Method of cleaning a heater

• US 6,170,493 B1
• Filed: 10/31/1997
• Issued: 01/09/2001
• Est. Priority Date: 10/31/1997
• Status: Expired due to Term

• Current Assignee: Orlande Sivacoe
• Original Assignee: Orlande Sivacoe
• Inventors: Sivacoe, Orlande
• Primary Examiner(s): Gulakowski, Randy
• Assistant Examiner(s): CHAUDHRY, SAEED T
• Application Number:
  US08/961,574
• Time in Patent Office: 1,166 Days
• Field of Search: 134/8, 134/22.11, 134/22.12, 134/22.1, 165/5, 165/11.1, 165/279, 15/35, 15/35.1
• US Class Current: 134/8
• CPC Class Codes: B08B 9/0553 Cylindrically shaped pigs
• CPC Class Codes: F28D 2021/0059 for petrochemical plants
• CPC Class Codes: F28G 1/12 Fluid-propelled scrapers, bullets, or like solid bodies

Abstract

A method of cleaning tubing in an operating heater, in which the tubing has an inlet and an outlet. While the heater is in operation, a pig is run though the tubing from the inlet to the outlet and then returned to the inlet along return tubing, in parallel connection to the heater tubing. A combined pig launcher and receiver mounted parallel to the tubing, and controlled with three way full port valves, is used to launch pigs into the tubing and remove them from the tubing. A boost pump is used to force pigs back from outlet to inlet.

Claims

1. A method of cleaning tubing in an operating heater in a petrochemical installation, in which the tubing has an inlet and an outlet, the method comprising repeating the steps of:

(a) while the heater is in operation in the petrochemical installation, running a pig through the tubing from the inlet to the outlet, the pig being dimension to fit compressed within the tubing; and

(b) returning the pig to the inlet along return tubing, in parallel connection to the heater tubing, the return tubing being connected to a boost pump via a boost pump connection pipe to provide pressure for returning the pig to the inlet, and said return tubing being closed by return valve while the pig is running through the heater tubing, and the return valve is opened after the pig passes the boost pump connection pipe.

2. The method of claim 1 in which the return tubing is connected to the outlet of the heater at a junction, and an outlet valve is provided in the outlet downstream of the junction, and the method further comprises the step of:

closing the outlet valve after the pig passes the boost pump connection pipe.

3. The method of claim 2 in which, when a pig enters the inlet to the heater tubing, after passing through the return tubing, the return valve is closed and the outlet valve is opened.

4. The method of claim 1 in which a pig is launched into one of the heater tubing and the return tubing by use of a pig launcher mounted parallel to the one of the heater tubing and the return tubing.

5. The method of claim 4 further comprising removing the pig from one of the heater tubing and the return tubing with a pig receiver mounted parallel to the one of the heater tubing and the return tubing.

6. The method of claim 5 in which a single combined pig launcher and receiver functions as the pig launcher and the pig receiver.

7. A method of cleaning tubing in an operating heater in a petrochemical installation, in which the tubing has an inlet and an outlet, the method comprising:

(a) running a pig through the tubing from the inlet to the outlet while the heater is in operation in the petrochemical installation, the pig being dimensioned to fit compressed within the tubing;

(b) returning the pig to the inlet along return tubing, in parallel connection to the heater tubing,

(c) removing the pig from one of the heater tubing and the return tubing with a pig receiver mounted parallel to the one of the heater tubing and the return tubing; and

in which a boost pump is connected to the return tubing via a boost pump connection pipe to provide pressure for returning the pig to the inlet, and said pig being launched into one of the heater tubing and the return tubing by use of a pig launcher mounted parallel to the one of the heater tubing and the return tubing, and a single combined pig launcher and receiver functions as the pig launcher and the pig receiver, and the return tubing is closed by a return valve while the pig is running through the heater tubing, and the return valve is opened after the pig passes the boost pump connection pipe.

8. The method of claim 7 in which the return tubing is connected to the outlet of the heater at a junction, and an outlet valve is provided on the outlet downstream of the junction, and the method further comprises the step of:

closing the outlet valve after the pig passes the boost pump connection pipe.

9. The method of claim 8 in which, when a pig enters the inlet to the heater tubing, after passing through the return tubing, the return valve is closed and the outlet valve is opened.

10. A method of cleaning tubing in an operating heater in a petrochemical installation, in which the tubing has an inlet and an outlet, the method comprising repeating the steps of:

(a) while the heater is in operation in the petrochemical installation, running a pig through the tubing from the inlet to the outlet, the pig being dimensioned to fit compressed within the tubing; and

(b) returning the pig to the inlet along return tubing, in parallel connection to the heater tubing, and the temperature of the fluid flowing through the tubing is in excess of 500°

F.

11. The method of claim 10 in which the heater has a convection section and a radiant section, and the pig is run through tubing in both the convection section and the radiant section.

12. The method of claim 10 in which the pig is made entirely of metal.

14. The method of claim 11 in which the heater has a convection section and a radiant section, and the pig is run through tubing in both the convection section and the radiant section.

15. The method of claim 11 in which the pig is made entirely of metal.

13. A method of cleaning tubing in an operating heater in a petrochemical installation, in which the tubing has an inlet and an outlet, the method comprising running a pig through the tubing from the inlet to the outlet while the heater is in operation in the petrochemical installation, the pig being dimensioned to fit compressed within the tubing, and returning the pig to the inlet, and the temperature of the fluid flowing through the tubing is in excess of 500°

F.

16. A method of cleaning tubing in an operating heater in a petrochemical installation, the tubing having an outlet and an inlet, the method comprising the steps of:

(a) operating the heater in a petrochemical installation with the fluid to be heated flowing through the tubing at a temperature in excess of 500°

F.; and

(b) selectively cleaning the operating heater while the fluid to be heated flows through the tubing, by;

(i) launching a pig into the tubing of the heater;

(ii) running the pig through the tubing of the operating heater from the inlet to the outlet at least one pass, with the pig compressed within the tubing; and

(iii) removing the pig from the tubing of the operating heater.

17. The method of claim 16 in which the heater has a convection section and a radiant section, and the pig is run through tubing in both the convection section and the radiant section.

18. The method of claim 16 in which the pig is made entirely of metal.