What to do if the sulfuric acid plant has a persistent high temperature?

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In recent years, it has been common to observe that some contact process sulfuric acid plants suffer from persistent high temperatures, manifested primarily by the inlet temperatures of the beds following the conversion stage exceeding normal levels significantly; for example, the inlet temperature of the second conversion bed reaches 490 degrees Celsius, while that of the third conversion bed reaches 500 degrees Celsius. The reason for the \"high temperature\" in the sulfuric acid conversion unit is often a perforation in one of the conversion layers, or a rapid decline in the activity of the catalyst in that layer due to its poor thermal stability, which in turn causes the conversion reaction to shift backward. In the case of the aforementioned shift in the reaction temperature, the inlet temperature of the subsequent bed layer exceeds the designed value by a large margin, causing the vanadium catalyst to develop a temperature memory. When the user resolves the problems in the first conversion stage through maintenance, they will find that the catalyst activity in the subsequent bed layers decreases, and the overall conversion rate also drops significantly. This is the memory effect resulting from the catalyst having operated at high inlet temperatures for an extended period of time. To avoid temperature memory formation in the catalyst of subsequent beds under the aforementioned conditions, once a delay in the conversion reaction is detected, especially when the inlet temperature of the subsequent beds exceeds normal levels significantly, the plant should be shut down as soon as possible. If the vehicle is not stopped and dealt with in time, the only solution in the end will be to replace a large amount of catalyst.