System and method for on-line spalling of a coker

• US 20070158240A1
• Filed: 01/08/2007
• Published: 07/12/2007
• Est. Priority Date: 01/09/2006
• Status: Active Grant

• Current Assignee: Alliance Process Partners, LLC
• Original Assignee: D-COK, LP
• Inventors: Gregory, Robert
• Granted Patent: US 7,597,797 B2
• Time in Patent Office: Days
• US Class Current: 208/131
• CPC Class Codes: C10G 9/005 Coking (in order to produce liquid products mainly)
• CPC Class Codes: C10G 9/20 Tube furnaces
• CPC Class Codes: C10G 9/206 controlling or regulating the tube furnaces
• CPC Class Codes: F28D 2021/0022 for chemical reactors
• CPC Class Codes: F28D 7/16 the conduits being arranged in parallel spaced relation F28D7/0008 - F28D7/0058 take precedence; F28D7/02 - F28D7/10 take precedence
• CPC Class Codes: F28F 27/02 for controlling the distribution of heat-exchange media between different channels static flow control means in header boxes F28F9/026; arrangements of guide plates or guide vanes F28F9/22, F28F25/12
• CPC Class Codes: F28G 9/00 Cleaning by flushing or washing, e.g. with chemical solvents appliances using jets of fluid for removing debris F28G1/16, F28G3/16

Abstract

Coker heater operation is improved by on-line spalling of coker heater pipes. In one embodiment an off-line pipe is added to the on-line coker heater pipes. When an on-line pipe is to be spalled, flow is diverted to the off-line pipe allowing for full operation of the coker heater. In another embodiment, a thermal transfer resistant zone plate is movably mounted in the radiant section of the coker heater. By moving the zone plate from an operating position to a spalling position and adjusting the temperature of the plurality of burners, the temperature of the pipes in the zone of the heater radiant section to be spalled can be lowered, while the temperature in the remaining zones of the heater radiant section are fully operational.

Claims

1. A system for on-line spalling of a pipe adapted for use with a coker heater comprising:

a plurality of on-line pipes positioned in the coker heater;

an off-line pipe positioned in the coker heater;

a first valve moving between an open position and a closed position for controlling the flow of liquid hydrocarbons to one of said plurality of on-line pipes; and

a second valve moving between an open position and a closed position for controlling the flow of liquid hydrocarbons to said off-line pipe whereby when said first valve is in the closed position for spalling said one of said plurality of on-line pipes, the second valve is in the open position for flow of liquid hydrocarbons.

2. The system of claim 1 wherein said plurality of pipes are in a horizontal orientation.

3. The system of claim 1 wherein said plurality of pipes are in a vertical orientation.

4. The system of claim 1 wherein said first valve and said second valve are a diverter valve.

5. The system of claim 4 wherein said diverter valve is a three-way valve.

6. A method for on-line spalling of a pipe adapted for use with a coker heater comprising the steps of:

flowing liquid hydrocarbons through a plurality of on-line pipes in the coker heater; and

diverting said liquid hydrocarbon through an off-line pipe positioned in the coker heater while one of said plurality of on-line pipes in the coker heater is being spalled.

7. A system for on-line spalling of a pipe adapted for use with a coker heater having a radiant section comprising:

a plurality of pipes positioned in the coker heater radiant section;

a plurality of spaced apart burners positioned in the coker heater radiant section; and

a zone plate movable between an operating position and a spalling position for insulating a pipe to be spalled from the heat of some of the burners.

8. The system of claim 7 wherein said zone plate is a thermal transfer resistant barrier.

9. The system of claim 7 wherein said zone plate is pivotable.

10. The system of claim 8 wherein said zone plate is fabricated from chrome.

11. The system of claim 7 wherein the temperature of each of the plurality of burners is set relative to the position of said zone plate to lower the temperature to the zone where the pipe is to be spalled.

12. The system of claim 11 wherein the temperature of each of the plurality of burners are adjustable.

13. A method for on-line spalling of a pipe adapted for use with a coker heater comprising the steps of:

positioning a zone plate in a radiant section of the coker heater;

moving the zone plate from an operating position to a spalling position;

reducing the temperature to a zone defined by said zone plate for the pipe to be spalled; and

maintaining the desired temperature in the other zone of said radiant section defined by said zone plate for another pipe.

14. The method of claim 13, further comprising the step of:

spalling the pipe in the reduced temperature zone.

15. The method of claim 13 wherein the step of reducing the temperature comprises lowering the heat transferred from a burner positioned below the reduced temperature zone.

16. The method of claim 13 wherein the zone plate spans approximately two-thirds the height of the radiant section of the coker heater.

17. The method of claim 13 wherein the radiant section of the coker heater comprises at least three burners.

18. The method of claim 17 wherein the zone plate is pivoted so that one end of the zone plate moves from above a burner positioned between the other burners to a position where said end of the zone plate is above the burners with one burner on one side and two burners on the other side.

19. The method of claim 18 wherein the burner on one side of the pivoted zone plate is turned off.

20. The method of claim 19 wherein the zone plate can be pivoted and locked and the burner can be operated from a remote location.