CN103165924B - There is fuel rail and the application of fuel gas reformation and tail gas catalyzed combustion function - Google Patents

Abstract

The present invention relates to a kind of for anode-supported cast Solid Oxide Fuel Cell, there is catalytic fuel gas reform and the fuel rail and preparation method thereof of tail gas catalyzed combustion function.This fuel rail comprises the inertia stay pipe of a both ends open, and its inner and outer wall is all supported with catalyst layer, and thickness is 5-300 micron, and the composition of parietal layer catalyst is by weight percentage: Al ₂o ₃20% ~ 70%, CeO ₂10% ~ 40%, ZrO ₂0% ~ 40%, La ₂o ₃0-20%, containing at least one alkali metal or alkali earth metal oxide 0.5% ~ 10%, containing at least one 0.01 ~ 5.0% of platinum metal element as ruthenium, rhodium, palladium, osmium, iridium, platinum etc., containing period 4 VI in the periodic table of elements? I? the at least one 0.5-15% of I race element.The entrance point of this fuel rail connects common fuel chamber, outlet passes into anode-supported inertia galvanic anode chamber, its inner wall layer catalyst and be in outer wall layer catalyst in galvanic anode chamber can catalyzed aqueous vapour reforming natural gas, liquefied petroleum gas etc., produce reformed gas, the generating of supply anode-supported cast Solid Oxide Fuel Cell; The outer wall layer catalyst being in outside batteries can catalytic fuel tail gas and air generation combustion reaction, provides heat energy to reforming reaction and the gas that flows to battery.

Description

Fuel distribution pipe with fuel gas reforming and tail gas catalytic combustion functions and its application

technical field

The invention relates to a fuel distribution pipe with functions of fuel gas reforming and tail gas catalytic combustion and its application. The fuel distribution pipe can be applied to an anode support tubular solid oxide fuel cell power generation system with one end closed. It is used in distributing fuel At the same time, it catalyzes the reforming of fuel gas, catalyzes the combustion of exhaust gas at the outlet of the fuel cell, and simultaneously realizes the thermal coupling of reforming reaction, combustion reaction, and battery reaction, and improves the power generation efficiency and total energy utilization efficiency of the system.

Background technique

A solid oxide fuel cell (SOFC) is a power generation device that uses solid oxide as an electrolyte diaphragm to efficiently and cleanly convert the chemical energy of the fuel into electrical energy through an electrochemical reaction. Its power generation efficiency can reach more than 50%. The power supply efficiency is higher than 80%, and it is a new type of power generation device that reduces carbon dioxide emissions. Solid oxide fuel cells can not only use hydrogen fuel, but also use abundant and cheap natural gas, liquefied petroleum gas, fuel oil, city gas and biomass gas as fuel.

According to the different configurations of the core components of solid oxide fuel cells - membrane electrodes or single cells, solid oxide fuel cells can be divided into tubular cells, planar cells and monolithic cells. According to different supports of membrane electrodes or batteries, solid oxide fuel cells can be divided into electrolyte-supported, cathode-supported and anode-supported types. Different battery configurations and types of batteries use different component structures and construction methods in building battery stacks and power station systems, and the structures of battery stacks and power stations are also different. Among various types of batteries, the technology developed by Siemens-Westinghouse's cathode-supported tubular solid oxide fuel cell technology and the electrolyte-supported battery technology are relatively mature, and the working temperature of both batteries is above 900C. The anode-supported battery technology is a battery technology that has been developed at home and abroad in recent years, and the working temperature of the battery is 650-800C.

As mentioned above, natural gas and the like are fuels for solid oxide fuel cells, and solid oxide fuel cells can improve the utilization efficiency of natural gas. However, directly passing natural gas to the solid oxide fuel cell anode reaction will cause carbon deposition on the anode, which will destroy the current conduction interface, reduce the performance of the electrocatalyst, affect the gas mass transfer in the electrode, and reduce the battery life. Therefore, in the power generation system, fuels such as natural gas are generally reformed into synthesis gas through catalytic reforming of water vapor, and then electrochemically reacted on the anode of the battery.

