Transcript MODULE 1:
2011 PLANT OPERATIONS
MODULE 2
Operate the Propane Liquid Supply System
2011 PLANT OPERATIONS
Module 2 – Operate the Propane Liquid Supply System
In this module, you will learn to:
Identify and safely open the valves in the liquid supply
lines leading from the storage tanks.
Avoid unintentionally closing (slugging) an excess flow
valve.
Reopen an excess flow valve to resume liquid delivery.
Detect suspected contamination of stored propane.
Avoid potential problems when operating with multiple
storage tanks of different diameters.
Know when it is necessary to shut down and secure the
liquid supply system, and follow the proper procedure
to do so.
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LESSON 1
Open the Liquid Supply Line
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Open the Liquid Supply Line
LESSON 1
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Liquid Outlet Valve Configurations
LESSON 1
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Emergency Shutoff Mechanisms
ESV must be capable of being closed.
Automatically by thermal (fire) actuation.
Manually from a remote location.
Manually at the valve.
Open Position
Closed Position
LESSON 1
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Emergency Shutoff Mechanisms
Mechanical Latch
LESSON 1
Pneumatic Latch
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Emergency Shutoff Mechanisms
Fusible Elements – Built into ESV
LESSON 1
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Emergency Shutoff Mechanisms
Fusible Elements – Remote
Manual
Close
LESSON 1
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Emergency Shutoff Mechanisms
Remote Open and Close
ESV with
Pneumatic Operator
Internal Valve with
Pneumatic Operator
LESSON 1
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Emergency Shutoff Mechanisms
A bulk plant must have an emergency
shutdown system with:
A mechanical or pneumatic connection to
the internal valve, or to an approved
ESV, in the liquid line in each storage
tank.
One or more emergency remote
shutdown stations, each with a
mechanism to manually close storage
tank shutoff valves.
An emergency remote shutdown station
must be located between 25 and 100
feet from the transfer location.
LESSON 1
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Operating a Manual Shutoff Valve
Multi-turn
Globe valves
Gate valves
90° turn
Ball valves
LESSON 1
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Precautions Before Opening Valves
LESSON 1
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Open the Supply Line to the Pump
LESSON 1
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Discovery – What’s in Your Plant?
LESSON 1
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Lesson 2
How an Excess Flow Valve Works in a Liquid Line
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Lesson 2 – How an Excess Flow Valve Works in a Liquid
Line
Purpose - limit the flow of propane in the event of
an unsafe condition.
– Hose rupture or separation.
– Pipe breakage.
– Someone opening a hose end valve not
connected to a container.
Found at:
– Liquid outlet of propane storage tank.
– Where the pipe diameter is reduced.
– Sometimes at transfer points.
LESSON 1
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What Makes it Close?
LESSON 1
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How to Open It
Close the closest downstream manual
valve.
Wait patiently for the excess flow valve to
open - you may hear it click.
Open the valve SLOWLY to avoid a
sudden increase in flow.
LESSON 2
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Check for Understanding
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Lesson 3
Detecting Contamination in Stored Propane
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Lesson 3 – Detecting Contamination in Stored Propane
Potential hazards include:
Excessive pressure - discharge through pressure
relief valve.
Malfunction of fuel systems in propane-powered
vehicles.
Incomplete combustion in a forklift engine,
contaminating air inside a plant.
Health risk from release of contaminants into the
atmosphere.
Temperature/Pressure
Relationship
LESSON 3
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Temperature/Pressure Relationship for Propane
Exact composition may vary.
Pressure at any given temperature is
predictable for a particular composition with a
particular specific gravity.
LESSON 2
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Other Clues
Abnormal odor
A frost line on the container
Corrosion on brass or other yellow metals
Oily material appearing when a hose is
disconnected.
LESSON 2
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Lesson 4
Operate with Multiple Storage Tanks of Different Diameters
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Lesson 4 – Operate with Multiple Storage Tanks of Different
Diameters
Filling Levels Aligned
LESSON 3
Filling Levels Not Aligned
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Check Your Understanding
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Lesson 5
Shut Down and Secure the Liquid Supply System
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Lesson 5 – Shut Down and Secure the Liquid Supply System
When is Shutdown Necessary?
Shutdown Procedure:
– Make sure hose end valves are closed with dust
caps or plugs installed.
– Close liquid valve at storage tank outlet.
– Close liquid and vapor return valves.
– Secure transfer hoses.
– Close and lock cabinets, gates or valves.
LESSON 3
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Case Study – Securing the Liquid Supply System
LESSON 3
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Summary
Liquid supply systems vary. All must have valves that serve the following
functions:
–
–
–
–
Excess flow valve.
Emergency shutoff valve.
Manual shutoff valve.
An internal valve may serve all three functions.
An ESV must be capable of manual, remote and thermal shutoff.
A pump should have a bypass line to return excess liquid to the storage tank.
Always open the last valve slowly to avoid slugging an excess flow valve.
When operating with multiple storage tanks of different diameters, extra care
is required when their maximum permitted filling levels are not aligned.
Any time a propane liquid supply system will be left unattended it must be
shut down and secured.
LESSON 3
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