MODULE 2 Operate the Propane Liquid Supply System

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.

LESSON 1 Open the Liquid Supply Line

Open the Liquid Supply Line

Liquid Outlet Valve Configurations

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

Emergency Shutoff Mechanisms Mechanical Latch Pneumatic Latch

Emergency Shutoff Mechanisms Fusible Elements – Built into ESV

Emergency Shutoff Mechanisms Fusible Elements – Remote Manual Close

Emergency Shutoff Mechanisms Remote Open and Close ESV with Pneumatic Operator Internal Valve with Pneumatic Operator

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.

Operating a Manual Shutoff Valve Multi-turn Globe valves Gate valves 90° turn Ball valves

Precautions Before Opening Valves

Open the Supply Line to the Pump

Discovery – What’s in Your Plant?

Lesson 2 How an Excess Flow Valve Works in a Liquid Line

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.

What Makes it Close?

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.

Check for Understanding

Lesson 3 Detecting Contamination in Stored Propane

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

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.

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 4 Operate with Multiple Storage Tanks of Different Diameters

Lesson 4 – Operate with Multiple Storage Tanks of Different Diameters Filling Levels Aligned Filling Levels Not Aligned

Check Your Understanding See page 13 of student guide for Module 1 quiz.

Lesson 5 Shut Down and Secure the Liquid Supply System

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.

Case Study – Securing the Liquid Supply System

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.