Two-stage fluid coking

Claim 2

A process according to claim 2 wherein said cracking temperature in said second reaction zone is between about 20* and about 50* F. higher than in said first reaction zone.

Claim 3

A process according to claim 1 wherein a portion of said heavy hydrocarbon material is atomized before contacting with said hot particulate solids.

Claim 4

A process according to claim 4 wherein said heavy hydrocarbon material is atomized by contacting with a stream of steam or recycled light gaseous products which have been recovered from said second reaction zone.

Claim 5

A process according to claim 5 wherein said atomizing and contacting occur simultaneously in said first reaction zone.

Claim 6

A process according to claim 6 wherein said oil is atomized by contacting with a stream of steam or recycled light gaseous products which have been recovered from said second reaction zone.

Claim 7

A process for cracking a heavy residual oil having a Conradson carbon number generally between 20 and 50 to form coke and lighter gaseous and liquid hydrocarbon products, which comprises: contacting said oil with hot particulate solids in a first reaction zone operating at a cracking temperature between about 900* and about 1,000* F. and at a cracking temperature between about 15 and about 50 psig to produce said lighter products, said contacting being for a period of time between about 0.5 and about 10 seconds; passing said remaining oil, said hot particulate solids, said lighter products and coke into a second reaction zone operating under cracking conditions more severe than in said first reaction zone to enable more of said oil to be cracked to more lighter products; and recovering said lighter products from said second reaction zone.

Claim 8

A process according to claim 8 wherein a portion of said oil is atomized before contacting with said hot particulate solids in said first reaction zone.

Claim 9

A process according to claim 8 wherein a portion of said oil is atomized simultaneously with said contacting in said first reaction zone.

Claim 10

A process according to claim 8 wherein said contacting in said first reaction zone which is a transfer line reactor being for a period of time between about 1 and about 2 seconds.

Claim 11

A process according to claim 11 wherein said second reaction zone is a transfer line reactor, and said oil is contacted with said hot particulate particles for a period of time between about 1 and about 5 seconds.

Claim 12

A process according to claim 8 wherein said cracking conditions in said second reaction zone is more severe than in said first reaction zone in that said cracking temperature in said second reaction zone is higher than in said first reaction zone.

Claim 13

A process according to claim 13 wherein said cracking temperature in said second reaction zone is between about 20* and about 50* F. higher than in said first reaction zone.