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Pipeline Leak DetectionThe Problem:
How can we minimize environmental damage caused by small leaks in liquid fuel pipelines that go unnoticed for long periods?
The Solution:
High Sensitivity External Leak Detection (HSELD)
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What is an HSELD system?
• A system that operates independently of the pipeline
• A system that directly detects leaked liquid using a continuously distributed, high sensitivity sensor
• A system that monitors its own integrity and checks for leaks on a 24/7 basis
• A system that compliments existing flow based leak detection to minimize your leak risk exposure
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Periodic inspection and testing
• Periodic tightness testing
• Right of way over-flights / Line Patrol
• Smart pigs• Public discovery
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0.001 0.01 0.1 1
Leak Rate (% of flow rate)
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pill
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bls
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7days
30days
60days
Periodic Inspections
=
Environmental Protection Risk
At RISK !
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SCADA (Flow Based) Leak Detection
Detection time
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0% 1% 2% 3% 4% 5% 6%
Leak rate (% of flow)
Tim
e (m
inut
es)
• Response time is faster for higher leak rates
• Greater leak sensitivity leads to more risk of false alarms
• End User experience indicates good performance only down to about 1~2% of flow
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Spill size increases for slower leaks
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0.01 0.1 1 10Leak Rate (% of flow rate)
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etec
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At RISK !
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Combining SCADA with periodic testing helps but…
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0.001 0.01 0.1 1 10
Leak Rate (% of flow rate)
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HSELD
SCADA
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30days
60days
Periodic Inspections
Environmental Protection Gap
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At Risk area is substantially reduced by HSELD
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0.01 0.1 1 10
Leak Rate (% of flow rate)
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External Direct Measurement
Installed into PVC well screen pipe
High Sensitivity sensor cable
Positioned alongside the pipeline
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How it works
Animation based on 10 liter/hour leak rate (0.001% of flow), 66% solids
Time (hours)
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Detection at 21 hours
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Test results
Sample 1 Water Only
Sample 2Direct Fuel
Sample 3Sensor in sand
Sample 4Sensor in PVC
Sample 5Surface Test
Sample 6Water/Fuel Mix Test
Start Time 11:15 12:07 12:12 12:12 12:58 13:59
Start Temperature 15.5C 15.5C 15.5C 15.5C 15.5C 15 C
Alarm Time NO ALARMBy 18:30
13:13 13:24 13:35 14:16 15:15
Ending Temperature 15 C 15 C 15 C`
15 C 15 C 15 C
Elapsed Time 7:15 1:06 1:12 1:23 1:18 1:16
Total Fuel Used 1 liter H20 1 liter Jet A 8 liters Jet A 8 liters Jet A 10 cl Jet A poured into standing water puddle
Bucket packed with sand, 1 liter of Jet A at the bottom, water added to saturation
Fuel Rate:Amount / Interval
All at once All at Once 1 liter/ 10 min 1 liter/ 10 min
All at once All at Once
Alarm Panel Leak Location
N/A 1 m 9 m 9 m N/A 1 m
Measured Distance to Leak
N/A 1 m 9 m 9 m N/A 1 m
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Wilcox test details
Soil Type and Condition Water Table
Leak Position Time to Alarm
Location of Sensor Alarms
Course, Damp sand Above pipe
Above pipe @ center of test bed
5h 39m 6h 27m
10 o’clock@ 4 ft 12 o’clock@ 6 ft
Course, damp sand None Bottom of pipe@ center of test bed
6 h, No additional alarms during the 9 day leak
7 o’clock@5 ft
Fine, dry sandy soil None Bottom of pipe@ center of test bed
8 days No additional alarms during the 21 day leak
7 o’clock@ 7 ft.
Fine wet soil At bottom of pipe
Bottom of pipe@ center of test bed
2 h 3d 21 h
7 o’clock@ 5 ft. 10 o’clock@ 6 ft.
Fine, wet sandy soil Above pipe
Bottom of pipe@ center of test bed
1 d 12 h 12 o’clock@ 8 ft. (approx. center of tank)
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Project Design Considerations
• Trench style / construction
• Soil type
• Ground water conditions
• Degree of environmental protection required
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• Alongside buried single wall pipelines
• Around buried valves
• Under above ground storage tanks
• On airport hydrant fueling systems
• Anywhere you need to reduce risk in High Consequence Areas
Where can you use HSELD systems?
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Installation layout for pipeline
External Modbus Link to SCADA
Circuit 1 Circuit 2 Circuit 3 Circuit 4 Circuit 5 Circuit 6
120 VAC
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Regulatory Considerations
• Current regulations do not typically mandate leak detection to the level of HSELD protection
• API 1160 recognizes HSELD• Some environmental agencies have
formally recognized HSELD system• Public N.I.M.B.Y. campaigns are resulting
in greater efforts by operators to exceed regulatory requirements
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Florida State Approval
“…TraceTek TT5000leak detection system for single-walled underground bulk product piping will provide environmental protection substantially equivalent to that provided by compliance with the requirements established in Rules…”
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Third Party ValidationThird party testing of TT5000 “direct bury” system by Ken Wilcox Associates demonstrates that TraceTek works in single wall pipeline applications with Jet Fuel .
“In conclusion it must be noted that proper installation and positioning of the sensor, taking into account the local site conditions, is critical to reliable detection of leaks.”
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Summary
… fills the gap between SCADA and periodic testing
… Provides 24/7 environmental and system integrity monitoring
… Reduces emergency response time by pinpointing leak location
… Has been tested, proven and accepted by environmental authorities
… Substantially reduces operator risk in high consequence areas
TraceTek High Sensitivity External Leak Detection…