Evaporator coil

An evaporator is a device in a process used to turn the liquid form of a chemical substance such as water into its gaseous-form/vapor. The liquid is evaporated, or vaporized, into a gas form of the targeted substance in that process.

One kind of evaporator is a kind of radiator coil used in a closed compressor driven circulation of a liquid coolant. That is called an air-conditioning system (A/C) or refrigeration system to allow a compressed cooling chemical, such as R-22 (Freon) or R-410A, to evaporate/vaporize from liquid to gas within the system while absorbing heat from the enclosed cooled area, for example a refrigerator or rooms indoors, in the process. This works in the closed A/C or refrigeration system with a condenser radiator coil that exchanges the heat from the coolant, such as into the ambient environment.

A different kind of evaporator can be used for heating and possibly boiling a product containing a liquid to cause the liquid to evaporate from the product.

The appropriate process can be used to remove water or other liquids from liquid based mixtures. The process of evaporation is widely used to concentrate liquid foods, such as soap or to make concentrated milk called "condensed milk" done by evaporating water from the milk. In the concentration process, the goal of evaporation is to vaporize most of the water from a solution which contains the desired product.

An evaporator/evaporative-process can be used for separating liquid chemicals as well as to salvage solvents.

In the case of desalination of sea water or in Zero Liquid Discharge plants, the reverse purpose applies; evaporation removes the desirable drinking water from the undesired solute/product, salt.

One of the most important applications of evaporation is in the food and beverage industry. Foods or beverages that need to last for a considerable amount of time or need to have certain consistency, like coffee, go through an evaporation step during processing.

In the pharmaceutical industry, the evaporation process is used to eliminate excess moisture, providing an easily handled product and improving product stability. Preservation of long-term activity or stabilization of enzymes in laboratories are greatly assisted by the evaporation process.

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Wikipedia