TWI394709B - An apparatus and method for producing hydrogen-rich gas with high performance - Google Patents

Description

Device and method for efficiently generating hydrogen-rich gas

This creation is a device and method for the production of high-efficiency hydrogen-rich gas or syngas, especially the structural design of the reactor. By recycling the waste heat of high-temperature gas production and the configuration of the movable catalyst bed, it can be smaller. The chemical reaction is carried out under the reaction space, and the conversion rate of the fuel is effectively increased, thereby enabling high-performance hydrogen-rich gas or synthesis gas to be produced.

According to the current global production of energy, oil, coal and natural gas are still the mainstream of fuel use. However, since the two energy crises caused in the 1970s, energy problems have become increasingly serious and vulnerable to international political situations. Furthermore, according to statistics published by BP in 2009, the reserves of oil and natural gas are rapidly decreasing. The oil reserves can be used for about 42 years, natural gas for about 60 years, and coal for about 120 years. . Therefore, the search for alternative fuels and renewable energy is a top priority for current energy development.

Moreover, it is well known that burning various fossil fuels such as oil, natural gas and coal is one of the main ways for humans to obtain energy today. If all kinds of fossil fuels are completely or incompletely burned, various air pollutants and carbon dioxide will be produced. Air pollutants, but a large amount released into the atmosphere will have a greenhouse effect. Since gaseous pollutants and particulate pollutants can be transported to other regions via the flow of the atmosphere, air pollution is not only a regional impact, but also a global common problem. In recent years, due to the rise of environmental awareness, preventing the rise of the Earth's temperature and suppressing the greenhouse effect has become an important issue internationally. In order to formulate a legally binding protocol, the International signed the "Kyoto Protocol" in the "Third Assembly of States Parties (COP3)" in Kyoto in December 1997 to regulate 38 countries and the European Union to control anthropogenic greenhouse gases. Quantity to reduce the impact of the greenhouse effect on the global environment.

At present, it can be used as renewable energy and energy for reducing greenhouse effect, mainly including solar energy, wind energy, hydropower, ocean energy, geothermal energy and biomass energy. In addition to the above-mentioned renewable energy sources, there is also hydrogen energy with great potential for development in the future. The advantage of hydrogen is that it is clean, non-polluting, sustainable supply and high thermal energy. The main by-product of hydrogen is water vapor when it is used in combustion, so it is called green. energy. Furthermore, hydrogen can be stored and transported wherever it is needed, which is beyond the reach of solar, wind and hydropower. Industrial hydrogen production is mostly derived from the production of hydrogen-rich gas, such as syngas. In the past, hydrogen has been used in a large number of chemical processes, and its related manufacturing, storage, transportation and use guidelines have been fully constructed. Hydrogen can be safely used as long as the correct operating procedures and compliance with the specifications are followed.

The primary work of hydrogen energy development is the production of hydrogen-rich gas or pure hydrogen. There are many methods for producing hydrogen-rich gas or pure hydrogen, which can be mainly divided into: (1) thermochemical method; (2) electrochemical method; (3) Photoelectrochemical method; and (4) biophotoelectrochemical method. Although there are various techniques for producing hydrogen-rich gas or pure hydrogen, however, if hydrogen is produced by electrolysis, energy must be added to decompose water; biophotoelectrochemical method produces hydrogen at a slower rate and the source of the strain is not easily obtained: using semiconductor as a material. Although photoelectrochemical method is a hot research direction in recent years, its efficiency is low and there are still many technologies to be developed. Therefore, in the current practical application, the thermochemical method is still the mainstream of producing hydrogen-rich gas or pure hydrogen.

