Line B Combustion and Emissions

Question 1

Describe the relationship between the % values of CO2 and O2 in the flue gas when you adjust the air shutter on a fan-assist burner during set-up?

Answer 1

The greater the amount of excess air, the higher the % of O2 and the lower the % of CO2

Question 2

If three flue samples were taken, the first with 20% excess air, and the second with 32% excess air, and the third with 44% excess air which would contain the higher CO2 reading?

Answer 2

The sample with 20% excess air

Question 3

If a natural gas appliance and a propane appliance were firing at the same rate and under the same conditions, which would have the greater air requirements and which would have the greater percentage of CO2 in the flue products?

Answer 3

Both have the same air requirements, but propane has higher CO2

Question 4

When performing an analysis of the products of combustion using natural gas, what percentages of carbon dioxide and oxygen you would expect to find if the excess air is set at 30%?

Answer 4

8.3% CO2, 5% O2

Question 5

A gas appliance is firing at 5,400 Mbh on propane gas and condensing all water vapor to a liquid state. Calculate the capacity of water produced each hour in US Gallons.

Answer 5

38 US Gallons

Question 6

What is the formula for perfect (stoichiometric) combustion?

Answer 6

Fuel + O2 + N2 = CO2 + H2O + N2

Question 7

What is the formula for complete combustion?

Answer 7

Fuel + O2 + N2 + Excess Air = CO2 + H2O + N2 + Excess Air

Question 8

How does tertiary air control NOx emissions?

Answer 8

It slightly cools the flame

Question 9

What can be done to control NOX emissions from a burner?

Answer 9

Inject steam around the flame

Question 10

What can be used to control the combustion air for a burner system?

Answer 10

A Variable Frequency Drive or Electronically Commutated Motor

Question 11

List three factors that can create CO in the products of combustion?

Answer 11

Running too much fuel, not enough combustion air or a failing draft inducer

Question 12

What is the maximum air-free CO level allowed to be produced during combustion?

Answer 12

400 ppm

Question 13

How many pounds of CO2 are produced per hour from a 54,784,000 BTUH fuel oil fired boiler?

Answer 13

8765 lbs

Question 14

How many pounds of CO2 are produced per hour from a 7,312,000 BTUH natural gas fired boiler?

Answer 14

856 lbs

Question 15

According to legislation, how much ppm sulfur content does heating oil need to be below?

Answer 15

500 ppm

Question 16

What chemical compounds from combustion are collectively called SOX?

Answer 16

SO2 & SO3

Question 17

What are two results when NO2 reacts with other pollutants?

Answer 17

Ozone and Acid Rain

Question 18

What chemical compounds from combustion are collectively called NOX?

Answer 18

NO & NO2