Energy-saving high-yield nitrogen production system

Abstract

The utility model discloses an energy -conserving high yield nitrogen making system belongs to nitrogen making technical field. Including first pressure swing adsorption tower to fourth pressure swing adsorption tower, first inlet valve to fourth inlet valve, first outlet valve to fourth outlet valve, first exhaust valve to fourth exhaust valve, first pressure -equalizing valve to fourth pressure -equalizing valve, nitrogen buffer tank, inlet pipe, first exhaust pipe and second exhaust pipe, the connecting line between first exhaust valve and second exhaust valve is connected with first exhaust pipe through the pipeline, and the connecting line between third exhaust valve and fourth exhaust valve is connected with second exhaust pipe through the pipeline. The utility model changes the exhaust pipeline, realizes two groups of nitrogen making system to exhaust to the outdoor alone, can improve the nitrogen production efficiency, avoids when one group of nitrogen making system exhausts the other group of nitrogen making system to return to blow and will have a large amount of oxygen to blow back into the opposite party's regenerator, influences the regenerative effect.

Description

Technical Field

[0001] This utility model belongs to the field of nitrogen production technology, and more specifically relates to an energy-saving and high-yield nitrogen production system. Background Technology

[0002] Nitrogen is widely distributed in nature and is a major component of air. In dry air, nitrogen accounts for 78% of the air. Therefore, air is the largest source of nitrogen, and it is inexhaustible.

[0003] Pressure swing adsorption (PSA) is a method of adsorption under pressure and desorption under reduced pressure (vacuum or atmospheric pressure) when the temperature remains constant. Carbon molecular sieves are activated carbon produced from coal through a special process. They are black particles with microporous crystals on their surface and are a semi-permanent adsorbent.

[0004] Nitrogen generation principle: The separation of oxygen and nitrogen by carbon molecular sieves is mainly based on the different diffusion rates of N2 and O2 on the surface of the carbon molecular sieve. Smaller diameter gas molecules (O2) diffuse faster and enter more of the solid phase (micropores) of the molecular sieve, while larger diameter gas molecules (N2) diffuse slower and enter less of the solid phase. The critical diameter of oxygen is 2.8 Å, and the critical diameter of nitrogen is 3 Å, thus nitrogen enrichment can be obtained in the gas phase. Compressed air enters the carbon molecular sieve adsorption tower. When the adsorption pressure increases, the adsorption of both oxygen and nitrogen increases simultaneously. For a short period after adsorption begins, the adsorption rate of oxygen greatly exceeds that of nitrogen. Therefore, utilizing the difference in the amount of oxygen and nitrogen adsorbed by carbon molecular sieves within a certain time, a programmable controller, according to a specific time program, combines a cycle of pressure adsorption and depressurization desorption (pressure swing adsorption process) to complete the separation of nitrogen and oxygen, thereby obtaining ordinary nitrogen gas with an oxygen content ≤2% in the gas phase.

[0005] The four PSA pressure swing adsorption towers on site are paired up into two groups, A and B. The two groups share a common exhaust pipe (oxygen). When group A exhausts and group B back-blown, a large amount of oxygen will be back-blown into the other's regeneration tower, affecting the regeneration effect.

[0006] Therefore, how to develop an energy-saving and high-yield nitrogen production system that enables units A and B to exhaust gas to the outside separately and improve nitrogen production efficiency is a technical problem that urgently needs to be solved by those skilled in the art. Utility Model Content

[0007] In view of this, the present invention provides an energy-saving and high-yield nitrogen production system.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] An energy-saving and high-yield nitrogen production system includes a first pressure swing adsorption tower to a fourth pressure swing adsorption tower, a first inlet valve to a fourth inlet valve, a first outlet valve to a fourth outlet valve, a first exhaust valve to a fourth exhaust valve, a first equalizing valve to a fourth equalizing valve, a nitrogen buffer tank, an inlet pipe, a first exhaust pipe and a second exhaust pipe.

[0010] The bottom of the first pressure swing adsorption (PSA) tower, the first inlet valve, the second inlet valve, and the bottom of the second PSA tower are sequentially connected via pipelines. The bottom of the first PSA tower, the first exhaust valve, the second exhaust valve, and the bottom of the second PSA tower are also sequentially connected via pipelines. The bottom of the first PSA tower, the first equalizing valve, and the bottom of the second PSA tower are also sequentially connected via pipelines. The top of the first PSA tower, the first outlet valve, the second outlet valve, and the top of the second PSA tower are also sequentially connected via pipelines. The top of the first PSA tower, the second equalizing valve, and the top of the second PSA tower are also sequentially connected via pipelines. The bottom, third inlet valve, fourth inlet valve, and bottom of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the bottom, third exhaust valve, fourth exhaust valve, and bottom of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the bottom, third equalizing valve, and bottom of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the top, third outlet valve, fourth outlet valve, and top of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the top, fourth equalizing valve, and top of the fourth pressure swing adsorption tower are connected in sequence via pipelines.

