PLANT EQUIPMENT 4
an air preheater is
cost saving system used to heat the air before it enters the burner
What is the name of the inlet line to the lower (drum)header
downcomer
What is the name of the section of the boiler utilized to preheat feed water before it enters the main boiler system?
economizer section
An economizer preheats air usually by waste heat from flue gases.
false
The damper in a process furnace controls the amount of combustion air and excess oxygen in the burners.
false
the air register draft in a furnace
false
Which type of boiler passes hot gases through tubes to heat up and vaporize water?
fire tube boiler
the section of the furnace that reaches the highest temp is the
firebox
What results when a section of a furnace tube gets too hot from coke beginning to form?
flame impingement
Ensuring proper air concentration is critical because:
fuel burns cleaner and hotter if air mixture is correct, fuel burns poorly and cooler if air mixture is incorrect
If flames impinge on the tubes within a furnace what is likely to happen.
hot spots will begin to form
most fired furnaces use
natural gas , fuel oil
four draft types on furnace designs are:
natural, balanced, induced, mechanical
boiler load is most closely defined as a:
plants demand for steam
Furnaces are used in processes such as:
preheating process fluids
carbon deposits are most likely to be found in the:
radiant tubes
what is the primary method of heat transfer in the firebox of a boiler?
radiation
Process furnaces are insulated by a brick-like material called ____.
refractory
Flow moves in the opposite direction in these tubes.
riser and downcomer
the downcomer is connnected to
steam generating drum and mud drum
Steam that is separated from liquid water and heated to a higher temperature is called ________. This type of steam is usually used to drive turbines.
superheated
A steam trap that operates by opening or closing a bellows as the temperature changes. This movement opens and closes a valve.
thermostatic trap
What is the purpose of a steam trap?
to remove condensate
An air preheater heats air usually by using waste heat from flue gases.
true
Fired furnaces may have single or multiple burners mounted either in the floor or in the wall.
true
Scale buildup on the inside of boiler tubes is caused by dissolved solids in the boiler feed water. What can happen if the scale buildup goes unchecked?
tube rupture
Select three operating problems associated with steam generation.
tube rupture, flame impingement, soot buildup
steam is used in:
turbine drivers heat exchangers distillation column
what is a stoker used for?
used to burn solid fuels for heat energy
There are two types of boilers. They are _____ tube and ____ tube.
water and fire
Slugs of water can damage equipment and lead to a condition known as:
water hammer
What is normally the maximum rate of temperature change that should not be exceeded when a boiler or a furnace is started up or shut down?
150° per hour
Some furnaces and boilers are equipped with soot blowers. The purpose of the soot blower is to remove soot.
True
Fired furnaces come in three design types, select these three types.
box, cabin, cylindrical
the air register are located on the
burner
what is used to evenly distribute air and fuel vapors over an ignition source and into a boiler firebox
burner
When coke forms on the inside of the tubes of a fired furnace how is it normally removed the majority of the time?
by introducing superheated steam to burn off the coke
Carbon deposits found inside furnace tubes:
coking
As steam flows from the boiler to the plant it begins to cool and become a liquid. What is the technical name for this material?
condensate
tubes located above the shock bank
convection tubes