ADAPT

1
Mechanism of Coking In LTCs Unraveled A New
Diagnostic Tool Developed
ADAPT
H 2 b
TJ
By Leo Savio, Dave Hanson, and Russ Crutcher
2
COKING FAILURES
ADAPT
H 2 b
TJ

• Failures Attributed to Coking

3
WHAT WE FOUND
ADAPT
H 2 b
TJ

• Coke Can Be A Symptom
• Loose or Poor Contact
• Wear
• Misalignment
• Design Limits

4
WHAT WE FOUND
ADAPT
H 2 b
TJ

• Coke Can Be A Cause
• Chemical Films

5
CHARACTERIZING FILMS
ADAPT
H 2 b
TJ

• Oxides and Sulfides of Copper Always at Base of
  Films

Chalcocite
Tenorite
Cuprite
6
CHARACTERIZING FILMS
ADAPT
H 2 b
TJ
Coke
CuO

• Cooler Area

Cu2S
Void
Coke
7
LABORATORY DUPLICATION
ADAPT
H 2 b
TJ

• Special Test Cell
• 32 Liter Capacity
• Observation Port
• Simulated Contact
• Copper Rod
• Internally Heated
• Externally Monitored

8
LABORATORY DUPLICATION
ADAPT
H 2 b
TJ
001-001

• 001-001 Used Oil Test

004-002

• 004-002 a a a Arced Oil

9
LABORATORY DUPLICATION
ADAPT
H 2 b
TJ

• Copper Oxides
• Organized Carbon Films

10
NEW TOOL
ADAPT
H 2 b
TJ

• Test Chamber
• 32,000 mls of Oil
• 48-Hour Run
• Micro-Cell
• 10 mls of Oil
• 3-Hour Run

11
NEW TOOL
ADAPT
H 2 b
TJ

• Oils Differ
• 10 Minute Films
• 3 Hour Films
• No Films
• Films Differ
• Flaking Films
• Frothy Films
• Tough Films

12
NEW TOOL
ADAPT
H 2 b
TJ

• Blue Film 1
• Sharp Peaks
• High C-H
• Red Film 2
• Broad Bands
• Little C-H

13
SEARCH FOR PRECURSORS
ADAPT
H 2 b
TJ

• Arc Heating Creates a Variety of Poly-Aromatic
  Compounds

14
QUANTITATIVE ANALYSIS
ADAPT
H 2 b
TJ

• Real-Time Photometry
• Rate of Change (Internally Normalized)
• Adjustable Scale (Sensitivity can be Easily
  Adjusted)
• Potential for Automation
• Field Test Unit Potential

15
Micro-Cell 14
ADAPT
H 2 b
TJ
16
Micro-Cell 18
ADAPT
H 2 b
TJ
17
COKING POTENTIAL
ADAPT
H 2 b
TJ

• What is Coking Potential
• Quantitative Measure of Liquid Phase Diagnostics
• Gas Phase DiagnosticsWhat is Happening
• Liquid Phase Coking PotentialWhat will Happen
  Next

18
COKING POTENTIAL
ADAPT
H 2 b
TJ

• When is it Applied
• When Gas Phase Diagnostics Indicate Heating
• Ethylene/Acetylene Ratio Increases by 20

(Ethylene/Acetylene)NEW gt 1.2 X
(Ethylene/Acetylene)OLD
19
COKING POTENTIAL
ADAPT
H 2 b
TJ

• Implementation

Dissolved Gases Condition Code
Yes
No
Coking Potential Code
Yes
No
Increased Sampling Frequency
No Adjusted Sampling Frequency
20
COST SAVINGS
ADAPT
H 2 b
TJ

• Sampling Frequency Extended for Most Units
• Time Required for Sampling Avoided
• Unnecessary Analytical Costs Avoided
• Potential Coking Units Identified
• Problem Units Identified and Monitored More
  Closely
• Corrective Action Taken Before Problems Arise

21
CONCLUSION
ADAPT
H 2 b
TJ

• New Diagnostic
• Improved Monitoring
• Can be Automated
• Inexpensive Field Test

22
PROJECT OPPORTUNITY
ADAPT
H 2 b
TJ

• Need to Validate in Active LTCs