Increased production of diesel oil and fuel oil

Claim 2

A PROCESS WHICH COMPRISES CRACKING A HYDROCARBON OIL IN A CRACKING ZONE; PASSING THE EFFLUENT FROM THE CRACKING ZONE TO A FRACTIONATION ZONE TO SEPARATE THE EFFLUENT INTO A PLURALITY OF STREAMS INCLUDING A GASOLINE STREAM, A LIGHT CYCLE OIL STREAM, A HEAVY CYCLE OIL STREAM AND A KETTLE PRODUCT STREAM; REMOVING A RESIDUAL OIL FROM THE KETTLE PRODUCT STREAM; THERMALLY CRACKING AHYDROCARBON FEED TO PRODUCE AN EFFLUENT STREAM CONTAINING UNSATURATED GASEOUS HYDROCARBONS; CONTACTING SAID EFFLUENT STREAM IN A QUENCH ZONE WITH A STREAM OF SAID RESIDUAL OI TO QUENCH SAID EFFLUENT STREAM; REMOVING A FIRST STREAM CONTAINING A LIGHT OIL AND CRACKED GASES AND A SECOND STREAM CONTAINING A RICH OIL FROM SAID QUENCH ZONE; SEPARATING STREAM OF LIGHT OIL FROM SAID FIRST STREAM; AND RETURNING SAID LIGHT OIL STREAM TO SAID FRACTIONATION ZONE.

Claim 3

The process of claim 1 in which the heavy cycle oil stream is passed to a stripping zone wherein light constituents are stripped from the heavy cycle oil and returned to said fractionation zone, and wherein said light oil stream is introduced Into said stripping zone, from which it enters said fractionation zone.

Claim 4

The process of claim 2 wherein said light oil stream is passed in heat exchange relationship with said light cycle oil stream prior to being introduced into said stripping zone.

Claim 5

The process of claim 2 wherein the rate of flow of said light oil into said stripping zone is maintained at a preselected rate.

Claim 6

A process which comprises cracking a hydrocarbon oil in a cracking zone; passing the effluent from the cracking zone to a fractionation zone to separate the effluent into a plurality of streams including a gasoline stream, a light cycle oil stream, a heavy cycle oil stream and a kettle product stream; removing a residual oil from the kettle product stream; thermally cracking a hydrocarbon feed to produce an effluent stream containing unsaturated gaseous hydrocarbons; contacting said effluent stream in a first quench zone with a stream of said residual oil; removing a gaseous stream containing a light oil and cracked gases from said first quench zone and passing same to a second quench zone; introducing a stream of water into said second quench zone; removing a liquid stream containing water and said light oil from said second quench zone and passing same to a separation zone; removing a stream of said light oil from said separation zone; and returning the stream of light oil removed from said separation zone to said fractionation zone.

Claim 7

A process which comprises cracking a hydrocarbon oil in a cracking zone; passing the effluent from the cracking zone to a fractionation zone to separate the effluent into a plurality of streams including a gasoline stream, a light cycle oil stream, a heavy cycle oil stream and a kettle product stream; removing a residual oil from the kettle product stream; thermally cracking a hydrocarbon feed to produce an effluent stream containing unsaturated gaseous hydrocarbons; contacting said effluent stream in a first quench zone with a stream of said residual oil; removing a gaseous stream containing a light oil and cracked gases from said first quench zone and passing same to a second quench zone; introducing a stream of water into said second quench zone; removing a liquid stream containing water and said light oil from said second quench zone and passing same to a separation zone; removing a stream of said light oil from said separation zone; and returning the stream of light oil removed from said separation zone to said fractionation zone.

Claim 8

The process of claim 5 wherein the rate of flow of said light oil into said fractionation zone is regulated in response to a measurement of the interface level in said separation zone so as to maintain a preselected interface level in said separation zone.