The fuel reforming reaction is a strong endothermic reaction at high temperature (600-900°C): CH ₄ +H ₂ O→3H ₂ +CO, ΔH ₁₀₇₃ =225.7kJmol ^-1 , the reaction needs to provide a lot of heat energy . When the battery is working, some heat is generated because the voltage efficiency and current efficiency are not 100%; the catalytic combustion of fuel tail gas is a strong thermal reaction: H ₂ +0.5O ₂ →H ₂ O, ΔH ₁₀₇₃ =-248.3kJmol ^-1 , the battery stack The heat generated by the catalytic combustion of exhaust gas and tail gas needs to be removed in time to prevent local high temperature shocks. For strong endothermic reactions, how to promote heat transfer is an important factor to be considered in catalyst and reactor design.

The steam reforming reaction of natural gas and other fuels is carried out in a reforming reactor or on a reforming catalyst. The reforming reactor and reforming catalyst can be placed at any position where the fuel gas flows from the inlet of the fuel gas of the power generation system to the anode of the solid oxide fuel cell. Depending on the battery configuration and type, the location of the steam catalytic reforming reaction of natural gas is different. The reforming reactor is placed outside the battery stack, or the reforming catalyst is placed on the common flow cavity and flow channel outside the battery stack, which is called external reforming. For example, in the cathode support tubular battery power generation system described in U.S. Patent US007320836 and the solid oxide fuel cell power generation system described in U.S. Patent No. Reforming after mixing; Chinese patent (application number 200780010926.7) puts the reforming reactor between battery stacks, and the reformer is a reaction tube filled with catalyst, and uses the radiant heat of SOFC to heat the reformer; Chinese patent (application number 200810059387.2) After the fuel gas and water vapor are mixed and merged in the steam-water mixing chamber, they are sent together to the catalytic reformer for reforming, and the mixed gas from the reformer is connected to the anode of the solid oxide fuel cell stack. Reforming reactors or catalysts are placed on the common flow cavity and flow channels inside the battery stack, between battery layers, flow channels in single cells, and diffusion layers of battery anodes, which are called internal reforming. For example, the Chinese patent (application number 200880107952.6) is a solid oxide fuel cell with internal reforming capability, and the solid oxide fuel cell includes a catalyst layer in contact with the anode.

The tail gas combustion in the solid oxide fuel cell system is to combust the fuel tail gas flowing out of the anode and the tail gas flowing out of the battery cathode. For example, US Patent No. 7,320,836 includes a combustion chamber for the fuel tail gas flowing out of the battery and air. Because the temperature of the exhaust gas flowing out of the battery is relatively high, the combustion of the exhaust gas can be carried out by direct mixed combustion or catalytic combustion by a combustion catalyst. Catalytic combustion can make the oxidation reaction of fuel react more uniformly under the condition of lower temperature, so as to ensure the complete oxidation of fuel. As mentioned above, the combustion reaction will release a large amount of heat, which can be used for air preheating, as described in US Pat.

In the solid oxide fuel cell power generation system, the design of the reforming reaction and the catalytic combustion reactor of the tail gas needs to solve the following problems: (1) the reforming reaction is placed in a high-temperature hot zone so as to reach the temperature for the reforming reaction; (2) The reforming reaction is best to absorb the heat generated by the combustion of the tail gas, reduce the temperature of the tail gas, and realize the heat integration of the system; (3) the reforming reaction needs to have heat exchange with the fuel cell reaction, and transfer away part of the heat generated by the battery reaction in time, so that the battery The temperature distribution is relatively uniform; (4) The fuel tail gas flowing out of the battery must be completely converted in order to realize the utilization of waste heat.

Contents of the invention

The thermal-thermal coupling of various reactions in solid oxide fuel cell power plants is an important issue in establishing a stable, easy-to-control and highly integrated system structure. This patent aims at the structural characteristics and requirements of an anode-supported tubular solid oxide fuel cell with one end closed, and for the requirements of the reforming reaction of natural gas and the catalytic combustion reaction of tail gas, and proposes an anode-supported tubular solid oxide fuel cell. , A fuel distribution pipe with the functions of fuel gas reforming and tail gas catalytic combustion.

