Casali synthesis tower
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What causes the large temperature difference between the left and right sides of the catalyst bed in the Cassali reactor?
Local pulverization and caking of the catalyst lead to gas flow deviation, as well as unreasonable opening degrees of the cold line control valves
First, check if there is a problem with the thermocouple. Whether the catalyst is poisoned, whether uneven packing causes flow bias, and whether damage to the internal components allows cold air to enter the top of the bed. Any of these is possible.
Is the opening degree of the cold bypass lines for bed 1 and bed 2 unreasonable?
It is likely a design flaw; in particular, the temperature of the bed layer at the uppermost inlet area is an issue. In Casali synthesis, large temperature differences within the bed layer are common, with differences of up to around 20°C. At present, the staff at Casali themselves are unable to explain this phenomenon.
The internal components of the Casali should be fairly mature by now, so there shouldn’t be any major issues. Could it be that the design has been improved?
We are also in Casale; the temperature difference across the hot spot plane on the first floor is 20 degrees as well
For troubleshooting temperature deviations, you can check each item one by one: the auxiliary line switch (including verifying the opening degree of the valve), the service life of the catalyst (problems such as caking or improper packing), issues with the thermometer, damage to internal components, and so on
It’s the same here in Casale too–the temperature difference on the first floor is over 30°C; at times it even reaches over 50°C. We have taken all possible factors into account. It’s been in use for three years, but temperature differences started appearing after just over a year. On several occasions, when the temperature rose, the temperature on the first floor hadn’t yet increased while the temperature on the second floor soared already; before the first floor reached 380°C, the second floor required cooling to prevent its temperature from rising further~
It’s the same here in Casale too–the temperature difference on the first floor is over 30°C; at times it even reaches over 50°C. We have taken all possible factors into account. It’s been in use for three years, but temperature differences started appearing after just over a year. On several occasions, when the temperature rose, the temperature on the first floor hadn’t yet increased while the temperature on the second floor soared already; before the first floor reached 380°C, the second floor required cooling to prevent its temperature from rising further~