Centrifugal single-cylinder synthesis gas compressor device

Abstract

A centrifugal single-cylinder synthesis gas compressor device comprises a cylinder body, a rotor rotationally connected in the cylinder body, a multi-stage impeller arranged on the rotor in series, an inlet end cover arranged at the upper end of the cylinder body, a gas inlet arranged above the inlet end cover, an outlet end cover arranged at the lower end of the cylinder body, and a gas outlet arranged below the outlet end cover. Traditional high-pressure and low-pressure double cylinders are integrated into one single cylinder, the production cost of the compressor is reduced, the manufacturing period is shortened, when the single-cylinder compressor operates, the load of a steam turbine is light, the occupied area of a unit is small, and the purchasing cost is reduced for owners.

Description

Technical Field

[0001] The utility model relates to the technical field of large-scale coal chemical synthesis ammonia, in particular to a centrifugal single-cylinder synthesis gas compressor device. Background Art

[0002] In the coal-to-ammonia synthesis unit, the raw gas pressure required for ammonia synthesis is 14MPa, while the outlet pressure of the liquid nitrogen washing unit in the front section is only 5.4MPa. Therefore, a synthesis gas compressor is needed to pressurize the hydrogen and nitrogen from the liquid nitrogen washing unit and send it to the ammonia synthesis section for ammonia synthesis reaction. The current centrifugal synthesis gas compressor consists of a fresh gas section and a circulation section. Due to the high pressure ratio, it is generally designed as a dual-cylinder structure of low-pressure cylinder + high-pressure cylinder. Figure 1 As shown in the figure, the low-pressure cylinder is the first-stage compression of fresh gas, and the second-stage compression and circulation stage of fresh gas share a high-pressure cylinder. An impeller is designed in the high-pressure cylinder to realize the compression process of the circulating gas. In order to ensure the stability of the unit gas volume, a pipeline and an anti-surge valve are designed from the first-stage outlet to the first-stage inlet, and a pipeline and an anti-surge valve are designed from the circulation stage outlet to the second-stage inlet. Both the high-pressure and low-pressure cylinders adopt a vertically split cylindrical structure, and are connected to the steam turbine with a diaphragm coupling. A check valve is designed between the high-pressure and low-pressure cylinders to prevent gas backflow. The disadvantages of the double-cylinder centrifugal synthesis gas compressor are: the double cylinder occupies a large area; the steam turbine drives the double cylinder to run with heavy load; the double cylinder uses more materials and has high manufacturing costs; the double cylinder compressor has a large workload during maintenance. Summary of the invention

[0003] The technical problem to be solved by the utility model is to provide a centrifugal single-cylinder synthesis gas compressor device to solve the problems of large footprint of the centrifugal double-cylinder synthesis gas compressor, heavy load of the double-cylinder operation driven by the steam turbine, large material consumption, high manufacturing cost, and large maintenance workload of the double-cylinder compressor.

[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is:

[0005] A centrifugal single-cylinder synthetic gas compressor device comprises a cylinder body, a rotatably connected rotor is arranged in the cylinder body, a multi-stage impeller is arranged in series on the rotor, an inlet end cover is arranged at the upper end of the cylinder body, an air inlet is arranged above the inlet end cover, an outlet end cover is arranged at the lower end of the cylinder body, and an air outlet is arranged below the outlet end cover.

[0006] The air inlet at the upper end of the inlet end cover is provided with a first-stage inlet, a second-stage inlet and a circulation-stage inlet in sequence from front to back along the multi-stage impeller.

[0007] The air outlet below the outlet end cover is provided with a first-stage outlet and a circulation-stage outlet in sequence from front to back along the multi-stage impeller. The first-stage outlet is arranged behind the first-stage inlet on the rotor axis, and the circulation-stage outlet is arranged behind the second-stage inlet on the rotor axis.

[0008] The above-mentioned inlet section is connected to the outlet end of the inlet separator, the inlet section of the inlet separator is connected to the intake pipe, the outlet section is connected to the inlet of an outlet cooler, and the outlet section of the outlet cooler is connected to the inlet of the second section through the exhaust pipe one.

[0009] The inlet of the circulation section is provided with an inlet separator, and the inlet end of the inlet separator is connected to the air intake pipeline.

