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In a small topping plant we are experiencing a high quantity of organic chloride in Naphtha: about 5-10 ppm whereas requirement is less than 1 ppm. We don't know where this is coming form. Crude has less than 2 ppm (the astm method to determine organic chloride in fact distill off naphtha to check organic chloride). Is there a treatment method? Heard that activated charcoal can be used. The other issue is the inlet line to tank has 1.8 ppm but the tank has 5 ppm.
 
Answers
30/10/2015 A: Hubert Mueller, Bayernoil, guhumueller@web.de
Many years ago we realized a lot of organic chlorides entering our refineries via the crude pipelines. The sources at this time were contaminated gasoil batches also transported via the crude pipeline system. Some shippers cleaned their vessels with organic chlorides and sent this liquid together with the relevant batches to the refineries.
To check for organic chlorides in the lab, we topped off the naphtha cut and analysed this for the stuff, the advantage: you get the chlorides concentrated in this cut.
Serious corrosion problems were the result in our Naphtha Hydrotreaters because of the high concentration of HCl in the reactor effluent and a pH of 1 in the water boot of the separators. The only thing we could do at that time was to run a continous water wash with ammonia in the wash water in order to neutralize the acid and to control the pH close to 7 in the waterboot.
Essential is to find out the sources of the organic chlorides and to eliminate them.
By th way: Did you check your slops reprozessing?