Cryogenic nitrogen generation device

Abstract

The utility model provides a cryogenic nitrogen-making device which sequentially comprises a self-cleaning filter, an air compressor, an air pre-cooling unit, a molecular sieve adsorber, a booster expansion turbine and a nitrogen rectifying tower according to a liquid nitrogen production sequence, and a liquid nitrogen outlet of the nitrogen rectifying tower is connected with a gas supply and storage tank assembly. The gas supply and storage tank assembly comprises a gas supply main pipeline and gas storage branch pipelines connected in parallel with the lower portion of the gas supply main pipeline. Due to the arrangement of the gas supply main pipeline, the gas storage branch pipeline, the first one-way valve, the second one-way valve, the nitrogen storage tank, the connecting valve, the vaporizer and the third one-way valve, liquid nitrogen can enter and exit for storage, and supply of the liquid nitrogen is guaranteed when nitrogen load is interrupted or air separation equipment is overhauled.

Description

Technical Field

[0001] The utility model belongs to the technical field of cryogenic nitrogen production, and particularly relates to a cryogenic nitrogen production device. Background Art

[0002] The PSA nitrogen production process is a traditional industrial nitrogen production process. This nitrogen production process requires low investment, is simple to operate, and has high nitrogen purity. However, it has high energy consumption and low nitrogen output, which leads to a shortage of nitrogen for production and the need to purchase liquid nitrogen for supplementation, increasing production costs. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides a cryogenic nitrogen making device, which adopts cryogenic nitrogen making technology to achieve the purpose of energy saving and consumption reduction, and can store liquid nitrogen in and out, thereby ensuring the supply of liquid nitrogen during inspection and maintenance.

[0004] The utility model is realized by the following technical solutions:

[0005] A cryogenic nitrogen production device comprises, in order of liquid nitrogen production, a self-cleaning filter, an air compressor, an air precooling unit, a molecular sieve adsorber, a booster turbine expander, and a nitrogen distillation tower. A gas supply and storage tank assembly is connected to the liquid nitrogen outlet of the nitrogen distillation tower. The gas supply and storage tank assembly comprises a gas supply main line and a gas storage branch line connected in parallel at the lower part of the gas supply main line.

[0006] Preferably, a first one-way valve is installed in series on the main gas supply line.

[0007] Preferably, a second one-way valve, a nitrogen storage tank, a connecting valve, a vaporizer and a third one-way valve are installed on the gas storage branch pipeline in sequence according to the flow direction of liquid nitrogen.

[0008] Compared with the prior art, the beneficial effects of the utility model are:

[0009] 1. In the utility model, the arrangement of the gas supply main pipeline, the gas storage branch pipeline, the first one-way valve, the second one-way valve, the nitrogen storage tank, the connecting valve, the vaporizer, and the third one-way valve is conducive to the storage of liquid nitrogen in and out, thereby ensuring the supply of liquid nitrogen when the nitrogen load is interrupted or the air separation equipment is overhauled.

[0010] 2. In the utility model, the self-cleaning filter, air compressor, air precooling unit, molecular sieve adsorber, booster turbine expander, and nitrogen distillation tower are arranged to facilitate the preparation of liquid nitrogen. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 It is a structural schematic diagram of the utility model.

[0012] Figure 2It is a structural schematic diagram of the gas supply and gas storage tank assembly of the utility model.

[0013] In the figure:

[0014] 1. Self-cleaning filter; 2. Air compressor; 3. Air pre-cooling unit; 4. Molecular sieve adsorber; 5. Booster turbine expander; 6. Nitrogen distillation tower; 7. Gas supply and storage tank assembly; 71. Gas supply main line; 72. Gas storage branch line; 73. First one-way valve; 74. Second one-way valve; 75. Nitrogen storage tank; 76. Connecting valve; 77. Vaporizer; 78. Third one-way valve. DETAILED DESCRIPTION

[0015] The utility model is described in detail below in conjunction with the accompanying drawings. Figure 1 As shown, a cryogenic nitrogen production device includes, in the order of liquid nitrogen production, a self-cleaning filter 1, an air compressor 2, an air precooling unit 3, a molecular sieve adsorber 4, a booster turbine expander 5, and a nitrogen distillation tower 6. The liquid nitrogen outlet of the nitrogen distillation tower 6 is connected to a gas supply and storage tank assembly 7.

