Temperature issue of the first-stage catalyst in the second set of sulfuric acid production unit at Anhui Xinzhongyuan
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This post was last edited by melao on 2011-11-16 09:15. This set of equipment has been in chemical trial operation since September this year, and now this issue has arisen: the temperature at the outlet of one section of the catalyst is getting lower as the operation time increases. Every time the plant is shut down, the conversion fan does not need to be stopped immediately. If you let it run for a while before turning it off and then start driving again, its temperature will quickly return to normal, but over time the same problem as before will occur. I would appreciate some guidance from an expert. Thank you
Try lowering the gas concentration a bit and see what happens
Reply to 1# wmyp2007: There are two reasons – one is that the concentration of sulfur dioxide converted during production is too high, and the other is catalyst poisoning
Its sulfur dioxide concentration is only between 8.0 and 9.0
The original poster didn’t clarify the question! Tell me how you park your cars and how you drive This makes it easier for everyone to analyze.
Reply to 1# wmyp2007: It seems that the catalyst at the bottom has experienced excessive temperatures, which has led to a decrease in its activity, or perhaps the catalyst itself does not have good high-temperature resistance. But the original poster didn’t clarify the question. It’s best to list the data and such, as this will help everyone analyze and make judgments.
It seems to be due to insufficient oxygen levels.
The situation isn’t very clear; it’s hard to say whether it’s the catalyst or a low oxygen content along with high gas levels – other factors such as temperature also need to be considered.
Indeed, it’s not easy to say exactly; low oxygen levels indicate a problem with the sulfur dioxide concentration. With online monitors, calibration using standard gases can easily lead to errors, while manual analysis results in large inaccuracies. When the system is shut down, whether cold air or hot air is used to blow out the gas from the converter, or if no air is used at all, the temperature of the outlet section will drop rapidly. However, this does not reflect the actual temperature of the catalyst layer after the system is shut down. As long as the insulation is effective, the temperature inside the catalyst layer tends to drop slowly, with a typical rate of decline of no more than 5 degrees per hour. It depends on the insulation effect.
The original poster didn’t explain things clearly enough. It’s best to list the data and such, as this will help everyone analyze and make judgments. Based on what the original poster said, it seems that the oxygen-sulfur ratio wasn’t controlled properly.
Our company was in a similar situation to yours some time ago; later, we brought in catalyst experts for guidance, as the catalyst casing was covered by red acidic mist. At high temperatures, it wraps around the catalyst, reducing its activity; it falls off naturally once cooled down. Then the catalyst needs to be screened.