[0010] The outlet of the circulation section is connected to the synthesis tower through the exhaust pipe 2.

[0011] The inlet end of the inlet separator connected to the first inlet is provided with a three-return one-surge valve.

[0012] The inlet end of the inlet separator connected to the inlet of the circulation section is provided with a three-return three-surge valve, and the three-return three-surge valve is connected to the three-return one-surge valve supply pipe.

[0013] The above-mentioned impeller has eight stages in total, the first seven stages of impellers are the fresh gas compression end, and the eighth stage of impeller is the circulation section.

[0014] The utility model provides a centrifugal single-cylinder synthetic gas compressor device, which integrates traditional high- and low-pressure double cylinders into a single cylinder, reduces the production cost of the compressor, shortens the manufacturing cycle, and has a lighter turbine load when the single-cylinder compressor is running. The unit occupies a small area, thereby reducing procurement costs for owners. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The utility model is further described below in conjunction with the accompanying drawings and embodiments:

[0016] Figure 1 This is a schematic diagram of the utility model before transformation;

[0017] Figure 2 This is a schematic diagram of the structure of the centrifugal single-cylinder compressor of the utility model;

[0018] Figure 3 This is a schematic diagram of the connection of a single-cylinder compressor of the present utility model.

[0019] In the figure: rotor 1, thrust bearing 2, cover 3, locking part 4, inlet end cover 5, thrust side shaft end sealing device 6, gas sealing device 7, cylinder body 8, flow device 9, outlet end cover 10, non-thrust side shaft end sealing device 11, radial bearing 12, end flange 13, intake pipe 14, inlet separator 15, first stage outlet cooler 16, exhaust pipe one 17, reflux cooler 18, exhaust pipe two 19, three-return one surge valve 20, three-return three surge valves 21, first stage inlet 22, second stage inlet 23, circulation section inlet 24, first stage outlet 25, circulation section outlet 26. DETAILED DESCRIPTION

[0020] like Figure 2 and 3 As shown in the figure, a centrifugal single-cylinder synthesis gas compressor device includes a cylinder body 8, a rotatably connected rotor 1 is provided in the cylinder body 8, a multi-stage impeller is arranged in series on the rotor 1, an inlet end cover 5 is provided at the upper end of the cylinder body 8, an air inlet is provided above the inlet end cover 5, an outlet end cover 10 is provided at the lower end of the cylinder body 8, and an air outlet is provided below the outlet end cover 10.

[0021] The air inlet at the upper end of the inlet cover 5 is provided with a first stage inlet 22, a second stage inlet 23 and a circulation stage inlet 24 in sequence from front to back along the multi-stage impeller.

[0022] The air outlet below the above-mentioned outlet end cover 10 is provided with a first-stage outlet 25 and a circulation-stage outlet 26 in sequence from front to back along the multi-stage impeller. The first-stage outlet 25 is arranged behind the first-stage inlet 22 on the axis of the rotor 1, and the circulation-stage outlet 26 is arranged behind the second-stage inlet 23 on the axis of the rotor 1.

[0023] The above-mentioned first inlet 22 is connected to the outlet end of the inlet separator 15, the inlet section of the inlet separator 15 is connected to the intake pipe 14, the first outlet 25 is connected to the inlet of the first outlet cooler 16, and the outlet section of the first outlet cooler 16 is connected to the second inlet 23 through the exhaust pipe 17.

[0024] The circulation section inlet 24 is provided with an inlet separator 15 , and the inlet end of the inlet separator 15 is connected to the air intake pipe 14 .

[0025] The circulation section outlet 26 is connected to the synthesis tower via the exhaust pipe 19.

[0026] A three-return-one-surge valve 20 is provided at the inlet end of the inlet separator 15 connected to the first inlet 22 .

[0027] A three-return three-surge valve 21 is provided at the inlet end of the inlet separator 15 connected to the circulation section inlet 24 , and the three-return three-surge valve 21 is connected to the three-return one-surge valve 20 supply pipe.