The main methods for the production of hydrogen-rich gas or synthesis gas by the aforementioned thermochemical method include steam reforming, partial oxidation, gasification, water gas shift and pyrolysis reaction. Etc., the produced hydrogen-rich gas can be synthesized by a Fischer-Tropsch process in addition to direct combustion or methanol synthesis in an internal combustion engine. Natural gas, petroleum, coal, petroleum coke, methanol, ethanol, and biomass can be used in the production of hydrogen-rich gas raw materials. At present, the most widely used method for producing hydrogen-rich gas or hydrogen is steam recombination, but it needs to provide a heat source by combustion or electrothermal to start the hydrogen production reaction; although the partial oxidation method can provide hydrogen-rich gas by self-heating or The heat required for hydrogen, but it also consumes part of the fuel, thus increasing manufacturing costs.

In view of the above problems, the inventors have developed "An apparatus and method for producing hydrogen-rich gas with high performance", which is a thermal cycle structure by Recycling waste heat from high-temperature gas production and heating low-temperature reactants, which will increase the reaction temperature of the reactants, thereby increasing chemical reaction efficiency, fuel conversion rate, and hydrogen-rich gas generation, thereby achieving high-efficiency hydrogen-rich gas. produce. In addition, since the reactor of the heat cycle structure makes full use of the space used for heat exchange, it can reduce environmental burden, space saving, fuel and the like while producing energy.

In order to achieve the technical object of the above object, "a device capable of generating a hydrogen-rich gas with high efficiency" is provided, which comprises a reactant control unit, a feed channel, a central catalyst bed, a gas flow path, and a heat exchange. a wall and a plurality of movable catalyst beds, wherein the feed flow path and the gas flow path are separated by a heat exchange wall, and the heat exchange wall can transfer waste heat of high temperature gas production in the gas flow path to the feed flow path The low temperature reactants thus achieve the effect of preheating the reactants, thereby achieving a high conversion efficiency in the fuel reaction process and increasing the concentration of syngas or hydrogen in the gas production.

For the method of the device of the present invention, please refer to the thermal cycle structure reaction device shown in FIG. 1 as a preferred embodiment structure, which can recover the waste heat of gas production and preheat the reactants, thereby improving the efficiency of hydrogen production, and the high efficiency can generate rich The hydrogen gas reaction device (1) comprises: a reactant control unit (10) having a fuel storage tank (11) and an oxidant storage tank (12), and a flow meter (13) outside the storage tank for individually controlling the fuel and the oxidant The flow entering the reaction device (1), the fuel and the oxidant can be mixed by the conduit (14) to the mixing tank (15), and then flow into the reaction device (1); wherein the fuel is methane, methanol or ethanol, and the oxidant is oxygen. Or water, and when the fuel is methane and the oxidant is oxygen, the volume flow ratio of methane to oxygen is 1:0.6~1:1.4; when the fuel is methanol and the oxidant is water, the volumetric flow ratio of methanol to water is 2:1~1:5; when the fuel is B When the alcohol and the oxidant are water, the volume flow ratio of ethanol to water is 1:1~1:10; when the fuel is methane and the oxidant is water, the volume flow ratio of methane to water is 1:1~1:10 .

