Characteristics of ethylene glycol and propylene glycol as antifreeze:
|Property||Ethylene Glycol||Propylene Glycol||Comments|
|Freeze point depression||more effective||less effective||More antifreeze is needed of propylene glycol to achieve the same freeze point|
|Heat transfer efficiency/capability||better||less||Ethylene glycol has superior heat transfer efficiency due to lower viscosity - but more fluid must be circulated to transfer the same amount of energy since Propylene glycol has higher specific heat.|
|Viscosity||lower||higher||Propylene glycol increases major head loss in the systems. Pumps head increased.|
|Chemical oxygen demand||low||higher|
|Biodegrading||degrades in 10 - 30 days||needs more than 20 - 30 days to degrade|
|Carcinogenic||no||no||A carcinogen is any substance or agent that promotes cancer|
|Toxic||High level of acute when taken orally, targets the kidneys||Lower level of acute||Ethylene glycol should never be used in any drinking water or food processing system|
|Skin irritant||low||low||Propylene glycol is used in small amounts in cosmetics|
Air Conditioning systems - heating, cooling and dehumidification of indoor air for thermal comfort.
Material properties of gases, fluids and solids - densities, specific heats, viscosities and more.
Freeze protecting of cooling systems - temperature rating vs. required amount of antifreeze.
Online calculator, figures and tables showing density and specific weight of ethylene, C2H4, at varying temperature and pressure - Imperial and SI Units.
Specific heat of Ethylene Gas - C2H4 - temperatures ranging 175 - 900 K.
Properties like freezing point, viscosity, specific gravity and specific heat of ethylene glycol based heat-transfer fluids, or brines.
Comparing antifreezes used in water based heat transfer fluids or brines.
Freezing points of propylene glycol based heat-transfer fluids suitable for the food processing industry.
Comparing properties like specific gravity, freezing points and viscosity for secondary coolants like calcium chloride, sodium chloride, ethylene glycol and propylene glycol.