Liquid chillers are essential to industries including medicine and medical supply, food and beverage, plastics manufacturing, HVAC, and power generation.
Applications
Industrial liquid chillers are used to cool machinery, mechanisms, and products used in a variety of processes. Examples of such processes include metalworking, die casting, plastic injection molding, welding, chemical processing and industrial refrigeration. Liquid chillers are also used to provide air conditioning and gas cooling on a large scale and provide temperature control for medicines and lab chemicals.
How They Work
Chillers utilize vapor-compression or absorption processes to carry out their cooling functions. Both of these processes use a refrigerant that absorbs heat from a predetermined place. As that refrigerant condenses, it evaporates and releases the heat in a different place. They also both may make use of cooling towers or vents to help them expedite the cooling process.
The majority of chillers work using a four-stage cycle: pressurization, condensation, depressurization, and evaporation. It occurs as described below.
Pressurization
Pressurization is part of the vapor-compression chilling process. It is not part of the absorption chilling process.
Condensation
During this stage, which is typically the start of absorption chilling, the chiller machine transfers the refrigerant into a condenser. The condenser features a set of coiling tubes with air or water circulating around it. Within the condenser, the refrigerant vapor cools and converts into a liquid.This part of the process removes a significant amount of heat. The heat then is absorbed by the water or air circulating around the tubes.
Depressurization
The newly refrigerated liquid moves to an expansion valve, where the liquid is depressurized. Expansion valves work by sensing both the actual and the target temperatures and responding with the appropriate amount of refrigerant.
Evaporation
Once depressurized, the liquid can begin to evaporate. Evaporation causes an extreme decrease in the liquid’s temperature. For this to happen, the chilled liquid moves into an evaporator or heat exchanger, which evaporates the liquid and absorbs the heat.