Hydrogen donor diluent cracking process

• US 4,090,947 A
• Filed: 08/08/1977
• Issued: 05/23/1978
• Est. Priority Date: 06/04/1976
• Status: Expired due to Term

• Current Assignee: Continental Oil Company
• Original Assignee: Continental Oil Company
• Inventors: Satchell, Donald P. Jr.
• Primary Examiner(s): Levine, Herbert
• Application Number:
  US05/822,573
• Time in Patent Office: 288 Days
• Field of Search: 208/50, 208/53, 208/56
• US Class Current: 208/56
• CPC Class Codes: C10G 47/34 Organic compounds, e.g. hydrogenated hydrocarbons

Abstract

A hydrogen donor diluent cracking process for converting hydrogen deficient residual petroleum oils to more valuable distillates. A premium coker gas-oil is utilized as the hydrogen donor diluent.

Claims

1. In a thermal cracking process for converting heavy petroleum residual oil to lighter distillate products in which the thermal cracking of the residual oil takes place in the presence of a hydrogen donor diluent, the improvement wherein the hydrogen donor diluent comprises hydrotreated heavy premium coker gas-oil produced in a premium coking operation utilizing a coke drum pressure of from 10 to 150 psig, a coker furnace transfer line temperature of from 900°

to 960°

F and a coke drum overhead vapor temperature of from 825°

to 900°

F and operated at conditions such that the coke produced has a coefficient of thermal expansion of about 5 times 10^-7 /°

C or less.

2. The process of claim 1 wherein the products of the thermal cracking process are fractionated, the gas-oil fraction is passed through a hydrotreater in which said fraction is hydrotreated, and the hydrotreated fraction is recycled as hydrogen donor diluent in said thermal cracking process.

3. The process of claim 1 wherein the products of the thermal cracking process are fractionated, the gas-oil fraction passed to a premium coker unit, heavy premium coker gas-oil from said coker unit is passed to a hydrotreater for hydrogenation thereof, and the hydrogenated premium coker gas-oil is utilized as hydrogen donor diluent in said thermal cracking process.

4. The process of claim 1 wherein the products of the thermal cracking process are fractionated, a side stream from said fractionation is passed to a premium coker unit, vapors from said premium coker are returned to said fractionator, and a gas-oil fraction from said fractionator is passed to a hydrotreater for hydrogenation and subsequent reuse as hydrogen donor diluent in said process.

5. The process of claim 1 wherein said hydrogen donor diluent is a heavy premium coker gas-oil having a boiling range of from 650°

to 900°

F.

6. The process of claim 1 wherein said hydrogen donor diluent consists essentially of a mixture of:

(a) premium coker gas-oil taken directly from a premium coker unit; and

(b) a recycled fraction boiling in the gas-oil range and obtained by fractionation of the products from said thermal cracking process.

7. The process of claim 1 wherein about one volume of diluent is added to each volume of residual oil fed to said thermal cracking process.

8. The process of claim 1 wherein the heavy premium coker gas-oil is produced in a premium coking operation utilizing a coke drum pressure of from 30 to 70 psig, a transfer line temperature of from 920°

945°

F and a coke drum overhead vapor temperature of from 840°

to 880°

F.