Internal Flashcards
The result of improper water treatment is…
- Caustic embrittlement
- Foaming
- Corrosion
- Scale
- Sludge
What chemical is often used to maintain proper alkalinity with in the boiler?
Sodium hydroxide
To prevent calcium and magnesium compounds from forming scale with in the boiler what chemicals are added?
- Sodium hydroxide
- sodium carbonate
- sodium phosphate
- sodium aluminate
What organic chemicals are added to the boiler water for sludge conditioning?
- starch
- tannin
- lignin
- alginates
What are the two chemicals used for chemical deaeration?
Sodium sulphite - Na2SO3
Hydrazine - N2H4
What is a disadvantage of adding sodium sulphite to water to remove oxygen?
It raises the dissolved solids concentration
What does carryover mean?
When there is too much foam in the boiler and foam as being sucked into the boiler steam outlet
How is return line corrosion caused?
By oxygen and/or carbon dioxide mixed with the moisture
What two chemicals can be added to return lines to reduce corrosion?
Amine
Filming amines
How do you amines reduce return line corrosion?
How do filming amines reduce return line corrosion?
Amines neutralize the oxygen and carbon dioxide and are evaporated with the steam
Filming amines produce a thin film around the inside of the return lines
What type of pump is used to feed chemicals into the boiler?
Positive displacement pump
What are the three types of chemical feeder’s?
Adjustable stroke pump
Closed bypass feeder
Gravity drip feeder
What types of water tests are the most common?
Hardness Alkalinity Dissolved solids pH Sodium sulphite Phosphate
How is water hardness caused and how can you test for it?
Impurities such as calcium and magnesium
Soap test and titration test
Phenolphthalein is a liquid used as a…
Indicator
