As part of a pooled-fund research project, the Washington State Department of Transportation was selected to field test approximately 100 tons of calcium magnesium acetate (CMA) to evaluate its potential as a deicing chemical in direct comparison with salt (sodium chloride) and urea. Evaluation included all aspects of storage, handling, use, and performance. CMA was applied whenever necessary at each test site; the same application rates were used as those now used for salt. Typical equipment consisted of front dump trucks with the spinner ahead of the rear axle and rear-discharge hopper trucks. All equipment was used without modification.
The use of CMA at the beginning of a storm reduced the amount of bonding of snow to the roadway surface. This effect of keeping the roadway surface bare for longer periods of time reduced the cost of snow fighting. This was accomplished with a chemical application rate of 125 lb per lane mile.
The addition of sand to CMA reduced the problems of dust, caking, and uneven distribution. The sand provided moisture and weight to the application, which resulted in a smoother, more even distribution. CMA spread above the ice and snow was excessively dusty, which created problems in the spreading and distribution. CMA is slower to react on compact snow and ice than is salt or urea. This delay in reaction time was not considered a handicap in the overall snow-fighting procedure.
The conclusion was that CMA shows promise as a deicing-melting chemical. The problems of dust, light weight, and brittleness need further research and may be significantly alleviated by development of a hydrated compound.
Washington (State). Dept. of Transportation.
Alternatives analysis, Calcium magnesium acetate, Costs, Deicers (Equipment), Deicing chemicals, Dust control, Field tests, Handling and storage, Handling characteristics, Performance, Sand, Sodium chloride, Urea, Winter maintenance.