Efficient method for improved coker gas oil quality

1. A delayed coking process comprising the following steps:

a. introducing coke drum vapors into a flash zone of a fractioning column of a delayed coking unit, wherein the delayed coking unit includes a coker furnace, at least two coke drums, a coke transfer line extending from the coker furnace to the coke drums, a fractionating column having multiple separation trays, a coke drum vapor line extending from the coke drums to the fractionating column, wherein the fractionating column having multiple separation trays is a cylindrical shaped vessel, wherein the fractionating column is defined by sidewalls, a bottom end, and an upper end, wherein the fractionating column includes a light coker gas oil draw, a heavy coker gas oil draw located below the light coker gas oil draw, a heavy heavy coker gas oil draw located below the heavy coker gas oil draw, a flash zone located below the heavy heavy coker gas oil draw, a coke drum vapor inlet located within the flash zone, and spray nozzles located within the flash zone above the coke drum vapor inlet;

b. removing a light coker gas oil stream from the fractionating column via the light coker gas oil draw;

c. removing a heavy coker gas oil stream from the fractionating column via the heavy coker gas oil draw;

d. introducing at least a portion of the heavy coker gas oil stream into the fractionating column, wherein the at least a portion of the heavy coker gas oil stream is introduced into the fractionating column below the heavy coker gas oil draw and above the heavy heavy coker gas oil draw;

e. withdrawing at least a portion of the heavy coker gas oil stream as an end product;

f. introducing a remaining portion of the heavy coker gas oil stream into at least one heat exchanger, wherein upon exiting the heat exchanger the remaining portion of heavy coker gas oil stream is divided into a first stream and a second stream;

g. introducing the first stream into the fractionating column, wherein the first stream is introduced into the fractionating column above the heavy coker gas oil draw;

h. introducing the second stream into the fractionating column, wherein the second stream is introduced into the fractionating column at the heavy heavy coker gas oil draw;

i. removing a heavy heavy coker gas oil stream from the fractionating column via the heavy heavy coker gas oil draw; and

j. introducing the heavy heavy coker gas oil stream into the flash zone of the fractionating column, wherein the heavy heavy coker gas oil stream is utilized for the spray nozzles.

2. The delayed coking process according to claim 1 , wherein several fractionating trays below the heavy coker gas oil draw improve the separation between the heavy coker gas oil draw and the oil condensed in the flash zone.

3. The delayed coking process according to claim 1 , wherein the second stream is utilized to quench material removed at the heavy heavy coker gas oil draw.

4. The delayed coking process according to claim 1 , wherein the spray nozzles in the fractionating column function to condense the incoming streams,

5. The delayed coking process according to claim 1 , wherein at least a portion of the heavy coker gas oil stream of step (e) is sent as an end product to a stripper.

6. A delayed coking process comprising the following steps:

a. introducing coke drum vapors into a flash zone of a fractioning column of a delayed coking unit;

b. removing a heavy coker gas oil stream from the fractionating column via a heavy coker gas oil draw of the fractionating column;

c. withdrawing at least a portion of the heavy coker gas oil stream as an end product;

d. introducing at least a portion of the heavy coker gas oil stream into the fractionating column;

e. introducing a remaining portion of the heavy coker gas oil stream into at least one heat exchanger, wherein upon exiting the heat exchanger the remaining portion of the heavy coker gas oil stream is divided into a first stream and a second stream;

f. introducing the first stream into the fractionating column;

g. introducing the second stream into the fractionating column;

h. removing a heavy heavy coker gas oil stream from the fractionating column via a heavy heavy coker gas oil draw; and

i. introducing the heavy heavy coker gas oil stream into the flash zone of the fractionating column.

7. The delayed coking process according to claim 6 , wherein the delayed coking unit includes a coker furnace, at least two coke drums, a coke transfer line extending from the coker furnace to the coke drums, a fractionating column having multiple separation trays, and a coke drum vapor line extending from the coke drums to the fractionating column, wherein the fractionating column.

8. The delayed coking process according to claim 7 , wherein the fractionating column having multiple separation trays is a cylindrical shaped vessel.

9. The delayed coking process according to claim 6 , wherein the fractionating column is defined by sidewalls, a bottom end, and an upper end, wherein the fractionating column includes a light coker gas oil draw, a heavy coker gas oil draw located below the light coker gas oil draw, a heavy heavy coker gas oil draw located below the heavy coker gas oil draw, a flash zone located below the heavy heavy coker gas oil draw, a coke drum vapor inlet located within the flash zone, and spray nozzles located within the flash zone above the coke drum vapor inlet.

10. The delayed coking process according to claim 9 , wherein the at least a portion of the heavy coker gas oil stream is introduced into the fractionating column below the heavy coker gas oil draw and above the heavy heavy coker gas oil draw.

11. The delayed coking process according to claim 10 , wherein the first stream is introduced into the fractionating column above the heavy coker gas oil draw.

12. The delayed coking process according to claim 10 , wherein the second stream is introduced into the fractionating column at the heavy heavy coker gas oil draw.

13. The delayed coking process according to claim 10 , wherein the heavy heavy coker gas oil stream is utilized for the spray nozzles.

14. The delayed coking process according to claim 6 , wherein at least a portion of the heavy coker gas oil stream of step (e) is sent as an end product to a stripper.