PSA9 tower in operation

When changing from 10 towers in operation to 9 towers, it changes from 10-2-4 to 9-2-3; the number of voltage equalization operations is 3. Since there is one fewer voltage equalization operation, the time required for T4 needs to be reduced, and this must be reset in the program for 9 towers in operation.

When the operation mode is changed from 10 towers to 9 towers, it changes from 10-2-4 to 9-2-4; the number of pressure equalization cycles remains at 4, and the time for T4 stays the same. In the 9-tower operation mode, since the number of pressure equalization cycles does not change, the hydrogen production capacity remains unchanged. However, due to limitations in adsorption capacity, the efficiency of hydrogen production decreases by about 12%

Since the PSA hydrogen purification unit is composed of 10 adsorption towers. Therefore, to improve the reliability of the device, a set of automatic tower switching and recovery procedures has also been developed for it. In other words, when one adsorption tower fails, it can be taken out of service, allowing the remaining 9 adsorption towers to operate in a 9-2-5 configuration. If another adsorption tower fails, it can also be removed, and the system will then switch to the 8-2-4, 7-2-3, 6-2-2, and 5-1-2 configurations in sequence. But at this point, parameters such as the gas processing capacity and hydrogen production rate of the device will change. Process, Total number of adsorption beds, Number of adsorption beds in operation, Number of pressure equalization cycles, Nominal treatment capacity, Hydrogen production volume: 10-2-6: 10, 2, 6; 60,000; 51,790. 9-2-5: 9, 2, 5; 60,000; 50,800. 8-2-4: 8, 2, 4; 60,000; 49,700. 7-2-3: 7, 2, 3; 60,000; 47,800. 6-2-2: 6, 2, 2; 60,000; 45,500. 5-2-2: 5, 1, 2; 30,000; 22,700. Since the PSA hydrogen purification unit consists of 10 adsorption towers. Therefore, to improve the reliability of the device, a set of “automatic/manual” tower switching and recovery procedures has also been developed for this device. In other words, when one adsorption tower fails, it can be taken out of service, allowing the remaining 9 adsorption towers to operate in a 9-2-3 configuration. If another adsorption tower fails, it can also be removed, and the system can then switch to 8-2-3, 7-2-2, 6-1-2, or 5-1-2 configurations. At this point, the purity criteria of the device’s output can still remain unchanged, but the device’s processing capacity and hydrogen recovery rate will decrease. The changes in the parameters of the device after cutting are as follows: Process, Total number of adsorption beds, Number of adsorption beds in operation, Number of pressure equalization cycles, Hydrogen production rate (Nm3/h): 9-2-3: 9, 2, 3, 100000; 8-2-3: 8, 2, 3, 80000; 7-2-2: 7, 2, 2, 80000; 6-1-2: 6, 1, 2, 60000; 5-1-2: 5, 1, 2, 50000. It’s not the case that one layer remains unchanged; this depends on the design

What’s the use of constantly remembering T1, T2, T3, T4? The key is to understand PSA; once you know what to do at each stage of T1, T2, T3, T4, you’ll know how to make adjustments. Is the time required for 3 pressure equalization steps the same as that for 4? First carry out the pressure equalization, then adjust the desorption time – avoid wasting time. Switch over as soon as all the pressure curves start to level out, so that the PSA efficiency can be maximized. If you figure out why the hydrogen recovery rate drops when the voltage equalization is reduced by one time, you will be able to make the necessary adjustments as well. Look at the valve switch gauge; it’s better than reading any book. Looking at valve switching in DCS, the results are better.

It is likely that the number of adsorption towers has not decreased, which is why the processing load has not gone down. It has little to do with the number of voltage equalization attempts.