The issue of excessive moisture in aniline distillation.
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A few days ago, the moisture level in my aniline distillation process was too high. After shutting down the plant, I checked the pressure in all the circulating water systems and reboilers – everything was fine. Once operations resumed, the moisture level returned to normal; it was all a waste of time. Please help me analyze the reasons.
There are many reasons why the moisture level exceeds the specified limit in this case. Possible causes include: 1. The initial product in the tank contains a high amount of moisture, which makes it more difficult to handle (when there isn’t much initial product in the tank, failing to switch to another storage tank in time can lead to an excessive moisture level in the final product during that period)； 2. It is also very likely that excessive moisture in the finished product will occur if the process parameters of the initial distillation tower are not within the specified range ； 3 If sampling takes place on a rainy day, it is very likely that the moisture content of the sample will exceed the standard ； Additionally, incorrect analysis can also lead to inaccurate results ； 4. A dirty packing in the initial distillation tower can also cause excessive moisture levels. By the way, I would like to ask the original poster how long this issue of excessive moisture has persisted? How often should samples be taken for analysis when moisture levels are abnormal? Were samples taken at those points?
I found the cause – there’s a leak in the tube sheet of the reboiler in the distillation tower!
Isn’t the reboiler made of stainless steel? Tube sheet leaks are rare in aniline plants. What is the production capacity of your facility?
Otherwise, how could there be a leak with such a thick tube sheet?
The catalyst in the tar can cause wear on the tube sheet welds
There is a small leak at the weld joint between the tube sheet and the tubes!
Wow! Is your process liquid-phase hydrogenation or gas-phase hydrogenation, and what is the diameter of the fluidized bed?
My device has only been in use for a year and a half – won’t it suffer wear and leakage due to the catalysts in the tar? Have you ever encountered a situation where the catalyst wore out and leaked?