ICAR AICE-JRF/SRF Dairy Refrigeration & Cold Chain: practice questions

1 · Vapour compression cycle and coefficient of performance · easy

How many tons of refrigeration is 100 kW (1 TR = 3.517 kW)?

1. 100.0 TR
2. 12.0 TR
3. 28.4 TR
4. 351.7 TR

2 · Bulk milk coolers · medium

A bulk milk cooler must cool 2,060 kg of milk from 35 to 4 °C in 3 hours (cp 3.9 kJ/kg K). What average refrigeration capacity is needed, ignoring losses?

1. 23.1 kW
2. 69.2 kW
3. 3.0 kW
4. 26.0 kW

3 · Refrigerants and their environmental rules · medium

HFOs such as R1234yf are attractive because they have:

1. No flammability or pressure limits
2. High ozone depletion potential
3. Very low global warming potential
4. The same GWP as R404A

4 · Multi-pressure and ammonia systems · hard

In two-stage ammonia systems, intercooling between stages:

1. Adds water to the refrigerant
2. Removes the need for a condenser
3. Raises discharge temperature to aid oil return
4. Cools intermediate gas, cutting work

5 · Ice-bank and chilled-water systems · medium

Ice water from an ice bank is typically at about:

1. 0.5–1 °C
2. 10 °C
3. 4–6 °C
4. −10 °C

6 · Bulk milk coolers · easy

Pre-coolers using well water before the tank:

1. Replace cleaning
2. Reduce load
3. Freeze the milk
4. Increase energy use

7 · Psychrometry and air conditioning · medium

High-hygiene filling rooms are supplied with filtered air at:

1. 100% humidity
2. Positive pressure
3. Negative pressure
4. Zero ventilation

8 · Insulation and vapour barriers · medium

Why are freezer store floors heated or ventilated underneath?

1. To warm products
2. To dry the insulation
3. To prevent frost heave
4. To save refrigeration energy

9 · Hardening rooms and frozen storage · easy

Stock rotation in frozen stores usually follows:

1. Last-in, first-out
2. First-expiry, first-out
3. Random picking
4. Largest pack first

10 · Refrigerated transport and cold-chain monitoring · medium

The ATP Agreement concerns:

1. Milk pricing
2. ATP bioluminescence testing
3. International carriage of perishable foods
4. Ammonia plant safety