Nitrogen supply system of continuous annealing unit

Abstract

The invention discloses a continuous annealing unit nitrogen supply system which comprises an air input device and a nitrogen output device, and the air input device is communicated with the nitrogen output device through a plurality of nitrogen preparation devices connected in parallel. And each nitrogen output device comprises an air purification device, a nitrogen generation device and a nitrogen purification device which are connected in sequence. According to the nitrogen supply system of the continuous annealing unit, the nitrogen preparation devices which are connected in parallel are used for preparing nitrogen, the two modes of the small-gas-volume nitrogen requirement and the large-gas-volume nitrogen requirement are met, efficient gas supply is achieved, and the production cost is saved.

Description

Technical Field

[0001] The invention belongs to the technical field of nitrogen supply systems, and in particular relates to a nitrogen supply system for a continuous annealing unit. Background Art

[0002] The nitrogen supply system provides high-purity nitrogen protection for the continuous annealing unit, preventing the steel from coming into contact with oxygen in the air under high temperature conditions, preventing oxidation and ensuring the smoothness and quality of the steel surface.

[0003] In the prior art, nitrogen is generally supplied through a nitrogen generator set, and high-purity nitrogen is obtained by air purification, nitrogen separation and nitrogen purification. However, nitrogen supply through a single nitrogen generator set is prone to instability. Summary of the invention

[0004] The purpose of the present invention is to provide a nitrogen supply system for a continuous annealing unit, so as to solve the problem of instability in the prior art of nitrogen supply through a single nitrogen generator unit.

[0005] To this end, the present invention provides a nitrogen supply system for a continuous annealing unit, comprising an air input device and a nitrogen output device, wherein the air input device is connected to the nitrogen output device through a plurality of parallel nitrogen preparation devices, and each of the nitrogen output devices comprises an air purification device, a nitrogen preparation device and a nitrogen purification device connected in sequence.

[0006] Preferably, a first air process tank is provided between the air input device and the air purification device in each of the nitrogen preparation devices.

[0007] Preferably, a second air process tank is provided between the air purification device and the nitrogen production device in each of the nitrogen preparation devices.

[0008] Preferably, the outlets of the air purification devices in the plurality of nitrogen preparation devices are connected and then respectively connected to each of the second air process tanks.

[0009] Preferably, a first nitrogen process tank is provided between the nitrogen production device and the nitrogen purification device in each of the nitrogen preparation devices.

[0010] Preferably, the outlets of the plurality of second nitrogen process tanks are connected to each of the nitrogen purification devices respectively.

[0011] Preferably, a second nitrogen process tank is provided between the nitrogen purification device and the nitrogen output device.

[0012] Preferably, the outlets of the plurality of second nitrogen process tanks are connected to the nitrogen output device.

[0013] Preferably, the nitrogen purification device is connected to a hydrogen connecting pipe, a water inlet main pipe and a water outlet main pipe.

[0014] Preferably, the nitrogen output device is connected to a backup high-purity nitrogen system.

[0015] Beneficial effects:

[0016] 1. The present invention provides a nitrogen supply system for a continuous annealing unit, which produces nitrogen through a plurality of nitrogen preparation devices connected in parallel, meets two modes of small-volume nitrogen demand and large-volume nitrogen demand, realizes efficient gas supply, and saves production costs.

[0017] 2. The present invention provides a second air process tank to buffer and stabilize air pressure, absorb air pressure fluctuations in the air purification device, ensure that the air flow and pressure sent to the nitrogen generator remain stable, improve nitrogen production efficiency and output, and prevent air pressure fluctuations from affecting the nitrogen production equipment, so that it can run smoothly, reduce wear of the nitrogen production equipment, and extend the service life of the nitrogen production equipment. At the same time, the air in the air purification system can also be subjected to sedimentation treatment to reduce impurities in the air and prevent the nitrogen generated in the nitrogen production device from being contaminated.

[0018] 3. The present invention provides a second nitrogen process tank for storing purified nitrogen, which plays a buffering role when the nitrogen supply fluctuates, balances the nitrogen flow and pressure, ensures the continuity and stability of the nitrogen supply, and guarantees the gas supply demand. At the same time, it can protect downstream equipment, prevent the instantaneous pressure fluctuations that occur when the production line is started from causing damage to downstream equipment, and extend the service life of downstream equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 The figure is a pipeline diagram of a nitrogen supply system of a continuous annealing unit in the present invention.

