Nitrogen and hydrogen gas recovery system for silicon steel

Abstract

The nitrogen and hydrogen gas recovery system comprises a silicon steel heat treatment line annealing furnace, a waste gas discharge and recovery mechanism and a protective gas distribution mechanism, a waste gas discharge port is formed in the top of the silicon steel heat treatment line annealing furnace, and the waste gas discharge port communicates with a waste gas discharge pipe and a port in one end of a first diffusion branch pipe; a port at the other end of the waste gas recovery pipe is communicated with a protective gas inlet of the silicon steel heat treatment line annealing furnace, a waste gas emission recovery mechanism and a protective gas distribution mechanism are sequentially arranged on the waste gas recovery pipe, and the nitrogen and hydrogen gas in the annealing furnace can be recovered and reused, so that the pollution to the surrounding environment is reduced, and the use amount of hydrogen gas is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of strip steel heat treatment furnaces, and in particular relates to a nitrogen and hydrogen gas recovery system for silicon steel. Background Art

[0002] In the existing production process of silicon steel heat treatment lines, a certain amount of hydrogen-containing waste gas will be generated due to process requirements. The method for treating this part of hydrogen-containing waste gas in silicon steel heat treatment lines has always been to ignite this part of hydrogen-containing waste gas through an ignition burner, and then discharge the burned waste gas out of the factory through the chimney or directly discharge it into the factory.

[0003] At present, with the improvement of silicon steel product quality requirements, more and more silicon steel units use high hydrogen atmosphere, and the hydrogen consumption of the units also increases. If the above method is still used to treat hydrogen-containing waste gas, it will not only pollute the surrounding environment, but also increase the cost of the product in disguise because of the increase in the one-time consumption of hydrogen. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a nitrogen-hydrogen gas recovery system for silicon steel in view of the above-mentioned existing problems, so as to reuse the hydrogen to save resources and reduce the pollution to the environment.

[0005] The technical solution adopted by the present invention to solve the above technical problems is: a nitrogen-hydrogen gas recovery system for silicon steel, characterized in that it includes an annealing furnace of a silicon steel heat treatment line, a waste gas emission recovery mechanism and a protective gas distribution mechanism, a waste gas emission port is provided on the top of the annealing furnace of the silicon steel heat treatment line, the waste gas emission port is respectively connected to a waste gas recovery pipe and one end port of a first venting branch pipe, the other end port of the waste gas recovery pipe is connected to the protective gas inlet of the annealing furnace of the silicon steel heat treatment line, and the waste gas emission recovery mechanism and the protective gas distribution mechanism are sequentially provided on the waste gas recovery pipe.

[0006] According to the above solution, a second venting branch pipe is provided on the waste gas recovery pipe at a position between the waste gas emission recovery mechanism and the protective gas distribution mechanism.

[0007] According to the above scheme, the exhaust gas emission recovery mechanism includes a high-temperature heat exchanger, a filter and an online gas analyzer, and the exhaust gas is subjected to gas composition analysis after heat exchange cooling and filtration purification.

[0008] According to the above scheme, the protective gas distribution mechanism includes a gas mixer, a hydrogen distribution system and a nitrogen distribution system, and the hydrogen distribution system and the nitrogen distribution system are respectively connected to the hydrogen inlet and the nitrogen inlet on the gas mixer.

[0009] According to the above solution, the first relief branch pipe and the second relief branch pipe are respectively provided with a first relief valve and a second relief valve.

[0010] According to the above scheme, the exhaust gas recovery pipe is respectively provided with a first shut-off valve and a second shut-off valve at the inlet and outlet of the exhaust gas emission recovery mechanism.

[0011] According to the above solution, a third shut-off valve is provided at a position of the waste gas recovery pipe between the second venting branch pipe and the protective gas distribution mechanism.

[0012] The beneficial effects of the present invention are as follows: a nitrogen and hydrogen gas recovery system for silicon steel is provided, which realizes the purification of nitrogen and hydrogen gases in the annealing furnace of a silicon steel heat treatment line, and the gas that is re-proportioned to meet the demand of the annealing furnace re-enters the annealing furnace of the silicon steel heat treatment line for continued recycling, thereby avoiding direct combustion and emission of waste gas from the silicon steel heat treatment annealing furnace, reducing pollution to the surrounding environment, reducing the use of hydrogen, greatly saving energy consumption, and playing a positive role in energy conservation, emission reduction, cost reduction and efficiency improvement for enterprises. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 A simplified system diagram of an embodiment of the present invention;

[0014] Figure 2 The figure is a simplified system diagram of a protective gas distribution mechanism according to an embodiment of the present invention. DETAILED DESCRIPTION

[0015] In order to better understand the present invention, the present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0016] It should be noted that in the description of the present invention, the terms "transverse", "longitudinal", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply 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 limiting the present invention. In addition, the terms "first", "second" and the like are only used for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0017] like Figure 1-Figure 2As shown, a nitrogen and hydrogen gas recovery system for silicon steel includes an annealing furnace 1 for a heat treatment line of silicon steel, an exhaust gas emission recovery mechanism 2 and a protective gas distribution mechanism 3. An exhaust gas emission port 4 is provided on the top of the annealing furnace for the heat treatment line of silicon steel, and the exhaust gas emission port is connected to an exhaust gas recovery pipe 5 and one end of a first venting branch pipe 6 respectively. The other end of the exhaust gas recovery pipe is connected to the protective gas inlet of the annealing furnace for the heat treatment line of silicon steel. An exhaust gas emission recovery mechanism and a protective gas distribution mechanism are provided on the exhaust gas recovery pipe in sequence. By setting up an exhaust gas recovery pipeline, the nitrogen and hydrogen exhaust gas in the annealing furnace of the heat treatment line of silicon steel is purified, and the ratio is adjusted according to the process requirements for recycling, which reduces pollution to the surrounding environment, reduces the amount of hydrogen used, and greatly saves energy consumption.

