Abstract: An apparatus for reducing the coke dust in the decoking effluents of the hydrocarbon cracking ovens according to the invention provides means for the condensation of the effluent, means for collecting a liquid condensate, means for filtering said liquid condensate, and means for washing the residual vapours and gases that cannot be condensed by using the same condensate suitably filtered from coke, the filtered condensate being evaporated for the following discharge to the atmosphere by using the thermal content of the input decoking gases. A process for reducing the coke dust in the decoking effluents of the hydrocarbon cracking ovens according to the invention consists in that the solid content in the gaseous effluent from the decoking is removed by filtration of the condensate from said gaseous effluent and by washing of gases and vapours contained therein that cannot be condensed.

Abstract: A method and an apparatus for the largest recovery of ethylene and propylene from gas produced by the pyrolysis of hydrocarbons, wherein any liquid current produced by the fractional condensation of the raw gas up to a definite temperature is directly fed to an ethane fractionating column (deethanizer) the bottom product of which is the purified current containing almost all propylene, while any current condensed at lower temperature is fed to a methane separating column (demethanator) provided with a reboiler in which the partial condensation of the overhead vapor of the deethanizer occurs, and the bottom product of the demethanator contains all ethylene.