How is the PSA time coefficient calculated?
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Recently, in order to adjust the pressure in the hydrogen pipeline network and the fuel gas pipeline network, the plant’s scheduling team asked us to adjust the PSA time coefficient. A higher time coefficient results in more hydrogen production; conversely, a lower coefficient leads to more purge gas being produced. However, I still don’t quite understand how this time coefficient is calculated—is there some kind of formula for it? I hope experts can help explain this to me. Thank you
It seems you’re referring to the scheduling and matching process in factories. Logically, there should be a hydrogen storage buffer system between hydrogen production and consumption in such facilities. If the hydrogen produced is used immediately, it becomes difficult to achieve proper coordination; for example, if the hydrogen demand by the hydrogenation system is not constant, the hydrogen pressure in the pipeline will drop during peak usage times, resulting in a shortage of hydrogen, or vice versa. For most hydrogen production processes, it is almost impossible to make timely load adjustments; adjusting the PSA operation time is a common practice in many plants, but such actions lead to increased hydrogen production costs. To adjust the operating time of PSA, it is necessary to identify patterns during factory operation; the hydrogen production load is determined based on the maximum hydrogen consumption. During periods of low hydrogen usage, the operating time of PSA is reduced, which leads to a decrease in the amount of hydrogen produced by PSA. As a result, the hydrogen yield is lower, and any excess hydrogen is discharged as off-gas. Calculate the hydrogen production amount corresponding to the adjusted PSA runtime, and for the next adjustment, simply set the PSA operation time. It can only be this kind of simple and brute-force control method.