What are liquid deicers? 

A liquid deicer is basically a dry deicer that has been dissolved in water.

Whenever we dissolve a deicer in water, we are diluting it, and when we dilute the deicer we are also diluting its ice melting power. This gets us into an area of frequent misunderstanding and confusion.  The way deicers work is by lowering the freezing point of water.   

The science behind liquid deicers

The freezing point of brine changes as it gains more and more calcium chloride content. The minimum freezing point that we get in liquid calcium chloride is a concentration of 30%. That is what we call the eutectic.  The eutectic is the composition of a brine that has the lowest freezing point.  People often think if brine is at the lowest freezing point at the 30% calcium chloride, that must be the concentration I want to use to get the most ice melting power. 

We ran some tests measuring the ice melting capacity of liquid calcium chloride at different calcium chloride concentrations.  The amount of ice melting that we get at 30% calcium chloride, at that eutectic value, is not the highest amount of ice melting.  In fact, the highest amount of ice melting is with the brine that has the highest content of calcium chloride. As we progressively dilute the calcium chloride, we steadily lose ice melting capacity. 

Why on earth would we ever want to use a liquid deicer? 

The answer is increased efficiency. We pay a price by losing a little bit of ice melting capacity, but what we gain is the ability to apply that chemical in a more efficient way and lower our overall application rates. It turns out that liquids are a very good medium to distribute and apply deicing products. It allows us to reduce our overall application rates. This is important because it allows us both to minimize our costs and to minimize our environmental impact, because the goal is always use as little product as possible to get the job done.