Bubble caps in distillation columns are positioned on trays with a pitch of ______________ times cap outer diameter?
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Answer: A. 1.3 to 2
Explanation
Distillation column design requires specific spacing between bubble caps to ensure proper vapor distribution. A pitch ranging from 1.3 to 2 times the outer diameter prevents vapor jet interference. This spacing ratio optimizes the available bubbling area across the entire tray deck. Bubble-cap trays facilitate intimate contact between ascending vapors and descending liquid phases. Tray performance depends heavily on uniform vapor flow through every individual cap unit. Improper spacing creates dead zones on the tray and reduces overall mass transfer efficiency.
Chemical plant designers rely on these empirical pitch guidelines when constructing fractionation columns. Optimized tray layouts prevent premature column flooding and enhance product separation purity. Distillation efficiency directly impacts energy consumption and operating costs in chemical processing. Option B provides a narrower range that excludes lower pitch values commonly used in compact designs. Option C specifies a single fixed value rather than the flexible engineering range required. Option D includes excessively wide upper limits that waste valuable distillation tray surface area.
- Subject
- Engineering
- Category
- Chemical Engineering
- Topic
- —
- Difficulty
- medium
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