[0011] The connecting pipeline between the first outlet valve and the second outlet valve is connected to the inlet of the nitrogen buffer tank via a pipeline; the connecting pipeline between the third outlet valve and the fourth outlet valve is connected to the inlet of the nitrogen buffer tank via a pipeline; the connecting pipeline between the first inlet valve and the second inlet valve is connected to the inlet pipe via a pipeline; and the connecting pipeline between the third inlet valve and the fourth inlet valve is connected to the inlet pipe via a pipeline.

[0012] The connecting pipe between the first exhaust valve and the second exhaust valve is connected to the first exhaust pipe via a pipe, and the connecting pipe between the third exhaust valve and the fourth exhaust valve is connected to the second exhaust pipe via a pipe.

[0013] Furthermore, carbon molecular sieves are installed inside the first, second, third, and fourth pressure swing adsorption towers.

[0014] The beneficial effects of adopting the above-mentioned further technical solution are as follows: by utilizing the adsorption characteristics of carbon molecular sieves, combined with pressure adsorption and depressurization desorption, nitrogen and oxygen in the air can be separated to obtain the product nitrogen.

[0015] Furthermore, it also includes an air compressor, a thermal adsorption dryer, and a filter, wherein the air compressor, thermal adsorption dryer, filter, and air inlet pipe are connected in sequence via pipelines.

[0016] The beneficial effects of adopting the above-mentioned further technical solutions are as follows: the air compressor compresses air to provide raw materials, the heatless adsorption dryer removes water molecules from the compressed air, and the filter removes oil and dust from the air so that the gas meets the air requirements of the nitrogen generator inlet.

[0017] Furthermore, it also includes a PLC control system, wherein the first inlet valve to the fourth inlet valve, the first outlet valve to the fourth outlet valve, the first exhaust valve to the fourth exhaust valve, and the first equalizing valve to the fourth equalizing valve are solenoid valves, which are electrically connected to the PLC control system.

[0018] The beneficial effect of adopting the above-mentioned further technical solutions is to achieve automated nitrogen production.

[0019] Furthermore, it also includes a first manual valve to a fourth manual valve, with the connecting pipeline between the first outlet valve and the second outlet valve, the first manual valve and the nitrogen buffer tank connected in sequence via pipelines, the connecting pipeline between the third outlet valve and the fourth outlet valve, the second manual valve and the nitrogen buffer tank connected in sequence via pipelines, the connecting pipeline between the first inlet valve and the second inlet valve, the third manual valve and the air inlet pipe connected in sequence via pipelines, and the connecting pipeline between the third inlet valve and the fourth inlet valve, the fourth manual valve and the air inlet pipe connected in sequence via pipelines.

[0020] The beneficial effects of adopting the above-mentioned further technical solutions are: if one of the nitrogen generation systems fails, the manual valve can safely and conveniently disconnect that nitrogen generation system and shut down for maintenance.

[0021] The beneficial effects of this utility model are as follows: The connecting pipe between the first exhaust valve and the second exhaust valve is connected to the first exhaust pipe via a pipe, and the connecting pipe between the third exhaust valve and the fourth exhaust valve is connected to the second exhaust pipe via a pipe. By changing the exhaust pipe, the two nitrogen generation systems can exhaust to the outside independently, which can improve nitrogen production efficiency and avoid a large amount of oxygen being blown back into the other nitrogen generation system's regeneration tower when one nitrogen generation system exhausts and the other nitrogen generation system backflushes, thus affecting the regeneration effect. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the energy-saving and high-yield nitrogen production system of this utility model;

[0024] Among them, 1-first pressure swing adsorption tower, 2-second pressure swing adsorption tower, 3-third pressure swing adsorption tower, 4-fourth pressure swing adsorption tower, 5-first inlet valve, 6-second inlet valve, 7-third inlet valve, 8-fourth inlet valve, 9-first outlet valve, 10-second outlet valve, 11-third outlet valve, 12-fourth outlet valve, 13-first exhaust valve, 14-second exhaust valve, 15-third exhaust valve, 16-fourth exhaust valve, 17-first equalizing valve, 18-second equalizing valve, 19-third equalizing valve, 20-fourth equalizing valve, 21-nitrogen buffer tank, 22-inlet pipe, 23-first exhaust pipe, 24-second exhaust pipe, 25-air compressor, 26-thermal adsorption dryer, 27-filter, 28-first manual valve, 29-second manual valve, 30-third manual valve, 31-fourth manual valve. Detailed Implementation