A fuel distribution pipe with the functions of fuel reforming and tail gas catalytic combustion, the fuel distribution pipe includes a support pipe with openings at both ends, the inner and outer walls of the support pipe are loaded with a catalyst layer, the catalyst layer is composed of: One or more of the aluminum and/or cerium-based composite oxides constitute a porous carrier, with at least one platinum group metal element as the main active ingredient, and at least one of the fourth period VIII group elements in the periodic table as the auxiliary The active ingredient contains at least one alkali metal element or alkaline earth metal element as an auxiliary agent; the weight content of platinum group metals in the catalyst layer is 0.01-5%; the weight content of group VIII elements in the catalyst layer is 0.5-15%; the alkali The weight content of metal elements or alkaline earth metal elements in the catalyst layer is 0.5-10%.

The fuel distribution tube includes a dense, inert support tube with open ends, and its inner wall and outer wall are loaded with a catalyst layer. The inner wall catalyst layer and the outer wall catalyst layer in the anode cavity can catalyze steam reforming of natural gas, liquefaction Petroleum gas, etc., to produce reformed gas, which is supplied to the anode support tubular solid oxide fuel cell for power generation; the outer wall catalyst layer outside the anode cavity of the battery can catalyze the combustion reaction between the fuel tail gas and air, and provide fuel for the reforming reaction and the gas flowing to the battery Thermal energy for easy heat energy recovery.

The catalytic combustion of tail gas is a strong exothermic reaction, and the steam reforming of fuel is a strong endothermic reaction. The present invention uses the wall layer catalyst to be carried on the inner and outer surfaces of the fuel distribution pipe, and its remarkable advantages are as follows: (1) it is beneficial to the uniform temperature of the catalyst, which improves the utilization efficiency of the catalyst and ensures the stable reaction; (2) it is beneficial to strengthen the heat absorption The thermal coupling of reaction and exothermic reaction strengthens the heat transfer process and improves the power generation efficiency of the system; (3) the thermal coupling of battery reaction and reforming reaction improves the power generation efficiency of the system; (4) the complete conversion of catalytic tail gas fuel is beneficial to waste heat Recycle.

The support pipe of the fuel distribution pipe of the present invention is an inert and dense high-temperature-resistant pipe with open ends, which can be a high-temperature-resistant ceramic pipe, such as an alumina pipe, a silicon carbide pipe, a corundum-mullite pipe, etc., or a High temperature resistant metal alloy tubes, such as iron-based alloys and nickel-based alloy tubes containing aluminum, zirconium, chromium and other elements. Inside the tube of the inert dense support tube is a channel for fuel gas, which can be a single-hole tube or a multi-hole tube. In the present invention, it is not only the fuel intake pipe, but also the carrier of the wall catalyst.

Both the inner wall and the outer wall of the fuel distribution pipe of the present invention are loaded with a layer of catalyst, the thickness of which is 5-300 microns, and the composition of the wall layer catalyst is: active Al ₂ O ₃ 20-80%, CeO ₂ 10-40%, ZrO ₂ 0-40%, La ₂ O ₃ 0-20%; containing at least one of platinum group metal elements such as ruthenium, rhodium, palladium, osmium, iridium, platinum, etc., the content is 0.01-5.0%; containing the periodic table of elements At least one of the group VIII elements of the fourth period in the medium-iron, cobalt, nickel, the content is 0.5-15%; it contains at least one alkali metal or alkaline earth metal element as a promoter, and the content is 0.5-10% calculated as oxides .

