Applications
Direct
buried applications
When containment is optional, but detection
is not.
For some applications such as fueling systems and transport
oil pipelines, a sensor system that detects small leaks
in the piping may be preferable or more economically
viable compared to a full double containment piping system,
dependent on regulatory consent.
 This
is a typical installation showing the main fuel oil carrier
pipe and the laser slotted PVC conduit located side by
side in the trench. Standard backfill and compaction
is used to cover the pipe and conduit. TraceTek TT5000
fuel oil sensor cables are later pulled into the conduit.
How
It Works
The amount of backfill contaminated in the first 24 hours is not that large,
even for a leak rate of 10 liters per hour (2.6 GPH).
Because the native compacted soil is less porous than the back fill in the trench,
the leak will tend to saturate the backfill faster than it leaches into the surrounding
soil.
Every trench/backfill/moisture combination is a little different. These test
results show the general concept and point out that in the early stage of a small
leak there is not a huge volume of soil contamination.
The trench become quite saturated hours or days before the spill is visible on
the surface or has spread too deeply underground or laterally.
The liquid fuel in the backfill is drawn into the slotted conduit via capillary
action. The TT5000 is such a good scavenger of liquid hydrocarbons that detection
occurs even when there is not an abundance of flowing fuel in the soil. The TT5000
ignores the presence of groundwater.
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Time = 15 Minutes
Leak Rate = 10 litres/hr
Spill Size = 2.5 litres
Cont. Soil = 0.007 m 3
@ 66% Solids |
|
|
Time = 3 Hours
Leak Rate = 10 litres/hr
Spill Size = 30 litres
Cont. Soil = 0.09 m 3
@ 66% Solids |
|
|
Time = 10 Hours
Leak Rate = 10 litres/hr
Spill Size = 100 litres
Cont. Soil = 0.3 m 3
@ 66% Solids |
|
|
Time = 20 Hours
Leak Rate = 10 litres/hr
Spill Size = 200 litres
Cont. Soil = 0.6 m 3
@ 66% Solids |
Jet
fuel transfer line with blue PVC slotted conduit
for TT5000 installed at a major international airport.
The TraceTek system reports a leak to an accuracy
of +- 1 metre along the length of a pipeline.
Containing the sensing cable within a conduit allows
for removal and inspection of the cable for simple
and direct verification of a leak before digging.
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