Ammonia extraction via side line from a single tower? ?
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I would like to ask about the procedures for ammonia extraction via the side line of a single tower. Should this ammonia extraction be carried out continuously, or should one wait until a certain amount of ammonia has accumulated? Please provide details on the specific operating parameters. The normal tower pressure is around 0.4–0.42 Mpa, and the temperature at the top of the tower can initially be kept between 30 and 40 degrees Celsius; however, it’s easy for this temperature to rise to between 120 and 140 degrees Celsius. How can this be controlled? There is also the temperature at the bottom of the tower; when ammonia is extracted, it should be kept between 17 and 21, while it should range from 135 to 140. However, the temperature at the bottom of the tower can only reach 140–145. How can this be increased? What should be the temperature control for the ammonia extraction heat exchanger? In front of the liquid-sealing tube on the primary side line; I hope everyone can provide more suggestions
Ammonia extraction is ongoing! The temperature for ammonia extraction between 17 and 22 should be maintained between 140 and 150 degrees; the top temperature can be controlled at around 30 degrees using cold feed, the bottom temperature of the tower should be 160 degrees, and the temperature of the heat exchanger used for ammonia extraction should be around 120 degrees!
It’s not easy to control the temperature at the top of the tower; it quickly rises above 100 degrees. Is it impossible to keep it under control? Is there any good solution?
What is the ratio of hot feed to cold feed?
The ratio of cold to hot is generally around 1:4 to 1:7, with adjustments made according to concentration and processing load. There are generally three possible reasons for the total impulse at the tower top: first, too much acidic gas is drawn out from the tower top; second, the amount of ammonia in the gas drawn off via the side stream is too low, or the ammonia content in the acidic water fed into the tower is too high; third, the flow rate of the cold material is too low or its temperature is too high
What was said upstairs is completely correct – is there something wrong with your tower trays? Otherwise, it’s impossible for the temperature to be that low; the bottom of the tower remains at 160°
We have encountered such a situation before: the opening at the top of the tower remained unchanged, but the temperature at the top rose rapidly, to around 120. A higher temperature means more liquid present. We had to shut down the furnace at that time; now the ratio of cold to hot feed is approximately 1:2, and the temperature at the top of the tower remains around 60. As for the other parameters, as well as the steam conditions, there aren’t any significant changes
I think all of your parameters are a bit abnormal; especially the temperature of the side stream, which is too low. This can lead to blockages in the side stream, and it also causes the ammonia distribution within the tower to shift downward； Another issue is that your tower pressure is controlled at too low a level; as a result, acidic gases are easily drawn in in large quantities. Once water vapor reaches the top of the tower, the temperature there will definitely rise above the desired level. With such low tower pressure, it becomes difficult to raise the tower temperature. A low temperature at the bottom of the tower makes it hard to ensure the quality of the purified water, because generally, regardless of the tower pressure, the temperature at the bottom remains around 160 degrees. Temperature has a greater impact on stripping than pressure, so it is the primary parameter for stripping processes.