a feed flow path (20), which is a single flow path structure, has a feed flow path inlet (21) for allowing fuel and oxidant to enter the reaction unit (1), and the top and bottom of the feed flow path (20) are Insulation layer, covered with thermal insulation material, the material can be insulated brick to avoid gas heat loss from above and below the reactor; a central catalyst bed (30), the central catalyst bed is filled with catalyst (31), catalyst It may be in the form of granules or powder to promote the reaction of hydrogen-rich gas such as partial oxidation reaction or steam recombination. The outer edge of the catalyst bed is provided with a heater (32), and the heater (32) may be an electric heating rod, which may be based on The chemical reaction needs to be heated, and the catalyst bed is provided with a heat sensor (33), the heat sensor (33) can be a thermocouple, and the reaction temperature can be monitored; and the gas flow channel (40) is a single stream. The channel structure has a water mist discharge port (41) at the outlet of the central catalyst bed, and the sprayed water mist can absorb the heat of the high temperature gas to form steam to serve as a subsequent enhanced hydrogen production reaction, and the end of the gas flow path (40) For the gas flow path outlet (42), the gas stream is discharged outside the reaction device, and the outermost layer of the reaction device is an insulated outer wall (43). The heat insulating outer wall (43) and the top and bottom of the gas flow path (40) are provided with a heat insulating material, which can be insulated brick to avoid heat loss of the gas; a heat exchange wall (50), the heat exchange The wall (50) may be made of a metal material, and the feed flow path (20) and the gas flow path (40) are separated, and the heat exchange wall (50) transfers heat of the high temperature gas to the low temperature reactant. Preheating the reactants and promoting the reaction of the reactants in the central catalyst bed (30); a plurality of movable catalyst beds (60), and the movable catalyst bed (60) is filled with a catalyst (61) The catalyst can be granular or powdery, and can carry out high temperature and low temperature water vapor transfer reaction to reduce the concentration of carbon monoxide in the hydrogen rich gas and increase the hydrogen concentration. The outer edge of the catalyst bed has a fixed net (62) to fix the catalyst. The bed, to avoid the escape of the catalyst, the number and position of the catalyst bed will be adjusted according to the actual chemical reaction requirements, in order to carry out the reaction of the optimized hydrogen-rich gas.

The technical content of the method of the present invention, please refer to the reference to see Figure 2, to generate hydrogen-rich The fuel and oxidant required for the body are respectively discharged from the fuel storage tank (11) and the oxidant storage tank (12), and the flow rate is controlled by the flow meter (13), and then flows through the conduit (14) to the inlet of the feed channel (21). ) and then into the feed flow path (20). As the reactants flow through the feed channel (20), they are preheated by the heat introduced in the gas stream (40) and then flow into the central catalyst bed (30). The heater (32) in the central catalyst bed (30) will be switched according to an endothermic or exothermic chemical reaction. If a catalytic partial oxidation reaction is carried out to generate a hydrogen-rich gas, it is an exothermic reaction, and the heater (32) is in the initial stage of the reaction. When the temperature of the central catalyst bed is high to a certain value, the heater (32) will be in a closed state; if the hydrogen-rich gas reacts to steam recombination, which is an endothermic reaction, the heater (32) will remain open. status. The thermal sensor (33) in the central catalyst bed (30) not only measures the reaction temperature, but also the measured temperature can be used as a reference for the operation of the heater (32). The reactant will generate a hydrogen-rich gas under the action of the catalyst (31), and the high-temperature hydrogen-rich gas will flow into the gas flow path (40) after leaving the central catalyst bed (30), and then transfer the heat to the feed flow path (20). ) to preheat the reactants. If hydrogen and carbon monoxide (ie, syngas) are the main products required for the reaction, the hydrogen-rich gas will flow directly to the gas stream outlet (42), and then the gas detection instrument will be used for the analysis of the outlet gas composition. If hydrogen is the main product required for the reaction and the concentration of carbon monoxide needs to be low, after the gas leaves the central catalyst bed (30), it will mix with the water mist sprayed from the water mist discharge port (41), water mist and high temperature. After the gas is combined, it will be evaporated into steam. After the mixed gas and steam flow through the movable catalyst bed (60), the water vapor transfer reaction can be carried out to convert carbon monoxide into carbon dioxide, and the steam is converted into hydrogen gas, thereby enhancing The concentration of hydrogen in the gas produced. If the temperature of the gas leaving the central catalyst bed (30) is extremely high, two or more movable catalyst beds (60) can be connected in series to perform a high-temperature and low-temperature water-gas transfer cascade reaction. After leaving the movable catalyst bed (60), the hydrogen-rich gas will flow to the gas flow path outlet (42), and then the gas detection instrument will be used for the analysis of the outlet gas composition.

The invention is further understood by the following examples, which are intended to be illustrative only and not to limit the scope of the invention.

