Rock Salt Makeover
By Bob Carter
Matt Rogers from U.S.based Commodity Weather Group LLC recently said that winter 2009-10 would be the coldest on record in the U.S. Northeast since 1982. According to Rogers, extreme cold conditions will persist over North America through the end of March. The culprit is the actual positioning of El Nino, which set up camp further to the West than expected and near the International Date Line. Prevailing wind patterns mean … we shiver.
Recently, an Ontario Provincial Police spokesperson made an on-air plea for safer driving on local highways since salt wasn’t working at recorded temperatures and wind chills near -20°C (-4°F). Since white salt fails to make a dent at or below -8°C (17°C), we must look at alternatives.
With colder temperatures, rising fuel costs and challenging economy that pretty much sucked every penny from our clients’ operating budgets, there is an undeniable need for greater application efficiencies. One such option is to pretreat salt.
Improved processes
A performance argument for adding premium liquids to white salt is not new. The brining process is fast-tracked, and the amount and placement of product can be controlled with pinpoint accuracy.
However, early forms of “pretreated” product experienced inconsistencies in the blending process, leading to leaching and uneven performance on the road. Today, leading manufacturers offer enhanced liquids, including magnesium chlorides, treated with agricultural additives, dyes and other materials to lower the effective operating temperatures of the finished goods.
With all the colors used to differentiate products and act as application markers on the market today, it would be possible to create a pallet rivaling the selection at your local paint store. But are all treated salts created equal, and why would they matter to contractors?
Today’s premium treated products can achieve longer-lasting performance at lower temperatures.
Today’s premium treated products can achieve longer-lasting performance at lower temperatures.
When blended properly with relatively dry salt, infusions of these enhanced liquids can be made up to 29-30 liters (approximately 8 gallons) and held as stable products. The finished hybrid product delivers a faster melt, longer-lasting residual effect and a greater operating temperature range compared with white salt.
Quality counts
When adding liquids, not just any liquid will do. Contractors must consider the quality of the liquid being used.
Magnesium chloride liquids perform to lower temperatures than simple salt brines. Additional agricultural enhancers such as molasses, beet juice, distillers’ by-products and corn sweeteners are often added to reach performance at even lower temperatures than those achieved by MgCl alone.
The reasons for the faster action, extended performance and longer-lasting results can be directly attributed to these agricultural additives. The presence of these de-sugared and sugar solids (depending on the source supply) add particulate matter and change the liquid’s molecular structure. This helps depress the freezing point of the liquids beyond that possible with lesser quality and cheaper salt brines and multi-chloride brines.
The added viscosity acts as a natural corrosion inhibitor, protecting metal surfaces on vehicles and application equipment. This extra viscosity helps create a stable blend free from liquid loss to leaching.
Cost savings
Experienced applicators now have a choice. Drivers working with premium treated products have commented that they save money by either applying less product or by requiring fewer applications when using the same amount of treated product as white salt on the first pass. The residual effects of premium treated salts yield bare roads and parking lots hours beyond that made possible with simple white salts. This can help buy time when product is applied at the beginning of the storm event, often avoiding the need for secondary applications.
Additional savings are realized as treated salts stay where they are placed and don’t exhibit the bounce and scatter that takes valuable product away from where it is needed most. It will be necessary to calibrate spreading equipment to make sure the tackiness of the treated product and the force of application deposits the product where it is needed most and not beyond. Pinpoint accuracy saves money.
Fewer passes mean lower operating costs including time on the road, wear and tear on equipment and fuel costs.
With crude oil prices expected to be at or above US $95 per barrel by the end of 2010, and with projected increases to all fuel types across the board, it makes sense to look for efficiencies wherever we can.
