Device for prolonging service life of ammonia decomposition furnace core in glass production
By adding sleeves and baffles to the ammonia inlet tubes and distributors of the ammonia decomposition furnace core, the safety hazards and production losses caused by corrosion leakage of the ammonia decomposition furnace core are solved, extending the service life and reducing maintenance costs.
Patent Information
- Application Number
- CN202421519000.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-06-28
- Publication Date
- 2025-05-09
- Estimated Expiration
- 2034-06-28
AI Technical Summary
After two years of use, the existing ammonia decomposition furnace core has caused ammonia leakage and fire due to high-temperature ammonia corrosion, carbonization, burning, etc., resulting in frequent furnace shutdown and maintenance and production losses.
A device including an ammonia inlet tube, an ammonia inlet distributor and a reaction tube is designed. By adding a sleeve to the ammonia inlet tube and adding an upper and lower baffle to the ammonia inlet distributor, high-temperature ammonia gas is prevented from directly impacting the lower seal head and reducing corrosion and wear.
The service life of the ammonia inlet tube and distributor is extended, and the need for mid-way replacement is avoided, ensuring that the service life of the decomposition furnace core reaches or is close to the service life of nickel catalyst is reduced, and production costs and maintenance labor is reduced.
Smart Images
Figure CN222846456U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to a device for prolonging the service life of an ammonia decomposition furnace core in glass production. Background Art
[0002] Ammonia decomposition for glass production uses liquid ammonia as raw material. Under the action of a catalyst, it is heated and decomposed to obtain a hydrogen-nitrogen mixed gas containing 75% hydrogen and 25% nitrogen. Under normal process conditions, the pressure is ≤0.2MPa, the temperature is 790-830 degrees, the raw material ammonia oil content is ≤2mg / kg, and there is basically no impurities and moisture. Ammonia is a highly corrosive and irritating gas, especially high-temperature ammonia has extremely strong corrosiveness. Ordinary carbon steel and stainless steel cannot be used normally in a high-temperature ammonia environment. At present, only 310S (new national standard S31008--06Cr25Ni20) and 316L (new national standard S31603--022Cr17Ni12Mo2) can basically meet the use requirements. The main material of the ammonia decomposition furnace is 310S. 310S has good high temperature resistance. When the temperature exceeds 800 degrees, it begins to soften, and the allowable stress begins to continuously decrease. The use temperature can reach 1200 degrees. Due to the high nickel-chromium content, it has good oxidation resistance, corrosion resistance, acid and alkali resistance, and high temperature resistance, and is often used as a material for manufacturing electric heating furnaces. The ammonia decomposition furnace core has very high requirements for the selection of stainless steel pipes, which must be both corrosion-resistant and high-temperature-resistant. Therefore, the design requires that the main body must use 310S stainless steel pipes. If other materials are used, it is very easy to cause the ammonia decomposition intake pipe part, especially the high and low temperature combined parts, to corrode, carbonize, burn and break, causing a large amount of liquid ammonia leakage. Under high temperature conditions, ammonia gas leakage in the ammonia decomposition furnace will catch fire.
[0003] like Figure 1 As shown, the normal service life of the nickel catalyst 1' filled in the core of the ammonia decomposition furnace is 3 to 5 years. However, after the decomposition furnace core has been used for 2 years, the ammonia inlet pipe 2' and the bottom cover 4' of the ammonia inlet distributor 3' often occur due to corrosion, carbonization, burning and other phenomena of high-temperature ammonia, resulting in ammonia leakage and fire. The current response measures are to replace the furnace core ammonia inlet pipe every two years and scrap the decomposition furnace core after four years. The actual use time of the decomposition furnace core has not reached the normal service life of the catalyst, resulting in a 2-year shutdown for maintenance and replacement of the ammonia inlet pipe and distributor, causing losses to production. Utility Model Content
[0004] The purpose of the utility model is to overcome the deficiencies of the prior art and provide a device for extending the service life of an ammonia decomposition furnace core in glass production, thereby avoiding potential safety hazards caused by corrosion and leakage of an ammonia inlet pipe and a distributor, and at the same time eliminating the shutdown of the furnace for maintenance caused by corrosion and leakage of an ammonia inlet pipe and a distributor of the decomposition furnace core, thereby reducing production losses.
