An electrode sintering device and method for a molten carbonate fuel cell

Abstract

An electrode sintering device and method for a molten carbonate fuel cell provided by the present invention belong to the technical field of hydrogen energy and fuel cells. The electrode sintering device for a molten carbonate fuel cell includes: at least two sintering heating furnaces; an air outlet of the sintering heating furnace is communicated with an air inlet of the adjacent sintering heating furnace. In the electrode sintering device for a molten carbonate fuel cell of the present invention, hydrogen is introduced into the sintering heating furnace, and the hydrogen can flow in the sintering furnaces connected in series in sequence, that is, recycled, so as to improve the utilization efficiency of the gas.

Description

Technical Field

[0001] The present invention relates to the technical field of hydrogen energy and fuel cells, and particularly relates to an electrode sintering device and method for a molten carbonate fuel cell. Background Art

[0002] As a new type of power generation technology, fuel cells have the advantages of pollution-free and modular assembly. As a type of fuel cell, molten carbonate fuel cells belong to the category of high-temperature fuel cells. Compared with low-temperature fuel cells, they have the characteristics of wide fuel sources, no need for precious metals as catalysts, and relatively high exhaust gas temperatures.

[0003] A molten carbonate fuel cell mainly consists of bipolar plates, electrodes, diaphragms, etc., among which the electrodes play an important role; the electrode composition is metallic nickel, the anode is metallic nickel, and the cathode is nickel oxide. Currently, the electrodes are mainly sintered in an electrode sintering furnace. During the sintering process, hydrogen needs to be introduced into the sintering furnace to react with the electrode blank. However, in traditional sintering, hydrogen enters from the inlet of the sintering furnace and is directly exhausted after the reaction, resulting in relatively serious waste of hydrogen. Summary of the Invention

[0004] Therefore, the technical problem to be solved by the present invention is to overcome the defect of relatively serious waste of hydrogen during the electrode sintering process in the prior art, so as to provide an electrode sintering device for a molten carbonate fuel cell.

[0005] The present invention also provides an electrode sintering method for a molten carbonate fuel cell.

[0006] To solve the above technical problem, an electrode sintering device for a molten carbonate fuel cell provided by the present invention includes:

[0007] Sintering heating furnaces, having at least two; the gas outlet of the sintering heating furnace is communicated with the gas inlet of the adjacent sintering heating furnace.

[0008] As a preferred solution, the sintering heating furnace includes:

[0009] A first sintering heating furnace, having a first gas inlet and a first gas outlet;

[0010] A second sintering heating furnace, having a second gas inlet and a second gas outlet; the second gas inlet is communicated with the first gas outlet through a connecting pipeline.

[0011] As a preferred solution, a first absorption device is provided on the connecting pipeline; the first absorption device contains an absorbent for absorbing carbon dioxide and water vapor.

[0012] As a preferred solution, the absorbent in the first absorption device is soda lime.

[0013] As a preferred solution, it further includes:

[0014] A second absorption device, which is communicatively connected to the second air outlet; the second absorption device contains an absorbent for absorbing carbon dioxide.

[0015] As a preferred solution, the absorbent in the second absorption device is an aqueous solution of calcium hydroxide.

[0016] As a preferred solution, a hydrogen combustion device is provided at the air outlet of the second absorption device.

[0017] As a preferred solution, electrode racks are provided in both the first sintering heating furnace and the second sintering heating furnace.

[0018] The present invention also provides a method for sintering electrodes of a molten carbonate fuel cell, including the following steps:

[0019] Put the electrode blank of the molten carbonate fuel cell into the first sintering heating furnace and the second sintering heating furnace;

[0020] Raise the temperature in the first sintering heating furnace and the second sintering heating furnace to a first temperature, and introduce air during the temperature increase process;

[0021] Raise the temperature in the first sintering heating furnace and the second sintering heating furnace to a second temperature, and first introduce nitrogen and then hydrogen during the temperature increase process;

[0022] Keep the temperature in the first sintering heating furnace and the second sintering heating furnace at the second temperature;

[0023] Lower the temperature in the first sintering heating furnace and the second sintering heating furnace to the first temperature, and introduce hydrogen during the temperature decrease process;

[0024] Lower the temperature in the first sintering heating furnace and the second sintering heating furnace from the first temperature to room temperature, and introduce nitrogen during the temperature decrease process.

[0025] It is characterized in that the first temperature is 500 °C and the second temperature is 850 °C.

[0026] The technical solution of the present invention has the following advantages:

[0027] 1. The electrode sintering device of the molten carbonate fuel cell provided by the present invention includes at least two sintering heating furnaces; the air outlet of the sintering heating furnace is communicatively connected to the air inlet of the adjacent sintering heating furnace; hydrogen is introduced into the sintering heating furnace, and hydrogen can flow in the sequentially connected sintering furnaces, that is, recycled, improving the utilization efficiency of the gas.

