A combustion reaction module and its filling method and application

Abstract

The present invention discloses a combustion reaction module, comprising: a module shell, a module center column, a catalytic combustion catalyst, and a plurality of internal wire meshes; the module shell has an internal space, and the upper and lower parts of the module shell are provided with openings for allowing catalytic combustion fuel and air to enter the combustion reaction module or be discharged from the combustion reaction module; a combustion chamber is formed between the module center column and the module shell; the internal wire meshes are arranged in the combustion chamber, the center of each internal wire mesh is hollowed out for the module center column to pass through, and the plurality of internal wire meshes are distributed axially along the module shell; the catalytic combustion catalyst is filled in the combustion chamber and is separated by the plurality of internal wire meshes.

Description

Technical Field

[0001] The invention relates to a combustion reaction module and a filling method and application thereof. Background Art

[0002] Fuel cells are a very attractive technology, with high efficiency and no polluting emissions, making them a promising technology to be integrated into energy systems. Despite the many advantages of fuel cells, the hydrogen storage problem is often considered to be a bottleneck in realizing hydrogen energy systems. Currently, physical storage devices such as cryogenic liquid H2 tanks or highly compressed gas H2 tanks are the most mature technologies, with technical indicators close to the requirements of the US Department of Energy (5.5wt% and 40g / L of hydrogen storage capacity in 2020) and the European Union (5wt% and 22g / L of hydrogen storage capacity in 2020), but they also have some disadvantages: compressed hydrogen requires large-capacity tanks (depending on the pressure), and the higher the tank pressure, the thicker the tank wall, which leads to increased cost, weight and safety issues. Cryogenic liquid H2 is suitable for large-scale storage, but for portable and on-board applications, hydrogen evaporation losses and liquefaction process costs become important disadvantages. Therefore, due to the significant technical issues and volume limitations of cryogenic liquid hydrogen and compressed hydrogen systems, the use of fuel cells in portable electronic devices and vehicles requires further research on methods to store hydrogen.

[0003] Chemical storage of hydrogen is gaining increasing attention; various metal and complex hydrides are being investigated, but the thermodynamics and kinetics of hydrogen storage / release in these storage technologies currently allow sufficient capacity only under extreme conditions. Therefore, the use of liquid organic hydrogen carriers (LOHCs) seems to be the most mature technology in this field at present. After nearly a decade of continuous and intensive research, hydrogen storage systems based on LOHCs have emerged as a very promising technology for hydrogen storage and transportation. These systems consist of a pair of organic compounds: the dehydrogenated state is an unsaturated compound (usually aromatic or heteroaromatic), while the hydrogen-rich state is usually a cyclic or heterocyclic compound. Since most low carbon-to-hydrogen ratio compounds are liquids at ambient conditions and have physical properties similar to gasoline or diesel, they are relatively safe and easy to handle. The existing infrastructure established for the transportation and storage of fossil fuels can be easily compatible. The dehydrogenation and hydrogenation processes required for the H2 cycle using LOHCs are well known, and the catalysts have been optimized for many rounds. The existence of large-scale hydrogenation plants worldwide is another advantage for the integration of LOHCs in energy systems.

[0004] Despite the technical, environmental and economic advantages, the concept of hydrogen storage in liquid organic carriers has not been widely developed commercially, mainly due to the energy limitations required to extract hydrogen from hydrogen-rich organic liquids. The most commonly used heat source is electrical heating, but there will also be energy losses in the process of converting hydrogen into electrical energy, resulting in a very low energy efficiency of the final energy storage system. Therefore, the reaction heat of chemical reactions is a more ideal heat source.

[0005] CN112265961A discloses an online hydrogen supply system based on alcohol fuel reforming reaction, comprising a raw material box, a heat exchanger connected to the raw material box through a raw material metering pump, a hydrogen production-purification integrated reactor connected to the raw material box through a fuel metering pump, an air pump connected to the hydrogen production-purification integrated reactor, a cooler and a hydrogen storage tank connected to the cooler. The hydrogen production-purification integrated reactor comprises a vaporization chamber, a reforming reaction chamber, a catalytic combustion chamber, a hydrogen purification chamber, a temperature sensor and a reforming product gas conveying coil. The reforming reaction chamber, the catalytic combustion chamber and the hydrogen purification chamber are cylindrical sleeve structures and are arranged in sequence from outside to inside. The hydrogen supply system of the invention has the advantages of high hydrogen storage density, small volume and weight, wide raw material sources, wide application range, and hydrogen can be produced and used immediately.

