Catalytic cracking of petroleum hydrocarbons comprises use of double tube reactor, producing reaction streams for separation into lighter products

摘要

The cracking process takes place in four stages commencing with the introduction of catalyst and charge in the inner tube and the concentric space between the inner and outer walls of the reactor, and terminating with the separation of the catalyst for regeneration and the separation of the hydrocarbon products obtained. The process comprises: (i) supplying catalyst to an inner reactor tube and the concentric space between the inner and outer tubes in ascending mode by the action of a pre-lifting medium; (ii) supplying a hydrocarbon charge to the inner and outer spaces to contact with the catalyst to form an oil/catalyst mixture, so that a reaction occurs in cracking conditions to form an ascending reaction stream; (iii) propagating the reaction streams from the inner tube and the concentric space together to the entry of the confluence tube and to a separation unit where the hydrocarbon products are separated from the catalyst; and (iv) separating the hydrocarbons into different products including petrol, diesel oil and liquefied petroleum gas, re-generation of used catalyst and recycling of the latter.