Protective gas supply device for stainless steel production

Abstract

The invention discloses a protective gas supply device for stainless steel production. The protective gas supply device comprises a device main body, the ammonia decomposition furnace is connected with an ammonia gas inlet pipe and a first generated gas discharge pipe; the ammonia combustion furnace is connected with a mixed gas inlet pipe and a second generated gas discharge pipe, and the second generated gas discharge pipe is partially wound on the ammonia gas inlet pipe; the filter is arranged at the outlet end of the second generated gas discharge pipe; the gas separator is used for collecting gas exhausted from the gas exhaust pipe and separating hydrogen and nitrogen, and a hydrogen outlet pipe and a nitrogen outlet pipe which are communicated with the gas collection cavity are arranged on the gas separator; the heat conduction device is connected with the ammonia decomposition furnace and the ammonia combustion furnace. The protective gas supply device for stainless steel production can solve the problems that an existing protective gas supply device for stainless steel production is high in cost, low in heat conduction and utilization rate and slow in gas temperature rise, so that the protective gas generation rate is slow, the production gas supply mode is single, and the production efficiency is low.

Description

Technical Field

[0001] The invention relates to the technical field of stainless steel production equipment, in particular to a protective gas supply device used for stainless steel production. Background Art

[0002] During stainless steel production, it is generally necessary to use a pickling process to clean the surface oxide layer and impurities of the stainless steel, which aggravates the hydrogen embrittlement problem of stainless steel products. At present, the annealing process of stainless steel uses a bright annealing furnace, which introduces protective gas into the interior during the annealing process of stainless steel to avoid oxidation of the stainless steel surface and ensure surface brightness. In this way, the subsequent pickling process is omitted, ensuring efficient processing and stable product quality.

[0003] Nowadays, most protective gases are hydrogen, and the gas supply device uses ammonia decomposition to produce hydrogen, which needs to be carried out at high temperatures. Its heat source is generally electric heating or fuel combustion. When electric heating is used as a heat source, the cost of hydrogen production is relatively high. When fuel combustion is used for heating, the heat conduction and utilization rate are low, and the gas temperature rises slowly, which makes the protective gas generation rate slow. In addition, the production gas supply method is single, resulting in low production efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a protective gas supply device for stainless steel production in order to solve the problems that the current protective gas supply device for stainless steel production has high cost, low heat conduction and utilization rate, slow gas heating, resulting in slow protective gas generation rate, and a single production gas supply method, resulting in low production efficiency.

[0005] In order to achieve the above object, the present invention adopts the following technical solution: a protective gas supply device for stainless steel production, comprising:

[0006] a device body, which is provided with an inner cavity;

[0007] an ammonia decomposition furnace, to which an ammonia gas inlet pipe and a first generated gas outlet pipe are respectively connected;

[0008] an ammonia combustion furnace, to which a mixed gas inlet pipe for inputting a mixed gas consisting of ammonia and a combustion-supporting gas and a second generated gas outlet pipe are respectively connected, wherein the second generated gas outlet pipe is partially wound around the ammonia inlet pipe;

[0009] A filter, which is arranged at the outlet end of the second generated gas exhaust pipe;

[0010] A gas separator, which is fixed to the bottom of the inner cavity through a base, and is used to collect the gas discharged from the first generated gas discharge pipe and the second generated gas discharge pipe and to separate hydrogen and nitrogen. A hydrogen outlet pipe and a nitrogen outlet pipe connected to the gas collecting cavity are arranged on the gas separator;

[0011] A heat conducting device is connected to the ammonia decomposition furnace and the ammonia combustion furnace.

[0012] As a further description of the above technical solution:

[0013] A plurality of ammonia inlet pipes are provided and extend upward from the bottom of the inner cavity to be connected to the side of the ammonia decomposition furnace. The first generated gas exhaust pipe is provided at the bottom of the ammonia decomposition furnace.

[0014] As a further description of the above technical solution:

[0015] The mixed gas inlet pipe is arranged on the top of the ammonia combustion furnace, the second generated gas exhaust pipe extends downward from the side of the ammonia combustion furnace and a spiral pipe section is sleeved on the vertical extension section of the ammonia inlet pipe.

[0016] As a further description of the above technical solution:

[0017] A support is arranged in the inner cavity, and the support is used to sleeve, support and position the second generated gas discharge pipe and the spiral pipe section through a positioning piece.