[0006] CN112174089A discloses an organic liquid hydrogen supply system for a closed environment, comprising a material storage unit, a hydrolysis hydrogen production unit, an organic liquid dehydrogenation unit and a product processing unit. The hydrolysis hydrogen production unit uses metal hydrogen compounds and water as raw materials, and prepares a mixed gas of hydrogen and water vapor through hydrolysis. Oxygen and the mixed gas enter the organic liquid dehydrogenation unit to undergo a safe catalytic combustion reaction. The organic liquid undergoes a catalytic dehydrogenation reaction at a certain temperature, and the combustion tail gas water vapor is recycled after being cooled in the product processing unit. The system uses a mixed gas of hydrogen and water vapor as fuel. Water vapor, as an inert gas, can reduce the hydrogen-oxygen reaction rate and ensure the safety of the system. It has the advantages of no need for external heating, high hydrogen storage density, safety and reliability, and no by-product gas emission. It is suitable for closed environments such as underwater vehicles and deep-sea equipment.

[0007] CN104888664A discloses a self-heating hydrogen supply device and its application. The self-heating hydrogen supply device adopts a concentric sleeve structure, including an inner tube (A) and an outer tube (B); the inner tube is a catalytic dehydrogenation reactor, and the outer sleeve is a hydrogen catalytic combustion reactor; the inner tube is filled with an integral hierarchical structure nano-carbon fiber catalyst bed, and the outer wall of the inner tube is coated with a catalyst layer, the thickness of the catalyst coating is 0.15-2.5μm, and is used for hydrogen catalytic combustion reaction; the inner diameter of the outer tube of the sleeve is 1.2-2 times the outer diameter of the inner tube.

[0008] The above patents have achieved certain results in exploring the organic liquid hydrogen supply device. However, they all have the problem that the catalytic combustion reaction is too concentrated, resulting in excessively high local temperature of the reaction system and excessive temperature difference of the dehydrogenation bed. Summary of the invention

[0009] The present invention aims to solve the problems in the prior art that the organic liquid hydrogen supply device has too high energy consumption, the local temperature of the reaction system is too high, and the temperature difference of the dehydrogenation reaction bed is too large. The present invention provides a combustion reaction module and a filling method and application thereof. When the reaction module is used for releasing hydrogen from organic liquid, the energy consumption is low and the temperature distribution of the reaction system is uniform.

[0010] The objectives of the present invention are achieved through the following technical solutions.

[0011] In a first aspect, the present invention provides a combustion reaction module.

[0012] It includes: module shell, module center column, catalytic combustion catalyst, and multiple internal wire meshes; among which,

[0013] The module housing has an internal space, and the upper and lower parts of the module housing are provided with openings for allowing catalytic combustion fuel and air to enter the combustion reaction module or to be discharged from the combustion reaction module;

[0014] The module center column is arranged in the inner space of the module shell and coincides with the axis of the module shell, and a combustion chamber is formed between the module center column and the module shell;

[0015] The internal wire mesh is arranged in the combustion chamber, the center of each internal wire mesh is hollowed out for the module center column to pass through, and a plurality of the internal wire meshes are distributed along the axial direction of the module shell, and the plurality of the internal wire meshes preferably extend perpendicularly to the axial direction of the module shell;

[0016] The catalytic combustion catalyst is filled in the combustion chamber and is separated by a plurality of the internal wire meshes.

[0017] In some embodiments, the upper and lower openings of the module housing allow catalytic combustion fuel and air to enter the combustion reaction module from the upper opening and be discharged from the combustion reaction module from the lower opening; in other embodiments, the catalytic combustion fuel and air are allowed to enter the combustion reaction module from the lower opening and be discharged from the combustion reaction module from the upper opening. Preferably, the upper and lower openings of the module housing are located at the top and bottom of the module housing.

