Regarding the first baking of the FCC unit, is it necessary to maintain a constant temperature of 315 degrees?
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As the title suggests: Generally, the temperature is raised from room temperature to around 150°C to drive out moisture; at around 150°C, the surface water is removed. The temperature is then increased from 150°C to 315°C to remove the crystalline water contained in the lining, and further raised from 315°C to 540°C for sintering of the lining. Or should the temperature be kept constant at 350°C? ?
150 315 540 is just a rough range; it’s best to ask the manufacturer of the lining for specific details! They have quite a lot of experience!
This post was last edited by qlalong on 2012-2-12 at 18:10. To ensure the long-term operation of the device, it is necessary to go through the three temperature stabilization phases of 150, 315, and 500 degrees. The minimum duration for each temperature stabilization phase should be 24 hours; if time permits, it is advisable to maintain that temperature for 48 hours, so that the lining can function properly over a long period of time.
We have three constant temperature stages: 150, 315, and 540, with each stage maintaining a constant temperature for 24 hours
Since the original poster already knows that the three stages have different meanings, why do they still have such doubts? Imagine that if the temperature is not maintained at around 150 degrees, or if the time spent at that temperature is insufficient, residual surface water will enter the 350-degree stage where crystallization occurs. At this stage, it is necessary to remove both the surface water and the crystallized water; moreover, surface water vaporizes much more quickly than crystallized water. If this water is not removed at low temperatures, its rapid vaporization at 350 degrees can lead to a situation similar to a catalyst’s \"thermal collapse\", which can directly damage the lining. Therefore, each stage must be carried out step by step according to its specific meaning; it is not possible to skip any step. As for the exact temperature required, this depends on the lining material, so it is best to consult the manufacturer directly. This is just my personal opinion; if there are any mistakes, please feel free to point them out
What I mean is: is it possible to cancel the 315-degree constant temperature setting and go straight to a 350-degree constant temperature setting?； The temperatures at 150 and 540 degrees remain constant
This post was last edited by qlalong on 2012-2-20 at 13:36. The key is to consider the material requirements of the lining; if 350 degrees can achieve the desired effect, then it’s possible to use 350 degrees for maintaining a constant temperature.
The original poster did not mention the 350-degree stage in their question; perhaps they got confused by information from other sources. Whether it is 315 or 350 depends on the specific materials used for the linings of the two components in each setup, and this information is provided by the supplier. It’s not possible to simply choose 315 degrees or 350 degrees as one wishes. Although there are three stages, if baking is not carried out according to the temperature curve specified by the manufacturer, the desired results will not be achieved. A slight deviation is acceptable, but not as you might think; you can simply choose any three constant temperature points and use them for drying.
Generally, there are three stages: 150°C, 315°C, and 500°C, and the temperature must remain constant at each of these levels. If possible, maintain a temperature of 315°C for 48 hours; for other temperatures, 24 hours is sufficient.
Our facility requires a constant temperature at specified levels, stage by stage. In my opinion, when the temperature reaches 500 degrees on March 15th, if the rate of increase is high, a small amount of moisture could cause the lining to crack, leading to fissures.
150°C, removal of free water； 320°C, removal of crystalline water ； Sintering at 500°C with refractory mortar. Each dehydration step should be maintained at a constant temperature for 24 hours, and the rate of temperature increase should generally not exceed 30°C/h.