How much ammonia content is better to change the gas?
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If the purification process adopts low-temperature methanol washing process, what is the appropriate ammonia content in the shift gas? At what ammonia content should the shift gas water wash be opened and closed?
Higher than 1PPM is harmful to low-temperature methanol washing. Ammonia washing should always be turned on.
The lower the better :D :D :D
The lower the better, of course ammonia washing is required. When changing, the temperature must be controlled to avoid the generation of ammonia, and the washing water (physical water) must be reduced as much as possible.
When the ammonia content in the shift gas is high or the washing effect of the ammonia washing tower is poor, NH3 is not completely absorbed by the water. As NH3 accumulates after entering the methanol washing system, NH3 may react with CO2 or H2S to form ammonium bicarbonate or (NH4)2S crystallization, causing blockage of the filter, pressure guide pipe and other parts. (NH4)2S is generated during methanol regeneration, and (NH4)2S is circulated with methanol to the scrubber. It is decomposed into NH3 and H2S in the upper part of the scrubber, and volatilizes into the purified gas, resulting in an increase in sulfides.
It is not that the more ammonia content in methanol washing, the better~~ Ammonia in methanol washing plays a neutralizing effect~ If the ammonia content is low, it will cause serious corrosion of the equipment~ The ammonia content controlled in each place is different~ In some factories, if the ammonia content in methanol is not enough, ammonia will be added~~ The ammonia content depends on the equipment and process~ Ammonia is difficult to escape from methanol~ There is an accumulation effect, and trace amounts of ammonia will be taken out of the purified gas and acidic gas.~
The lower the ammonia content in the shift gas, the better, which can reduce ammonium salt crystallization in the heat exchanger and pipelines after the shift!
It doesn’t matter when, just keep the ammonia washing tower open. The lower the better.
Yes, the lower the better, the longer the maintenance cycle.
In low-temperature methanol washing, the lower the ammonia content, the better. A certain ammonia content needs to be considered to reduce corrosion of equipment.