Ammonia scrubber put into operation
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When starting up the ammonia washing tower, should oil or gas be fed in first?
I have no experience with this type of tower; I think in ordinary scrubbers, a liquid circulation system is established first, and then the process gas is introduced! Please continue the discussion!
I don’t understand; ammonia scrubbers are washed with water or phosphoric acid, so why is there also oil washing? When starting up a tower such as an ammonia scrubber, a liquid circulation system should be established first, before introducing gas. The prerequisite is that the system be replaced before driving.
Without introducing air, neither the liquid level nor the washing liquid circulation is established~! The liquid level is established only after the process gas is introduced~! The initial washing volume is very small! As long as the liquid level can be kept stable, that’s fine~! When it’s time to direct the gas to the lower methane section, the volume of washing water isn’t that large either! This is because establishing the ammonia content in methanol first can lead to severe corrosion of the equipment during the initial operation phase; after introducing lower-pressure methane gas, the amount of washing solution is gradually increased
In ammonia washing towers, the liquid level circulation is first ensured to be operating properly before process gas is introduced! Why is it only put into use after gas purification in low-temperature methanol washing? It seems that not many companies do this!
The gas volume should be sufficient to support the operation of the tower; the ammonia scrubber should be put into use only after the pressure meets the required levels. If it is activated after gas is introduced into the low-temperature methanol scrubber, ammonia will be carried into that system
When starting up the ammonia scrubbing tower for coke oven gas, it is necessary to first purge it with steam (although nitrogen purge is preferable). After that, coal gas should be introduced quickly, followed by establishing a circulation of the scrubbing liquid. Otherwise, completing the displacement with steam and immediately establishing a washing liquid circulation will cause severe negative pressure inside the tower! ! There is a risk of tower instability. This problem does not exist with nitrogen purging.
Perhaps the question posed by the original poster is the kind answered on floor 7 – the ammonia scrubbing towers used in low-temperature methanol washing employ deoxygenated water for cleaning.
In the denitration tower of the purification process, some are located in the shift unit (the last device). At the beginning of operation of this process, when no gas is sent to the methanol scrubber, it is not necessary to use flushing water at that time, as the process gas is simply vented. In practice, however, in order to prevent ammonia from crystallizing in the process gas, flushing water is used before sending the gas through the system； Some ammonia removal towers are located in the methanol washing unit, and there is an ammonia cooler in front of such towers; therefore, the washing water for the ammonia removal tower must be put into use before introducing the gas, in order to prevent ammonia in the process gas from crystallizing at low temperatures.
For any startup, a liquid circulation system must first be established; gas is introduced only after the system has been verified to be suitable