The description of the present application described above is for illustrative purposes, and those skilled in the art will understand that the present application can be easily modified into other specific forms without changing its technical idea or essential features. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as single may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present application is indicated by the claims described below rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present application. .

Claims (13)

Top cycle process including thermochemical redox cycle; and
It includes a bottom cycle process using waste heat and pure oxygen generated in the top cycle,
The upper cycle process and the lower cycle process both produce hydrogen,
As a hydrogen double production process,
The top cycle is a thermochemical redox cycle process according to the oxidation-reduction reaction of metal oxide,
The bottom cycle process includes a biomass gasification process using the waste heat, a water gas conversion process, and a pressure swing adsorption process,
Hydrogen dual production process. delete delete According to claim 1,
The upper cycle process is a hydrogen dual production process that is driven based on a regenerative heat source. delete According to claim 1,
A dual hydrogen production process, further comprising a cooling process between the biomass gasification process and the water gas conversion process of the bottom cycle process. According to claim 1,
The upper cycle process further includes a thermal energy storage process for storing waste heat generated in the upper cycle process. an upper cycle unit driving a thermochemical redox cycle process; and
It includes a lower cycle device that uses waste heat and pure oxygen generated from the upper cycle device,
The upper cycle device and the lower cycle device both produce hydrogen,
A hydrogen double production device that drives the hydrogen double production process according to any one of claims 1, 4, 6, and 7. According to claim 8,
The upper cycle device includes a thermochemical redox reactor. According to claim 8,
A dual hydrogen generation device further comprising a thermal energy storage device for storing waste heat generated in the upper cycle device. According to claim 8,
Wherein the bottom cycle device includes a gas generating device that performs biomass gasification. According to claim 11,
The bottom cycle device further includes a water gas conversion reactor and a pressure swing adsorption vessel. According to claim 12,
A dual hydrogen generation device, further comprising a cooling device between the gas generation device and the water gas conversion reactor.