Please discuss whether atomized dry gas has an impact on catalyst loss
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Gentlemen, our catalyst device has been suffering from severe wear and tear; the specific consumption is around 1.4. There is a high amount of dust in the flue gas exiting the chimney, and the solid content in the slurry in the distillation system is as high as 0.9%. After conducting some parameter analysis, it was found that the amount of atomized dry gas used was much higher than before – 2 tons per hour – with 5 tons per hour of steam being used. Once we stopped using atomized dry gas, the problem of catalyst wear and tear was resolved. It is initially suspected that the temperature resulting from the mixing of the two gases will be below the steam saturation temperature, causing the steam to condense and carry water with it; this water then enters the lift pipe and leads to the fragmentation of the catalyst. After calculation, the temperature after mixing is 180 degrees. Our steam partial pressure is 5.27 kg of pressure (absolute pressure); at this pressure, the saturated temperature of steam is 154 degrees, so there should be no water present. As for the wear caused by the linear velocity of the nozzle, I haven’t calculated it; may I ask how everyone calculates the linear velocity of the nozzle? ? ? We later tried to use atomized dry gas again, but this time in smaller quantities, at 735 kg/h. A few days later, we found that the solid content in the slurry had increased, rising from 0.1% to 0.5%. However, there were no obvious changes in the chimney, so we promptly stopped using the atomized dry gas. Has the solid content of the slurry also decreased? ? ? ? (When calculating the mixed temperature, specific heat is used for the calculation; since no suitable formula was found, enthalpy change is not utilized.) ) Could everyone please analyze this? ? ? ? This post was last edited by mxtao123 on 2009-4-1 06:35.]
Is nebulization done using both dry gas and steam?
Is your dry gas used for atomization or for stripping? Is there any significant change in the precipitator pressure when using atomized dry gas versus atomized steam?
The temperature difference is only 26 degrees; considering the effects of mass and heat transfer resistances as well as calculation errors, could there be a liquid phase present in certain areas?
Dry gas is used for atomization; I haven’t seen that done before. It’s difficult to determine the cause based on the observed phenomena, but I suggest analyzing it by examining the sieve analysis composition of the catalyst. If the catalyst is flushed out during dry gas regeneration reactions, and there is a large amount of fine powder smaller than 40 microns in the sieve fraction, it is possible that the issue lies with the dry gas, which causes an excessively high nozzle linear velocity leading to catalyst fragmentation or thermal breakdown. But this phenomenon is quite extreme and difficult to occur. It is necessary to observe whether the frequency of catalyst loss is associated with certain operations in order to rule out random factors. A significant loss of catalyst is most likely due to some organic changes, though these changes are relatively subtle; it’s usually possible to detect them as soon as inspection is carried out after the plant is shut down.
In our system, dry gas is mixed with steam and fed into the feed nozzle for atomization, which resulted in catalyst loss; ever since we started using atomized dry gas, the catalyst no longer leaks away. What could be the reason for this? At first, it was thought that the nozzle linear speed was too high, but that doesn’t seem plausible either.
I’ve heard of dry gas atomization for the first time. However, the low temperature and low pressure of dry gas, combined with mixing it with steam, affect the atomization effect, which in turn impacts the line speed; if there are problems with the centrifugal separation, then the material will leak out