[0025] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0026] The energy-saving and high-yield nitrogen production system includes a first pressure swing adsorption tower 1 to a fourth pressure swing adsorption tower 4, a first inlet valve 5 to a fourth inlet valve 8, a first outlet valve 9 to a fourth outlet valve 12, a first exhaust valve 13 to a fourth exhaust valve 16, a first equalizing valve 17 to a fourth equalizing valve 20, a nitrogen buffer tank 21, an inlet pipe 22, a first exhaust pipe 23 and a second exhaust pipe 24;

[0027] The bottom of the first pressure swing adsorption tower 1, the first inlet valve 5, the second inlet valve 6, and the bottom of the second pressure swing adsorption tower 2 are sequentially connected by pipelines. The bottom of the first pressure swing adsorption tower 1, the first exhaust valve 13, the second exhaust valve 14, and the bottom of the second pressure swing adsorption tower 2 are sequentially connected by pipelines. The bottom of the first pressure swing adsorption tower 1, the first pressure equalizing valve 17, and the bottom of the second pressure swing adsorption tower 2 are sequentially connected by pipelines. The top of the first pressure swing adsorption tower 1, the first outlet valve 9, the second outlet valve 10, and the top of the second pressure swing adsorption tower 2 are sequentially connected by pipelines. The top of the first pressure swing adsorption tower 1, the second pressure equalizing valve 18, and the top of the second pressure swing adsorption tower 2 are sequentially connected by pipelines. The bottom of the third pressure swing adsorption tower 3, the third inlet valve 7, the fourth inlet valve 8 and the bottom of the fourth pressure swing adsorption tower 4 are connected in sequence via pipelines. The bottom of the third pressure swing adsorption tower 3, the third exhaust valve 15, the fourth exhaust valve 16 and the bottom of the fourth pressure swing adsorption tower 4 are connected in sequence via pipelines. The bottom of the third pressure swing adsorption tower 3, the third equalizing valve 19 and the bottom of the fourth pressure swing adsorption tower 4 are connected in sequence via pipelines. The top of the third pressure swing adsorption tower 3, the third outlet valve 11, the fourth outlet valve 12 and the top of the fourth pressure swing adsorption tower 4 are connected in sequence via pipelines. The top of the third pressure swing adsorption tower 3, the fourth equalizing valve 20 and the top of the fourth pressure swing adsorption tower 4 are connected in sequence via pipelines.

[0028] The connecting pipe between the first outlet valve 9 and the second outlet valve 10 is connected to the inlet of the nitrogen buffer tank 21 via a pipe; the connecting pipe between the third outlet valve 11 and the fourth outlet valve 12 is connected to the inlet of the nitrogen buffer tank 21 via a pipe; the connecting pipe between the first inlet valve 5 and the second inlet valve 6 is connected to the inlet pipe 22 via a pipe; and the connecting pipe between the third inlet valve 7 and the fourth inlet valve 8 is connected to the inlet pipe 22 via a pipe.

[0029] The connecting pipe between the first exhaust valve 13 and the second exhaust valve 14 is connected to the first exhaust pipe 23 via a pipe, and the connecting pipe between the third exhaust valve 15 and the fourth exhaust valve 16 is connected to the second exhaust pipe 24 via a pipe.

[0030] In one embodiment, carbon molecular sieves are installed inside the first pressure swing adsorption tower 1, the second pressure swing adsorption tower 2, the third pressure swing adsorption tower 3, and the fourth pressure swing adsorption tower 4.

[0031] In one embodiment, the system further includes an air compressor 25, a thermal adsorption dryer 26, and a filter 27, wherein the air compressor 25, the thermal adsorption dryer 26, the filter 27, and the air inlet pipe 22 are connected in sequence via pipelines.

[0032] In one embodiment, the system further includes a PLC control system, wherein the first inlet valve 5 to the fourth inlet valve 8, the first outlet valve 9 to the fourth outlet valve 12, the first exhaust valve 13 to the fourth exhaust valve 16, and the first equalizing valve 17 to the fourth equalizing valve 20 are solenoid valves, which are electrically connected to the PLC control system.

