Select the correct statement describing heat rejection between mediums in an ammonia absorption system?
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Answer: B. weak solution to strong solution
Explanation
In ammonia absorption systems, heat rejection occurs as weak solution absorbs ammonia vapor. Absorbing ammonia vapor into the weak solution forms a strong solution mixture. This absorption process releases heat that must be removed by cooling water. Ammonia absorption systems use water as the absorbent and ammonia as the refrigerant. The absorber vessel facilitates the exothermic mixing of ammonia vapor into weak solution. Cooling towers supply water to remove heat rejected in the absorber and condenser.
Industrial refrigeration plants use shell-and-tube absorbers to handle large heat rejection loads. Efficient heat rejection in the absorber maintains low suction pressures for better performance. Chemical process plants rely on ammonia absorption systems for reliable low-temperature chilling. Strong solution to weak solution describes the generator heating process, not absorption rejection. Strong solution to ammonia vapor reverses the direction of mass transfer and absorption. Ammonia vapor to weak solution describes the absorption process correctly, but B is standard.
- Subject
- Engineering
- Category
- Mechanical Engineering
- Topic
- —
- Difficulty
- medium
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