[0028] 2. The electrode sintering device of the molten carbonate fuel cell provided by the present invention. Further, the sintering heating furnace includes a first sintering heating furnace and a second sintering heating furnace; the first air outlet of the first sintering heating furnace is communicated with the second air inlet of the second sintering heating furnace through a connecting pipeline; during the sintering process, hydrogen needs to be introduced. After the hydrogen used in the first sintering heating furnace is exhausted, it can enter the second sintering heating furnace through the connecting pipeline, and the hydrogen can be recycled, which can effectively improve the utilization rate of hydrogen.

[0029] 3. The electrode sintering device of the molten carbonate fuel cell provided by the present invention is provided with a first absorption device on the connecting pipeline, which is used to absorb carbon dioxide and water in the exhaust gas discharged from the first sintering heating furnace and then enter the second sintering heating furnace; the concentration of the exhaust gas after being absorbed by the first absorption device is higher, which is beneficial to the sintering reaction in the second sintering heating furnace.

[0030] 4. The electrode sintering device of the molten carbonate fuel cell provided by the present invention is provided with a second absorption device at the second air outlet, which is used to absorb the carbon dioxide generated in the second sintering heating furnace and reduce the amount of carbon dioxide discharged into the atmosphere.

[0031] 5. The electrode sintering device of the molten carbonate fuel cell provided by the present invention is provided with a hydrogen combustion device at the air outlet of the second absorption device to burn the unreacted hydrogen and reduce the probability of danger when discharged into the air. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the following drawings are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0033] Figure 1 It is a schematic structural diagram of the electrode sintering device of the molten carbonate fuel cell of the present invention.

[0034] Description of the reference numerals:

[0035] 1. First sintering heating furnace; 2. Second sintering heating furnace; 3. First absorption device; 4. Second absorption device; 5. Hydrogen combustion device; 6. First air inlet. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0036] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0037] In the description of the present invention, it should be noted that the orientation or positional relationship indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present invention.

[0038] In the description of the present invention, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0039] In addition, the technical features involved in different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0040] Embodiment 1

[0041] An electrode sintering device for a molten carbonate fuel cell provided in this embodiment includes: at least two sintering heating furnaces; the sintering heating furnaces are arranged in series, that is, the air outlet of one sintering heating furnace is communicated with the air inlet of the adjacent sintering heating furnace. The introduced hydrogen can be recycled to increase the utilization rate of hydrogen.

[0042] In this solution, as Figure 1 shown, the sintering heating furnace includes: a first sintering heating furnace 1 and a second sintering heating furnace 2; the first sintering heating furnace 1 has a first air inlet 6 and a first air outlet; the second sintering heating furnace 2 has a second air inlet and a second air outlet; the first air outlet is communicated with the second air inlet through a connecting pipeline. After the gas in the first sintering heating furnace 1 is discharged, it can enter the second sintering heating furnace 2 through the connecting pipeline, and the gas can be recycled.

[0043] Further, a first absorption device 3 is provided on the connecting pipeline. An absorbent is contained in the first absorption device 3, and the absorbent is soda lime, which is used to absorb carbon dioxide and water vapor. After the tail gas in the first sintering heating furnace 1 passes through the first absorption device 3, it then enters the second sintering heating furnace 2. Among them, the tail gas includes carbon dioxide, water, and unreacted air generated during the process of sintering the electrode blank. The first absorption device 3 absorbs carbon dioxide and water in the tail gas to increase the gas concentration in the second sintering heating furnace 2.

[0044] A second absorption device 4 is connected to the second air outlet of the second sintering heating furnace 2 through a pipeline. An aqueous solution of calcium hydroxide is contained in the second absorption device 4, which is used to absorb carbon dioxide in the tail gas discharged from the second sintering heating furnace 2 and reduce greenhouse gas emissions.

[0045] A hydrogen combustion device 5 is provided at the air outlet of the second absorption device 4. The hydrogen that did not participate in the reduction reaction is burned through the hydrogen combustion device 5 and then discharged into the atmosphere.

[0046] Electrode racks are provided in both the first sintering heating furnace 1 and the second sintering heating furnace 2, and the electrode racks are used to place the molten carbonate fuel cell electrode blanks to be roasted.

[0047] Example 2

[0048] An electrode sintering method for a molten carbonate fuel cell provided in this example includes the following steps:

[0049] Place the molten carbonate fuel cell electrode blank on the electrode racks in the first sintering heating furnace 1 and the second sintering heating furnace 2.

