Combustion Flashcards
What is the definition of combustion?
Combustion is defined as a chemical process in which a combustible unites with oxygen producing heat and often light.
Why is excess air required?
Excess air is required for complete combustion.
What are the combustion in fuel?
Carbon, hydrogen and sulphur are the combustibles in fuel.
Of what value is nitrogen in the combustion process?
As an inert gas, nitrogen has no value in the combustion process.
What is the greatest heat loss in the boiler?
Heat loss out of the stack is the greatest loss in a boiler.
How is #6 fuel oil atomized?
6 oil is atomized by rotary cup (mechanical) burners, pressure atomizing burners and steam/compressed air burner.
How mane gallons in barrel of #6 oil?
There are 42 gallons in a barrel of #6 oil.
At what temperature is #6 oil preheated before firing?
6 needs to be preheated to 160-210F.
What is the definition of draft?
Draft is defined as the pressure difference between to points that causes air or gas to flow.
Do package fire tube boilers purge automatically on start-up?
All boilers purge automatically when started.
What is the definition of flame impingement?
Flame impingement occurs when the flame touches boiler surface. This can lead to erosion of refractory and chemical contaminants contacting boiler metal surfaces.
Is the purge cycle the same for both #6 oil and gas?
The purge cycle, eight (8) volume air changes, is the same for all boilers.
Which 2 (two) combustible have the most heat value?
Hydrogen (62,000 btu/lb) and carbon (14,600 btu/lb) have the highest heat value.
What would cause a sudden increase in exit gas temperature?
A loss of boiler baffles(s) will allow flue gas to “short circuit” and cause a sudden increase in exit gas temperature.
Induce draft and forced draft fans are examples of what?
The use of fans in the combustion process is known as mechanical draft (vs. natural draft)
