Halides removal washing system for a hydrocarbon stream
A halides removal washing system for absorbing halides from a process gas within a process gas duct comprising a wash water injection nozzle and anti-precipitation means arranged around the nozzle, injection pipe and within the process gas duct.
1 . A halides removal washing system comprising:
a process gas duct for process gas comprising hydrocarbons and halides;
an injector pipe extending into the process gas duct, said injector pipe having a wash water inlet in a first end of the injector pipe arranged outside the process gas duct and a wash water outlet with an injector nozzle in a second end of the injector pipe adapted to spray the wash water into the process gas in the process gas duct downstream of the injector nozzle, wherein mixing of the wash water and the process gas results in washout of hydrochloric acid (HCl) at a level above 99.9%; and
anti-precipitation means comprising electrical heating wiring arranged around at least a part of the injector pipe which extends into the process gas duct, and an injector purge channel arranged around the injector nozzle and adapted to provide a relatively hot injector purge fluid as compared to the temperature of the wash water,
wherein the process gas duct has an anti-corrosion liner arranged on the inside surface of the process gas duct downstream of the injector nozzle, wherein the anti-corrosion liner is arranged with a gap between the inside surface of the process gas duct and the anti-corrosion liner allows for a duct purge fluid between the anti-corrosion liner and the process gas duct, and further comprising: (1) a sealing provided between the anti-corrosion liner and the process gas duct such that the process gas does not enter the gap, and (2) a purge fluid connection to the process gas duct downstream of the injector nozzle adapted to purge fluid into the gap between the anti-corrosion liner and the process gas duct; and
wherein the halides removal washing system prevents precipitation of ammonium chloride (NH 4 Cl).
2 . The halides removal washing system of claim 1 , wherein gap is from 0.2-50 mm between the inside surface of the process gas duct and the anti-corrosion liner.
3 . The halides removal washing system of claim 1 , further comprising a duct purge fluid consumption monitoring system adapted to provide an alarm output if the duct purge fluid consumption exceeds a pre-set value.
4 . The halides removal washing system of claim 1 , further comprising at least one fluid mixer element arranged within the process gas duct downstream the injector nozzle.
5 . The halides removal washing system of claim 1 , further comprising a plurality of injector pipes and a plurality of injector nozzles.
6 . The halides removal washing system of claim 5 , further comprising:
a common process gas duct upstream the injector nozzles; and
a plurality of process gas ducts downstream each of the injector nozzles.