[0005] The technical solution adopted by the utility model to solve its technical problems is:
[0006] A device for extending the service life of an ammonia decomposition furnace core in glass production comprises an ammonia inlet pipe, an ammonia inlet distributor and a reaction tube, wherein the ammonia inlet distributor is a sac-like structure composed of an upper head and a lower head, the bottom of the ammonia inlet pipe is inserted into the upper head and connected to the ammonia inlet distributor, at least two layers of sleeves are tightly wrapped outside the lower part of the ammonia inlet pipe, there are multiple reaction tubes, and the multiple reaction tubes are respectively connected to the ammonia inlet distributor through connecting pipes, an upper baffle is provided in the upper head of the ammonia inlet distributor below the port of the ammonia inlet pipe, and the high-temperature ammonia gas sprayed from the port of the ammonia inlet pipe enters the ammonia inlet distributor from the side of the upper baffle after being guided by the upper baffle, and flows into the reaction tube through the connecting pipe, and the reaction tube is filled with a nickel catalyst; a lower baffle is provided in the lower head of the ammonia inlet distributor, and the peripheral edge of the lower baffle is welded to the lower head.
[0007] In another preferred embodiment, the upper baffle includes two side plates and a bottom plate, and the tops of the two side plates are welded in the upper head of the ammonia inlet distributor.
[0008] In another preferred embodiment, a sealed insulating layer is formed between the lower baffle and the lower head of the ammonia inlet distributor.
[0009] In another preferred embodiment, the connecting tube is arranged at the lower part of the reaction tube, a perforated baffle is provided above the connection between the connecting tube and the reaction tube in the reaction tube, and the nickel catalyst is filled above the perforated baffle and at the bottom of the reaction tube.
[0010] In another preferred embodiment, the lower part of the ammonia inlet pipe is tightly wrapped with two layers of casing, the bottom of the inner casing is inserted into the ammonia inlet pipe distributor, and the bottom of the outer casing is welded to the outer wall of the ammonia inlet distributor.
[0011] In another preferred embodiment, the thickness of the upper head and the lower head of the ammonia inlet distributor is 8 mm.
[0012] The beneficial effect of the utility model is that a sleeve is added to the ammonia inlet pipe to extend its service life and avoid the need to replace the ammonia inlet pipe midway. By adding a baffle in the ammonia inlet distributor, high-temperature ammonia is prevented from directly impacting the lower head, the corrosion and wear rate of the head is slowed down, and its service life is extended to reach or approach the service life of the nickel catalyst, without the need for midway maintenance, which greatly saves production costs and the maintenance labor of production employees.
[0013] The utility model is further described in detail below in conjunction with the accompanying drawings and embodiments; however, the utility model is not limited to the embodiment as a device for extending the service life of an ammonia decomposition furnace core in glass production. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1It is a structural schematic diagram of an existing ammonia decomposition furnace core.
[0015] Figure 2 It is a structural schematic diagram of an ammonia decomposition furnace core of a preferred embodiment of the utility model.
[0016] Figure 3 It is a structural schematic diagram of an upper baffle of an ammonia decomposition furnace core according to a preferred embodiment of the utility model.
[0017] Figure 4 It is a structural schematic diagram of a lower baffle of an ammonia decomposition furnace core according to a preferred embodiment of the utility model. DETAILED DESCRIPTION
[0018] For example, see Figures 2 to 4 As shown, a device for extending the service life of an ammonia decomposition furnace core in glass production of the utility model comprises an ammonia inlet pipe 1, an ammonia inlet distributor 2 and a reaction tube 3, wherein the ammonia inlet distributor 2 is a sac-like structure composed of an upper head 21 and a lower head 22, the bottom of the ammonia inlet pipe 1 is inserted into the upper head 21 and connected to the ammonia inlet distributor 2, the lower part of the ammonia inlet pipe 1 is tightly wrapped with two layers of sleeves 4, the bottom of the inner sleeve is inserted into the ammonia inlet pipe distributor, and the bottom of the outer sleeve is welded to the outer wall of the ammonia inlet distributor 2. There are multiple reaction tubes 3, and the multiple reaction tubes 3 are connected to the ammonia inlet distributor 2 through connecting pipes 5 respectively. An upper baffle 6 is provided in the upper head 21 of the ammonia inlet distributor 2 below the port of the ammonia inlet pipe 1. The high-temperature ammonia gas sprayed from the port of the ammonia inlet pipe 1 enters the ammonia inlet distributor 2 from the side of the upper baffle 6 after being guided by the upper baffle 6, and flows into the reaction tube 3 through the connecting pipe 5. The reaction tube 3 is filled with a nickel catalyst 7; a lower baffle 8 is provided in the lower head 22 of the ammonia inlet distributor 2, and the periphery of the lower baffle 8 is welded to the lower head 22.
[0019] like Figure 3 As shown, the upper baffle plate 6 includes two side plates and a bottom plate, and the tops of the two side plates are welded inside the upper head 21 of the ammonia inlet distributor 2.
[0020] like Figure 4 As shown, the lower baffle plate 8 is a circular structure, and a sealing insulation layer is formed between the lower baffle plate 8 and the lower head 22 of the ammonia inlet distributor 2.
