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Insights on Distillation Operations The ammonia distillation process is a key point in reducing material consumption and energy consumption in the entire factory. (1) Strictly control the pressure at the bottom, middle and outlet of the tower within the specified range, and keep it stable without sudden rise or fall. (2) The amount of steamed mother liquor and the amount of ash added should be as stable as possible with small fluctuations. The liquid level in the mother liquor barrel should be balanced and the distillation tower should be kept at 90% of its maximum production capacity. This can improve the heat and mass transfer effect of the packed tower. Reduce steam consumption. (3) Control the gas outlet temperature at the top of the tower between 85-88°C. Usually, the steam volume and the steam entering the tower are generally adjusted. The opening of the dilute liquid reflux valve can also be adjusted (after the amount of dilute liquid pump is stable) (4) According to the changes in the concentration and temperature of each material (whether the lime is over-burned, causing changes in activity, as well as the composition of the mother liquor, the concentration and temperature of the ash milk, and whether the steam flow at the bottom of the tower escapes out of the tower with the waste liquid), analyze the size of the excess ash with reference to the liquid level, carefully adjust the amount of mother liquor and gray milk added in a timely manner, increase or decrease the amount of steam in a small amount, increase the temperature of the mother liquor appropriately, and control the CO2 of the preheated mother liquor at an appropriate value. (5) In view of the multiple occurrences of mercury backdraft during the opening and closing of the tower during production, in order to avoid this phenomenon, let's start with the tower. Usually, after opening up the entire process, increase the steam flow and maintain the medium temperature at the high limit (around 105°C). In addition, before feeding, drain the water in the pre-ash bucket for 5-10 minutes, then add the gray milk for 5-10 minutes, and then slowly add the mother liquor. The amount of mother liquid entering the tower must be controlled and not too fast to prevent a vacuum from forming in the tower. When the tower is stopped for replacement, the amount of seawater added to the pre-ash bucket should not be too large. This is because the tower temperature is very high, above 100°C, the pre-ash bucket is high, and the seawater temperature is low. If water is added too quickly, it is easy to cause mercury to be sucked back into the pre-ash bucket. (6) In case of unexpected emergencies during operation (such as sudden power outage, ash outage, sudden drop in steam or sudden increase in compressed exhausted steam). ) Don’t rush around, keep a clear mind, treat them calmly, and solve them one by one.