Is the cause of fouling in the flue extractor related to the phosphorus content in the catalyst?
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Is the cause of fouling in the flue gas extractor related to the phosphorus content in the catalyst? Please reply. This post was last edited by DAC The army rules the world on 2008-9-16 21:37.]
According to the information provided, the cause of fouling in the flue gas extractor is related to the phosphorus content in the catalyst
Phosphorus in catalytic cracking catalysts primarily serves to regulate the hardness of the catalyst, which is related to the catalyst’s wear index. If two different catalysts are used simultaneously, they will wear against each other, generating a large amount of fine powder that can cause scaling in the flue gas equipment. When only one type of catalyst is used, its hardness is low, and more fine powder is generated during use, which in turn affects the operation of the flue gas treatment system.
The impact of fine powder is quite significant; such problems have occurred before
I can say with certainty that a high P content in the catalyst, combined with a high Ca content in the raw materials, will definitely lead to scaling in areas where high speeds and large amounts of fine powder are present, such as in triple spinners and flue gas desulfurization units. I have seen several such installations, and I have experienced scaling occurring as a result of an increase in Ca content in the raw materials and a rise in P content in the catalyst. Especially with dehydroolefins catalysts, the P in them tends to cause scaling; there’s no doubt about that. This issue has been debated for a long time, and catalyst manufacturers are very reluctant to accept this conclusion.
The pressure of the cooling steam for the smoke extractor wheel disc can also cause scaling on the compressor blades. A pressure measurement point is installed inside the sealing area of the first and second stages of the rotor (i.e., in the dead space) and outside it (at the top of the second-stage static blades). The pressures at these two points are fed into a differential transmitter, which then sends the signal to a differential pressure regulator. The output of this regulator controls the steam control valve, ensuring that the pressure in the dead space remains always higher than the pressure at the second-stage static blades.
There is no clear conclusion yet. Fouling of the flue gas extractor is related to factors such as the catalyst, plant operation, operating conditions of the three spinners, and the condition of the equipment; the main causes may vary depending on the specific plant.