Discharge from the ammonia purification tower
Thread Content
I have an ammonia purification tower on the wastewater stripping side line for ammonia extraction; by periodically feeding liquid ammonia into this tower, the H2S in the ammonia gas is removed. May I ask that the ammonium salts from dissolved ammonia water need to be removed from the purification tower regularly? Let’s discuss what impact it has on ammonia purification if it isn’t discharged for a long time Plus points, welcome to discuss
If ammonium hydrosulfide is not removed over an extended period of time, the higher the concentration of ammonium hydrosulfide, the higher the partial pressure of hydrogen sulfide in the gas phase. This prevents hydrogen sulfide from escaping from the gas phase, and it may even lead to the decomposition of ammonium hydrosulfide, resulting in an increase in hydrogen sulfide levels in the ammonia gas. Although the partial pressure of ammonia in the gas phase is high, hydrogen sulfide is already present in trace amounts in crude ammonia gas; therefore, this process still occurs. From a reaction kinetics perspective, hydrogen sulfide reacts with ammonia; the more ammonium hydrosulfide there is, the lower the extent of the reaction in the forward direction. My personal understanding is for reference only
The main function of the ammonia purification tower is to reduce temperature; it is the desulfurizer that is used primarily for desulfurization. As long as the temperature at the top of the tower remains low, no additional measures are taken. Only when the temperature at the top of the tower rises and the liquid level increases is it necessary to remove liquid from the system. Generally, there is no need to do this, and ammonium hydrosulfide crystals will not form even after the system has been in operation for a month or two!