The technical scheme of the present invention is as follows: the support tube is an inert and dense high-temperature-resistant tube with openings at both ends, which can be a high-temperature-resistant ceramic tube, such as an alumina tube, a silicon carbide tube, a corundum-mullite tube, etc., or a high-temperature-resistant Metal alloy tubes, such as iron-based alloys and nickel-based alloy tubes containing aluminum, zirconium, chromium and other elements. The channel in the tube of the inert dense support tube is the channel of the fuel gas, which can be a single-hole tube or a multi-hole tube, and it is also a carrier of the wall layer catalyst in the present invention. The inner wall and the outer wall of the fuel distribution pipe have a catalyst layer, and the carrier material of the wall layer is one of activated alumina θ-Al ₂ O ₃ , δ-Al ₂ O ₃ , γ-Al ₂ O ₃ and cerium-containing oxide A composite support layer such as CeO ₂ , CeZrO ₂ , LaCeZrO ₂ , with a thickness of 5-300 microns. The platinum group metals are preferably rhodium and palladium, and the weight content of the platinum group metals in the wall layer catalyst is 0.01-5%. The fourth period group VIII element is a kind of iron, cobalt and nickel, and the weight content of group VIII element in the wall layer catalyst is 0.05-10%. Alkali metal and alkaline earth metal element-based cocatalysts are preferably selected from elements such as group IA lithium, sodium, and potassium and at least one of group IIA Ca, Mg, and Sr, and the weight content of alkali metal and alkaline earth metal oxides in the wall layer catalyst 0.5 to 10%.

The preparation process of the wall layer catalyst of the fuel distribution pipe is as follows:

First, the preparation of the shell carrier powder. The carrier powder used in the shell layer can be prepared by roasting aluminum hydroxide, etc. θ-Al ₂ O ₃ , δ-Al ₂ O ₃ , γ-Al ₂ O ₃ powder, or by θ-Al ₂ O ₃ Al ₂ O ₃ , γ-Al ₂ O ₃ carriers are prepared by ball milling and other methods, and the particle size of the powder is controlled below 5 microns. Cerium-containing rare earth composite oxides such as CeO ₂ , CeZrO ₂ , LaCeZrO ₂ and other powders are prepared by co-precipitation and roasting of metal salt solutions, and the powder particles are controlled to be below 5 microns by ball milling and crushing.

Second, preparation of coating slurry. Alumina powder, cerium-containing rare earth composite oxide powder, aluminum sol, organic binder, and distilled water are mixed and stirred according to a certain ratio to prepare a slurry. Alumina can be one of θ-Al2O3, δ-Al2O3, and γ-Al2O3. The rare earth composite oxide containing cerium can be one of CeO ₂ , CeZrO ₂ , and LaCeZrO ₂ . The organic binder added in the slurry can increase the bonding strength and thickness of the coating material on the pipe wall. Organic binders such as polyvinyl alcohol, methyl cellulose, etc., the amount of the organic binder is controlled at 1% of the total mass of the slurry. 1 to 10%. The aluminum sol contained in the slurry can bond the powder.

Thirdly, the slurry forms a coating on the surface of the supporting organ by spraying, dipping and other methods, preferably dip coating. The thickness of the coating can be changed as required, and is controlled between 5-300 microns, preferably 20-200 microns. The thickness of the slurry can be controlled by the concentration of the slurry to obtain the thickness of the dipping coating each time, and the thickness of the wall layer can also be increased by multiple dipping-drying processes. A support tube with a wall layer structure is obtained after dip coating.

Fourth, catalyst components are loaded. The catalyst active components include the platinum group metals of the main catalyst, the VIII group elements of the 4th period, and various co-catalyst components mentioned above. They can be loaded on the wall carrier by any suitable surface impregnation method, such as co-impregnation or step-by-step impregnation. When preparing the catalyst of the present invention, any decomposable platinum group compound and the compound of the VIII group element of the 4th cycle, such as halides, nitrates, oxides, etc., such as rhodium trichloride, palladium dichloride, chlorine Platinic acid, iron nitrate, nickel nitrate, cobalt nitrate, etc. Platinum group components, group VIII element components of the 4th period, and alkali metal and alkali metal promoters such as lithium, sodium, potassium, calcium, strontium, barium and other components can be combined with the support in any order. The co-catalyst can also be dispersed in the alumina slurry first, or surface impregnated after the wall layer is formed. The more commonly used method is to first coat the carrier coating slurry on the support hanging tube, after drying and roasting, then impregnate alkaline earth metal ions and roast, and finally impregnate the precious metals containing platinum group such as rhodium and group VIII elements of the 4th period Divide the nickel solution, dry and roast, and prepare the fuel distribution pipe containing catalytic reforming and catalytic combustion catalysts.