[0018] As a further description of the above technical solution:

[0019] A foreign matter discharge pipe extends from the bottom of the filter.

[0020] As a further description of the above technical solution:

[0021] The outlet end of the first generated gas exhaust pipe is connected to the first inlet of the gas separator, and the nitrogen exhaust port on the filter is connected to the second inlet of the gas separator. The sizes of the first inlet, the second inlet and the inner ends of the hydrogen outlet pipe and the nitrogen outlet pipe gradually increase along the direction of the air flow.

[0022] As a further description of the above technical solution:

[0023] The nitrogen outlet pipe is located at the bottom of the gas separator, the hydrogen outlet pipe is located at the side of the gas separator, and the gas collecting cavity is provided with a molecular sieve inclined downward inside the air duct corresponding to the hydrogen outlet pipe.

[0024] As a further description of the above technical solution:

[0025] The heat conducting device is a copper heat conducting fin assembly.

[0026] In summary, due to the adoption of the above technical solution, the present invention has the following beneficial effects compared with the prior art:

[0027] The present invention is equipped with an ammonia combustion furnace to perform auxiliary heating of ammonia in the ammonia decomposition furnace and preheating of intake air, thereby ensuring sufficient decomposition of ammonia. At the same time, nitrogen generated by the ammonia combustion furnace is purified and impurities are removed through a filter, and then merged with the generated gas of the ammonia decomposition furnace into a gas separator. The gas for venting the reaction furnace and the gas transmission pipeline and the protective gas are separated, discharged and stored through a molecular sieve, so that the ammonia combustion furnace in the gas supply device can simultaneously realize heating of the ammonia decomposition furnace, preheating of intake air, and discharge of air and waste gas in the pipeline and supply of gas for venting; and through the efficient cross-transmission of the inlet and outlet gases of the ammonia decomposition furnace and the ammonia combustion furnace, sufficient preheating of the intake air of the ammonia decomposition furnace is achieved while reducing the size of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0029] Figure 1 It is a cross-sectional view of a protective gas supply device used in stainless steel production.

[0030] Figure 2 The present invention is a cross-sectional view of a gas separator in a protective gas supply device used in stainless steel production.

[0031] Legend:

[0032] 1. Device body; 11. Inner cavity; 12. Bracket; 121. Positioning piece; 13. Base; 2. Ammonia decomposition furnace; 21. Ammonia inlet pipe; 22. First generated gas outlet pipe; 3. Ammonia combustion furnace; 31. Mixed gas inlet pipe; 32. Second generated gas outlet pipe; 33. Spiral pipe section; 4. Filter; 41. Impurity outlet pipe; 5. Gas separator; 50. Gas collecting cavity; 51. First inlet; 52. Second inlet; 53. Molecular sieve; 54. Hydrogen outlet pipe; 55. Nitrogen outlet pipe; 6. Heat transfer device. DETAILED DESCRIPTION

[0033] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] In the description of the present invention, it is necessary to understand that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are 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 cannot be understood as a limitation on the present invention.

[0035] See also Figure 1-2 The present invention provides a technical solution: a protective gas supply device for stainless steel production, comprising:

[0036] The device body 1 is provided with an inner cavity 11;

[0037] an ammonia decomposition furnace 2, to which an ammonia gas inlet pipe 21 and a first generated gas outlet pipe 22 are respectively connected;

[0038] The ammonia combustion furnace 3 is connected with a mixed gas inlet pipe 31 for inputting a mixed gas composed of ammonia and a combustion-supporting gas and a second generated gas outlet pipe 32, and the second generated gas outlet pipe 32 is partially wound around the ammonia inlet pipe 21; in this embodiment, a catalyst layer is arranged in the ammonia combustion furnace 3, wherein ammonia is catalytically combusted, and the heat released is used to assist in heating the ammonia decomposition furnace 2, thereby reducing energy consumption, and the combustion-supporting gas is oxygen or air to ensure sufficient combustion;

[0039] The filter 4 is arranged at the outlet end of the second generated gas exhaust pipe 32; in this embodiment, the filter 4 filters and retains impurities such as water in the generated gas of the catalytic combustion reaction in the ammonia combustion furnace 3, so that the outlet end thereof outputs pure nitrogen, so that the ammonia combustion furnace 3 in the gas supply device can simultaneously realize the heating of the ammonia decomposition furnace 2 and the discharge of air and exhaust gas in the pipeline and the supply of gas for venting.

