Synthetic Ammonia Process Technology Exchange Area [Daily Question 2009-02-19]
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Synthetic Ammonia Process Technology Exchange Area [Daily Question 2009-02-19] How do you carry out short-term shutdown control and purging at the medium-low-low shift positions {using steam}? Requirements: Insulate and retain moisture, but not maintain pressure. Last edited by jindin312 on 2009-2-19 17:11]
Personally, I think it’s not appropriate to temporarily stop using steam for position switching. Because after replacing with steam, maintaining pressure in the medium and low-temperature converters becomes a problem; if the pressure cannot be maintained, air may enter the converters, causing the catalyst to oxidize and leading to overheating or other hazards. At the same time, replacing with steam may also lead to the pulverization of the catalyst.
I think using steam is not appropriate, as steam displacement brings the following disadvantages: 1. Steam can cause the medium-temperature catalyst to become pulverized. 2. Steam displacement can lead to an excessively high steam-to-gas ratio in the low-temperature reformer, resulting in desulfidation of the catalyst in that unit. 3. After replacing with steam, there is a problem with pressure retention in the system (the system becomes under pressure when the temperature drops). Safety is still a problem.