Spray dryers have many advantages. Which one of the following is NOT an advantage of a typical spray dryer?
Show Hint
- Has short drying time
- Produces hollow spherical particles
- Has high heat efficiency
- Is suitable for heat sensitive materials
The Correct Option is C
Solution and Explanation
Spray dryers atomize liquid into fine droplets, which dry rapidly in a hot gas stream to form powder particles.
Step 2: List actual advantages of spray dryers.
- They provide very short drying time (milliseconds to seconds).
- They produce fine hollow spherical particles, useful in many industries.
- They can handle heat-sensitive materials due to rapid evaporation cooling.
Step 3: Identify the non-advantage.
Spray dryers are not very efficient in terms of heat usage because a large fraction of hot air exits with unused heat.
Thus, the statement “Has high heat efficiency” is NOT an advantage.
\[ \boxed{(C) \; \text{Has high heat efficiency}} \]
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