Copy a section of work notes regarding the relationship between the H2 concentration at the outlet and the inlet pressure in membrane separation

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This post was last edited by Small and on 2017-9-12 at 20:31. In the units currently in operation, the adjustment of the membrane separation process depends on the adjustment of the synthesis pressure; during each shift, this is done by closing the FIC1307B valve, thereby reducing the inlet pressure of the membrane separation unit while keeping the outlet pressure relatively constant. This approach overlooks one factor: the principle behind hydrogen recovery using membrane separation is to utilize pressure differences to drive gases of various components, and gas separation is achieved through their different permeabilities and flow rates. The greater the pressure difference between the inlet and outlet, the higher the recovery rate. Hydrogen is a fast gas that accumulates on the low-pressure side of the membrane outlet, while other gases such as methane are slow gases that accumulate on the high-pressure side. This results in a decrease in the hydrogen concentration at the membrane outlet. If the system load decreases further and the hydrogen from the membrane outlet is used in a new system for ammonia synthesis, it is possible that the hydrogen will not meet the required standards.