Double riser FCC reactor process using a light and mixed light / heavy feed

摘要

The first and second hydrocarbon feed (5 and 6), each one the first and second riser (2 and being supplied 4) to, ethylene and propylene and/or the effluent which is rich in aromatic is formed, double riser FCC process is disclosed. When the hydrocarbon feed differs, ethylene and/or to possess the condition in order to make the transformation to propylene profitable for differing it is possible the respective riser. The little coke precusor (80 and 82) the hydrocarbon feed (5 and 6) one or adding to both, although it maintains system at heat balance, to decrease or to abbreviate the quantity of the makeup fuel which is needed it is possible. The coke precusor and optional recycling style (36 and 44) it separates the various feed which are included, into classification, can improve olefin yield, the paraffin feed to the riser of one side, the execution form which to the other riser is supplied is included the olefin feed.