Where are Industrial Coolants Used?
Coolant is that type of substance that is used for reducing or regulating the system’s temperature that comes in gas or liquid form. Few of the best coolants that can be used are those that are of high thermal capacity, non toxic, chemically inert, low cost, has low viscosity and neither causing or promoting corrosions to the cooling system. Some of its applications require the coolant to be electrical insulator as well.
When the term coolant is used, we often associate it to automotive as well as HVAC applications but industrial coolant is a lot different since it’s more of a technical aspect and used generally in low and high temperature manufacturing applications. The term is covering cutting fluids at the same time. Coolants might be able to stay on its phase, gaseous or liquid or it can even undergo a transition with latent heat that adds to the efficiency of cooling. Now say for example that the latter is put into use to achieve below ambient temperature, then it is known as refrigerant.
Air is a very common form of coolant in the market. Air cooling is making use of either forced circulation by using fans or convective airflow or otherwise known as passive cooling. Hydrogen is used too for high performance gaseous coolant. The thermal conductivity is a lot higher compared to all other gases, it has low density and high specific heat density and as a result, low viscosity which is actually a benefit for rotary machines that are vulnerable to windage losses. Currently, many big power plants are using hydrogen cooled turbo generators in their electrical generator.
As for nuclear reactors that are gas cooled, what is used in this purpose is inert gases. Helium basically has low tendency to absorb neutrons and for that, the odds of it becoming radioactive is less. Carbon dioxide is actually used to be mixed with AGR reactors and Magnox. In regards to sulfur hexafluoride however, this is utilized to insulate and even cool high voltage power systems; to give you examples, it can be switches, transformers, circuit breakers and so on. Steam can also be used where there is high specific heat capacity required in gaseous form.
A very common type of coolant is water. Its low cost as well as high heat capacity has made it ideal for heat transfer medium. Usually, it’s used with additives similar to antifreeze as well as corrosion inhibitors. Antifreeze solution is made out of suitable organic chemicals oftentimes diethylene glycol, propylene glycol or ethylene glycol in water. Betaine is of similar coolant with an exception that it’s made from pure plant juice and therefore hard to ecologically dispose or non toxic. The pure de-ionized water is utilized to cool electrical equipment because of its low electrical conductivity.