Question

Consider the statements in respect of vapor absorption and vapor compression refrigeration systems.

1. The former runs on low-grade energy.

2. The pumping work in the former is negligible since the specific volume of the strong liquid solution is small.

3. The latter uses an absorber while the former uses a generator.

4. The liquid pump alone replaces the compressor of the latter.
Which of these statements are correct?

1. 1 and 2
2. 1 and 3
3. 1 and 4
4. 2 and 4

Answer 1

Correct Answer - Option 1 : 1 and 2

Explanation:

S No.	Vapour compression System	Vapour Absorption System
1.	Main parts of the system are compressor, condenser receiver, refrigerant control device and evaporator.	Main parts of the system are generator, rectifier, condenser absorber and evaporator.
2.	For pumping work, a single device compressor is used.	The compressor is replaced by the pump, generator and absorber.
3.	Pumping work is higher because gas (vapour) has high specific volume.	Pumping work is negligible since the specific volume of the liquid solution is very small.
4.	This system is required to operate by prime movers like electric motor, diesel or petrol engine which consume high-grade energy.	This system is required to operate by heat energy which is a low-grade form of energy.
5.	This system has many moving parts, hence wear and tear takes place.	This system has no moving parts, hence the possibility of wear and tear is very less.
6.	This system is more efficient.	This system is poor efficient.