[0018] A second venting branch pipe 7 is provided on the waste gas recovery pipe between the waste gas emission recovery mechanism and the protective gas distribution mechanism, and the purified gas can be directly vented and discharged through the second venting branch pipe.

[0019] The exhaust gas recovery mechanism includes a high-temperature heat exchanger, a filter and an online gas analyzer. After the exhaust gas is cooled by heat exchange and purified by filtration, the gas composition is analyzed. The above-mentioned exhaust gas recovery mechanism can also be equipped with a boosting system for gas boosting treatment, and can also be equipped with deoxygenation equipment, cooling and condensing equipment, drying and purification equipment, etc., to perform multiple processing steps in sequence to obtain high-purity gas, and finally perform gas composition analysis.

[0020] The protective gas distribution mechanism includes a gas mixer 8, a hydrogen distribution system 9 and a nitrogen distribution system 10, and the hydrogen distribution system and the nitrogen distribution system are respectively connected to the hydrogen inlet and the nitrogen inlet on the gas mixer. After the gas purified by the exhaust gas recovery mechanism is analyzed online, it is re-proportioned by the hydrogen distribution system and the nitrogen distribution system according to the production process requirements of the annealing furnace of the silicon steel heat treatment line, and then enters the annealing furnace of the silicon steel heat treatment line for production.

[0021] The purified gas enters the gas mixer through the waste gas recovery pipe. According to the production process requirements of the silicon steel heat treatment line annealing furnace, the amount of hydrogen and nitrogen introduced into the gas mixer is adjusted to obtain the nitrogen-hydrogen ratio required by the production process of the silicon steel heat treatment line annealing furnace, and then introduced into the silicon steel heat treatment line annealing furnace through the protective gas inlet for production. The hydrogen gas distribution system and the nitrogen gas distribution system control the pressure and flow of hydrogen and nitrogen respectively to meet the process requirements.

[0022] The first relief branch pipe and the second relief branch pipe are respectively provided with a first relief valve 11 and a second relief valve 12.

[0023] The exhaust gas recovery pipe is provided with a first shut-off valve 13 and a second shut-off valve 14 at the inlet and outlet of the exhaust gas emission recovery mechanism respectively; the exhaust gas recovery pipe is provided with a third shut-off valve 15 at a position between the second venting branch pipe and the protective gas distribution mechanism.

[0024] The first vent valve and the first cut-off valve realize the switching between exhaust gas emission recovery and release, so as to facilitate the normal operation of the unit when the exhaust gas emission recovery mechanism is not put into operation; the first cut-off valve and the second cut-off valve are used to realize the online maintenance and replacement of the exhaust gas emission recovery mechanism; the second vent valve and the third cut-off valve are used to control the release and discharge or reuse of the purified gas.

[0025] The above content is only used to help understand the method and core idea of ​​the utility model, and is not intended to limit the utility model; at the same time, a person skilled in the art can also understand that according to the idea of ​​the utility model, there may be changes in the specific implementation method and scope of application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the utility model are included in the protection scope of the utility model.

Claims

1. A nitrogen and hydrogen gas recovery system for silicon steel, characterized in that: It includes an annealing furnace for a silicon steel heat treatment line, a waste gas emission recovery mechanism and a protective gas distribution mechanism. A waste gas emission port is provided on the top of the annealing furnace for the silicon steel heat treatment line. The waste gas emission port is respectively connected to a waste gas recovery pipe and one end port of a first venting branch pipe. The other end port of the waste gas recovery pipe is connected to a protective gas inlet of the annealing furnace for the silicon steel heat treatment line. The waste gas emission recovery mechanism and the protective gas distribution mechanism are sequentially provided on the waste gas recovery pipe.

2. A nitrogen and hydrogen gas recovery system for silicon steel according to claim 1, characterized in that: A second venting branch pipe is provided on the waste gas recovery pipe at a position between the waste gas emission recovery mechanism and the protective gas distribution mechanism.

3. A nitrogen and hydrogen gas recovery system for silicon steel according to claim 2, characterized in that: The exhaust gas recovery mechanism includes a high-temperature heat exchanger, a filter and an online gas analyzer. The exhaust gas is subjected to gas composition analysis after heat exchange cooling and filtration purification.

4. A nitrogen and hydrogen gas recovery system for silicon steel according to claim 2 or 3, characterized in that: The protective gas distribution mechanism comprises a gas mixer, a hydrogen distribution system and a nitrogen distribution system, and the hydrogen distribution system and the nitrogen distribution system are respectively connected to the hydrogen inlet and the nitrogen inlet on the gas mixer.

5. A nitrogen and hydrogen gas recovery system for silicon steel according to claim 4, characterized in that: The first relief branch pipe and the second relief branch pipe are respectively provided with a first relief valve and a second relief valve.

6. A nitrogen and hydrogen gas recovery system for silicon steel according to claim 5, characterized in that: The exhaust gas recovery pipe is provided with a first shut-off valve and a second shut-off valve respectively at the positions of the inlet and the outlet of the exhaust gas emission recovery mechanism.

7. A nitrogen and hydrogen gas recovery system for silicon steel according to claim 6, characterized in that: The waste gas recovery pipe is provided with a third shut-off valve at a position between the second venting branch pipe and the protective gas distribution mechanism.

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