The fuel distribution pipe with the functions of fuel reforming and tail gas catalytic combustion of the present invention is used for an anode support tubular solid oxide fuel cell with one end open and one end closed. Hydrocarbon fuel and water vapor enter the distribution pipe through one end of the distribution pipe, and flow to the fuel cell in the pipe. After passing through the preheating section, the fuel gas reaches the steam reforming temperature, and the steam reforming reaction occurs under the action of the wall catalyst. At the same time, the catalyst layer on the outer wall of the tube catalyzes the combustion of the fuel flowing out of the battery, providing heat for the reforming reaction, so that the reaction heat inside and outside the supporting tube is coupled. The distribution pipe part placed in the tubular battery, whether it is the inner wall layer catalyst or the outer wall layer catalyst, can use the heat released by the fuel cell to carry out the reforming reaction of fuel. The fuel flowing out of the fuel distribution pipe, on the one hand, undergoes an electrochemical reaction on the battery, and on the other hand, the catalyst on the outer wall of the pipe can be used to continue the fuel reforming reaction. After the fuel flows out of the battery, it mixes with the air flowing out of the battery, and under the action of the catalyst on the outer wall of the tube, a catalytic combustion reaction occurs.

The fuel distribution pipe with the functions of fuel gas reforming and tail gas catalytic combustion of the present invention has a section outside the battery, and its main functions are: preheating of fuel gas, combustion of tail gas and reforming reaction, and realizing the heat of the two reactions coupling. One section is located in the battery to realize the thermal coupling of the reforming reaction and the battery reaction. Therefore, the power generation system of the solid oxygen fuel cell supported by the anode of the fuel distribution pipe of the present invention is beneficial to stabilizing the temperature of each part and protecting the stability of the system on the one hand. On the other hand, it is beneficial to improve the power generation efficiency of the system. The heat released by the battery reaction and the tail gas fuel reaction is absorbed by the fuel steam reforming reaction, which can achieve higher power generation efficiency of the system. In particular, the catalytic combustion reaction that releases a large amount of heat, the fuel reforming reaction that absorbs a large amount of heat and the air preheating are integrated into the catalytic combustion reaction chamber. The power generation system using the fuel distribution pipe has the following three characteristics: 1) It realizes the heat absorption and release coupling of the catalytic combustion reaction and the catalytic reforming reaction heat; 2) It is beneficial to the cooling of the exhaust gas and prevents the temperature of the catalytic combustion chamber from being too high , which is convenient for system control; 3) Reasonable system heat flow characteristics are convenient for intelligent management of power stations. 4) It avoids the use of rotating parts in the high temperature zone to mix the exhaust gas with the newly inflowing fuel, which improves the reliability of the whole system.

In order to better clarify the application of the distribution pipe with the functions of fuel gas reforming and tail gas catalytic combustion of the present invention, the present invention provides partial structural diagrams, and the diagram notes are as follows.

Description of drawings

Figure 1. Structural diagram of the fuel distribution pipe with fuel gas reforming and tail gas catalytic combustion functions (A), the assembly structure of the fuel distribution pipe and the anode support tubular battery (B), and the fuel exhaust on the inner and outer walls of the fuel distribution pipe Schematic diagram of thermal coupling of catalytic combustion and reforming reaction (C). 1. Preheating section; 2. Inner wall and outer wall loaded catalyst layer section; 3. Preheating section (no catalyst wall layer); 4. Reaction coupling section (catalytic combustion of outer wall layer and catalytic reforming of inner wall layer); 5. Full Catalytic reforming section (catalytic reforming of inner and outer wall layers); 6. Air; 7. Anode support tubular battery; 8. Natural gas and water vapor; 9. Fuel distribution pipe; 10. Catalyst layer on the outer wall; 11. Support pipe 12. Catalyst layer on the inner wall; 13. CH ₄ , H ₂ , CO and O ₂ ; 14. CO ₂ and H ₂ O; 15. CH ₄ and H ₂ O; 16. CO and H ₂ .

