Short-time contacting of fluids with solids in hydrocarbon conversion

Claim 1

THE PROCESS OF CRACKING HEAVY HYDROCARBONACEOUS RESIDUES WHICH COMPRISES MIXING SAID RESIDUES WITH HOT SUBDIVIDED COARSE COKE SOLIDS HAVING A PARTICLE SIZE OF 35 TO 325 MESH TO FORM A MIXTURE HAVING CRACKING TEMPERATURE, PASSING SAID MIXTURE AT A VELOCITY OF ABOUT 5 TO 40 FEET PER SECOND AT SAID CRACKING TEMPERATURE UPWARDLY THROUGH A NARROWLY CONFINED EXTENDED PATH FOR A TIME OF ABOUT 1 SECOND, SUFFICIENT TO CAUSE SUBSTANTIAL CRACKING OF SAID RESIDUE, OBSTRUCTING THE FLOW OF SAID MIXTURE ON SAID PATH IN A PLURALITY OF SECTIONS BY FLOW OBSTRUCTIONS DEFINING A TORTUOUS COURSE FOR SAID MIXTURE, SAID STAGES BEING SEPARATED BY UNOBSTRUCTED SECTIONS MAINTAINING THE FLOW VELOCITY OF SAID MIXTURE ON SAID PATH SUFFICIENTLY HIGH TO CAUSE SUBSTANTIAL SEPARATION OF SOLIDS FROM GASIFORM CRACKING PRODUCTS WITHIN SAID STAGES AS THE RESULT OF RAPID CHANGES IN THE DIRECTION OF FLOW OF SAID MIXTURE THROUGH SAID PATH, CONCENTRATING SOLIDS SO SEPARATED IN PERIPHERAL SECTIONS OF SAID PATH, PASSING A RELATIVELY DILUTE SUSPENSION OF SOLIDS IN GASIFORM CRACKING PRODUCTS THROUGH THE CENTRAL PORTION OF SAID PATH, WITHDRAWING A PORTION OF SAID SUSPENSION FROM A CENTRAL PORTION OF AT LEAST ONE OF SAID UNOBSTRUCTED SPACES, AND WITHDRAWING THE REMAINDER OF SAID SUSPENSION FROM THE TOP OF SAID PATH, THE AVERAGE RESIDENCE TIME ON SAID PATH OF SAID CONCENTRATED SOLIDS BEING 5 TO 10 TIMES THAT OF SAID DILUTE SUSPENSION WHICH LEAVES SAID PATH AT A VELOCITY OF ABOUT 40 TO 100 FEET PER SECOND.