Fluid coking with preparation of seed coke

Claim 1

IN A PROCESS FOR COKING A HEAVY HYDROCARBON OIL WHICH COMPRISES THE STEPS OF CONTACTING A HEAVY OIL COKING CHARGE STOCK AT A COKING TEMPERATURE WITH A BODY OF COKE PARTICLES MAINTAINED IN THE FORM OF A DENSE TURBULENT FLUIDIZED BED IN A REACTION ZONE; REMOVING PRODUCT VAPORS FROM THE REACTION ZONE; CIRCULATING THE COKE THROUGH AN EXTRANEOUS HEATING ZONE, WHEREIN A PORTION OF THE COKE PARTICLES ARE BURNED, AND SENT BACK TO THE REACTION ZONE TO SUPPLY HEAT THERETO; THE IMPROVEMENT WHICH COMPRISES ATOMIZING A HEAVY HYDROCARBON OIL HAVING A HIGHER CONRADSON CARBON RESIDUE THAN THE CHARGE STOCK AND IN AN AMOUNT OF FROM 7 TO 15 VOLUME PERCENT BASED ON THE CHARGE STOCK INTO A DRYING ZONE TO PRODUCE SMALL OIL DROPLETS HAVING A DIAMETER IN THE RANGE OF 150 TO 600 MICRONS; COUNTERCURRENTLY CONTACTING THE ATOMIZED OIL DROPLETS WITH HOT FLUE GAS FROM THE EXTRANEOUS HEATING ZONE AT A TEMPERATURE IN THE RANGE OF 1000* TO 2500* F. AND HAVING A VELOCITY OF 1 TO 4 FT./SEC. WHEREBY COKE SEED PARTICLES HAVING A DIAMETER SIZE DISTRIBUTION OF PREDOMINANTLY 75 TO 150 MICRONS ARE FORMED; WITHDRAWING THE COKE SEED PARTICLES FROM THE DRYING ZONE AND SENDING THE COKE SEED PARTICLES TO THE REACTION ZONE.