[0018] In some embodiments, the catalytic combustion catalyst includes component a and component b, wherein component a is 0.01-5 parts by weight of an alloy of one or more elements selected from Group VIII of the periodic table, preferably Pt, Pd, Rh or Ir.

[0019] In some embodiments, the component b is 98 to 99.99 parts by weight of a carrier, preferably one or more of alumina or silicate ceramics.

[0020] According to the combustion reaction module of the present invention, the internal wire mesh divides the catalyst loaded in the combustion chamber into n equal sections, and each section of the catalytic combustion catalyst loaded is divided by two adjacent internal wire meshes, and the internal wire meshes are distributed along the axial direction of the module shell at intervals of l.

[0021]

[0022] Wherein, L is the total length of the catalyst layer along the axial direction, n is an integer between 3 and 10, z is the component content multiple, which is between 0.1 and 1, c is the content of component a contained in the catalytic combustion catalyst loaded in each section, C is the maximum content of component a contained in the catalyst and is between 0.01 and 0.05, and k is a natural constant between 5 and 60.

[0023] In some embodiments, the difference between the outer diameter and the inner diameter of the combustion chamber cross section is 20-60 mm.

[0024] In some embodiments, the module housing is cylindrical with an aspect ratio of 2.5-15.

[0025] In some embodiments, the intervals between adjacent internal wire meshes are 5-30 mm, and the internal wire meshes are unevenly distributed along the axial direction.

[0026] In some embodiments, the inner mesh has a plurality of openings with a pore size of 2-5 mm.

[0027] In some embodiments, the catalytic combustion catalyst occupies 0.8 to 1 of the total volume of the combustion chamber.

[0028] According to the combustion reaction module of the present invention, it also includes a packing layer shell, including two pieces, which are located inside the module shell and distributed at both ends of the module shell respectively. The catalytic combustion catalyst is loaded inside the module shell and between the two packing layer shells.

[0029] In some embodiments, the inner screen material is the same as the outer shell material of the packing layer.

[0030] In some embodiments, the internal wire mesh material is one of copper alloy, aluminum alloy, and stainless steel.

[0031] In a second aspect, the present invention provides a method for filling the above-mentioned combustion reaction module, comprising: filling a catalytic combustion catalyst into a combustion chamber to obtain the above-mentioned combustion reaction module.

[0032] In a third aspect, the present invention provides applications of the above-mentioned combustion reaction module.

[0033] In some embodiments, the combustion reaction module provided by the present invention is used in hydrogen storage.

[0034] In some embodiments, the hydrogen-releasing tubular reactor is housed within a column in a module.

[0035] In some embodiments, an insulation layer is wrapped around the outer shell of the combustion reaction module.

[0036] In some embodiments, the inner diameter of the column in the combustion reaction module is the same as the outer diameter of the hydrogen-releasing tubular reactor, and the inner wall of the column in the module fits with the outer wall of the hydrogen-releasing tubular reactor.

[0037] In some embodiments, a dehydrogenation catalyst is loaded inside the hydrogen-releasing tubular reactor; a catalytic combustion reaction is carried out in the catalytic combustion reactor, and a dehydrogenation reaction of the hydrogen-rich organic liquid is carried out in the dehydrogenation reaction tube.

[0038] In some embodiments of the present invention, the hydrogen-rich organic liquid is selected from one or more of cyclohexane, methylcyclohexane, tetralin, decalin, perhydroethylcarbazole, perhydrophenanthrene, perhydroanthracene, perhydrocarbazole or their derivatives, components cut from petroleum or petroleum fractions, and materials after hydrogenation of the cut components.

[0039] In some embodiments, the maximum axial temperature difference in the combustion reaction module is 20-100°C.

[0040] In some embodiments, the maximum axial temperature difference in the hydrogen-releasing tubular reactor is 10-30°C.

[0041] In a fourth aspect, the present invention provides a dehydrogenation catalyst, comprising, by weight: 0.1 to 5 parts of an alloy of one or more elements selected from Group VIII of the periodic table, and 75 to 99 parts of a carrier.

