Pre Wetting

Pre-Wetting Dry Deicers: The Secret Behind Effective Deicing

The use of a liquid to pre-wet dry chloride deicers and abrasives has been around for a lot longer than most people realize. Pioneered over 30 years ago, a study by Marquette University concluded that substantial savings in materials (30%) is recognized when pre wetting is employed.

What is Pre-Wetting?

Pre-wetting of salt is a process of coating, or treating, the dry material with a liquid. Generally done in the range of 8 to 12 gallons of liquid per ton of material, this approach has many benefits. Pre-wetted salt will stick to the pavement and becomes less prone to blowing off from traffic before it can begin to activate or brine. The type of liquid used to pre wet can be anything from a solution of salt brine to a high performance formulated product, such as our BioBrinetm, magnesium chloride, or calcium chloride liquid. These can be further enhanced with admixtures of products like Caliper and IceBan for corrosion inhibition.

More Information on Pre-wetting

THE STUDY in pre-wetting that changed it all:

http://www.trc.marquette.edu/publications/IceControl/ice-control-1992.pdf

A variety of choices are available to customers who want to try pre-wetting salt:

  • On board systems that spray the materials as they fall down the chute to the spinner on board each truck
  • Stationary systems that work like a shower treating the entire load as it is loaded
  • Stockpile treatment of salt as it is loaded into the storage shed

All of these approaches have pros and cons. Determining which one is best for you is where we can help.  At MeltSnow.com, we have been involved in specifying, building, and engineering pre wet systems for over 30 years.

How Much Liquid Should I Order for the Pre-Wetting Appliction?

At a minimum, sufficient storage tank capacity is needed to service your needs. A good rule of thumb is that you should be able to store at least 1.5 full tank trucks of liquid. The reason is simple: If you take deliveries of liquid that are less than 45,000 lbs, then you are paying to haul air in the tank truck. Our tankers hold approximately 4,500 gallons of liquid. Our costs to move that tanker from our facility to your facility are the same whether it has 4,500 gallons, or 450 gallons. The cost of the delivery will not change since you are paying to move the whole truck irrespective of how much product is in it.

The best economics are when we can deliver full tank truck quantities to our customers. That generally requires that the customer has sufficient storage to allow some “heel” in the tank to cover the time between when product is ordered and when it is delivered, normally a few days. On this basis, we try to recommend 6,000-gallon storage tanks for all of our liquid customers as a starting point. More to the point, if our costs of moving our tankers are $450 per delivery, then a delivery of 450 gallons costs $1.00 per gallon as compared with 4,500 gallons, which costs only $0.10/gallon — a savings of $0.90/gallon in freight costs alone! This is pretty significant when you consider that most of our liquids are priced at less than $0.50/gallon plus delivery costs.

What Sort of Equipment Will I Need for Pre-Wetting Applications?

Because of our experience in pre-wetting and the wide range of tanks, pumps, and controls we offer, we can openly discuss the needs of our customers and offer options that result in well designed, affordable equipment and a successful liquid pre-wetting program. And because we also supply storage and base dispensing equipment and direct liquid applicators of similar quality, we can work with you to implement an entire liquid winter maintenance program from concept to storm fighting.

Here’s a primer on the equipment, including truck mounted pre-wetting systems

Hopper Spreaders:

Saddle tanks are designed to fit in the triangular space on the sides of a spreader and to fit in a dump body if required. Tank sizes range from 20 gallon, for pick-up spreaders, to 150 gallon for tandem axle trucks.

Tailgate or Dual Purpose Spreaders:

Designed to fit on the tailgate of the truck, capacities range from 35 to 180 gallons.  Chassis mount tanks are designed to fit between the cab and dump body (clearance of 14” is required). Capacities range from 60 to 160 gallons.

Pumps:

Meltsnow.com has pumps powered hydraulically or by 12 volt electric that are enclosed in NEMA 4 rated, sealed fiberglass enclosures. Over the past 30 years, we have learned which components will give dependable service and are affordable.

Controls:

Meltsnow.com designs and manufactures control systems specifically for highway maintenance. Our controllers range from simple on/off models to sophisticated, solid state, data logging units. All are proven dependable and guaranteed for one year.

MeltSnow.com’s Quality Assurance:

Pre-wetting equipment is used in the worst imaginable conditions. Constantly exposed to vibration, abrasion, corrosion, and temperatures down to –40°F, the equipment must function dependably.