Natural gas desulfurization device for solid oxide fuel cell

Abstract

The invention relates to the technical field of chemical engineering, and particularly provides a natural gas desulfurization device for a solid oxide fuel cell, which comprises a tank body, a lower desulfurization cavity lower sieve plate, a lower desulfurization cavity, a lower desulfurization cavity upper sieve plate, a gas buffer area, an upper desulfurization cavity lower sieve plate, an upper desulfurization cavity and an upper desulfurization cavity upper sieve plate are respectively arranged in the tank body from bottom to top, the bottom of the tank body is communicated with a lower filling port, and the top of the tank body is communicated with an upper filling port; and an air inlet is communicated and penetrated at the bottom of the side surface of the tank body and at the bottom of the lower sieve plate of the lower desulfurization cavity. According to the device, two desulfurizing agent filling cavities are provided, H2S is firstly removed by using an iron oxide / zinc oxide desulfurizing agent, and then tetrahydrothiophene is removed by using a tetrahydrothiophene removing desulfurizing agent, so that not only can the desulfurization requirement be met, but also the desulfurization cost is saved, meanwhile, loading and unloading ports are respectively designed for the two desulfurizing agent filling cavities, and the desulfurizing agents can be respectively and quickly loaded and unloaded.

Description

Technical Field

[0001] The invention belongs to the technical field of chemical engineering, and in particular relates to a natural gas desulfurization device for solid oxide fuel cells. Background Art

[0002] A fuel cell is an energy conversion device that can directly convert chemical energy into electrical energy. The conversion process occurs between fuel and oxidant. The operation of the fuel cell requires the supply of fuel gas. Untreated fuel gas contains tetrahydrothiophene and hydrogen sulfide. These sulfur-containing components entering the fuel cell system will poison the fuel cell (react with the anode catalyst) and make it fail. Therefore, the fuel gas needs to be desulfurized before being supplied to the system.

[0003] At present, the removal technology of H2S is relatively mature. Desulfurizers with iron oxide and zinc oxide as the main components can achieve good removal effects. The removal of organic sulfur is more difficult. In industrial treatment of natural gas, desulfurizer pre-desulfurization is often used to remove H2S first, and then the natural gas is subjected to hydrogenation reduction reaction to reduce the organic sulfur to H2S before being removed by desulfurizer.

[0004] In response to this situation, some domestic institutions have developed desulfurizers that can not only remove H2S but also directly remove tetrahydrothiophene. However, the sulfur capacity is relatively small, generally below 2%, which is a big gap compared to the 10%-20% sulfur capacity of iron oxide and zinc oxide desulfurizers. Directly using desulfurizers to remove tetrahydrothiophene requires a large amount of desulfurizers, and using two types of desulfurizers separately requires two sets of desulfurization devices.

[0005] The industrial desulfurization solution is relatively complicated for solid fuel cells. In addition to requiring an additional source of hydrogen, the temperature and pressure requirements of the reduction reaction (generally 300-400°C, 2-4MPa) may be incompatible with the pressure of the fuel cell system, which wastes energy and increases control costs.

[0006] A single desulfurizer, iron oxide / zinc oxide desulfurizer, cannot effectively remove tetrahydrothiophene; the desulfurizer for removing tetrahydrothiophene has low sulfur capacity and high cost, and H2S not only affects the removal of tetrahydrothiophene, but also reduces the economic effect. Summary of the invention

[0007] In view of the shortcomings of the prior art, the present invention aims to provide a natural gas desulfurization device for solid oxide fuel cells, which solves the problems of natural gas desulfurization and replacement of desulfurizers.

[0008] To achieve the above-mentioned objectives, the present invention provides the following technical solutions: A natural gas desulfurization device for a solid oxide fuel cell, comprising a tank body, wherein the interior of the tank body is respectively provided with a lower desulfurization chamber lower sieve plate, a lower desulfurization chamber, an upper sieve plate of the lower desulfurization chamber, a gas buffer zone, an upper desulfurization chamber lower sieve plate, an upper desulfurization chamber, and an upper desulfurization chamber upper sieve plate from bottom to top, the bottom of the tank body is connected to a lower filling port, the top of the tank body is connected to an upper filling port, the bottom of the side surface of the tank body and the position located at the bottom of the lower sieve plate of the lower desulfurization chamber are connected and penetrated with an air inlet, and the top of the side surface of the tank body and the position located at the top of the upper sieve plate of the upper desulfurization chamber are connected and penetrated with an air outlet.