[0016] In this embodiment, combined with the Figure 2 As shown, the gas supply and storage tank assembly 7 includes a gas supply main line 71 and a gas storage branch line 72 connected in parallel at the lower part of the gas supply main line 71. The gas supply main line 71 is serially installed with a first check valve 73. The gas storage branch line 72 is sequentially installed with a second check valve 74, a nitrogen storage tank 75, a connecting valve 76, a vaporizer 77 and a third check valve 78 according to the flow direction of liquid nitrogen. The gas supply main line 71 and the first check valve 73 meet the real-time working requirements of liquid nitrogen. According to the technical requirements, the third one-way valve 78 prevents the liquid nitrogen in the gas supply main line 71 from flowing back to the vaporizer 77; by opening the second one-way valve 74, the liquid nitrogen can enter the nitrogen storage tank 75 for storage; when the nitrogen load is interrupted or the air separation equipment is overhauled, the liquid nitrogen in the nitrogen storage tank 75 enters the vaporizer 77 and is heated, and then the nitrogen enters the nitrogen pipeline network to meet the demand for nitrogen, and the first one-way valve 73 prevents the nitrogen from flowing back to the nitrogen distillation tower 6 through the gas supply main line 71.

[0017] In this embodiment, specifically, the liquid nitrogen flow direction of the main gas supply line 71 is the communication direction of the first one-way valve 73 .

[0018] In this embodiment, specifically, the liquid nitrogen flow direction of the gas storage branch pipeline 72 is the communication direction of the second one-way valve 74 and the third one-way valve 78 .

[0019] How it works

[0020] In the utility model, the air is passed through a self-cleaning filter 1 to remove dust and impurities, thereby ensuring the normal operation of downstream equipment and the purity of the product. The air is compressed and heated by an air compressor 2, and then enters an air precooling unit 3 for cooling. The load of the purification system is reduced by lowering the air temperature and the water content, and then water vapor, carbon dioxide and hydrocarbons are separated by a molecular sieve adsorber 4. After being pressurized by a booster turbine expander 5, liquid nitrogen is produced by a nitrogen rectification tower 6. The cryogenic nitrogen production technology is adopted to achieve the purpose of energy saving and consumption reduction. The cryogenic air separation nitrogen production has a large gas output and a high purity of product nitrogen, which is suitable for large-scale industrial nitrogen production. The energy consumption of nitrogen production is relatively low, which is about 60% of the cost of nitrogen production by PSA adsorption.

[0021] Utilizing the technical solution described in the utility model, or those skilled in the art designing similar technical solutions inspired by the technical solution of the utility model to achieve the above-mentioned technical effects, all fall within the protection scope of the utility model.

Claims

1. A cryogenic nitrogen production device, characterized in that: The invention comprises, in order of liquid nitrogen production, a self-cleaning filter (1), an air compressor (2), an air precooling unit (3), a molecular sieve adsorber (4), a booster turbine expander (5), and a nitrogen distillation tower (6). The liquid nitrogen outlet of the nitrogen distillation tower (6) is connected to a gas supply and storage tank assembly (7). The gas supply and storage tank assembly (7) comprises a gas supply main line (71) and a gas storage branch line (72) connected in parallel to the lower part of the gas supply main line (71).

2. The cryogenic nitrogen generator according to claim 1, characterized in that: A first one-way valve (73) is installed in series on the main gas supply line (71).

3. The cryogenic nitrogen generator according to claim 1, characterized in that: The gas storage branch pipeline (72) is provided with a second one-way valve (74), a nitrogen storage tank (75), a connecting valve (76), a vaporizer (77) and a third one-way valve (78) in sequence according to the flow direction of liquid nitrogen.

4. The cryogenic nitrogen generator according to claim 1, characterized in that: The liquid nitrogen flow direction of the main gas supply line (71) is the communication direction of the first one-way valve (73).

5. The cryogenic nitrogen generator according to claim 1, characterized in that: The liquid nitrogen flow direction of the gas storage branch pipeline (72) is the communication direction of the second one-way valve (74) and the third one-way valve (78).

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