[0042] In some embodiments, the Group VIII element is Pt, Pd, Rh or Ir.

[0043] In some embodiments, the support is a carbon support, and the carbon support is a carbon nanotube, graphene, or graphyne.

[0044] In some embodiments, the carbon support is treated with a halogen.

[0045] Compared with the prior art, the present invention has the following beneficial effects:

[0046] The combustion reaction module provided by the present invention is an integral catalytic combustion reaction module, which has a multi-layer wire mesh structure inside, catalysts are filled between the wire meshes, and the internal wire meshes are distributed at intervals of l along the axial direction of the module shell, l=L / n / z / k, z=c / C. That is, the present invention obtains the internal wire mesh distribution interval along the axial direction of the module shell at one time through a special design by using the catalyst layer according to the total length L, the component content multiple z, the content c of component a contained in each section of the catalytic combustion catalyst filled, and the maximum value C of the content of component a contained in the catalyst. The maximum axial temperature difference in the catalytic combustion chamber of the organic liquid hydrogen release reactor is effectively controlled to be 100°C, and the maximum axial temperature difference in the dehydrogenation reaction chamber is 30°C, and the conversion rate of the dehydrogenation reaction of the hydrogen-rich organic liquid is above 90%.

[0047] Reference numerals

[0048] Figure 1 This is a schematic diagram of the structure of the internal wire mesh of the catalytic combustion reaction module of Example 1;

[0049] Figure 2 This is a schematic diagram of the structure of the catalytic combustion reaction module of Example 1.

[0050] 1-module housing; 2-module center column; 3-internal screen. DETAILED DESCRIPTION

[0051] In order to make the present invention easier to understand, the present invention will be described in detail below with reference to embodiments and drawings. These embodiments are only for illustration and are not intended to limit the application scope of the present invention.

[0052] Example 1

[0053] A basic embodiment of the present invention is Figure 1 and Figure 2 As shown, the combustion reaction module of this embodiment comprises a module shell 1 , a module center column 2 , a catalytic combustion catalyst, and four internal wire meshes 3 .

[0054] The module housing 1 has an internal space, and openings are provided at the top and bottom of the module housing 1. The top is used for catalytic combustion fuel and air to enter the combustion reaction module, and the bottom is used for exhaust gas after combustion to be discharged from the combustion reaction module. The module housing 1 is cylindrical, with a length of 156 mm and a diameter of 68 mm.

[0055] The module center column 2 is arranged in the inner space of the module housing 1 and coincides with the axis of the module housing 1, and a combustion chamber is formed between the module center column 2 and the module housing 1. The combustion chamber has an outer diameter of 60 mm and an inner diameter of 30 mm.

[0056] Three sections of internal screens 3 are arranged in the combustion chamber, each of which is hollowed out in the center for the module center column 2 to pass through, and is distributed axially along the module shell 1; the internal screen 3 has a plurality of openings with an aperture of 2-5 mm.

[0057] Take appropriate and equal amounts of catalytic combustion catalysts with Pt metal contents of 1%, 0.4% and 2% respectively, and load them into the integral catalytic combustion reaction module from bottom to top, so that the catalyst filling height is 90% of the height of the combustion reaction module. The intervals l1, l2, and l3 of the wire mesh inside the catalytic combustion reaction module in the catalysts with different active metal contents are 8 mm, 20 mm, and 4 mm respectively.

[0058] L is the height of the combustion bed 126 mm, n is the number of loading stages 3, C = 2%, and k is the natural constant 10.5.

[0059] c1=1%, then z1=0.5, l1=126 / (3*0.5*10.5)=8mm; c2=0.4%, then z2=0.2, l2=126 / (3*0.2*10.5)=20mm; c3=2%, then z3=1, l3=126 / (3*1*10.5)=4mm.

[0060] The catalytic combustion reaction module is sleeved on the hydrogen-rich organic liquid hydrogen-releasing tubular reactor filled with dehydrogenation catalyst, and the bottoms of the two are leveled, and a heat-insulating layer is added on the outer side of the integral catalytic combustion reaction module.

