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2008 Coking.com Safety Seminar29 Sep - 2 Oct, 2008 Köln, Germany
Cetek Dual Emissivity Ceramic Coating System for Coker Heaters
Target: Fired Heaters
• Essential – Majority of Processes are Endothermic
• However, an Often Neglected Necessity
• Energy Wasted
• Capacity Limited
Cetek Ceramic Coating Technology
• Fired Heater Applications
– Refractories (high emissivity coatings)• Radiant Heat Transfer Improvement• NOx Emission Reduction (up to 35%)• Ceramic Fiber Encapsulation
– Process Tubes• Elimination of oxidation, scaling & fouling• Conductive Heat Transfer Improvement
– Heat Flux Manipulation (Dual Emissivity Coating System)• Applications in Coking Sensitive Units• Productivity Improvements• Conductive Heat Transfer Control• Run Length Increases
Cetek Dual Emissivity Coating System- Coker Heaters
• Manipulation of heat flux distribution in single fired heaters.
• Ceramic Coating System application based on coking pattern of the fire box.
Cetek Dual Emissivity Coating System (US Patent # 6,626,663B1)
• Differential Emissivity Tube Coatings– Increase, or Decrease Absorbed Heat Flux– Protects Tubes in High Flux Zones– Reduces Maximum Skin Temperatures
• Reduction of Peak/Average Heat Flux Ratio in Single – Fired Heaters– Use of Coatings on Both Refractory and Tubes– Reduces Heat Flux on Fired Side of Tubes– Increases Heat Flux on Back Side of Tubes– Increases Useable Tube Surface Area
• Overall Improvement in Heat Transfer Efficiency – Productivity Improvements
Cetek Matrix Coating System Cetek Matrix Coating System ––Heat Flux manipulationHeat Flux manipulation
High Emissivity CoatingHigh Emissivity CoatingOn RefractoryOn Refractory
Matrix Coating SystemMatrix Coating SystemOn TubesOn Tubes
Matrix Coating System
IR Thermography Inspection Comparison, MiRO
500.0
900.0 °C
550
600
650
700
750
800
850
FLIR Systems
600.0
800.0 °C
650
700
750
FLIR Systems
Before Coating After Coating
Tube Skin Temperatures After Coating, MiRO
F-001: TMTs after ceramic coating was applied (adjusted for furnace duty)
540
550
560
570
580
590
600
610
620
630
640
24/3/06 13/4/06 3/5/06 23/5/06 12/6/06 2/7/06 22/7/06 11/8/06 31/8/06
TMT Increase Rate: 0.35°C/dayTMT Increase Rate: 0.86oF/day Before CoatingTMT Increase Rate: 0.63oF/day After Coating
Flue Gas & Bridge Wall Temperature, MiRO
Delayed Coker FurnaceBWT and Flue Gas Temp (adjusted to constant furnace duty)
350
375
400
425
450
475
500
3/4/2004 6/12/2004 9/20/2004 12/29/2004 4/8/2005 7/17/2005 10/25/2005 2/2/2006 5/13/2006 8/21/2006 11/29/2006
Flue
Gas
Tem
pera
ture
625
650
675
700
725
750
775
BW
T
Flue-Gas-TemperatureBWTStart of Typical Run Start of Run After Ceramic Coating
Project, April, 2007
Coker #2 Heater
Type:
Cabin, 2 Cell, 4 passesTotal 36 coils (26 radiant + 10 convection)
Design Duty:
77.74 MMBTU/hr
Limitation:
At full capacity, high BWT duringwarm-up & switch-in phases
Project, April, 2007
• New process tubes installed• Preparation for coating before installation
in heaters• Ceramic coating application in situ• Minimizes time & interference during t/a
Project, April, 2007
• Process Tube Surface Preparation– Erection of 2 climate controlled enclosures– Chemical cleaning of tubes– Blasting surface to White Metal spec.– Protecting tubes with plastic wrapping– Storage in low humidity enclosure until
required for installation in heaters
Blasting Tubes
Blasted to “White Metal” Spec.
Tubes Wrapped to Preserve “White Metal” Blast
Project, April, 2007
• Ceramic Coating Application– Climate control in heater cells– Dual emissivity tube coating system
application– High emissivity refractory coating system
application– Climate control until heater start-up
Wrapped Tubes Installed in Heaters
Matrix Coating System
Project, April, 2007
• Results
400.0
900.0 °C
450
500
550
600
650
700
750
800
850
FLIR Systems
Uniform Tube Surface Temperatures
No Oxidation
No Scale/Fouling
Lower Flue gas Temperature
Project, April, 2007
Note: The first 30 days are not representative because capacity was limited by other refinery contingencies
Bridgewall Temperature
0.40
0.45
0.50
0.55
31-50 51-90 91-110
days
°C B
rdgw
ll ce
ll A+
B /
Flow
rate
post coatpre coat
Project, April, 2007
Note: The first 30 days are not representative because capacity was limited by other refinery contingencies
Throughput
2500
2700
2900
3100
3300
3500
31-50 51-90 91-110
days
tpd post coat
pre coat
Project, April, 2007
• Summary of Results
– No BWT Limitation Under Higher Charge Rate– Over 6% Charge Rate Increase– Fuel Saving of 0.5%– Run Length Increase approx. 20%– Pay-back less than 3 months– Improved Heater Reliabilty
• Accurate identification of Coking, real tube skin temperature measurement by IR
Recommended