[0009] Preferably, the lower desulfurization chamber and the upper desulfurization chamber are respectively filled with desulfurizers of two different specifications.

[0010] Preferably, the lower desulfurization chamber and the upper desulfurization chamber are independently loaded and removed with desulfurizing agent through the upper filling port and the lower filling port respectively.

[0011] Preferably, the packing ends of the lower filling port and the upper filling port are both detachably mounted with flanges via bolts.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] 1. Solid oxide fuel cells have high desulfurization requirements, and most of them require the sulfur content to be below 1PPM. The sulfur components of natural gas include organic sulfur components such as H2S and tetrahydrothiophene. In order to meet the desulfurization requirements and control costs at the same time, it is necessary to use desulfurizers of different specifications to remove organic sulfur components such as H2S and tetrahydrothiophene respectively. However, the present invention provides two desulfurizer filling chambers. H2S is first removed by iron oxide / zinc oxide desulfurizer, and then tetrahydrothiophene is removed by desulfurizer. This can not only meet the desulfurization requirements, but also save desulfurization costs. At the same time, loading and unloading ports are designed for the two desulfurizer filling chambers, so that the desulfurizers can be quickly loaded and unloaded respectively.

[0014] 2. Aiming at the desulfurization targets of different systems, the present invention can flexibly combine desulfurizers and adopt the desulfurization agent combination with the highest economic benefit to achieve the desulfurization target.

[0015] 3. The desulfurizer needs to be replaced after 1-2 years of use. The present invention can load and disassemble the desulfurizer separately, and can quickly replace the desulfurizer to meet the desulfurizer replacement needs at different times. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 This is a schematic diagram of the appearance structure of the present invention;

[0017] Figure 2 It is a schematic diagram of the internal structure of the tank body of the present invention;

[0018] Figure 3 This is a schematic diagram of the structure of the flange connecting the lower filling port of the present invention;

[0019] Figure 4 It is a schematic diagram of the structure of the upper filling port connecting flange of the present invention.

[0020] In the figure: 1. tank body; 2. air inlet; 3. air outlet; 4. lower filling port; 5. upper filling port; 6. lower desulfurization chamber; 7. gas buffer zone; 8. upper desulfurization chamber; 9. lower sieve plate of lower desulfurization chamber; 10. upper sieve plate of lower desulfurization chamber; 11. lower sieve plate of upper desulfurization chamber; 12. upper sieve plate of upper desulfurization chamber; 13. bolts; 14. flange. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0022] Refer to the following Figure 1-Figure 4 A natural gas desulfurization device for a solid oxide fuel cell provided in one embodiment of the present application is described.

[0023] A natural gas desulfurization device for a solid oxide fuel cell comprises a tank body 1, wherein the interior of the tank body 1 is respectively provided with a lower desulfurization chamber lower sieve plate 9, a lower desulfurization chamber 6, a lower desulfurization chamber upper sieve plate 10, a gas buffer zone 7, an upper desulfurization chamber lower sieve plate 11, an upper desulfurization chamber 8, and an upper desulfurization chamber upper sieve plate 12 from bottom to top, a lower filling port 4 is provided at the bottom of the tank body 1, an upper filling port 5 is provided at the top of the tank body 1, an air inlet 2 is provided at the bottom of the side surface of the tank body 1 and located at the bottom of the lower desulfurization chamber lower sieve plate 9, and an air outlet 3 is provided at the top of the side surface of the tank body 1 and located at the top of the upper desulfurization chamber upper sieve plate 12.

[0024] Furthermore, the lower desulfurization chamber 6 and the upper desulfurization chamber 8 are respectively filled with two desulfurizers of different specifications, and the size and volume of the tank body 1, the lower desulfurization chamber 6 and the upper desulfurization chamber 8 can be customized and adjusted according to the actual filling amount of the device.

[0025] Furthermore, the lower desulfurization chamber 6 and the upper desulfurization chamber 8 are independently loaded and removed with desulfurizing agent through the upper filling port 5 and the lower filling port 4 respectively.