[0028] Working principle:

[0029] When the single-cylinder synthesis gas compressor is operating normally, the hydrogen and nitrogen coming from the liquid nitrogen wash are separated into gas and water by the inlet separator 15 through the intake pipe 14 and then enter the single-cylinder synthesis gas compressor driven by the steam turbine for gas compression. The hydrogen and nitrogen with a pressure of 9MPa after compression are cooled by the first-stage outlet cooler 16 and sent to the second-stage compression through the exhaust pipe 17. The gas after the second-stage compression is combined with the circulating gas and enters the circulation section for compression, and is cooled by the reflux cooler 18 and then sent to the synthesis tower through the exhaust pipe 19. After being cooled by the reflux cooler 18, part of the circulating gas is sent to the fresh gas inlet and the circulating gas inlet by the three-return one surge valve 20 and the three-return three surge valve 21 respectively to prevent surge and damage to the unit caused by the small gas volume unit.

[0030] When the rotor rotates at high speed, hydrogen and nitrogen are thrown out of the impeller as the impeller rotates under the action of centrifugal force, forming a vacuum zone in the center of the impeller. At this time, hydrogen and nitrogen from the outside are sucked into the impeller; as the impeller continues to rotate, the kinetic energy of the gas increases, and then it enters the diffuser with a gradually expanding flow area. Its kinetic energy decreases and its pressure energy increases, and it enters the next-stage impeller through the bend and the return flow device. The gas is continuously sucked in and thrown out, thereby maintaining the continuous flow of the gas and converting the mechanical energy into the pressure energy of the gas.

Claims

1. A centrifugal single-cylinder synthesis gas compressor device, characterized in that: The invention comprises a cylinder body (8), a rotor (1) rotatably connected therein is provided, a plurality of impellers are arranged in series on the rotor (1), an inlet cover (5) is provided at the upper end of the cylinder body (8), an air inlet is provided above the inlet cover (5), an outlet cover (10) is provided at the lower end of the cylinder body (8), and an air outlet is provided below the outlet cover (10).

2. A centrifugal single-cylinder synthesis gas compressor device according to claim 1, characterized in that: The air inlet at the upper end of the inlet end cover (5) is provided with a first-stage inlet (22), a second-stage inlet (23) and a circulation-stage inlet (24) in sequence from front to back along the multi-stage impeller.

3. A centrifugal single-cylinder synthesis gas compressor device according to claim 2, characterized in that: The air outlet below the outlet end cover (10) is provided with a first-stage outlet (25) and a circulation-stage outlet (26) in sequence from front to back along the multi-stage impeller, the first-stage outlet (25) being arranged behind the first-stage inlet (22) on the axis of the rotor (1), and the circulation-stage outlet (26) being arranged behind the second-stage inlet (23) on the axis of the rotor (1).

4. A centrifugal single-cylinder synthesis gas compressor device according to claim 3, characterized in that: The first inlet (22) is connected to the outlet end of the inlet separator (15), the inlet section of the inlet separator (15) is connected to the air intake pipe (14), the first outlet (25) is connected to the inlet of the first outlet cooler (16), and the outlet of the first outlet cooler (16) is connected to the second inlet (23) via the exhaust pipe one (17).

5. A centrifugal single-cylinder synthesis gas compressor device according to claim 4, characterized in that: The circulation section inlet (24) is provided with an inlet separator (15), and the inlet end of the inlet separator (15) is connected to the air intake pipe (14).

6. A centrifugal single-cylinder synthesis gas compressor device according to claim 5, characterized in that: The circulation section outlet (26) is connected to the synthesis tower via the second exhaust pipe (19).

7. A centrifugal single-cylinder synthesis gas compressor device according to claim 6, characterized in that: The inlet end of the inlet separator (15) connected to the first inlet (22) is provided with a three-return one-surge valve (20).

8. A centrifugal single-cylinder synthesis gas compressor device according to claim 7, characterized in that: The inlet end of the inlet separator (15) connected to the circulation section inlet (24) is provided with a three-return three-surge valve (21), and the three-return three-surge valve (21) is connected to the three-return one-surge valve (20) supply pipe.

9. A centrifugal single-cylinder synthesis gas compressor device according to claim 7, characterized in that: The impeller has eight stages in total, the first seven stages of impellers are fresh gas compression ends, and the eighth stage of impellers is a circulation section.

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