detailed description

The present invention aims at the characteristics and requirements of the power station structure of an anode-supporting tubular solid oxide fuel cell with one end closed (Chinese Patent Application No. 2011101978022), and in view of the above-mentioned requirements for fuel reforming and tail gas combustion, and proposes a fuel gas catalytic regenerator. The fuels with tail gas catalytic combustion function are piped separately, which mainly has the following characteristics: (1) The reforming reaction and combustion reaction are placed inside and outside the fuel distribution pipe respectively, and both are in the high temperature area; (2) The fuel reforming reaction and the The catalytic combustion reaction of fuel exhaust gas can be thermally coupled through the wall of the fuel distribution pipe. (3) The thermal coupling of the battery reaction and the reforming reaction; (4) The use of a catalyst in the combustion reaction is conducive to the complete combustion of the tail gas and the utilization of waste heat.

The present invention will be described in further detail and specifically below.

Example 1

2000 grams of alumina sol (containing 5wt% alumina), 1500 grams of distilled water, and 1500 grams of 20wt% polyvinyl alcohol were prepared into a sol solution, and the sol solution was stirred at 75° C. for 2 hours to make the sol uniform. Add 1500g of γ-Al ₂ O ₃ and 1500g of cerium-zirconium composite oxide powder into the above sol solution, stir evenly, and then ball mill the above mixed slurry for 30 minutes to obtain γ-Al ₂ O ₃ particles and particles of cerium-zirconium composite oxide Uniformly dispersed slurry.

Take 2 corundum tubes with an outer diameter of 12 mm, an inner diameter of 9 mm, and a length of 1.6 m (tube numbers I and II). This I branch pipe was dip-coated in the above-mentioned slurry, and the dip-coating length was 1.5 meters, then dried at 120° C. for 8 hours, and baked at 950° C. for 4 hours to obtain a composite carrier pipe I with porous carriers on the inner and outer walls. Dip-coat the II tube in the above slurry, the dip-coating length is 1.5 meters, then dry at 120°C for 8 hours, and bake at 950°C for 4 hours; then dip-coat, dry and bake once in the slurry to obtain the inner and outer walls. Composite carrier tube of porous carrier (II).

19.5 g of RhCl ₃ ·3H ₂ O, 293 g of Ni(NO ₃ ) ₂ ·6H ₂ O, 550 g of Mg(NO ₃ ) ₂ ·6H ₂ O were heated and dissolved in 1000 g of deionized water to prepare a mixed impregnation solution. A section of the wall layer carrier of the composite carrier tube (I) obtained above was immersed in the above-mentioned dipping solution, and then taken out and dried at 150C for 6 hours. In order to increase the loading capacity of the catalyst, the composite carrier tube was impregnated and dried once more. Then, the composite pipe was calcined at 650° C. for 4 hours to obtain a fuel distribution pipe (I) with a catalyst layer. Electron microscopy results show that the thickness of the inner and outer wall layers is 24 microns, and the elemental analysis shows that the weight composition of the catalytic layer is as follows: _Al2O3 is 44%, _CeO2 is 20.5%, _ZrO2 is ₁₈ %, Rh is 1.05%, and Ni is 7.4% , MgO is 6.5%.

