principles and properties of fuel gases Flashcards
Heat:
energy that causes atoms to move
Temperature is…
heat intensity of level of heat of a substance.
British thermal unit (BTU)
The amount of energy required to raise the temperature of 1 pound of water 1°F
Hydrocarbons
Hydrogen and carbon atoms make up hydrocarbon molecules
Example of
liquid hydrocarbon
Number two fuel oil
2 fuel oil
__% Carbon __%Hydrogen
85% carbon 15% hydrogen
Delivery of fuel (oil and gas) is measured in
Gallons
Naturally and propane gas are what type of hydrocarbons
Vapor hydrocarbons
Propane’s chemical make-up (C* H*)
C3 H8
Another name for propane (lp)
Liquefied petroleum
Natural gas is
__% methane
___% ethane
95% methane
5% ethane
(measured in cu.ft for delivery)
Define:
Cubic foot
Amount of gas that would occupy 1 cu. foot of space, at 60°F, saturated with water vapor, and under 30” w.c’s of pressure
Higher carbon content
Means more heat and the fuel is closer to a solid-state
what does more hydrogen content mean
more efficient but gives off less heat
Absolute zero
-460°F
Volume of gas
Gas does not have a fixed volume it expands to fill whatever container it is in
when a container is full of gas and you continue to fill it what happends?
Additional gas increases pressure and temperature b/c of compressive energy
What happens when gas expands
More pressure is exerted on all surfaces of the container
Atmospheric pressure
14.7 PSIA (Absolute) (at sea level)
Gauge pressure is measured in
(PSI)
a reading of 0 = atmospheric pressure
Pressure above atmospheric will register on the gauge
What is water column used for
To measure small pressures above or below atmospheric pressure
Water column device
Manometer
One PSI is equal to ___ inches of w.c
28”
when gas temperature increases the pressure or volume must do what
also increase and vice versa
The Pressure of natural gas from service supplier inside the service line before the regulator and meter should be…
8” w.c - 60 psi
interchangable names for service line
gas main and distribution line
pressure after service regulator and meter
between 3.5” w.c - 8” w.c
Pressures inside the building after the inside service regulator should be between __ and ___
3.5” wc - 5” w.c
Most appliances want minimum of ___(pressure) going to the gas valve for proper operation and manifold pressure
5” w.c
Manifold pressure of a natural gas appliance should be
3.5” w.c
Chemical make-up of ethane
C2H6
chemical make-up of methane
CH4
When butane is added to propane the chemical make up becomes C* H*
C4 H10
