Specific criteria for determining the points at which the device should be shut down
Thread Content
After shutting down the cobalt-molybdenum series conversion catalysts, pressure is maintained during shutdown; at what temperature level or after how much time must the pressure be released? Is this mainly because the formation of condensed water causes the catalyst to become prone to pulverization, or is it due to the easy formation of oxides of the cobalt-molybdenum catalyst? To what level should the pressure be released? When to purge with nitrogen? Low-temperature methanol washing unit: During short-term shutdowns of the low-temperature methanol washing unit, some plants are able to resume operation within 1 hour of the shutdown, with the methanol circulation coming to a halt. If it cannot be restored within one hour, start the short-term methanol cycle and the mixed refrigeration system; if it still cannot be restored after that, stop the methanol cycle. Is it defined by time, or by temperature or pressure parameters? How specific should it be defined? Thank you all
First, this needs to be analyzed based on the reason for the parking – whether it is a fault in the upstream or downstream equipment – and how long it will take to resolve that fault Is it still a fault within this device? How long has the fault persisted? If the time is short and it has little impact on the methanol wash cycle, the cycle can be maintained ； If the time is long, there is no need to keep the cycle running; it’s better to stop the machine for maintenance. In such situations, it is necessary to take into account both time and the actual operating status of the system; ultimately, it relies on the practical experience of the operators to ensure proper control.