[0061] Appropriate amounts of benzene and cyclohexane were introduced into the integral catalytic combustion reaction module and the hydrogen-rich organic liquid hydrogen release tubular reactor for catalytic combustion reaction and dehydrogenation reaction, respectively. The reaction pressure was normal pressure, and the mass space velocity of the dehydrogenation reaction was 3.2 h -1 The dehydrogenation reaction temperature was guaranteed to be 300±50℃, and the maximum temperature of the catalytic combustion reaction bed was lower than 750℃. The maximum and minimum temperatures of each bed were measured by K-type thermocouples buried in the dehydrogenation reaction bed and the catalytic combustion bed. The dehydrogenation reaction conversion rate was measured by gas chromatography. The results are shown in Table 1.

[0062] Example 2

[0063] The combustion reaction module of this embodiment comprises a module shell, a module center column, a catalytic combustion catalyst, and five internal wire meshes.

[0064] The module housing has an internal space, and openings are provided at the top and bottom of the module housing, the top is used for catalytic combustion fuel and air to enter the combustion reaction module, and the bottom is used for exhaust gas after combustion to be discharged from the combustion reaction module. The module housing is cylindrical, with a length of 150 mm and a diameter of 72 mm.

[0065] The module center column is arranged in the inner space of the module shell and coincides with the axis of the module shell, and a combustion chamber is formed between the module center column and the module shell. The outer diameter of the combustion chamber is 64mm and the inner diameter is 32mm.

[0066] Four sections of internal wire mesh are arranged in the combustion chamber, each of which has a hollow center for the module center column to pass through, and is distributed axially along the module shell; the internal wire mesh has a plurality of openings with an aperture of 2-5 mm.

[0067] Take appropriate and equal amounts of catalytic combustion catalysts with Ir metal contents of 1%, 0.6%, 0.8% and 3.6% respectively, and load them into the integral catalytic combustion reaction module from bottom to top, so that the catalyst filling height is 85.7% of the height of the reaction module, and the intervals l1, l2, l3, l4 of the wire mesh inside the catalytic combustion reaction module in the catalysts with different active metal contents are 13.5 mm, 22.5 mm, 16.88 mm and 3.75 mm respectively.

[0068] L is the height of the combustion bed 126 mm, n is the number of loading stages 4, C = 3.6%, and k is the natural constant 8.

[0069] c1=1%, then z1=0.2778, l1=120mm / (4*0.278*8)=13.5mm; c2=0.6%, then z2=0.1667, l2=120mm / (4*0.1667*8)=22.5mm; c3=0.8%, then z3=0.222, l3=120mm / (4*0.222*8); c4=3.6%, then z4=1, l4=120mm / (4*1*8).

[0070] The catalytic combustion reaction module is sleeved on the hydrogen-rich organic liquid hydrogen-releasing tubular reactor filled with dehydrogenation catalyst, and the bottoms of the two are leveled, and a heat-insulating layer is added on the outer side of the integral catalytic combustion reaction module.

[0071] Appropriate amounts of benzene and cyclohexane were introduced into the integral catalytic combustion reaction module and the hydrogen-rich organic liquid hydrogen-releasing tubular reactor for catalytic combustion reaction and dehydrogenation reaction (reaction parameters were the same as in Example 1). The highest and lowest temperatures of the respective beds were measured by K-type thermocouples buried in the dehydrogenation reaction bed and the catalytic combustion bed. The dehydrogenation reaction conversion rate was measured by gas chromatography. The results are shown in Table 1.

[0072] Example 3

[0073] Other conditions were the same as those in Example 1, except that the Pt metal content of the catalytic combustion catalyst was changed to 2%, and the spacing of the wire mesh inside the catalytic combustion reaction module in the catalyst was changed to 12 mm.

[0074] Table 1

[0075] project Catalytic combustion bed temperature difference ℃ Dehydrogenation reaction bed temperature difference ℃ Dehydrogenation reaction conversion rate % Example 1 95.2 29.6 90.8 Example 2 83.5 27.3 92.2 Example 3 230.8 90.2 82.0

[0076] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this field, under the technical enlightenment provided by the present invention, as common knowledge in the field, other equivalent variations and improvements can also be made, which should also be regarded as the protection scope of the present invention.

