Industrial Coolants and Its Uses
Coolant is a substance that comes in liquid or gas form and used in regulating or reducing temperature of the system. The ideal coolant is something that has low viscosity, low-cost, chemically inert, non toxic, has high thermal capacity and neither promotes nor cause corrosion of cooling system. As a matter of fact, few applications for such need it to be good electrical insulator too.
While coolant is typically referred to HVAC and automotive applications, the industrial coolant is much more of a technical as it’s found in heat transfer fluid frequently used for low as well as high temperature for the manufacturing applications. At the same time, the term is used to cover cutting fluids. As for the coolants, it can actually stay on its phase, gaseous or liquid and at times, it undergoes a transition with latent heat which then adds the cooling efficiency. Now say for example that the latter is put into use to achieve below ambient temperature, then it is known as refrigerant.
A common type of coolant in the market is air. There are a couple of ways to which air cooling is used and it’s through passive cooling or also known as convective airflow as well as forced circulation by making use of fans. Hydrogen is being used as well for high performance gaseous coolant. Because thermal conductivity is higher in comparison to other gases, it is expected to have low density and high specific heat density allowing it to have low viscosity which many rotary machines are taking advantage of due to its vulnerability to windage loss. Currently, many big power plants are using hydrogen cooled turbo generators in their electrical generator.
The inert gases are being used as coolants for gas cooled nuclear reactors. 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. Sulfur hexafluoride on the other hand is being used for cooling and insulating high voltage power systems similar to 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. It becomes ideal for heat transfer medium given the fact that it has high heat capacity plus, it is cost effective. Most of the time, technicians are combining it with additives like antifreeze as well as corrosion inhibitors. In most cases, diethylene glycol, propylene glycol or ethylene glycol mixed in water is the components of antifreeze. A similar coolant is betain but with an exception that it’s manufactured using pure plant juice. The pure de-ionized water is utilized to cool electrical equipment because of its low electrical conductivity.