HCl / Chlorine Scrubbing
Chlorine gas (Cl2) or hydrogen chloride (HCl) is scrubbed using an ejector venturi gas scrubber or counter current packed tower. A venturi gas scrubber is an “eductor”-type design. It makes use of the scrubbing liquid as the motive fluid to pull the gas stream into and through it without the need of another device, such as a fan, to move the gas. The liquid and gas streams thoroughly mix, and the HCl transfers from the gas phase to the scrubbing liquid phase.
A single-stage ejector venturi gas scrubber can typically achieve 95 percent contaminant removal. A countercurrent packed tower is used to achieve even highercontaminant removal efficiencies, up to and exceeding 99.9 percent. This device is a vertical tower in which the scrubbing liquid flows downward countercurrent to the upward gas flow over a bed of packing pieces that function primarily to provide a surface area on which the two streams come into contact.