Method for controlling off-gas pressure from off-gas tank in three-column PSA system for hydrogen purification

摘要

PROBLEM TO BE SOLVED: To stabilize the combustion of the burner of the reformer using off-gas by suppressing the pressure fluctuation of the off-gas from the off-gas tank that is attached to the three-column type PSA unit for hydrogen purification. SOLUTION: In the control of the off-gas from the off-gas tank attached to the three-column type PSA unit for hydrogen purification, the opening degree of the off-gas flow rate-controlling valve is increased or decreased in a prescribed small step on the basis of the minimum pressure at which the pressure of the off-gas tank becomes minimum, when the off-gas in the off-gas tank is fed to the burner for the hydrogen production reformer.