GB583176A - Improvements in or relating to the separation of suspended particles from vapors or gases - Google Patents

Abstract

<PICT:0583176/III/1> In processes using a fluidised catalyst, such as in the cracking of oils, the regenerated catalyst is recovered from the effluent gases by an electrostatic separation process, in which ammonia is added to the gases to aid the separation. The plant to which the invention is applied is shown in the drawing. The oil vapours and a fluidised catalyst, consisting principally of silica and alumina enters the cracking chamber 1 by way of the pipe 2 and heater 12. At the top and outlet of this chamber centrifugal separators 3, 5 remove most of the solids from the gas stream, which is passed to a condenser 7 and separation drum 8 from which the permanent gas is taken off by a pipe 9 and the distillate by a pipe 10. The fluidised solid is withdrawn from the bottom of the chamber 1 by a pipe 11, and a portion which contains a rather large portion of spent catalyst coated with carbon is fed by way of a cooling coil 16 to a regenerator 15, to which air or other regenerating gas is delivered by a pipe 20. Most of the regenerated catalyst is separated by centrifugal separators 21, 22 and returned to the cracking chamber by way of the pipe 18. The effluent gas carrying the residue of catalyst is delivered to an electrostatic separator 23, and the deposit delivered separately or to the main stream. Ammonia is fed in small quantities to the separator by a pipe 24 or introduced in any other convenient manner.