Example 1

In the first embodiment, a catalytic partial oxidation reaction is carried out by the present invention, which is a high-efficiency reaction device for generating a hydrogen-rich gas, by catalytic partial oxidation of methane with oxygen in the air to produce a hydrogen-rich gas. In terms of the configuration of the catalyst bed, there is only a central catalyst bed, and there is no movable catalyst bed, and the water mist discharge port is closed, and the detailed configuration pattern is as shown in FIG. In terms of operating parameters, the volumetric flow rate of methane and oxygen in the reaction tube is set to 1:1 (C/O = 1), and the inlet temperature of the reactants entering the reactor is 300 K, and its residence time in the central catalyst bed It depends on the inlet flow. The catalyst used in the catalytic partial oxidation reaction is a ruthenium catalyst having a composition of 95% by weight of alumina and 5% of ruthenium metal. The catalyst surface is a porous structure that is active and will promote the occurrence of a catalytic partial oxidation reaction as it passes through the active surface.

Referring to FIG. 4, under the above operating conditions, and the gas hourly space velocity is controlled between 10,000 and 100,000 h ^-1 , that is, the total gas flow rate is different, and the present thermal cycle device is used. The conversion rate of methane catalyzing partial oxidation reaction under operation. As seen in Figure 4, the present authoring apparatus clearly has the effect of increasing the methane conversion rate compared to the reactor which is generally free of heat exchange. For example, when the gas hourly space velocity is 10,000 h ^-1 , the methane conversion rate under the operation of the present heat cycle device is 93%, which is much higher than 77% of the no heat exchange. Figure 5 shows the maximum temperature in the reactor. Similarly, when the reactor is heat-recovered, the maximum internal temperature can be higher than about 300K without heat exchange. In terms of catalytic partial oxidation, the higher the temperature, the better. Methane conversion rate. In general, the higher the hydrogen selectivity in the gas production, the higher the hydrogen concentration in the hydrogen-rich gas produced. Because of the curve distribution in Figure 6, it can be clearly seen that the hydrogen selectivity rate of the present thermocycling unit is much higher than that of no heat. The device for exchange, so the creation of the thermal cycle device does have the effect of significantly increasing the concentration of hydrogen in the gas.

Example 2

In the second embodiment, two movable catalyst beds are further added to the creation device, and the two catalyst beds are filled with a low-temperature water-gas shift reaction catalyst, and the composition thereof is copper oxide. (40-44%), zinc oxide (44-50%) and alumina (7-13%), the configuration of two mobile catalyst beds is shown in Figure 7. In order to carry out the water-gas shift reaction to further reduce the concentration of carbon monoxide in the gas production and increase the concentration of hydrogen, the water mist outlet of the outlet of the central catalyst bed is opened, and a sufficient amount of steam is sprayed, the steam temperature is 400K, and the steam is in contact with the center. The carbon monoxide concentration ratio of the outlet of the media bed is controlled to be 8.

Referring to FIG. 8, which is based on the operating conditions in Example 1, the gas hourly space velocity is 10,000 h ^-1 , and combined with the aforementioned steam operating parameters, the resulting gas production comparison result. If only the catalytic partial oxidation reaction, the concentration of hydrogen and carbon monoxide in the dry hydrogen-rich gas is 37.6 and 19.5% (that is, the synthesis gas concentration is 57.1%), the oxygen is completely reacted, the methane is only 2%, and the carbon dioxide concentration is 0.2. %. If the catalytic partial oxidation reaction is combined with the low-temperature water-gas shift reaction, the hydrogen concentration is greatly increased to 47.2%, the carbon monoxide concentration is 0%, the methane concentration is 1.9%, and the carbon dioxide concentration is increased to 16.3%. The above results show that under the action of the authoring device, the catalytic partial oxidation reaction and the water-gas transfer reaction can be successfully combined to convert hydrocarbons and steam into high-concentration hydrogen.

