Abstract: A process for treatment of aluminum chloride production offgas containing Cl.sub.2, CO, CO.sub.2, HCl, COCl.sub.2, COS, SO.sub.2, N.sub.2, SiCl.sub.4 and metal chlorides by reaction with water vapor in the presence of an alumina or low iron sand catalyst to convert SiCl.sub.4 and metal chlorides to the corresponding oxides and HCl; subsequent reaction of COCl.sub.2 with water vapor in the presence of an activated carbon catalyst to form CO.sub.2 and HCl; and removal of HCl by contacting the offgas with liquid water. Reaction with steam in the presence of alumina catalyst prior to reaction with steam in the presence of an activated carbon catalyst prolongs the useful life of the activated carbon catalyst and avoids the necessity of removing SiCl.sub.4 and metal chlorides from the offgas by adsorption onto dry activated carbon prior to contacting the activated carbon catalyst with offgas.

Abstract: The method of burning fume, including combustible gases and gas-borne particles, comprising moving the fume in a tube having a blind end and one or more slits in the tube short of the end, while the fume is at least partially at ignition temperature, and emitting the fume into the air, the slit width and the slit total area being chosen such that the fume velocity through the slits will be more than the flame velocity and up to the flame blow-out velocity. The device includes a tube having a closed end and slits having a width between one-eighth and 1 inch and preferably about five-eighths inch, and a length of between one-eighth and one-half of the circumference.