Oil cracking and hydrotreating process

Claim 1

THE PROCESS OF REFINING A SULFUR-CONTAINING HEAVY OIL HAVING AT LEAST 10% BY VOLUME OF HYDROCARBONS BOILING ABOVE 900*F., WHICH COMPRISES PASSING AT ELEVATED PRESSURE SAID HEAVY OIL IN THE LIQUID PHASE AND HYDROGEN THROUGH A CRACKING ZONE TO CONVERT AT LEAST 25% BY VOLUME OF SAID HYDROCARBONS BOILING ABOVE 900*F. TO HYDROCARBONS BOILING BELOW 900*F., AND CONTACTING AT ELEVATED PRESSURE THE THUS CRACKED OIL IN THE LIQUID PHASE AND HYDROGEN WITH A PARTICULATE SULF-ACTIVE HYDROGENATION CATALYST IN A HYDROTREATING ZONE, WHILE RECYCLING REFINED LIQUID OIL FROM SAID HYDROTREATING ZONE TO SAID CRACKING ZONE AT A RATE OF AT LEAST 0.5 VOLUMES OF SAID REFINED OIL FOR EACH VOLUME OF SAID HEAVY OIL ENTERING SAID CRACKING ZONE, THE LIQUID FLOW RATE OF THE THUS CRACKED OIL THROUGH THE HYDROTREATING ZONE BEING SUFFICIENT TO MAINTAIN SAID PARTICULATE HYDROGENATION CATALYST IN RANDOM MOTION.