An industrial chiller is a refrigeration system used to lower the temperature of machinery, industrial spaces, and process fluids by removing heat from the system and transferring it somewhere else. Industrial chillers are essential for temperature regulation in several industrial processes such as injection molding, metal plating, oilfield production, and food processing.
The Importance of Chillers
Chillers are vital in industrial settings. They move heat from the production process to outside of the facility. This is done when cool liquid circulates through process equipment or machinery that performs a specific task. Thus, the chiller keeps that cool liquid at the desired temperature.
The chilling process is highly beneficial to your operation. It protects equipment from too-high temperatures and cools your products during manufacturing. For this reason, chillers are used in many different industries. These include food and beverage, chemicals, injection molding, lasers, semiconductors, and tool and die cutting.
How Chiller Systems Work?
To put it simply, industrial chillers cool process fluids. Process fluids (typically water or a water/glycol mix) are used to cool machinery, equipment, food, etc. The process fluid absorbs heat from what is being cooled and then goes through the chiller where the heat is removed from the fluid and transferred to the ambient air.
A basic chiller has two circuits: the water circuit, and the refrigeration circuit:
In the water circuit, a pump circulates the water from the holding tank to the evaporator which cools the water by transferring the heat to a refrigerant, the water then goes on to the process in a portable chiller or back to the tank in a packaged or central chiller.
In the refrigeration circuit, the evaporator boils the liquid refrigerant into a gas cooling the water, the compressor increases the pressure of the refrigerant gas to a pressure (200 to 220 psi for freon 22) so that the condenser can condense the gas back to a liquid (remove the heat gained) using ambient air at 95° F or cooling tower water at 85° F.
In the case of an industrial chiller, the principle is the same. Water is pumped to the chiller normally at 60° F and cooled to 50° F, when using water/glycol solution can be cooled to 20° F. The heat is removed from the condenser either by a plant cooling tower water system, or outdoor air for remote condenser and outdoor air cooled chillers, or by plant air for portable or indoor heat reclaim chillers.
The Refrigeration Cycle Step by Step
The refrigeration circuit is the most technical part of how a chiller works.The refrigeration cycle uses the principles of thermodynamics to efficiently move heat from one area to another. In the case of chillers, heat is taken from the fluid being chilled and transferred to the ambient air.
1.The Compressor
The refrigeration cycle begins with the compressor. The compressor takes low-pressure low-temperature refrigerant in gas form and compresses it into a high-pressure high-temperature gas.
2.The Condenser
This gas then flows through coils in the condenser. While in the condenser, air or water will flow over the coils and remove heat from the refrigerant. As the refrigerant loses heat it will begin to condense until all of the gas has condensed into a liquid.
3.The Expansion Valve
After leaving the condenser, the liquid goes through the expansion valve. The expansion valve restricts the flow of refrigerant. When the high-pressure liquid goes through the expansion valve it enters the evaporator.
4.The Evaporator
The evaporator is where the refrigerant starts evaporating back into a gas. When the refrigerant evaporates it gets very cold and absorbs a lot of heat. It is in the evaporator that the process fluid will interact with the cold refrigerant. Heat is removed from the fluid and transferred to the refrigerant. The refrigerant will then enter the compressor and the cycle begins again.