[0040] The gas separator 5 is fixed to the bottom of the inner cavity 11 through the base 13, and is used to collect the gas discharged from the first generated gas discharge pipe 22 and the second generated gas discharge pipe 32 and to separate hydrogen and nitrogen. A hydrogen outlet pipe 54 and a nitrogen outlet pipe 55 connected to the gas collecting cavity 50 are arranged on the gas separator 5;

[0041] The heat conducting device 6 is connected to the ammonia decomposition furnace 2 and the ammonia combustion furnace 3 to achieve efficient heat transfer and auxiliary heat supply for the ammonia decomposition furnace 2 .

[0042] A plurality of ammonia gas inlet pipes 21 are provided and extend upward from the bottom of the inner cavity 11 to be connected to the side of the ammonia decomposition furnace 2 . The first generated gas exhaust pipe 22 is provided at the bottom of the ammonia decomposition furnace 2 .

[0043] The mixed gas inlet pipe 31 is arranged at the top of the ammonia combustion furnace 3, and the second generated gas exhaust pipe 32 extends downward from the side of the ammonia combustion furnace 3 and is sleeved with a spiral pipe section 33 on the vertical extension section of the ammonia inlet pipe 21. Thus, through the efficient cross-transmission of the inlet and outlet gases of the ammonia decomposition furnace 2 and the ammonia combustion furnace 3, sufficient inlet preheating of the ammonia decomposition furnace 2 is achieved while reducing the size of the device.

[0044] A support 12 is provided in the inner cavity 11, and the support 12 is used to sleeve and support the second generated gas discharge pipe 32 and the spiral pipe section 33 through a positioning member 121, thereby improving the positioning stability of the gas delivery pipeline and ensuring the sealing of the pipeline interface.

[0045] An impurity discharge pipe 41 extends from the bottom of the filter 4, and impurities such as water trapped by the filter 4 are discharged.

[0046] The outlet end of the first generated gas exhaust pipe 22 is connected to the first inlet 51 of the gas separator 5, and the nitrogen exhaust port on the filter 4 is connected to the second inlet 52 of the gas separator 5. The sizes of the first inlet 51, the second inlet 52 and the inner ends of the hydrogen outlet pipe 54 and the nitrogen outlet pipe 55 gradually increase with the direction of the air flow, thereby improving the transportation efficiency of nitrogen and hydrogen.

[0047] The nitrogen outlet pipe 55 is located at the bottom of the gas separator 5, the hydrogen outlet pipe 54 is located at the side of the gas separator 5, and the gas collecting cavity 50 is provided with a molecular sieve 53 inclined downward on the inner side of the air duct corresponding to the hydrogen outlet pipe 54 to achieve efficient separation of nitrogen and hydrogen.

[0048] The heat conducting device 6 is a copper heat conducting fin assembly, which further improves the heat transfer efficiency between the two furnaces.

[0049] The working principle of the protective gas supply device for stainless steel production in this embodiment includes: when in use, the reaction gas of the ammonia combustion furnace 3 is first introduced through the mixed gas inlet pipe 31, and the internal gas is catalytically burned through the internal high temperature, and the generated nitrogen, water and other impurities are transported downward along the second generated gas discharge pipe 32, and the ammonia introduced into the ammonia inlet pipe 21 is preheated and transported to the ammonia decomposition furnace 2 of the protective gas main generator, and the heat conducted by the ammonia combustion furnace 3 through the heat conduction device 6 is used to decompose the ammonia. The generated nitrogen and hydrogen are transported to the gas separator 5 by the first generated gas discharge pipe 22. The gas in the second generated gas discharge pipe 32 is intercepted by the water, residual ammonia and other impurities of the filter 4 and discharged through the impurity discharge pipe 41 and the nitrogen filtering and discharging function, and is further transported to the gas separator 5. Among them, the hydrogen in the two merged air flows passes through the 5A molecular sieve and is transported to the hydrogen supply pipeline and the hydrogen bottle by the hydrogen outlet pipe 54. The nitrogen is blocked by the molecular sieve 53 and is transported to the nitrogen supply pipeline and the nitrogen bottle by the nitrogen outlet pipe 55. When annealing stainless steel products in the bright annealing furnace, nitrogen is introduced to discharge the internal air, and then hydrogen is introduced to the internal to perform anti-oxidation treatment of stainless steel during stainless steel annealing production, so that subsequent stainless steel does not need to be pickled, reducing the hydrogen embrittlement problem of subsequent stainless steel products; after processing, nitrogen is introduced to discharge internal waste gas.