[0021] Figure 2 The present invention is a pipeline diagram of an air purification device and a nitrogen production device of a nitrogen supply system of a continuous annealing unit.

[0022] Figure 3 The present invention is a pipeline diagram of a nitrogen production device and a nitrogen output device of a nitrogen supply system of a continuous annealing unit.

[0023] In the figure: 1-air input device, 2-air purification device, 3-nitrogen production device, 4-nitrogen purification device, 5-nitrogen output device, 6-first air process tank, 7-second air process tank, 8-first nitrogen process tank, 9-second nitrogen process tank, 10-standby high-purity nitrogen system. DETAILED DESCRIPTION

[0024] The content of the present invention can be more easily understood by selecting the following detailed description of the preferred implementation method of the present invention and the embodiments included. Unless otherwise specified, all technical and scientific terms used herein have the same meanings as those of ordinary skill in the art to which the present invention belongs. When there is a conflict, the definition in this specification shall prevail.

[0025] Embodiment 1:

[0026] like Figure 1 As shown, this embodiment provides a nitrogen supply system for a continuous annealing unit, comprising the following steps:

[0027] The air input device 1 and the nitrogen output device 5 are connected via a plurality of parallel nitrogen preparation devices, and each nitrogen output device 5 comprises an air purification device 2, a nitrogen preparation device 3 and a nitrogen purification device 4 which are connected in sequence.

[0028] In one embodiment, there are at least three nitrogen production devices.

[0029] like Figure 2 As shown, a first air process tank 6 is arranged between the air input device 1 and the air purification device 2 in each nitrogen preparation device.

[0030] A second air process tank 7 is provided between the air purification device 2 and the nitrogen making device 3 in each nitrogen preparation device. The outlets of the three air purification devices 2 are connected and then connected to each second air process tank 7 respectively. The second air process tank 7 can play a role in buffering and stabilizing the air pressure, absorbing the air pressure fluctuation in the air purification device 2, ensuring that the air flow and pressure sent to the nitrogen making machine remain stable, improving the nitrogen making efficiency and output, and preventing the influence of air pressure fluctuation on the nitrogen making equipment, so that it can run smoothly, reduce the wear of the nitrogen making device 3, and extend the service life of the nitrogen making device 3. At the same time, the air in the air purification system can also be subjected to sedimentation treatment to reduce impurities in the air and prevent the nitrogen generated in the nitrogen making device 3 from being contaminated.

[0031] like Figure 3 As shown, a first nitrogen process tank 8 is provided between the nitrogen making device 3 and the nitrogen purification device 4 in each nitrogen preparation device. The outlets of the three second nitrogen process tanks are connected to each nitrogen purification device 4 respectively.

[0032] A second nitrogen process tank 9 is provided between the nitrogen purification device 4 and the nitrogen output device 5. The outlets of the three second nitrogen process tanks 9 are connected to the nitrogen output device 5. The second nitrogen process tank 9 is used to store purified nitrogen, and plays a buffering role when the nitrogen supply fluctuates, balances the nitrogen flow and pressure, ensures the continuity and stability of the nitrogen supply, and guarantees the gas supply demand. At the same time, it can protect downstream equipment, prevent the instantaneous pressure fluctuations that occur when the production line is started from causing damage to the downstream equipment, and extend the service life of the downstream equipment.

[0033] In one embodiment, the air input device 1 is an air compressor for providing compressed air. The nitrogen output device 5 is an L-shaped furnace.

[0034] The air purification device 2 is used to purify the compressed air, including a cold dryer, a three-stage filter and an activated carbon filter. The cold dryer is between the three-stage filters. The cold dryer and the three-stage filter are connected with a sewage pipe for discharging the filtered sewage. The nitrogen preparation device is used to separate the nitrogen in the compressed air. In this embodiment, the nitrogen preparation device is a PSA nitrogen generator. The nitrogen purification device 4 is used to purify nitrogen. The nitrogen purification device 4 is connected with a hydrogen pipe, a water inlet pipe and a water outlet pipe.

