Question: How can the purge gas from hydrogen PSA be utilized?
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Seeking help: My company plans to install a hydrogen PSA adsorption unit that will produce approximately 350 standard cubic feet per hour of desorbed gas, with hydrogen accounting for 74% of its composition, and methane making up the rest. We want to use it as fuel for combustion, but are concerned that the high hydrogen content requires modifications to the nozzles of the heating furnace, and whether there are higher risks such as flashback during combustion? I would like to ask those of you who are familiar with such processes: what are the possible ways to recycle this type of gas? What are the things to keep in mind when using it as fuel?
Our desorbed gas is directly fed into the heat transfer oil furnace for combustion; the burner in that furnace is designed for mixed combustion of oil and gas
How can the exhaust gas contain 74% hydrogen? Whether the heating furnace backfires or not has nothing to do with the hydrogen content in the fuel gas; as long as it’s a gas burner, no changes are needed and it will burn just the same
A 74% H2 content is a waste when used as fuel; although H2 has a high combustion temperature, its calorific value is not high, so it is recommended to recover the hydrogen.
What type of hydrogen production device do you have? Hydrogen can be burned as long as the oxygen content does not exceed the limit, and it is sufficient to maintain a positive pressure in the pipelines
The hydrogen content in the desorbed gas is too high. While ensuring that the hydrogen level in the final product remains within acceptable limits, the adsorption time should be adjusted to reduce the hydrogen content in the desorbed gas; it is generally required that this level stay below 42%
The users require a high level of purity; the analysis of the solutions provided by several manufacturers shows that the hydrogen content in the gas is quite high, with none being below 60%
Can 99.99 meet the requirements? Either there is a problem with your PSA adsorbent
The hydrogen content in the gas is 74%, with the remainder being methane. I would like to ask about the source of your feed gas? In our factory, the desorbed gas generated during hydrogen production is sent directly to the conversion furnace for use. If it’s not possible to increase the hydrogen recovery rate by adjusting the adsorption time, then vacuum pressure swing adsorption can be used to achieve this, so that the hydrogen content in the desorbed gas does not remain too high
Where is your PSA from? The hydrogen purity in the desorbed gas is so high that the hydrogen recovery rate is quite low. It is possible to consider recovering it and burning it as fuel gas, but it is necessary to check whether the pressure of the desorbed gas can reach that of the fuel gas A reciprocating press could be considered