Acidic water from the top of the distillation tower
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What are the important substances in the acidic water at the top of the distillation tower? What is the function and principle of washing with water?
Acidic substances in the vapor at the top of the distillation tower, such as H2S, RSH, HCI, HCN, etc. These acidic substances are primarily generated during the catalytic cracking process from sulfur, nitrides, and salts present in the feedstock. Liquid ammonia mixed with water is used for washing to produce ammonia water; the ammonium salts resulting from the neutralization reaction dissolve in water and can be separated from the vapor stream as sulfur-containing wastewater in the overhead gas oil separator of the distillation tower. At this point, the ammonium ions in ammonia are in an ionic state, giving it a weakly alkaline nature. It can react with the acidic substances (hydrogen ions) in oils to produce salts and water. It serves to neutralize the oil