The function of an ice plant or ice factory is to make or form ice in large quantity and in large size. The ice making process is quite similar to the one we observe in a domestic refrigerator. The only difference lies in the ice making the stage. In the freezer compartment, the tray with water when it comes in contact with very low-temperature environment, becomes ice but in an ice plant which is a huge commercial factory, it uses separate ice making or ice freezing circuit. The cold is produced in one circuit and it is transferred to the water cans by another circuit.

• Ammonia: It is the primary refrigerant which takes heat from brine. This ammonia changes phase while moving in the circuit
• Brine: It is the secondary refrigerant which takes heat from the water and produces ice.

There are three main circuits of working medium in ice plant:

1. Refrigeration circuit: Ammonia as working medium which actually produces the cold by changes its phase at different location
2. Cooling water circuit: Cooling water as working medium to remove the heat of condenser
3. Brine circuit: Brine solution as working medium which transfers the cold from ammonia to water filled cans where ice is to be formed.

Construction

• Compressor: Its function is to increase the temperature and pressure of Ammonia vapor coming out from evaporator.
• Condenser: It liquefies the high-pressure and high-temperature Ammonia to high-pressure and high-temperature Ammonia. Here chilled water comes in contact with the high-pressure and high-temperature ammonia and provides the temperature for condensation. The heated water is pumped and again taken to circuit after it has been cooled at natural cooling tower
• Receiver: It is used to collect the liquid Ammonia from the condenser.
• Throttle Valve: It expands Ammonia coming out from receiver to low pressure.
• Evaporator: It vaporize the liquid Ammonia from throttle valve by extracting heat from 'brine' and hence brine gets cooled and this brine solution is recirculated to water tank containing 'ice cans filled with water' to absorb the heat of water to freeze it and make ice.

Working

• Low pressure and low-temperature Ammonia coming out from the throttle valve is vaporized by taking the latent heat from the brine. Hence brine gets cooled which is circulated in the brine circuit to freeze the water and forming an ice from water.
• This cooled brine further absorbs the heat from water and converts water to ice.
• Vaporized Ammonia is compressed to high pressure and temperature and passes from condenser.
• In condenser Ammonia is condensed by water circulated in cooling water circuit having a natural cooling tower. The condenser condenses the Ammonia by water coming from natural cooling tower.