dissolved oxygen
chlorides
sludge
dissolved nitrogen
第1题:
The water in an auxiliary boiler should be tested for chloride content to determine ( ).
A.total dissolved solids
B.salt contamination
C.water harcness
D.chlorine contamination
第2题:
The boiler water alkalinity in a coil-type auxiliary boiler should be maintained at the pH recommended by the boiler manufacturer to______.
A.precipitate(使沉淀) silica (硅石)from solution
B.reduce corrosion in the heating coil
C.prevent clogging and erosion in the coil
D.maintain zero water hardness
第3题:
The correct procedure for giving an auxiliary boiler a bottom blow, is to begin .
A.when the boiler has been secured long enough for most solids to settle
B.when the boiler has been cooled to ambient temperature
C.only after raising the water level to within 0.5 inch of the high water cutout only
D.after bypassing the low pressure
第4题:
The safety valve escape piping should be disconnected from the valve body and a blank inserted
The boiler vent valves should be opened
All hand-hole/manhole covers should be tightened up as much as possible to preclude any leaks
All of the above
第5题:
completed
carried out
cleaned
steamed
第6题:
If the feed pump for an auxiliary boiler fails to deliver the feed water to the boiler, the cause may be ______.
A.high steam pressure in the boiler
B.abnormally high feed-water temperature
C.abnormally high boiler water temperature
D.steam demand exceeding feed pump capacity
第7题:
concentrations of calcium sulfate in the boiler water
fuel oil in the feed water
improper treatment of the feed water with calcium sulfate
excessive feed water alkalinity
第8题:
A.salinity is abnormally
B.high steam demand is too
C.feed-water flow is low
D.water level is abnormally low
第9题:
will be modulated in proportion
will be modulated in proportion and integral
will be modulated in proportion and differential
will not be modulated at all
第10题:
operating the boiler at less than normal water level
installing fins on the firesides of water-tubes
increasing the amount of excess air to the burners
treating the boiler water with chemical oxygen scavengers