[0026] In a further embodiment, the filling ends of the lower filling port 4 and the upper filling port 5 are detachably mounted with flanges 14 via bolts 13. The flanges 14 are arranged to facilitate sealing of the upper filling port 5 and the lower filling port 4, respectively, and facilitate rapid loading and unloading of the desulfurizer.

[0027] In combination with the above-mentioned embodiments, the working principle and specific working process of a natural gas desulfurization device for solid oxide fuel cells of the present application are described: natural gas gas enters the tank body 1 through the air inlet 2, and enters the lower desulfurization chamber 6 through the lower sieve plate 9 of the lower desulfurization chamber. The sulfur components such as H2S in the natural gas react with the iron oxide / zinc oxide therein to achieve the purpose of removing H2S; thereafter, the natural gas enters the gas buffer zone 7 through the upper sieve plate 10 of the lower desulfurization chamber, and then enters the upper desulfurization chamber lower sieve plate 11 through the lower sieve plate 11 of the upper desulfurization chamber. After the tetrahydrothiophene in the natural gas is adsorbed by the tetrahydrothiophene removal desulfurizer, the desulfurized natural gas passes through the upper sieve plate 12 of the upper desulfurization chamber and the air outlet 3 to enter the subsequent processing flow.

[0028] Reaction equation: ZnO+H2S=ZnS+H2O

[0029] Fe2O3·H2O+3H2S=Fe2S3·H2O+3H2O

[0030] When the upper desulfurization chamber 8 is filled with desulfurizer, the device is placed upright, the upper filling port 5 is opened, and the desulfurizer is filled into the upper desulfurization chamber 8 through the upper filling port 5. When the height of the desulfurizer is slightly higher than the bottom of the upper filling port 5, the upper filling port 5 is filled with porcelain balls, and the upper filling port 5 is sealed; when the lower desulfurization chamber 6 is filled with desulfurizer, the device is placed upside down, the lower filling port 4 is opened, and the desulfurizer is filled into the lower desulfurization chamber 6 through the lower filling port 4. When the height of the desulfurizer is slightly higher than the bottom of the lower filling port 4, the lower filling port 4 is filled with porcelain balls, and the lower filling port 4 is sealed;

[0031] When the desulfurizer is removed from the lower desulfurization chamber 6, the device is placed upright, the lower filling port 4 is opened, and the stirring rod is passed through the lower filling port 4 into the lower desulfurization chamber 6 to ensure that the desulfurizer can be completely removed from the lower desulfurization chamber 6; when the desulfurizer is removed from the upper desulfurization chamber 8, the device is placed inverted, the upper filling port 5 is opened, and the stirring rod is passed through the upper filling port 5 into the upper desulfurization chamber 8 to ensure that the desulfurizer can be completely removed from the upper desulfurization chamber 8.

[0032] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0033] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A natural gas desulfurization device for a solid oxide fuel cell, comprising a tank body (1), characterized in that: The interior of the tank body (1) is provided with a lower desulfurization chamber lower sieve plate (9), a lower desulfurization chamber (6), a lower desulfurization chamber upper sieve plate (10), a gas buffer zone (7), an upper desulfurization chamber lower sieve plate (11), an upper desulfurization chamber (8), and an upper desulfurization chamber upper sieve plate (12) from bottom to top, respectively; the bottom of the tank body (1) is connected to a lower filling port (4), the top of the tank body (1) is connected to an upper filling port (5), the bottom of the side of the tank body (1) and located at the bottom of the lower desulfurization chamber lower sieve plate (9) is connected to and penetrated by an air inlet (2), and the top of the side of the tank body (1) and located at the top of the upper desulfurization chamber upper sieve plate (12) is connected to and penetrated by an air outlet (3).

2. A natural gas desulfurization device for solid oxide fuel cells according to claim 1, characterized in that: The lower desulfurization chamber (6) and the upper desulfurization chamber (8) are respectively filled with desulfurizing agents of two different specifications.

3. A natural gas desulfurization device for solid oxide fuel cells according to claim 1, characterized in that: The lower desulfurization chamber (6) and the upper desulfurization chamber (8) are independently loaded and removed with desulfurizing agent through the upper filling port (5) and the lower filling port (4) respectively.

4. A natural gas desulfurization device for a solid oxide fuel cell according to claim 1, characterized in that: The packing ends of the lower filling port (4) and the upper filling port (5) are both detachably mounted with flanges (14) via bolts (13).

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