PSA hydrogen production
Thread Content
Dear everyone: In the PSA hydrogen production process used in refining or coal chemical projects, what are the approximate inlet and exhaust pressures of the purge gas and hydrogen compressors? Thank you!
For your reference, our PSA parameters are as follows: the desorption gas pressure is not high, generally ranging between 20-40 kPa； The inlet pressure of the hydrogen compressor is around 1.5 MPa, while the outlet pressure depends on the pressure in the subsequent stage
Thank you, expert. Is a PSA unit necessarily required in continuous reforming within oil refining?
Generally, hydrogen requires a purity of over 99.99%, for which a PSA unit is needed
I don’t know much about the gas industry; I only worked on safety assessment tasks at a gas plant for two months. The hydrogen is produced through methanol pressure swing adsorption, and the inlet pressure of the hydrogen compressor can be adjusted using the PSA unit, while the outlet pressure varies depending on the requirements of the subsequent containers (torpedo tanks, cylinders). Typically, the capacity of these cylinders is 130 kilograms. The purity of hydrogen is controlled at four 9s; five 9s represents high-purity hydrogen.
For hydrogen production using natural gas here, the pressure of the gas subjected to PSA separation is maintained at 0.04 MPa; the inlet pressure of the compressor is around 0.7 MPa, while the exhaust pressure is around 2.4 MPa!
The hydrogen pressure is primarily determined by the back end; what is decided there affects what happens at the front end. The inlet pressure of the gas release compressor is generally kept around 20 KPa(G), as this is the level typical for water ring vacuum pumps.
The intake pressure of 07 MPa and the exhaust pressure of 2.4 MPa you mentioned should refer to the pressures of the hydrogen compressor, not those of the purified gas, right?
The difference is significant, depending on the process. . . .
This depends on the specific process; the pressure of hydrogen is generally similar to the pressure of the gas fed in, and only the system resistance of the PSA unit needs to be taken into account. However, the pressure of the desorbed gas varies significantly depending on factors such as the gas composition and the adsorbent used.