[0050] In summary, due to the adoption of the above technical solution, the protective gas supply device for stainless steel production in this embodiment has the following beneficial effects compared with the prior art:

[0051] The present invention is equipped with an ammonia combustion furnace to perform auxiliary heating of ammonia in the ammonia decomposition furnace and preheating of intake air, thereby ensuring sufficient decomposition of ammonia. At the same time, nitrogen generated by the ammonia combustion furnace is purified and impurities are removed through a filter, and then merged with the generated gas of the ammonia decomposition furnace into a gas separator. The gas for venting the reaction furnace and the gas transmission pipeline and the protective gas are separated, discharged and stored through a molecular sieve, so that the ammonia combustion furnace in the gas supply device can simultaneously realize heating of the ammonia decomposition furnace, preheating of intake air, and discharge of air and waste gas in the pipeline and supply of gas for venting; and through the efficient cross-transmission of the inlet and outlet gases of the ammonia decomposition furnace and the ammonia combustion furnace, sufficient preheating of the intake air of the ammonia decomposition furnace is achieved while reducing the size of the device.

[0052] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A protective gas supply device for stainless steel production, characterized in that: include: a device body, which is provided with an inner cavity; an ammonia decomposition furnace, to which an ammonia gas inlet pipe and a first generated gas discharge pipe are respectively connected; an ammonia combustion furnace, to which a mixed gas inlet pipe for inputting a mixed gas consisting of ammonia and a combustion-supporting gas and a second generated gas outlet pipe are respectively connected, wherein the second generated gas outlet pipe is partially wound around the ammonia inlet pipe; A filter, which is arranged at the outlet end of the second generated gas exhaust pipe; A gas separator, which is fixed to the bottom of the inner cavity through a base, and is used to collect the gas discharged from the first generated gas discharge pipe and the second generated gas discharge pipe and to separate hydrogen and nitrogen. A hydrogen outlet pipe and a nitrogen outlet pipe connected to the gas collecting cavity are arranged on the gas separator; A heat conducting device is connected to the ammonia decomposition furnace and the ammonia combustion furnace.

2. A protective gas supply device for stainless steel production according to claim 1, characterized in that: A plurality of ammonia gas inlet pipes are provided and extend upward from the bottom of the inner cavity to be connected to the side of the ammonia decomposition furnace. The first generated gas exhaust pipe is provided at the bottom of the ammonia decomposition furnace.

3. The protective gas supply device for stainless steel production according to claim 1, characterized in that: The mixed gas inlet pipe is arranged on the top of the ammonia combustion furnace, the second generated gas exhaust pipe extends downward from the side of the ammonia combustion furnace and a spiral pipe section is sleeved on the vertical extension section of the ammonia inlet pipe.

4. The protective gas supply device for stainless steel production according to claim 3, characterized in that: A support is arranged in the inner cavity, and the support is used to sleeve, support and position the second generated gas discharge pipe and the spiral pipe section through a positioning piece.

5. The protective gas supply device for stainless steel production according to claim 1, characterized in that: A foreign matter discharge pipe extends from the bottom of the filter.

6. The protective gas supply device for stainless steel production according to claim 1, characterized in that: The outlet end of the first generated gas exhaust pipe is connected to the first inlet of the gas separator, and the nitrogen exhaust port on the filter is connected to the second inlet of the gas separator. The sizes of the first inlet, the second inlet and the inner ends of the hydrogen outlet pipe and the nitrogen outlet pipe gradually increase along the direction of the air flow.

7. The protective gas supply device for stainless steel production according to claim 1, characterized in that: The nitrogen outlet pipe is located at the bottom of the gas separator, the hydrogen outlet pipe is located at the side of the gas separator, and the gas collecting cavity is provided with a molecular sieve inclined downward on the inner side of the air duct corresponding to the hydrogen outlet pipe.

8. The protective gas supply device for stainless steel production according to claim 1, characterized in that: The heat conducting device is a copper heat conducting fin assembly.

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