TSBC External Feedwater Treatment Flashcards
A continuous blow-off is
a) used to reduce the dissolved gases in the boiler
b) installed in the steam drum
c) used on every boiler
d) installed in the lower drum
e) used to reduce sludge
b) installed in the steam drum
Chemicals are fed to a water tube boiler
a) with a small centrifugal pump
b) into the top drum only
c) with a small positive displacement pump
d) into the bottom drum only
e) prior to operating the blow off valves
c) with a small positive displacement pump
When performing a water test be sure that:
1. all equipment is clean and in good working order
2. results are recorded carefully before making the test
3. test solutions, indicators, and reagents are fresh,
and at full strength
4. test reagents are filtered before use
a) 1, 2
b) 2, 3
c) 1, 3
d) 2, 4
e) 3, 4
c) 1, 3
Titrating is done with
a) a titrant
b) a zeolite
c) an antifoam
d) trisodium phosphate
e) a reagent
e) a reagent
Phenolphthalein is
a) an indicator
b) a reagent
c) a buffer
d) an acid softener
e) neutralizing agent
a) an indicator
When used as a term during boiler water testing, DS means
a) demineralized steam
b) drain solids
c) dissolved solids
d) dissolved sulphite
e) depleted salts
c) dissolved solids
Boiler water testing is done in the average power plant every
a) shift
b) week
c) month
d) time the boiler inspector requests it
e) time the chief engineer requests it
a) shift
Total alkalinity is measured
a) using methyl orange indicator and N50 sulphuric acid
b) to be sure that it is not more than 2500 ppm
c) to keep a check on the dissolved oxygen
d) to control sludge formation
e) by using phenophthalein and N50 sulphuric acid
a) using methyl orange indicator and N50 sulphuric acid
The conductivity meter is used to measure the
a) current
b) alkalinity
c) electrolyte
d) voltage
e) TDS
e) TDS
A residual of 20 to 40 ppm of sodium sulphite is to
be maintained in the boiler water to
a) keep down the sludge
b) prevent pitting in the boiler steam drum
c) prevent scaling the float in the low water cut-off
d) keep feed water lines free of algae
e) reduce the total chemical consumption
b) prevent pitting in the boiler steam drum
Boiler water chemicals are injected
a) in measured amounts once per year
b) after considering the water test readings
c) into the water softener
d) to prevent the water becoming too alkaline
e) each time after blowing down
b) after considering the water test readings
When conducting a TDS or Total Dissolved Solids test, the impurity which has a high conductivity and must be neutralized is a) sodium phosphate b) hydroxide alkalinity c) pH d) suspended solids e) sodium chloride
b) hydroxide alkalinity
The methyl orange or "M" alkalinity test indicates alkalinity a) due to carbonates only b) due to bicarbonates only c) due to hydroxides only d) caused by all dissolved impurities contributing to alkalinity e) due to organics only
d) caused by all dissolved impurities contributing to
alkalinity
The phenolphthalein or "P" alkalinity test does not indicate alkalinity due to a) hydroxides b) bicarbonates c) sulphates d) carbonates e) phosphates
b) bicarbonates
Alkalinity in boiler water may be due to calcium, sodium or
magnesium
a) hydroxides
b) carbonates and bicarbonates
c) bicarbonates
d) hydroxides and bicarbonates
e) hydroxides, carbonates and bicarbonates
e) hydroxides, carbonates and bicarbonates
Raw water has hardness due to
a) the salts of calcium and magnesium
b) suspended solids
c) organic material
d) dissolved gases
e) phosphates
a) the salts of calcium and magnesium
The water in a boiler should be kept
a) alkaline
b) neutral
c) acidic
d) at a pH of 14
e) at a pH of 7
a) alkaline
One element which leads to caustic embrittlement in boiler tubes is
a) concentration of sodium hydroxide
b) concentration of sodium chloride
c) overheating of boiler parts
d) concentration of sodium sulphite
e) excessive boiler pressure
a) concentration of sodium hydroxide
To prevent scale formation, inject
a) zeolite
b) sodium chloride
c) phenolphthalein
d) amines
e) phosphates
e) phosphates
The pH of the boiler water should be maintained at
a) neutral
b) slightly alkaline
c) 11.5
d) 10.5
e) 7
d) 10.5
The boiler blowoff should be used to
a) reduce steam pressure
b) reduce feedwater pressure
c) control the total dissolved solids
d) prevent scale formation
e) expel the sodium sulphite
c) control the total dissolved solids
Sodium sulphite is used in boilers to
a) prevent scale formation
b) prevent carryover
c) control dissolved solids
d) prevent oxygen corrosion
e) prevent foaming
d) prevent oxygen corrosion
Return line corrosion
a) can be controlled by feeding sodium bicarbonate
b) can be prevented by adding sodium phosphate
c) can be prevented by adding sodium sulphite
d) can be controlled by feeding amines
e) can be controlled by adding polymers
d) can be controlled by feeding amines
Sodium sulphite chemical will
a) prevent corrosion due to oxygen in the boiler water
b) precipitate with calcium and magnesium
c) prevent scale adhering to the tubes
d) control foaming
e) control return line corrosion
a) prevent corrosion due to oxygen in the boiler water
Foaming of water in the boiler
a) is due to a high concentration of dissolved gases
b) can be controlled by adding sodium phosphate
c) can be controlled by adding more neutralizing amines
d) can be controlled by adding sulphur to the feedwater
e) can be controlled by the bottom and continuous blow downs
e) can be controlled by the bottom and continuous blow downs