21.6 g of RuCl ₃ ·3H ₂ O, 253 g of Ni(NO ₃ ) ₃ ·6H ₂ O, and 350 g of LiNO ₃ were heated and dissolved in 1000 g of deionized water to prepare a mixed impregnation solution. A section of the wall layer carrier of the composite carrier tube (II) obtained above was immersed in the above-mentioned impregnating solution, then taken out and dried at 150°C, and baked at 600°C for 4 hours to obtain a fuel distribution pipe with a catalyst layer (II ). Electron microscopy results show that the thickness of the inner and outer wall layers is 53 microns, and elemental analysis shows that the weight composition of the catalytic layer is as follows: _Al2O3 is 45%, CeO2 is ₂₀ %, _ZrO2 is ₁₉ %, Ru is 0.85%, and Ni is 6.5% , _Li2O is 4.5%.

Example 2

1500 grams of alumina sol (containing 5 wt % alumina), 2000 grams of distilled water, and 1800 grams of 20 wt % polyvinyl alcohol were prepared into a sol solution. The sol solution was stirred at 75° C. for 2 hours to make the sol homogeneous. Add 1500g of γ _{- Al2O3} and 1500g of lanthanum-cerium-zirconium composite oxide powder into the above-mentioned sol solution, stir evenly, then ball mill the above-mentioned mixed slurry for 40 minutes, and then add defoamer to obtain γ _{- Al2O3} particles and A slurry in which particles of lanthanum cerium zirconium composite oxide are uniformly dispersed.

Use a corundum-mullite tube (III) with an outer diameter of 16 mm, four holes with an inner diameter of 4 mm, and a length of 1.6 meters for dip coating, and the dip coating length is 1.5 meters. Then it was dried at 120°C for 8 hours and fired at 600°C for 4 hours. Then, it was dip-coated again, dried and then baked at 900° C. for 4 hours to obtain a corundum-mullite-supported composite carrier tube (III) with porous carriers on the inner and outer walls.

16.8 g Pd(NO ₃ ) 3H ₂ O, 120.4 g Ni(NO ₃ ) ₂ 6H ₂ O, 118.4 g Co(NO ₃ ) ₃ 6H ₂ O, 350 g Ca(NO ₃ ) ₂ 6H ₂ O was heated and dissolved in 1000 g of deionized water to prepare a mixed impregnation solution. A section of the walled carrier of the composite carrier tube obtained above was immersed in the above impregnating solution, and then taken out and dried at 150° C. for 6 hours. Then, the composite pipe was calcined at 650° C. for 4 hours to obtain a fuel distribution pipe (III) with a catalyst layer. Electron microscopy results show that the thickness of the inner and outer wall layers is 26 microns, and elemental analysis shows that the weight composition of the catalytic layer is as follows: _Al2O3 is ₄₃ %, CeO2 is ₁₆ %, ZrO2 is 17.2 _% , _La2O3 is _6.2 %, Pd 0.94%, Ni 3.5%, Co 3.6%, CaO 3.5%.

Example 3

The distribution pipe is used as the anode support tubular solid oxide fuel cell (the anode support tubular solid oxide fuel cell is tubular, one end is closed and the other end is open, the inside is the anode support layer, the outside is the cathode layer, the anode support layer and the cathode layer There is an electrolyte membrane between them) the fuel inlet pipe; during use, the inlet end is connected to the common fuel chamber, the outlet is connected to the anode chamber of the anode support tubular battery, and one section of the distribution pipe is located in the anode chamber of the anode support tubular battery. On the outside of the anode-supported tubular cell.

The distribution pipe (I-III) obtained above is assembled as shown in Figure 1 with an outer diameter of 25 mm, an inner diameter of 20 mm, a length of 1.2 meters, and an end-closed anode support tubular battery pack with an effective electrode length of 1 meter. tube battery, the distribution tube is placed within 1.1 meters of the length of the battery cavity. The single-tube battery is heated by an electric furnace. The natural gas and water vapor are passed into the single cell according to the molar ratio of 1:1, the total flow rate is 0.600 liters/minute, the air outside the battery is 12 liters/minute, the temperature of the battery is at 800 ℃, and the output voltage of the battery is measured as The output current and output power at 0.8V were used to measure the content of methane, hydrogen and CO in the tail gas flowing out from the combustion. The test results are shown in Table 1.

Table 1 The output current, power and total mass content of methane, hydrogen and carbon monoxide in the exhaust gas of the fuel cell assembled with the fuel distribution pipe at 800°C.

