What are the reasons for high chloride ions in the acidic water at the top of the catalytic cracking fractionator, and what are the solutions?
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What are the reasons for high chloride ions in the acidic water at the top of the catalytic cracking fractionator, and what are the solutions? The chloride ion content in the acidic water from our equipment is sometimes very high, while at other times it is below 30. What is the reason for this? How to solve it?
It’s probably a problem with the raw materials; improve the operation of electrodesalination.
The main source is the feed to the unit (including atmospheric wax oil, coker wax oil, vacuum residue, etc.), and the primary solution is to improve the electrodialysis operations in the atmospheric unit, particularly by controlling the amount of water injected into the electrodialysis process.
The term \"raw materials brought in from the atmospheric and vacuum distillation units\" doesn’t quite make sense. As I understand it, due to the temperature in the tower, the Cl ions in the atmospheric and vacuum distillation process are generally found in the upper part of the tower, while the catalytic feedstock is located in the lower part and contains little Cl ions. Delayed coking is not very clear, but it should be similar. I suspect it might be the Cl ions contained in your additives, or it could be a problem with the testing method.
It must be brought in by the crude oil; presumably the chlorine content in the gasoline from the atmospheric distillation column is also quite high
You should provide the composition of your catalytic feed so that it can be determined. Are any additives being used as well?
I also agree with the possibility that chlorine from the raw materials is the cause. Because some local refineries do not use electrical desalination at all; the purchased fuel oil is fed directly into the catalytic units, which causes chlorine to end up in the acidic water.