
Calcium Chloride
By depressing the freezing point of water, calcium chloride is used to prevent ice formation and is used to de-ice. This application consumes the greatest amount of calcium chloride. Calcium chloride is relatively harmless to plants and soil. As a deicing agent, it is much more effective at lower temperatures than sodium chloride. When distributed for this use, it usually takes the form of small, white spheres a few millimeters in diameter, called prills. Solutions of calcium chloride can prevent freezing at temperatures as low as 52°C (62°F), making it ideal for filling agricultural implement tires as a liquid ballast, aiding traction in cold climates.It is also used in domestic and industrial chemical air dehumidifiers
The second largest application of calcium chloride exploits hygroscopic properties and the tackiness of its hydrates. Calcium chloride is highly hygroscopic and its hydration is an exothermic reaction. A concentrated solution keeps a liquid layer on the surface of dirt roads, which suppresses the formation of dust. It keeps the finer dust particles on the road, providing a cushioning layer. If these are allowed to blow away, the large aggregate begins to shift around and the road breaks down. Using calcium chloride reduces the need for grading by as much as 50% and the need for fill-in materials as much as 80%