[0035] The nitrogen output device 5 is connected to a standby high-purity nitrogen system 10. The high-purity nitrogen system includes a liquid nitrogen storage tank, a liquid nitrogen vaporizer, and a nitrogen pressure reducing valve group connected in sequence. The standby high-purity nitrogen system 10 is used to provide standby nitrogen, vaporizes the liquid nitrogen in the liquid nitrogen storage tank into nitrogen through the liquid nitrogen vaporizer, and inputs it into the nitrogen output device 5 through the nitrogen pressure reducing valve group.

[0036] Working principle: the nitrogen output device 5 in the nitrogen supply system in this embodiment has two requirements: small amount of nitrogen output and large amount of nitrogen output. The small amount of nitrogen output is used for the production of the continuous annealing machine, and the large amount of nitrogen output is used for purging.

[0037] In actual use, the small-volume nitrogen output mode requires 1,500 cubic meters of gas supply, and the large-volume purge mode requires 2,200 cubic meters of gas supply. The conventional nitrogen supply system uses three sets of supply equipment for two uses and one backup, providing a total of 2,200 cubic meters of gas supply, of which two sets of equipment provide 1,100 cubic meters of gas supply and one set of equipment is used as backup. However, when supplying a small amount of nitrogen, one set of nitrogen supply equipment can only provide 1,100 cubic meters of gas supply. If the gas supply is insufficient, two sets of nitrogen supply equipment will cause waste.

[0038] In this embodiment, the gas supply of a single nitrogen preparation device is optimized, and the gas supply of each nitrogen supply device is 750 cubic meters. The design of reducing the scale of the equipment makes the system more stable in actual operation. When a small amount of nitrogen is supplied, two nitrogen preparation devices are turned on to provide a gas supply of 1,500 cubic meters, and according to the working cycle characteristics of the nitrogen making device 3, the nitrogen preparation device is switched at 80 seconds, and the three nitrogen preparation devices work in turn. When a large amount of nitrogen is supplied, the three nitrogen preparation devices are operated at the same time, and a total of 2,250 cubic meters of gas supply is provided, which can meet the functional requirements of purging. Due to the reduced workload of a single device, the equipment switching and operation process are smoother, the failure rate is reduced, and the reliability and stability of the overall system are improved. In addition, the use of smaller equipment can extend the operating life of the equipment, reduce maintenance costs, and further improve the efficiency and sustainability of the system.

[0039] The embodiments described above are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A nitrogen supply system for a continuous annealing unit, characterized in that: include: An air input device and a nitrogen output device, wherein the air input device and the nitrogen output device are connected through a plurality of parallel nitrogen preparation devices, and each of the nitrogen output devices comprises an air purification device, a nitrogen preparation device and a nitrogen purification device which are connected in sequence.

2. A nitrogen supply system for a continuous annealing unit according to claim 1, characterized in that: A first air process tank is arranged between the air input device and the air purification device in each nitrogen preparation device.

3. A nitrogen supply system for a continuous annealing unit according to claim 1, characterized in that: A second air process tank is arranged between the air purification device and the nitrogen production device in each of the nitrogen preparation devices.

4. A nitrogen supply system for a continuous annealing unit according to claim 3, characterized in that: The outlets of the air purification devices in the plurality of nitrogen preparation devices are connected and then respectively connected to each of the second air process tanks.

5. A nitrogen supply system for a continuous annealing unit according to claim 1, characterized in that: A first nitrogen process tank is arranged between the nitrogen production device and the nitrogen purification device in each of the nitrogen preparation devices.

6. A nitrogen supply system for a continuous annealing unit according to claim 5, characterized in that: The outlets of the plurality of second nitrogen process tanks are connected to each of the nitrogen purification devices respectively.

7. A nitrogen supply system for a continuous annealing unit according to claim 1, characterized in that: A second nitrogen process tank is arranged between the nitrogen purification device and the nitrogen output device.

8. A nitrogen supply system for a continuous annealing unit according to claim 7, characterized in that: The outlets of the plurality of second nitrogen process tanks are connected to the nitrogen output device.

9. A nitrogen supply system for a continuous annealing unit according to claim 1, characterized in that: The nitrogen purification device is connected with a hydrogen connecting pipe, a water inlet main pipe and a water outlet main pipe.

10. The nitrogen supply system for a continuous annealing unit according to claim 1, characterized in that: The nitrogen output device is connected to a spare high-purity nitrogen system.

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