Some oil products(kerosene, diesel) can containt naphtenic asids. in order to remove them caustic soultion is used and as outcome of this some units generate caustic wastes. Caustic soda is used also for Kerosene demerkaptanization.
Most of the acids are formed on the front end of the process where you have a desalter. You form hydrated salts which ultimately make acids when you add heat. Caustic is added to the desalter to maintain pH. Caustic is also used on downstream condensers as a water wash to neutralize acids and prevent condenser failure. Some alky units use caustic to remove HF from their propane. Caustic scrubbers can be used in various plants.
thanks it was helpful, well i need to find a away to treat caustic waste that went through an oil refinery process. turns out it has high BOD, COD, sulfide and mecaptan...i need to prevent the formation of hydrogen sulfide in the waste.
Zimpro sounds like exactly the kind of tech i needed thanks. Anyways, we're trying an alternative we're going to use microbes to immobilize the sulfur in the waste stream. hopefully this would lower the BOD and COD significantly. thanks for all the help