The methanol cracking hydrogen production process is not operating properly; I seek guidance from experts

We employed the methanol and water wet reduction method, took samples of the converted gas for analysis, and confirmed that the purity of hydrogen in the converted gas remained unchanged and no hydrogen was consumed during the reduction process, after which the reduction was terminated

This post was last edited by Yimi Yangguang1234 on 2017-10-6 at 21:59. None

1. Deactivation due to a lack of catalyst again; check methanol S, P, Cl, as well as the conductivity of the desalinated water. 2. Has the pressure difference at the inlet and outlet of the converter been measured? Severe catalyst pulverization can also prevent an increase in load. 3. Try reducing the load; if it operates normally, then the amount of catalyst loaded is too low. It’s possible that it wasn’t operated at full load before, and it’s also possible that the converter was designed to be too small~~

This post was last edited by Yimi Yangguang1234 on 2017-10-6 at 21:58. None

The volume of catalyst filled in the converter is 1.474 cubic units; the catalyst used is type F104, with a bulk density of 1.35. I would appreciate guidance from those with more experience – could there be issues in the design provided by the design team? Everything seemed normal when the load was around 70%, with normal temperatures both at the top and bottom of the converter as well as a normal methanol conversion rate; however, problems arose once the load was increased

Does the load decrease and do the indicators return to normal?

By reducing the load, the temperature at the lower part can increase a bit, which improves the performance; however, the methanol content in the condensate remains the same with little change

At full capacity, what are the yield and purity?

There are always 2 sets; each set can operate at full load with a PSA purity level of over 4 nines. After the installation was completed and the system was put into operation, I monitored it for 72 hours at full load, and the inspection showed no issues – everything was normal! After that, the operation was carried out at a reduced load of 400 for some time; once the load was increased to over 500, the performance gradually deteriorated. Both sets had their catalysts replaced at some point; for one set, the bulk density was set too low to around 1.1, resulting in only 1.8 T of catalyst being used. The same problem occurred there as well – performance deteriorated once a load of 500 was applied ； The second set of catalysts contained 1.92 T of material; it was operated at a load of over 500 for 1 month, after which the methanol content in the condensate reached around 10%, and the situation deteriorated further over time. This time, the installation was out of service for 2 years; thereafter it was overhauled and the heat transfer oil, catalyst, and adsorbent were replaced. In the past, the catalyst would turn to powder after being unloaded; it would break apart at the slightest pressure. It seems that water got into it, and I guess this was due to the lack of nitrogen protection during the shutdown period. During this maintenance work, 1.96 T of catalyst was installed per set. The original plan was to use 2 T; there is still 1 bucket of catalyst weighing 40 kilograms unused per set. The first set operated at a low load of 400 hydrogen production for over 6 months without any issues, but performance began to deteriorate after the load was increased to around 540. The second set is the situation described in the first post. The methane cracking unit has been malfunctioning all along, while the pressure swing adsorption system is working normally. I have also suspected that there are flaws in the design process of the converter; the amount specified in the design is not sufficient to meet the actual requirement of producing 600 units of hydrogen. I have also looked into the relationship between the amount of catalyst used by other manufacturers and the hydrogen production volume – how much hydrogen is produced by a 2T catalyst – and why, at higher loads, the temperature at the upper part of the converter is higher than that at the lower part. Please help guide me