Analysis of the reasons for uneven temperature distribution in the methanol synthesis catalyst bed
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The catalyst is C307; the unit starts and stops frequently, and it has been in use for over 4 years. What are the reasons for the large temperature differences in the longitudinal and transverse directions of the catalyst bed thermometer? ?
The lateral temperature is primarily used to detect whether there is a flow deviation in the catalyst, while the longitudinal temperature is mainly used to measure the temperature rise across the entire bed!
The H/C ratio of the gas entering the tower is too low, resulting in increased side reactions.
Consulted the manufacturer, who recommended using the catalyst for a long period to avoid a decline in its activity； The difference in gas composition is due to a low hydrogen-to-carbon ratio. As for what those masters mentioned above said, it is also impossible to verify.
How come, in my view, the CO2 content is over 20%?
Due to its long service life, the catalyst is at the end of its operational life. On one hand, the lower activity of some of the catalysts leads to uneven reactions and large temperature differences; on the other hand, local caking of the catalyst can occur, resulting in uneven temperature distribution due to uneven flow.
The gas composition is severely imbalanced; let’s check a few sets of fresh gas components
During the final stage of operation of the catalyst, some of it becomes inactive, resulting in an increase in carbon content in the loop!
Your hydrogen-to-carbon ratio is even lower than the theoretical value; how can you operate in such conditions? The conversion and decarburization processes are not working properly. The temperature difference in the radial direction is caused by caking of the catalyst in certain areas, which results in insufficient gas flow. As for the longitudinal temperature difference, you’re referring to the large gap between the temperature at the top and that at the bottom, right? By checking those temperatures, it’s possible to determine which layer of catalyst has lost its activity