In summary, the present invention "a device and a method for efficiently generating hydrogen-rich gas" utilizes a heat-cycling device designed and erected by itself to recover heat energy to preheat the reactants, thereby not only performing high-performance catalytic partial oxidation reaction. In order to convert the fuel into a hydrogen-rich gas or a syngas, it is also possible to combine the water-gas shift reaction, and by reacting carbon monoxide with steam, the concentration of hydrogen in the gas can be further increased. Therefore, the present apparatus has multiple uses, which can be various depending on the industry. It is required to operate the device under different conditions to generate hydrogen-rich gas and syngas, and at the same time has the advantage of saving reactor space, that is, the method of the present invention utilizes the high-level creation of the natural law technical idea, conforms to the invention patent requirements, and is legally in accordance with the law. The application is filed.

(1) ‧‧‧Reaction device

(10) ‧‧‧Reaction Control Unit

(11) ‧‧‧fuel storage tank

(12) ‧‧‧Oxidant storage tank

(13)‧‧‧ Flowmeter

(14) ‧‧‧ catheter

(15)‧‧‧ mixing tank

(20)‧‧‧Feed runners

(21)‧‧‧Feed runner inlet

(30)‧‧‧Central Catalyst Bed

(31) ‧‧‧ Catalyst

(32)‧‧‧ heater

(33) ‧‧‧Thermal sensor

(40) ‧‧‧ gas flow

(41)‧‧‧Water spray outlet

(42) ‧‧‧air flow exit

(43) ‧ ‧ insulated exterior wall

(50) ‧ ‧ heat exchange wall

(60)‧‧‧Removable Catalyst Bed

(61) ‧‧‧ Catalyst

(62) ‧‧‧Fixed network

BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view (representative drawing) of a device for efficiently generating hydrogen-rich gas according to the present invention.

2 is a flow chart showing the manufacture of a hydrogen-rich gas in the process of the present invention.

Figure 3 is a configuration diagram of a device for performing a catalytic partial oxidation reaction of the apparatus of the present invention.

Fig. 4 is a graph showing the comparison of the methane conversion rate with the gas hourly space velocity after the partial oxidation reaction is subjected to heat exchange and non-heat exchange in the process of the present invention.

Fig. 5 is a graph showing the comparison of the maximum temperature of the reaction with the gas hourly space velocity after the partial oxidation reaction of the partial oxidation reaction is carried out by heat exchange and non-heat exchange.

Fig. 6 is a graph showing the comparison of the hydrogen selectivity with the gas hourly space velocity after the partial oxidation reaction is subjected to heat exchange and non-heat exchange in the method of the present invention.

Figure 7 is a configuration diagram of a device for performing catalytic partial oxidation combined with water vapor transfer reaction in the apparatus of the present invention.

Figure 8 is a graph showing the concentration values of the components of the dry gas in the gas production after the partial oxidation reaction combined with the water gas transfer reaction and the unbound water gas transfer reaction are carried out by the method of the present invention.

(1). . . Reaction device

(10). . . Reactant control unit

(11). . . Fuel storage tank

(12). . . Oxidizer storage tank

(13). . . Flow meter

(14). . . catheter

(15). . . Mixing tank

(20). . . Feed channel

(twenty one). . . Feed runner inlet

(30). . . Central catalytic bed

(31). . . catalyst

(32). . . Heater

(33). . . Thermal sensor

(40). . . Air flow

(41). . . Water spray outlet

(42). . . Gas flow exit

(43). . . Thermal insulation

(50). . . Heat exchange wall

(60). . . Movable catalyst bed

(61). . . catalyst

(62). . . Fixed network

Claims (17)

