METHOD OF CONTROLLING PRESSURE OF OFFGAS FROM OFFGAS TANK IN FOUR TOWER-TYPE PSA EQUIPMENT FOR PURIFYING HYDROGEN

摘要

PROBLEM TO BE SOLVED: To suppress the fluctuation of the inner pressure of an offgas tank and to stabilize the combustion state of a burner when the offgas is supplied as a fuel of the combustion part of a reformer, in a four tower-type pressure- swing adsorption(PSA) equipment for purifying hydrogen. SOLUTION: The method of controlling the pressure of offgas from the offgas tanke is characterized in that, when offgas of the offgas tank provided in the four tower-type PSA equipment for purifying hydrogen is supplied to the burner of the reformer for hydrogen production, the pressure of the offgas from the offgas tank is controlled by increasing or lowering the opening degree of a valve for controlling the flow rate of the offgas with a predetermined small degree while setting the minimum pressure at which the pressure of the offgas becomes minimum as a standard, which valve is provided on the downstream side from the offgas tank.