[0021] The connecting tube 5 is arranged at the lower part of the reaction tube 3 . A perforated baffle is arranged above the connection between the connecting tube 5 and the reaction tube 3 in the reaction tube 3 . The nickel catalyst 7 is filled above the perforated baffle and at the bottom of the reaction tube 3 .
[0022] The thickness of the upper and lower heads of the ammonia inlet distributor is changed from 6mm to 8mm, and they are made of 310S material. The thickness of the upper baffle 6 and the lower baffle 8 is also 8mm, and they are made of 316L stainless steel material.
[0023] After the ammonia inlet pipe of this embodiment is changed into a three-layer sleeve, its service life is extended and is expected to reach 3 to 5 years, that is, the ammonia inlet pipe does not need to be replaced midway during the service life of the furnace core catalyst;
[0024] The thickness of the upper and lower heads and the tube wall of the ammonia distributor is increased from 6mm to 8mm, and the material is 316L stainless steel. At the same time, two 8mm baffles are added at the upper and lower parts, and the material is 316L stainless steel. Its service life is expected to reach 3 to 5 years, which meets the requirements of one service life of the catalyst.
[0025] In the actual use of the above embodiment, 9 decomposition furnaces had to be shut down for 2 years to replace the ammonia inlet pipes before the transformation. However, some decomposition furnaces had ammonia inlet pipes that were corroded, leaked and caught fire in less than 2 years (see Table 1):
[0026] Table 1
[0027]
[0028] After the transformation, the decomposition furnace of this embodiment was used and the whole furnace core was replaced after 4 years of operation, and no corrosion, leakage or fire occurred (see Table 2 for details).
[0029] Table 2
[0030]
[0031]
[0032] Therefore, the reconstruction device for extending the service life of the decomposition furnace core in this embodiment has indeed increased the corrosion resistance of the ammonia inlet pipe and the distributor, and extended the service life of the decomposition furnace core by 2 to 3 years, without the need for mid-term maintenance. The potential safety hazards caused by corrosion and leakage of the ammonia inlet pipe and the distributor are avoided, and the shutdown maintenance caused by corrosion and leakage of the ammonia inlet pipe and the distributor of the decomposition furnace core is eliminated, which greatly saves production costs and the maintenance labor of production employees.
[0033] The above embodiments are only used to further illustrate a device for extending the service life of an ammonia decomposition furnace core in glass production of the utility model, but the utility model is not limited to the embodiments. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the utility model fall within the protection scope of the technical solution of the utility model.
Claims
1. A device for extending the service life of an ammonia decomposition furnace core in glass production, characterized in that: It comprises an ammonia inlet pipe, an ammonia inlet distributor and a reaction tube. The ammonia inlet distributor is a sac-like structure composed of an upper end cap and a lower end cap. The bottom of the ammonia inlet pipe is inserted into the upper end cap and connected to the ammonia inlet distributor. The lower part of the ammonia inlet pipe is tightly wrapped with at least two layers of sleeves. There are multiple reaction tubes, and the multiple reaction tubes are respectively connected to the ammonia inlet distributor through connecting tubes. An upper baffle is provided in the upper end cap of the ammonia inlet distributor below the port of the ammonia inlet pipe. The high-temperature ammonia gas sprayed from the port of the ammonia inlet pipe enters the ammonia inlet distributor from the side of the upper baffle after being guided by the upper baffle, and flows into the reaction tube through the connecting tube. The reaction tube is filled with nickel catalyst; a lower baffle is arranged in the lower end cover of the ammonia inlet distributor, and the periphery of the lower baffle is welded to the lower end cover.
2. The device for extending the service life of ammonia decomposition furnace core in glass production according to claim 1, characterized in that: The upper baffle plate includes two side plates and a bottom plate, and the tops of the two side plates are welded in the upper head of the ammonia inlet distributor.
3. The device for extending the service life of ammonia decomposition furnace core in glass production according to claim 1, characterized in that: A sealing insulation layer is formed between the lower baffle and the lower head of the ammonia inlet distributor.
4. The device for extending the service life of ammonia decomposition furnace core in glass production according to claim 1, characterized in that: The connecting tube is arranged at the lower part of the reaction tube, a perforated baffle is arranged above the connection between the connecting tube and the reaction tube in the reaction tube, and the nickel catalyst is filled above the perforated baffle and at the bottom of the reaction tube.
5. The device for extending the service life of ammonia decomposition furnace core in glass production according to claim 1, characterized in that: The lower part of the ammonia inlet pipe is tightly wrapped with two layers of sleeves, the bottom of the inner sleeve is inserted into the ammonia inlet pipe distributor, and the bottom of the outer sleeve is welded to the outer wall of the ammonia inlet distributor.
6. The device for extending the service life of ammonia decomposition furnace core in glass production according to claim 1, characterized in that: The thickness of the upper and lower heads of the ammonia inlet distributor is 8 mm.