Claims (9)

1. there is a fuel rail for fuel reforming and tail gas catalyzed combustion function, it is characterized in that:

This fuel rail comprises the stay pipe of a both ends open, and the inner and outer wall of stay pipe is all supported with catalyst layer, and catalyst layer consists of: formed porous carrier with one or more in aluminium oxide and/or cerium-based composite oxides,

Using at least one platinum metal element as main active ingredient, in the periodic table of elements in period 4 VIII element at least one as auxiliary active ingredient, containing at least one alkali metal or alkali earth metal as auxiliary agent;

The weight content of platinum metal in catalyst layer is 0.01 ~ 5%; The weight content 0.5 ~ 15% of VIII element in catalyst layer; Alkali metal or the alkali earth metal weight content 0.5 ~ 10% in catalyst layer.

2. fuel rail according to claim 1, is characterized in that:

Platinum metal element is one or more in ruthenium, rhodium, palladium, osmium, iridium, platinum, in the periodic table of elements, period 4 VIII element is one or more in iron, cobalt, nickel, alkali metal oxide is one or more in IA race lithium, sodium, potassium, and alkaline earth oxide is one or more in the calcium of IIA, magnesium, strontium, barium.

3. fuel rail according to claim 1, is characterized in that:

The porous carrier materials of the inner and outer wall catalyst layer employing of stay pipe is the θ-Al in activated alumina ₂o ₃, δ-Al ₂o ₃, γ-Al ₂o ₃, CeO in cerium-based composite oxides ₂, CeZrO ₂, LaCeZrO ₂one or two or more kinds complex carrier; Catalyst layer thickness is 5-300 micron.

4. fuel rail according to claim 3, is characterized in that:

Porous carrier materials is activated alumina θ-Al ₂o ₃, δ-Al ₂o ₃, γ-Al ₂o ₃in one or two or more kinds and cerium-based composite oxides CeO ₂, CeZrO ₂, LaCeZrO ₂in one or two or more kinds mixing complex carrier.

5. fuel rail according to claim 4, is characterized in that:

In porous carrier materials, the weight content of each component is Al ₂o ₃20 ~ 80%, CeO ₂10 ~ 40%, ZrO ₂0 ~ 40%, La ₂o ₃0 ~ 20%.

6. fuel rail according to claim 1, is characterized in that:

Stay pipe is both ends open, inertia, fine and close high-temperature resistant tube, is resistant to elevated temperatures earthenware or resistant to elevated temperatures metal alloy pipe, and this fuel rail is single duct pipe, or has multiple ducts pipe in more than two coaxial ducts.

7. fuel rail according to claim 6, is characterized in that:

Resistant to elevated temperatures earthenware is alumina tube, carborundum tube or corundum-mullite pipe, the ferrous alloy of one or two or more kinds element or nickel-based alloy pipe in resistant to elevated temperatures metal alloy Guan Weihan aluminium, zirconium, chromium; The best duct number 2-4 of multiple ducts pipe is individual.

8. an application for fuel rail according to claim 1, is characterized in that:

Its anode-supported cast Solid Oxide Fuel Cell fuel air pipe closed as one end; In use entrance point connects common fuel chamber, and outlet passes in anode-supported cast galvanic anode chamber, and one section of distributing pipe is in the anode cavities of anode-supported cast battery, one section of outside being in anode-supported cast battery.

9. the application of fuel rail according to claim 8, is characterized in that:

The entrance point of this fuel rail connects common fuel chamber, the port of export stretches into the anode cavities of anode-supported cast battery, inwall catalyst layer and be in outer wall catalyst layer in galvanic anode chamber can catalyzed aqueous vapour reforming natural gas and/or raw liquefied petroleum gas, produce reformed gas, the generating of supply anode-supported cast Solid Oxide Fuel Cell; The outer wall catalyst layer being in outside batteries is also catalytic fuel tail gas and air generation combustion reaction, for reforming reaction and preheating gas provide heat energy.