LNG Flashcards
LNG is shipped as __________.
cryogenic, MC338
LNG is cooled to its boiling point (__________) to be turned into liquid.
-260°F
LNG is non-odorized due to __________ freezing at -189°F.
mercaptan
During a liquid leak, vapors will stay __________ due to being cold and will rise while warming up.
low
Expansion ratio of LNG is __________.
600:1
Flammability range is __________.
5%-15%
Natural gas is transported as a __________ through pipelines in short distances.
gas
Primary concerns of LNG are __________ and __________.
asphyxiation, cryo burns
LNG is transported in __________ cryogenic containers.
MC338
Construction is double-walled containers with the inside being made of stainless steel (__________) and the outside of carbon steel with approx. __________ of insulation between layers.
9/16”, 6”
LNG can be transported over the __________, by __________, or by __________.
road, rail, ship
Some locomotives will use a __________ located directly behind the engine to be used as fuel.
nurse tanker
Rail tank cars can carry upwards of __________ gallons of LNG.
30,000
Over-the-road tankers can carry approx. __________ gallons of LNG.
12,000-16,000
Tank car specification markings: __________.
DOT113 C 120 W(9)
Over-the-road containers are rated for __________ days of storage before offloading is required.
20
Saddle tanks used as fuel are rated for __________ days before needing offloading or refill (approx. __________ miles).
5, 550-600
MAWP for MC338 is __________ psi.
70
Pressure relief valves are set to __________ psi.
75
No more than __________ psi allowed when filled prior to leaving fill stations for transport.
15
Allowed no more than __________ psi/day increase when transporting.
3
Rail transport = __________ or __________.
consist, waybill
Road transport = __________.
bill of lading
Marine transport = __________.
dangerous cargo manifest
Safety shut-offs are located on the __________ and __________ of containers.
right rear, front left
< or > __________% humidity will determine how visible a cloud will be during a liquid leak.
55
<55% humidity will __________ the hazard.
underestimate
> 55% humidity will approximate the __________.
flammable region
Do not apply __________ to a pool of LNG due to RPT (Rapid Phase Transition).
water
RPT is a violent __________/expansion that mimics an explosion.
reaction
Use __________ extinguisher to extinguish LNG fires.
dry chemical
Direct contact with LNG can cause severe __________ to skin and materials.
frostbite
Frostbite occurs due to extreme cold temperatures of LNG.
If LNG vapors are between __________ and __________% in air, they can ignite or explode if exposed to an ignition source.
5%, 15%
This range is critical for understanding the flammability of LNG vapors.
Initially, LNG vapors are __________ than air but become __________ than air as they warm up.
heavier, lighter
This property affects how LNG vapors disperse in different environments.
A __________ occurs when a pressurized vessel containing LNG catastrophically fails due to exposure to intense heat.
BLEVE
BLEVE stands for Boiling Liquid Expanding Vapor Explosion.
When LNG rapidly vaporizes upon contact with water, it causes a __________ that mimics an explosion.
Rapid Phase Transition (RPT)
RPT can create significant pressure waves similar to an explosion.
In confined spaces, LNG vapors can cause __________ by displacing oxygen.
asphyxiation
This is a serious risk in poorly ventilated areas.
Pure methane in LNG is __________, but it can displace oxygen and cause suffocation.
non-toxic
While non-toxic, the displacement of oxygen can lead to dangerous situations.
LNG is primarily composed of __________, with small amounts of ethane, propane, and nitrogen.
methane
Methane is the main component that defines the properties of LNG.
LNG is a __________, __________ liquid at cryogenic temperatures.
colorless, odorless
These properties make LNG difficult to detect without specialized equipment.
The boiling point of LNG is __________.
-260°F
This low boiling point is essential for maintaining its liquid state.
The expansion ratio of LNG is __________, meaning 1 unit of liquid becomes 600 units of vapor.
600:1
This ratio illustrates the significant increase in volume when LNG vaporizes.
The flammability range of LNG vapors in air is __________ to __________%.
5%, 15%
Understanding this range is crucial for safety measures in handling LNG.
The vapor density of LNG is __________, meaning cold vapors are initially heavier than air.
0.55
Vapor density affects how vapors accumulate in the environment.
The autoignition temperature of LNG is approximately __________.
1004°F
This temperature indicates when LNG can ignite without an external flame.
The flash point of LNG is __________.
-306°F
The flash point is critical for understanding the safe handling of LNG.
LNG does not mix with water but may form __________ upon contact with water due to rapid cooling.
ice
This ice formation can pose risks in emergency situations.
LNG vapor becomes __________ than air when warmed, dispersing more easily.
lighter
This change in density affects how vapors travel and disperse in the atmosphere.