[0033] In one embodiment, the system further includes a first manual valve 28 to a fourth manual valve 31, a connecting pipeline between a first outlet valve 9 and a second outlet valve 10, a first manual valve 28 and a nitrogen buffer tank 21 connected in sequence via a pipeline, a connecting pipeline between a third outlet valve 11 and a fourth outlet valve 12, a second manual valve 29 and a nitrogen buffer tank 21 connected in sequence via a pipeline, a connecting pipeline between a first inlet valve 5 and a second inlet valve 6, a third manual valve 30 and an air inlet pipe 22 connected in sequence via a pipeline, a connecting pipeline between a third inlet valve 7 and a fourth inlet valve 8, and a fourth manual valve 31 and an air inlet pipe 22 connected in sequence via a pipeline.

[0034] Table 1 Valve Switching Procedures for Energy-Saving and High-Yield Nitrogen Production Systems

[0035]

[0036]

[0037] The description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An energy-saving and high-yield nitrogen production system, characterized in that, Includes a first pressure swing adsorption tower to a fourth pressure swing adsorption tower, a first inlet valve to a fourth inlet valve, a first outlet valve to a fourth outlet valve, a first exhaust valve to a fourth exhaust valve, a first equalizing valve to a fourth equalizing valve, a nitrogen buffer tank, an inlet pipe, a first exhaust pipe and a second exhaust pipe; The bottom of the first pressure swing adsorption (PSA) tower, the first inlet valve, the second inlet valve, and the bottom of the second PSA tower are sequentially connected via pipelines. The bottom of the first PSA tower, the first exhaust valve, the second exhaust valve, and the bottom of the second PSA tower are also sequentially connected via pipelines. The bottom of the first PSA tower, the first equalizing valve, and the bottom of the second PSA tower are also sequentially connected via pipelines. The top of the first PSA tower, the first outlet valve, the second outlet valve, and the top of the second PSA tower are also sequentially connected via pipelines. The top of the first PSA tower, the second equalizing valve, and the top of the second PSA tower are also sequentially connected via pipelines. The bottom, third inlet valve, fourth inlet valve, and bottom of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the bottom, third exhaust valve, fourth exhaust valve, and bottom of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the bottom, third equalizing valve, and bottom of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the top, third outlet valve, fourth outlet valve, and top of the fourth pressure swing adsorption tower are connected in sequence via pipelines; the top, fourth equalizing valve, and top of the fourth pressure swing adsorption tower are connected in sequence via pipelines. The connecting pipeline between the first outlet valve and the second outlet valve is connected to the inlet of the nitrogen buffer tank via a pipeline; the connecting pipeline between the third outlet valve and the fourth outlet valve is connected to the inlet of the nitrogen buffer tank via a pipeline; the connecting pipeline between the first inlet valve and the second inlet valve is connected to the inlet pipe via a pipeline; and the connecting pipeline between the third inlet valve and the fourth inlet valve is connected to the inlet pipe via a pipeline. The connecting pipe between the first exhaust valve and the second exhaust valve is connected to the first exhaust pipe via a pipe, and the connecting pipe between the third exhaust valve and the fourth exhaust valve is connected to the second exhaust pipe via a pipe.

2. The energy-saving and high-yield nitrogen production system according to claim 1, characterized in that, Carbon molecular sieves are installed inside the first, second, third, and fourth pressure swing adsorption towers.

3. The energy-saving and high-yield nitrogen production system according to claim 1, characterized in that, It also includes an air compressor, a thermal adsorption dryer, and a filter, wherein the air compressor, thermal adsorption dryer, filter, and air inlet pipe are connected in sequence via pipelines.

4. The energy-saving and high-yield nitrogen production system according to claim 1, characterized in that, It also includes a PLC control system, wherein the first inlet valve to the fourth inlet valve, the first outlet valve to the fourth outlet valve, the first exhaust valve to the fourth exhaust valve, and the first equalizing valve to the fourth equalizing valve are solenoid valves, which are electrically connected to the PLC control system.

5. The energy-saving and high-yield nitrogen production system according to claim 1, characterized in that, It also includes a first manual valve to a fourth manual valve, with the connecting pipeline between the first outlet valve and the second outlet valve, the first manual valve and the nitrogen buffer tank connected in sequence via pipelines, the connecting pipeline between the third outlet valve and the fourth outlet valve, the second manual valve and the nitrogen buffer tank connected in sequence via pipelines, the connecting pipeline between the first inlet valve and the second inlet valve, the third manual valve and the air inlet pipe connected in sequence via pipelines, and the connecting pipeline between the third inlet valve and the fourth inlet valve, the fourth manual valve and the air inlet pipe connected in sequence via pipelines.

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