Cooling towers are an essential element in the vast majority of industrial processes. These mechanisms are used as heat rejection devices.
They get rid of waste heat and push it into the atmosphere by cooling a water stream to a lower temperature than before. Cooling towers are crucial to moderating the temperature of working fluids and can be applied in a number of different ways.
Additionally, two main methods are used to cool these water streams. Many cooling towers and chilling systems utilize the process of evaporation to lower heat levels and cool fluids.
Others tend to rely simply on the air as a means of cooling the fluid. These mechanisms have many common applications in the world of contemporary engineering.
Heating, Ventilation, and Air Conditioning Cooling Towers
A popular way to classify cooling towers is by use. These devices, which are abbreviated HVAC cooling towers, are used to reject the unwanted heat from a chiller.
Chillers can be cooled either by air or by water, while the water-cooled devices are known to carry out a more energy-efficient process.
These cooling towers are usually quite small in size compared to industrial cooling towers. Buildings such as schools and large offices tend to use one or more of these cooling mechanisms in areas that contain a particularly hot climate.
Industrial Cooling Towers
Contrary to HVAC cooling towers, industrial cooling towers are mainly used to get rid of heat from sources like machinery. The primary function of these cooling mechanisms is to get rid of the heat that is taken in by circulating cooling water systems.
Such systems include petrochemical plants, petroleum refineries, natural gas processing plants, semiconductor plants, and many more.
Coal-fired power plant are typically prone to make use of industrial cooling towers. The usual circulation rate of cooling water in a 700 MW plant is about 315000 gallons/minute. The water that is circulating needs a supply water make-up rate of about 5 percent.
Methods of Heat Transfer
An important element of these cooling devices is the method by which they transfer heat. Three different methods are mainly used.
Dry cooling towers: These mechanisms work by transferring heat through a surface that keeps the air and functioning fluid separate from one another.
This can be done by means of a heat exchanger that uses the convective transfer of heat. No evaporation is involved in this process.
Wet cooling towers: Unlike the previously mentioned method, wet cooling towers carry out their function through evaporative cooling.
The evaporated fluid, usually water, is combined with the working fluid with no need for separation.
Fluid coolers: These devices are also known as closed circuit cooling towers.
By this process, the working fluid goes through a tube bundle. Clean water is then sprayed, and a draft occurs by means of a fan. The resulting process is a heat transfer that has properties of both wet cooling towers and dry cooling towers.
The working fluid is also kept safe from contamination that may have potentially stemmed from the outside environment.