Recovered steam condensate is recycled as boiler feedwater because of its low___________________?
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Answer: D. All A., B. and C.
Explanation
Recovered steam condensate originates from condensed pure water vapor containing virtually no dissolved mineral impurities. Low hardness prevents the formation of hard calcium and magnesium scale deposits on internal boiler heat transfer surfaces. Negligible dissolved and suspended solids eliminate foaming, priming, and particulate fouling inside high pressure steam generators. Boiler feedwater quality is strictly regulated to prevent catastrophic equipment failures caused by corrosion and scale accumulation. Raw make-up water typically contains significant mineral hardness that requires expensive chemical softening treatments before use. Steam condensation leaves behind virtually all non-volatile impurities inside the primary steam utilization equipment.
Focusing exclusively on hardness ignores the critical need to eliminate dissolved and suspended solids from boiler feeds. Selecting only dissolved solids leaves out the equally dangerous presence of mineral hardness and suspended particulate matter. Choosing suspended solids alone neglects the fact that chemical hardness and dissolved minerals cause severe boiler scaling.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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