Module 3 Flashcards
What is added to Natural Gas to make it easier to detect by odour
Butyl Mercaptan
What is added to Propane to make it easier to detect by odour
Ethyl Mercaptan
What family are propane and natural gas part of?
Hydrocarbon family
What is the composition of natural gas
Methane 89.68%, Ethane 4.68%
What is the chemical formula for natural gas
CH4
What is the chemical formula for propane
C3H8
As a gas what is the relative density/ specific gravity of propane and gas
Natural gas - 0.55 Propane Gas 1.52
What is the specific gravity of natural gas liquid and propane
Natural gas liquid - 0.3 Propane 0.51
What is the boiling point of propane
-44 degrees F it will remain as a liquid
What is the boiling point of natural gas
-260 degrees F
What is the expansion rate of propane from liquid to vapour
1 to 270 times
What is the expansion rate of natural gas from liquid to vapour
1 to 600 times
To what percentage do retailers fill propane containers
80% at 60 degrees F
What is heating value (heat content)
The amount of heat energy released from burning of cubic ft of gas
What is a BTU
British Thermal Unit - The amount of heat required to raise 1 pound of water 1 degree F
What burns hotter, propane or natural gas
Propane
Propane produces 2520 BTU per cubic foot
Natural Gas produces 1000 BTU per cubic foot
What is the ignition temperature of Natural Gas
1300 degrees F
What is the ignition temperature of propane
920 degrees F
What are the limits of flammability for Natural Gas
4% to 15%
What are the limits of flammability for propane
2.5% to 9%
What is the air to fuel ratio for complete combustion for natural gas
10 cubic feet of air to 1 cubic foot of gas (10:1)
What is the air to fuel ratio for complete combustion for propane?
23.5 cubic feet of air to 1 cubic foot of gas (23.5:1)
On Assignment 2 it was rounded to 25:1
What is the maximum flame temperature for natural gas and propane
3600 degrees F
What is the flame speed for natural gas?
12” per second
What is the flame speed for propane?
32” per second
What is combustion?
The rapid oxidization of a fuel gas to produce light and heat
What is air comprised of?
80% nitrogen 20% oxygen
What type of air is premixed with gas prior to ignition?
Primary air
What type of air surrounds the flame for combustion?
Secondary air
What are the two types of air required for combustion?
Primary/Secondary air
What is the purpose of dilution air?
Cooling hot flue gas, nothing to do with the combustion process
What is the colour of luminous flame?
Yellow/orange
What colour is a bunsen flame?
Blue
What does a flame orange in colour mean?
bad fuel air mix
What is the purpose of excess air?
To ensure complete combustion
How much does 1 gallon of propane weigh?
5.1 lbs
What are the products of complete combustion?
CO2, water vapour, nitrogen, heat and light
Where do the products of complete and incomplete combustion go?
Outside.
What is the specific gravity of CO?
.96, similar to air
What are the products of incomplete combustion?
CO, water vapour, soot and aldehydes
What are the symptoms of CO poisoning?
Flu like symptoms with no fever.
What is combustion air?
Air required to complete the combustion process so as not to produce CO
What is primary air?
Air that is mixed with fuel prior to ignition. Enters through the air shutter
What is secondary air?
Air supplied to complete combustion, supplied around the flame.
What is flame lifting?
The burner is over fired, too much primary air, the burner is cold.
How are natural gas and propane transported?
Natural gas - pipeline
Propane - Tanks and cylinders.
Why is propane so much hotter burning than natural gas?
Propane has more carbon and hydrogen atoms
What is flashback?
When gas/air flow velocity is less than the flame speed.
