Heat exchangers are aptly named for transferring heat from one medium to another. The mediums used in this exchange can be either liquid or gaseous, but must be of two different temperatures. The structure of a heat exchanger allows the two mediums to come in close contact, cooling one and warming the other. These two mediums may be separated by some sort of wall, or they may be touching completely.
The two fluids or gases involved in a heat exchanger may be held in separate chambers with a wall between them, but it’s not the most efficient arrangement. In order to get the maximum amount of contact between the two mediums, most heat exchangers are simply pipes that twist back and forth and wind within each other or it may be a winding pipe within a single chamber of one material. A heated material will flow through one pipe while a cooled material runs through the opposite pipe. As they come in close contact, the materials will heat or cool one other until they share an equal temperature. In other words, they exchange levels of heat.
What are Heat Exchangers Used For?
Heat exchangers can be used in several situations. Basically, a heat exchanger can be used anywhere one material needs to be warmed and another needs to be cooled. They don’t have to be any specific material, just that one will be warmed and the other cooled. Some examples of where heat exchangers are used are:
- space heating
- air conditioning
- power plants
- petroleum refineries
- natural gas processing
- sewage treatment
Heat exchangers are quite useful for industrial uses and, in some cases, the coolant is replaced with some chemical or fluid that needs to be warmed up anyway to save energy and materials. When used for absorption refrigerators, their purpose is to condense gaseous chemicals into liquid. At waste water treatment plants, a heated material is ran through one pipe to keep the anaerobic digesters warm in the other pipe, otherwise the digesters wouldn’t be able to break down waste properly.
All in all, heat exchangers do exactly what they sound like they do: they exchange levels of heat between two mediums. Heat exchangers help one material cool and another heat up for whatever reason such a process is needed.