Why is the air vent opened during the heating-up phase of starting up the ammonia synthesis tower?
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Our facility uses the hydroformylation process to produce ammonia, with methanol as a by-product. During the startup and heating phase of the ammonia synthesis tower, it is necessary to allow air to flow in; is it possible to avoid this? Please advise
This depends on the duration of the shutdown of the ammonia synthesis tower, as well as whether there are safety gases available to protect the catalyst inside the tower. If the gas is protected by nitrogen, during the heating process, it is necessary to vent some of it slightly; once the nitrogen concentration is adjusted to the proper level, the pressure is maintained at the required value as heating proceeds. If there is hydrogen and nitrogen at a certain pressure inside the tower, with a target value of 5.0 Mpa, pressure needs to be added if it is below this value, and pressure needs to be released if it is above this value. If driving after replacing the catalyst or if the tower has been shut down for a long time, then from a safety perspective, venting is also necessary during the heating process.
The explanation for going upstairs is very detailed. The purposes of leaving it empty are, first, to control pressure, second, for displacement, and third, to adjust the gas composition.
Detailed on the 2nd floor, concise on the 3rd floor: handshake
It is mainly related to safety; if the pressure can be well controlled, it’s not necessary to turn it on, and a nitrogen circulation method can also be used