A high-efficiency apparatus for generating a hydrogen-rich gas, comprising: a reactant control unit, a feed flow path, a central catalyst bed, a gas flow path, and a heat exchange wall, wherein one end of the feed flow path The reactant control unit is connected, the other end of the feed flow channel is connected to one end of the central catalyst bed; the other end of the central catalyst bed is connected to the gas flow path; and the heat exchange wall is interposed between the feed flow channels Between the gas flow path and the gas flow path, the feed flow path and the gas flow path are separated from each other. The apparatus as recited in claim 1, wherein the reactant control unit has a fuel storage tank and an oxidant storage tank, and the fuel storage tank and the oxidant storage tank are respectively connected to a flow meter, and each flow meter system Connected to a conduit, each conduit is connected to a mixing tank so that the reactants can be mixed in the mixing tank and fed into the feed channel of the reaction unit. The apparatus as recited in claim 1, wherein the feed flow path is a single flow path structure having an inlet connected to the reactant control unit and allowing the reactant to be introduced into the reaction apparatus. The top and bottom of the flow channel are insulated to prevent gas heat from escaping from above and below the reactor. The apparatus as recited in claim 1, wherein the central catalyst bed has a catalyst, a heater and a heat sensor, and the catalyst can promote partial oxidation or steam recombination reaction to generate hydrogen-rich gas. It is located at the outer edge of the catalyst and can be heated according to the chemical reaction requirements. The thermal sensor is coated in the catalyst and can monitor the reaction temperature as a reference for the operation of the heater. The device as recited in claim 1, wherein the gas flow path is a single flow channel structure, one end of the gas flow path and a water mist discharge port at the junction of the gas flow path and the central catalyst bed, the water mist The spray outlet can spray water mist and absorb heat to form steam and carry out water-gas transfer reaction. The other end of the gas flow passage has a gas flow passage outlet, and the top, bottom and outermost layers of the gas flow passage are an insulated outer wall, and the heat insulation outer wall The wall can avoid heat loss from high temperature gas production. The apparatus as recited in claim 1, wherein the heat exchange wall partitions the feed flow path and the gas flow path, and performs heat exchange to preheat the reactants and promote reaction of the reactants in the central catalyst bed. The device as recited in claim 1, further comprising at least one movable catalyst bed, the at least one movable catalyst bed being disposed in the gas flow path and interposed between the central catalyst bed and the gas stream Between the exits of the passage, and the at least one movable catalyst bed has a catalyst and a fixed net for fixing the catalyst. A method for efficiently producing a hydrogen-rich gas, comprising: (a) mixing a fuel and an oxidant at a fixed flow rate into a mixing tank, and then feeding to a feed channel inlet, and then entering the reaction device; (b) The fuel and the oxidant are preheated in the feed channel through the heat exchange wall and then into the central catalyst bed; (c) the heater is turned on or off depending on the reaction state and the nature of the heat release; (d) the reactant is passed The central catalyst bed reacts to rapidly generate hydrogen-rich gas; (e) after the high-temperature gas leaves the central catalyst bed, it transfers heat to the feed channel in the gas flow path to preheat the reactants; (f) if it is necessary to increase the concentration of hydrogen in the gas and reduce the concentration of carbon monoxide, start the water mist and arrange at least one mobile catalyst bed; (g) further carry out the water-gas transfer reaction of the hydrogen-rich gas; (h) produce the gas stream The gas flow path exits and performs gas composition analysis. The method of claim 8, wherein the fuel of step (a) may be methane, and the oxidant may be oxygen or air for catalytic partial oxidation of methane. The method of claim 8, wherein the fuel of step (a) may be methanol and the oxidant may be water for methanol steam recombination reaction. The method of claim 8, wherein the fuel of step (a) is ethanol and the oxidant is water for ethanol steam reforming. The method of claim 8, wherein the fuel of step (a) may be methane and the oxidant may be water for methane vapor recombination reaction. The method of claim 8, wherein the heat exchange wall of step (b) is made of a metal material. The method of claim 9, wherein the volumetric flow rate ratio of methane to oxygen is 1:0.6 to 1:1.4. The method of claim 10, wherein the volumetric flow rate ratio of methanol to water is from 2:1 to 1:5. The method of claim 11, wherein the volumetric flow rate ratio of ethanol to water is 1:1 to 1:10. The method of claim 12, wherein the volumetric flow rate ratio of methane to water is 1:1 to 1:10.