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Abstract
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Laboratory melting tests were conducted to determine the amount of ice melted by dosages of sodium chloride, calcium chloride in both flake and pellet form, and mixtures of sodium and calcium chloride.
RESULTS show that: (1) the quantity of melting was independent of the ice thickness, (2) the amount of melting varied directly with the quantity of the added salt, (3) the amount of melting varied with the amount of calcium chloride in sodium-calcium chloride mixtures, (4) the amount of melting in a given time was greater at higher temperatures, and (5) with calcium chloride the rate of melting was initially rapid with a subsequent slow-down, and with sodium chloride the rate was initially slow with a later speed-up, so that a time might be reached where the rate with sodium chloride equalled or became greater than that with calcium chloride. The exact comparison was dependent on the temperature. Laboratory tests including measurements of a combined melting and breakage of bond between ice and slabs, and a test incorporating the added action of a revolving wheel were used. Test results show that the results with mixtures of sodium and calcium chloride are practically always intermediate between those for tests with the straight salts. It is considered that the wheel test most nearly approached field conditions. |