Does long-term steam exposure have an impact on high-activity catalysts?
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We are using the B113 type ferro-chromium catalyst produced by Xinxiang Bai Dai Company. Due to issues with the subsequent system, our conversion system has been fed with steam for about 20 days now; the temperature in the first stage of the reactor is around 300 degrees, while that in the second stage is around 250 degrees. I would like to ask those of you who have experience in this field: could feeding steam to the catalyst over such a long period of time have an impact on it, and if so, to what extent? Please share your insights.
Isn’t transforming normal production also done by using steam? Does that mean the amount of steam used is higher than normal? In such a case, it may affect the low-temperature catalyst (causing sulfur release), and it may also lead to pulverization of the medium-temperature catalyst.
This post was last edited by *aoye613 on 2009-9-1 21:26. For low-temperature operation, nitrogen is used for pressure maintenance, while for high-temperature operation steam is used for this purpose; steam is applied for an extended period of time without using gas. Will this have an impact on the catalyst?
As the original poster mentioned, this situation is very likely to cause the catalyst to become pulverized.
Generally speaking, exposing a medium-temperature catalyst to steam for an extended period has no positive effect on its activity; mainly, since no chemical reactions take place, the temperature of the catalyst tends to decrease over time； The catalyst becomes increasingly wet; heating must be done slowly, otherwise the water turns into steam and the volume expansion can cause severe damage, leading to high resistance ； The wall temperature of the converter becomes increasingly lower, and the moisture content in the furnace walls also rises. Care must be taken when raising the temperature during operation; otherwise, the insulation of the furnace walls will be damaged, resulting in significant losses ； In medium-temperature converters, steam is continuously supplied, and regular drainage is necessary to prevent the accumulation of condensate water, which could harm the catalyst ； During long periods of idling with a low-temperature catalyst, it is not only impossible to supply steam; moreover, dry gas must be used to blow through the catalyst during this idling period, in order to prevent a drop in temperature that could lead to condensation and have a significant impact on the catalyst’s activity at low temperatures.
Be careful to prevent condensate after temperature drops from damaging the catalyst! Also, pay attention to the quality of steam to avoid catalyst poisoning!