Regarding the configuration of the PSA hydrogen production process

Our plant produces CO using PSA after low-pressure methane separation at 5.5 Mpa; the operating pressure is 5.2, and this pressure can be adjusted accordingly as per the load. Under high load conditions, the hydrogen-rich gas can be sent directly to the synthesis process. Analytical gas can be used as fuel gas for combustion. Hydrogen production should also be no problem; CO can be pressurized and sent for synthesis

For high-pressure PSA, there is only one company in China that has successful implementation of this technology. The yield depends on the design of the process flow – whether the PSA unit operates under vacuum or under purge conditions. A vacuum-based process yields higher results, but it requires larger investments. However, after the gas analyzed in the vacuum process enters the compressor, it can be utilized in a wider range of ways.

You’re referring to our factory; it seems you know quite a lot about our manufacturing processes. Our analytical gas has been fed into the fan, but due to unstable inlet gas flow, the current fluctuates greatly after it is put into operation; it still hasn’t started working. The analytical gas-fed acetylene plant was used as a fuel gas source

Perhaps you’ve misunderstood me; I said that there is only one valve manufacturer that offers high-pressure PSA systems, but I’m aware of several companies that do provide such systems. Nowadays, with water-coal slurry gasification, using high-pressure PSA units under the high pressures present in the gasification island is a great option, as it helps to reduce investment costs and energy consumption. The analyzable gas thing always fluctuates. My system is a purging process, not a vacuum process; my furnace can handle such fluctuations. As for your vacuum process, it mainly involves measures such as overpressure protection through timely venting, and maintaining a stable flow rate at the outlet and inlet when pressure is low. This depends on the design; if the design is poor, it can be quite troublesome for the gas compressor. Personally, I think from a technical standpoint, it’s not a problem.

Our plant produces methanol and ethylene glycol from coal; hydrogen is produced using a purification process with a pressure of 5.6, along with 3.5 PSA, and a purge process is employed, with a purge gas concentration of 0.025, which is then sent to the methanol production unit. The inlet pressure fluctuates greatly, the operation time is short, and no other issues have been detected yet

A 5.6MP purification system is more than sufficient to pair with a 5.0MP PSA hydrogen production unit; using a 3.5MP system would be a waste. I can reach 15 KP in terms of analyzed gas; the key is to have a negative-pressure furnace for burning it. If there is no negative-pressure furnace, one can only use a compressor to increase pressure; in this case, the design of the compressor needs to be carefully considered.

Gaseous methanol at 25 kPa can’t be used either; this gas contains relatively high levels of CO and H2, so it can be used as fuel gas

PSA with a low pressure of 4.0 MPa and a subsequent pressure of 3.4 MPa – H2 purity of over 99.9%, meeting the requirements of subsequent processes; a purging process is used, and the recovered gas is recycled to the previous stage, resulting in an overall yield of over 99%.

Later, a gas compressor is used for compression, raising the pressure to around 5.6 MPA before sending it to the synthesis process.

The hydrogen pressure required in the subsequent process is at the 3.0 level, so this level was chosen during the design phase.