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Safety and environmental standards for fuel storage sites
Final report
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Figure 34
Motor/Electrically operated valve final element
18 Use of supply pump: Figure 35 shows a supply pump that can be used as the final element
of an automatic trip system where it can be demonstrated that the gravitation feed through the
stopped pump does not continue with an unacceptable overfill rate. This system should be
followed with manual closure of an isolation valve.
Figure 35
Supply pump as final element
19 Multiple tanks:
Figure 36
Use of a single final element (valve or pump) to isolate multiple tanks. Any sensor trips the final element
‘Final
element’
Fuel feed from:
-
rail
-
ship
-
process
MOV
or
EOV
Logic
solver
‘Sensor’
high-high trip
L
Existing tank
Pump
Fuel feed from:
-
rail
-
ship
-
process
Starter
Logic
solver
‘Sensor’
high-high trip
L
Existing tank
‘Final
element’
fail closed
Fuel feed from:
-
rail
-
ship
-
process
L
L
‘Sensors’
high-high trips
L
Actuator
Logic solver
1ooM
Existing tank
farms