Making Roads Safer During A Winter Storm
If you live in one of the northern parts of the United States, you must have seen the snow and salt trucks that appear on the road even before a snowstorm begins. These trucks disperse salt on the roads before and during a snowstorm.
Salt is a common deicing agent used by cities to melt snow and ice on roads, sidewalks, and other surfaces. Salt melts snow and ice on roads because it can lower the freezing point of water, which helps to melt the snow and ice.
When you add salt to water, it dissolves and separates into ions. The ions in salt disrupt the bonds that hold water molecules together, lowering the water’s freezing point. As a result, the water will remain liquid at lower temperatures, which helps to melt the snow and ice.
The amount of salt needed to lower the freezing point of water depends on the concentration of the salt solution. The more salt added to the water, the lower the freezing point.
Salt is most effective at melting snow and ice when the temperature is above 20°F (-7°C). At colder temperatures, salt becomes less effective and may not melt the snow and ice effectively.
Salt is an effective and widely used method for melting snow and ice on roads, but it has drawbacks. Salt is corrosive and can damage concrete and metal. It can also have negative environmental impacts if we do not use it responsibly.
The Salt Used on The Roads
The most common type of salt used to melt snow and ice on roads is rock salt. We also know it as sodium chloride. Rock salt is an inexpensive and effective way to lower the freezing point of water. The lower freezing point helps to melt snow and ice on roads.
Rock salt is typically spread on roads using a salt truck or other specialized equipment. They spread salt thinly over the road surface and is typically most effective when the temperature is above 20°F (-7°C). At colder temperatures, rock salt becomes less effective and may not melt the snow and ice effectively.
Salts sometimes used to melt snow and ice on roads include calcium chloride, magnesium chloride, and potassium chloride. These types of salt are more expensive than rock salt, but they are more effective at lower temperatures. They can also be more environmentally friendly.
When temperatures are below 20°F (-7°C), rock salt (sodium chloride) becomes less effective at melting snow and ice. In these conditions, other types of deicing agents help melt the snow and ice.
Other Deicing Agents
One type of deicing agent that is effective at lower temperatures is calcium chloride. Calcium chloride can lower the freezing point of water to as low as -20°F (-29°C), making it more effective at melting snow and ice at very low temperatures. In addition, calcium chloride is less corrosive than rock salt and less harmful to the environment.
Another type of deicing agent that can be effective at lower temperatures is magnesium chloride. Like calcium chloride, magnesium chloride can lower the freezing point of water to very low temperatures and is less corrosive and environmentally harmful than rock salt.
Other deicing agents used at low temperatures include potassium chloride and urea. These deicing agents are less effective at lower temperatures than calcium chloride or magnesium chloride, but they can still be useful in certain situations.
The salt that cities use comes from underground deposits or harvested from seawater.
Rock salt, also known as sodium chloride, is the most common type they use for deicing. Rock salt is typically comes from underground deposits in various parts of the world, including the United States, Canada, Europe, and Asia.
Seawater can also be a source of salt for deicing. Again, it is because seawater contains dissolved salt, which can be harvested through solar evaporation. Seawater is collected in large ponds and evaporated in the sun, leaving behind dissolved salt.
Costs To Keep The Roads Safer
The cost of salt for deicing roads and sidewalks can vary depending on several factors, including the type of salt, the amount of salt needed, and the location.
Rock salt, also known as sodium chloride, is the most common type of salt used for deicing, and it is generally the least expensive option. The cost of rock salt can vary depending on the location and the supplier, but it is typically available for around $50 to $100 per ton.
Other deicing agents, such as calcium chloride and magnesium chloride, are more expensive than rock salt. Still, they are more effective at lower temperatures and can be less corrosive and environmentally harmful. These deicing agents can range from $100 to $200 per ton. Sometimes it could be more, depending on the supplier and location.
The cost of salt for deicing will depend on the specific needs of a city or organization. The expenses also depend on the availability and cost of salt in a particular region. Cities may also consider environmental and logistical factors when sourcing salt for deicings, such as the impact of mining on the environment or the cost of transportation.