How many stages of compression are there in ammonia synthesis? What pressure is reached in each stage? What is the final compression ratio?

We use seven stages of compression: the inlet pressure is 320 mmHg, and the outlet pressure at stage 1 is 0.38 MPA; at stage 2 it is 0.83 MPA. The inlet pressure at stage 3 is 0.52 MPA, with an outlet pressure of 1.5 MPA at that stage. The outlet pressure at stage 4 is 3.2 MPA, at stage 5 it is 7.2 MPA, at stage 6 it is 13.5 MPA. The inlet pressure at stage 7 is 13.2 MPA, while the outlet pressure at that stage is 28.0 MPA

Divided into six sections. All values below are gauge pressure: inlet 1 at 300 mmH2O, outlet 1 at 0.25 MPa, outlet 2 at 0.8 MPa, outlet 3 at 2.15 MPa, inlet 4 at 1.8 MPa, outlet 4 at 4.5 MPa, outlet 5 at 12.5 MPa, and outlet 6 at 29 MPa.

We just started driving here; at the first outlet, the pressure is 300 mmH2O, at the second outlet it’s 0.24 MPa, at the third outlet it’s 0.8 MPa, at the fourth outlet it’s 2.1 MPa, at the fifth outlet it’s 1.9 MPa, at the sixth outlet it’s 4.5 MPa, and at the seventh outlet it’s 12.5 MPa.

The syngas compressor has a three-cylinder, four-stage design; the first stage utilizes 9 impellers for compression. The inlet pressure is 2.606 Mpa and the temperature is 37.8°C, while the outlet pressure is 6.49 Mpa and the temperature is 171°C. The compression ratio is 2.49. Compressed in two stages with 9 impellers: inlet pressure of 6.402 Mpa and temperature of 7.78°C; outlet pressure of 15.826 Mpa and temperature of 140.6°C; compression ratio of 2.47. Three stages with 5 impellers each for compression; inlet pressure of 15.77 Mpa and temperature of 37.8°C, outlet pressure of 22.72 Mpa and temperature of 98.3°C, with a compression ratio of 1.44. In the four-stage (cyclic) section, 1 impeller is used for compression; the inlet pressure is 22.06 Mpa and the temperature is 23.9°C, while the outlet pressure is 24.095 Mpa and the temperature is 34.4°C. The compression ratio is 1.09. Total compression ratio is 9.25.

Divided into six sections: the gauge pressure is 0.03 MPa for the first outlet, 0.25 MPa for the second outlet, 0.8 MPa for the third outlet, 1.7 MPa for the fourth outlet, 4.5 MPa for the fifth outlet, and 32 MPa for the sixth outlet.

There are a few places upstairs saying that the gauge pressure reaches 300 mmH2O; that can’t be right. It should be 320 mmHg, right?

You’re very careful! Generally, the pressure at the inlet of the Roots pump is 300 mmH2O; after being pressurized by the Roots pump, it reaches 300 mmHg at the inlet to the compressor stage

That’s right; many factories don’t have Roots blowers, and once pressure is applied, it becomes the pressure in the gas tank

Here we have six compression stages: the inlet pressure is 320 mmHg; the output pressure after the first stage is 0.8 MPa, the inlet pressure at the third stage is 0.5 MPa; the methanol output pressure at the fifth stage is 12.5 MPa, and the synthesis gas output pressure at the sixth stage is 24 MPa. What is the pressure when no Roots blower is used? When the gas generation volume is unstable, the gas holder fluctuates up and down; does the pressure stabilize once it is generated? Can the production conditions be stabilized? This post was last edited by Xiaoyao Wuming on 2009-4-3 22:37.]

What is the pressure when no Roots blower is used? When the gas generation volume is unstable, the gas holder fluctuates up and down; does the pressure stabilize once it is generated? Can the production conditions be stabilized? ----------------------------------------- What you said is all correct; gas tanks are indeed designed to serve as a buffer. Is the inlet pressure of the Roots blower stable? It works on the same principle as a compressor. There is also the issue of the coordination between the Roots blower and the compressor.

Our plant produces ammonia via natural gas synthesis, using centrifugal compressors with two cylinders and three compression stages; the design pressure at the inlet is 2.51 MPa, while the design pressure at the outlet is 14.432 MPa. The compression ratio is calculated based on the cube root of the pressure difference between the inlet and outlet of the compressor. Generally, 1.2 to 2.5 is used.

We are using my reciprocating compressor, with two cylinders and three compression stages; the inlet pressure is 3.0 MPa, the first outlet pressure is 8.6 MPa, the second outlet pressure is 15.2 MPa, and the third outlet pressure is 32.0 MPa.

We are also using a reciprocating compressor, of the four-cylinder, three-stage compression with symmetric balance design. The inlet pressure is 3.0 MPa, the first outlet pressure is 8.62 MPa, the second outlet pressure is 17.2 MPa, and the third outlet pressure is 31.4 MPa. The compression ratios are 2.8, 2.0, and 1.9 respectively.

The processes vary from factory to factory, and so does the number of compression stages. For example, in a typical six-stage compression system: the inlet pressure is 300 mmHg, while the outlet pressure is 0.2 MPa at the first stage, 0.8 MPa at the second stage, 2.1 MPa at the third stage, 5.0 MPa at the fourth stage, 13.0 MPa at the fifth stage, and 32.0 MPa at the sixth stage. The pressure ratio between the single-stage outlet and inlet of the compressor is called the compression ratio, which is generally kept below 4.

Here, it’s four-stage compression: absolute pressure of 3.0 ~ ~14.53 ~15.34

The ratio of the single-stage outlet pressure to the inlet pressure is known as the compression ratio for that stage, which generally ranges from 1.5 to 3.0. If it is too small, it is difficult to meet the process pressure requirements, and more compression stages are needed; if it is too large, it is hard to dissipate the large amount of heat generated during compression, which imposes higher demands on the material used for the equipment. The typical pressures at various stages of the hydrogen-nitrogen compressor (maximum allowable gauge pressure, in MPa) are as follows: inlet 1: 0.04; outlet 1: 0.32; inlet 2: 0.32; outlet 2 (conversion): 0.9; inlet 3 (pressure swing adsorption): 0.8; outlet 3 (pressure swing adsorption): 1.75; inlet 4 (methanation): 1.75; outlet 4: 4.5; inlet 5: 4.5; outlet 5: 12.5; inlet 6: 12.5; outlet 6 (synthesis): 30

Ours is a centrifugal compressor, with an inlet pressure of 4.51 MPa, a pressure in the compression stage of 10.608 MPa, and an outlet pressure of 11.49 MPa. The compression ratio is 2.5. However, due to differences in the process, the corresponding pressures vary.