Claims

1. A combustion reaction module, characterized in that: include: Module shell, module center column, catalytic combustion catalyst, multiple internal wire meshes; among them, The module housing has an internal space, and the upper and lower parts of the module housing are provided with openings for allowing catalytic combustion fuel and air to enter the combustion reaction module or to be discharged from the combustion reaction module; The module center column is arranged in the inner space of the module shell and coincides with the axis of the module shell, and a combustion chamber is formed between the module center column and the module shell; The internal wire mesh is arranged in the combustion chamber, the center of each internal wire mesh is hollowed out for the module center column to pass through, and a plurality of the internal wire meshes are distributed along the axial direction of the module shell, and the plurality of the internal wire meshes preferably extend perpendicularly to the axial direction of the module shell; The catalytic combustion catalyst is filled in the combustion chamber and is separated by a plurality of the internal wire meshes; The internal wire mesh divides the catalyst loaded in the combustion chamber into n equal sections, and each section of the catalytic combustion catalyst is divided by two adjacent internal wire meshes. The internal wire meshes are distributed along the axial direction of the module shell at intervals of l. Wherein, L is the total length of the catalyst layer along the axial direction, n is an integer between 3 and 10, z is the component content multiple, which is between 0.1 and 1, c is the content of component a contained in the catalytic combustion catalyst loaded in each section, C is the maximum content of component a contained in the catalyst and is between 0.01 and 0.05, and k is a natural constant between 5 and 60.

2. The combustion reaction module according to claim 1, characterized in that: The catalytic combustion catalyst comprises component a and component b, wherein component a is 0.01-2 parts by weight of an alloy of one or more elements selected from Group VIII of the periodic table, and component b is 98-99.99 parts by weight of a carrier.

3. The combustion reaction module according to claim 2, characterized in that: The component a is selected from Pt, Pd, Rh or Ir, and the component b is selected from one or more of alumina or silicate ceramics.

4. The combustion reaction module according to any one of claims 1 to 3, characterized in that: The difference between the outer diameter and the inner diameter of the combustion chamber cross section is 20-60 mm, and / or the module housing is cylindrical with an aspect ratio of 2.5-15.

5. The combustion reaction module according to any one of claims 1 to 3, characterized in that: The intervals between adjacent internal screens are 5-30 mm, and the internal screens are unevenly spaced along the axial direction; and / or the internal screen has a plurality of openings with an aperture of 2-5 mm.

6. The combustion reaction module according to any one of claims 1 to 3, characterized in that: The catalytic combustion catalyst occupies 0.8-1 of the total volume of the combustion chamber.

7. A method for filling a combustion reaction module, comprising: The catalytic combustion catalyst is loaded into the combustion chamber to obtain the combustion reaction module described in any one of claims 1-6.

8. Use of the combustion reaction module according to any one of claims 1 to 6 or the combustion reaction module obtained according to the filling method of claim 7 in hydrogen storage.

9. The use of the combustion reaction module according to claim 8, characterized in that: The hydrogen-releasing tubular reactor is mounted in the module center column, an insulating layer is wrapped outside the combustion reaction module shell, the inner diameter of the module center column is the same as the outer diameter of the hydrogen-releasing tubular reactor, the inner wall of the module center column fits the outer wall of the hydrogen-releasing tubular reactor, and a dehydrogenation catalyst is loaded inside the hydrogen-releasing tubular reactor; a catalytic combustion reaction is carried out in the catalytic combustion reactor, and a dehydrogenation reaction of a hydrogen-rich organic liquid is carried out in the dehydrogenation reaction tube.

10. The use of the combustion reaction module according to claim 9, characterized in that: The maximum axial temperature difference in the hydrogen-releasing tubular reactor is 10-30°C.

11. The use of the combustion reaction module according to any one of claims 8 to 10, characterized in that: The maximum temperature difference of the combustion reaction module is 20-100°C.

Images