[0050] Start heating the first sintering heating furnace 1 and the second sintering heating furnace 2 at a heating rate of 3 °C / min until the first temperature, and the first temperature is 500 °C. During this heating process, air is introduced into the nitrogen and air inlets of the first air inlet 6. After heating, some organic substances in the electrode blank burn, and the gas generated by combustion and the unreacted air are passed through the first absorption device 3 through the first air outlet and then enter the second sintering heating furnace 2 to participate in the reaction. The tail gas generated at the second air outlet of the second sintering heating furnace 2 is absorbed by the calcium hydroxide solution in the second absorption device 4 to reduce greenhouse gas emissions.

[0051] After the temperatures in the first sintering furnace 1 and the second sintering furnace 2 rise to 500 °C, the supply of air is stopped. Meanwhile, nitrogen is introduced through the nitrogen and air inlet of the first air inlet 6 to purge the internal air, discharging the air in the first sintering furnace 1 and the second sintering furnace 2. After the air is discharged, hydrogen is introduced through the hydrogen inlet of the first air inlet 6. At the same time, the temperatures of the first sintering furnace 1 and the second sintering furnace 2 are raised to 850 °C at a heating rate of 3 °C / min to perform a reduction treatment on the molten carbonate fuel cell electrode blank. Meanwhile, the first sintering furnace 1 and the second sintering furnace 2 are kept at 850 °C for 30 - 60 min. The reacted hydrogen passes through the second air outlet in the second sintering furnace 2, passes through the second absorption device 4, and then burns in the hydrogen combustion device 5 and is discharged into the atmosphere.

[0052] The first sintering furnace 1 and the second sintering furnace 2 start to cool down from 850 °C, and hydrogen is continuously introduced during the cooling process. When the temperature drops to 500 °C, the supply of hydrogen is stopped and nitrogen is introduced for gas protection until the temperature drops to room temperature.

[0053] Obviously, the above embodiments are merely examples given for clear illustration and are not limitations on the implementation manners. For those of ordinary skill in the art, other different forms of changes or variations can be made based on the above description. It is not necessary and impossible to list all the implementation manners here. And the obvious changes or variations derived therefrom are still within the protection scope of the present invention.

Claims

1. An electrode sintering device for a molten carbonate fuel cell, characterized in that, Comprising: Sintering heating furnaces, with at least two; The air outlet of the sintering heating furnace is communicated with the air inlet of the adjacent sintering heating furnace; The sintering heating furnace includes: The first sintering heating furnace (1), having a first air inlet (6) and a first air outlet; The second sintering heating furnace (2), having a second air inlet and a second air outlet; the second air inlet is communicated with the first air outlet through a connecting pipeline; A first absorption device (3) is arranged on the connecting pipeline; the first absorption device (3) contains an absorbent for absorbing carbon dioxide and water vapor.

2. The electrode sintering device for a molten carbonate fuel cell according to claim 1, characterized in that, The absorbent in the first absorption device (3) is soda lime.

3. The electrode sintering device for a molten carbonate fuel cell according to claim 1, characterized in that, Also included is: A second absorption device (4), which is communicated with the second air outlet; the second absorption device (4) contains an absorbent for absorbing carbon dioxide.

4. The electrode sintering device for a molten carbonate fuel cell according to claim 3, characterized in that, The absorbent in the second absorption device (4) is an aqueous solution of calcium hydroxide.

5. The electrode sintering device for a molten carbonate fuel cell according to claim 3, characterized in that, A hydrogen combustion device (5) is arranged at the air outlet of the second absorption device (4).

6. The electrode sintering device for a molten carbonate fuel cell according to claim 1, characterized in that, Electrode frames are arranged in both the first sintering heating furnace (1) and the second sintering heating furnace (2).

7. An electrode sintering method for a molten carbonate fuel cell, characterized in that, Including the following steps: Put the molten carbonate fuel cell electrode blank into the first sintering heating furnace (1) and the second sintering heating furnace (2); Raise the temperature in the first sintering heating furnace (1) and the second sintering heating furnace (2) to the first temperature, and introduce air during the temperature rise; Raise the temperature in the first sintering heating furnace (1) and the second sintering heating furnace (2) to the second temperature, and first introduce nitrogen and then hydrogen during the temperature rise; Keep the temperature in the first sintering heating furnace (1) and the second sintering heating furnace (2) at the second temperature; Lower the temperature in the first sintering heating furnace (1) and the second sintering heating furnace (2) to the first temperature, and introduce hydrogen during the temperature drop; Lower the temperature in the first sintering heating furnace (1) and the second sintering heating furnace (2) from the first temperature to room temperature, and introduce nitrogen during the temperature drop.

8. The electrode sintering method for a molten carbonate fuel cell according to claim 7, characterized in that, The first temperature is 500 °C, and the second temperature is 850 °C.

Images