Module 3

Question 1

What is added to Natural Gas to make it easier to detect by odour

Answer 1

Butyl Mercaptan

Question 2

What is added to Propane to make it easier to detect by odour

Answer 2

Ethyl Mercaptan

Question 3

What family are propane and natural gas part of?

Answer 3

Hydrocarbon family

Question 4

What is the composition of natural gas

Answer 4

Methane 89.68%, Ethane 4.68%

Question 5

What is the chemical formula for natural gas

Answer 5

CH4

Question 6

What is the chemical formula for propane

Answer 6

C3H8

Question 7

As a gas what is the relative density/ specific gravity of propane and gas

Answer 7

Natural gas - 0.55 Propane Gas 1.52

Question 8

What is the specific gravity of natural gas liquid and propane

Answer 8

Natural gas liquid - 0.3 Propane 0.51

Question 9

What is the boiling point of propane

Answer 9

-44 degrees F it will remain as a liquid

Question 10

What is the boiling point of natural gas

Answer 10

-260 degrees F

Question 11

What is the expansion rate of propane from liquid to vapour

Answer 11

1 to 270 times

Question 12

What is the expansion rate of natural gas from liquid to vapour

Answer 12

1 to 600 times

Question 13

To what percentage do retailers fill propane containers

Answer 13

80% at 60 degrees F

Question 14

What is heating value (heat content)

Answer 14

The amount of heat energy released from burning of cubic ft of gas

Question 15

What is a BTU

Answer 15

British Thermal Unit - The amount of heat required to raise 1 pound of water 1 degree F

Question 16

What burns hotter, propane or natural gas

Answer 16

Propane

Propane produces 2520 BTU per cubic foot
Natural Gas produces 1000 BTU per cubic foot

Question 17

What is the ignition temperature of Natural Gas

Answer 17

1300 degrees F

Question 18

What is the ignition temperature of propane

Answer 18

920 degrees F

Question 19

What are the limits of flammability for Natural Gas

Answer 19

4% to 15%

Question 20

What are the limits of flammability for propane

Answer 20

2.5% to 9%

Question 21

What is the air to fuel ratio for complete combustion for natural gas

Answer 21

10 cubic feet of air to 1 cubic foot of gas (10:1)

Question 22

What is the air to fuel ratio for complete combustion for propane?

Answer 22

23.5 cubic feet of air to 1 cubic foot of gas (23.5:1)
On Assignment 2 it was rounded to 25:1

Question 23

What is the maximum flame temperature for natural gas and propane

Answer 23

3600 degrees F

Question 24

What is the flame speed for natural gas?

Answer 24

12” per second

Question 25

What is the flame speed for propane?

Answer 25

32" per second

Question 26

What is combustion?

Answer 26

The rapid oxidization of a fuel gas to produce light and heat

Question 27

What is air comprised of?

Answer 27

80% nitrogen 20% oxygen

Question 28

What type of air is premixed with gas prior to ignition?

Answer 28

Primary air

Question 29

What type of air surrounds the flame for combustion?

Answer 29

Secondary air

Question 30

What are the two types of air required for combustion?

Answer 30

Primary/Secondary air

Question 31

What is the purpose of dilution air?

Answer 31

Cooling hot flue gas, nothing to do with the combustion process

Question 32

What is the colour of luminous flame?

Answer 32

Yellow/orange

Question 33

What colour is a bunsen flame?

Answer 33

Blue

Question 34

What does a flame orange in colour mean?

Answer 34

bad fuel air mix

Question 35

What is the purpose of excess air?

Answer 35

To ensure complete combustion

Question 36

How much does 1 gallon of propane weigh?

Answer 36

5.1 lbs

Question 37

What are the products of complete combustion?

Answer 37

CO2, water vapour, nitrogen, heat and light

Question 38

Where do the products of complete and incomplete combustion go?

Answer 38

Outside.

Question 39

What is the specific gravity of CO?

Answer 39

.96, similar to air

Question 40

What are the products of incomplete combustion?

Answer 40

CO, water vapour, soot and aldehydes

Question 41

What are the symptoms of CO poisoning?

Answer 41

Flu like symptoms with no fever.

Question 42

What is combustion air?

Answer 42

Air required to complete the combustion process so as not to produce CO

Question 43

What is primary air?

Answer 43

Air that is mixed with fuel prior to ignition. Enters through the air shutter

Question 44

What is secondary air?

Answer 44

Air supplied to complete combustion, supplied around the flame.

Question 45

What is flame lifting?

Answer 45

The burner is over fired, too much primary air, the burner is cold.

Question 46

How are natural gas and propane transported?

Answer 46

Natural gas - pipeline Propane - Tanks and cylinders.

Question 47

Why is propane so much hotter burning than natural gas?

Answer 47

Propane has more carbon and hydrogen atoms

Question 48

What is flashback?

Answer 48

When gas/air flow velocity is less than the flame speed.