Possibilities for the use of chemicals materials alternative to chlorides for decreasing road slipperiness in winter

Abstract

Having assessed in various aspects the study materials (salts), used for road maintenance in a cold period of the year, and taking a special consideration of the impact of these materials (salts) on the environment as well as their price, it could be stated that the most acceptable alternative for Lithuania is the already used sodium and calcium chloride salts. A large disadvantage of two materials (sodium chloride and calcium chloride) is that chloride ions strongly increase the speed of corrosion reactions of metals. Larger concentrations of chlorides aggravate vegetation processes and, thus, cause damage to roadside plants. Having assessed all the materials (salts) according to their chemical and physical properties and also according to their price and availability from technological point of view in the production, at present the following compounds could be distinguished: carbamide and calcium magnesium nitrates. When using calcium nitrate fewer chlorides get into the environment and the environment is less corrosive in regard to metals, however, here another problem occurs. If too large concentrations get into the environment, nitrates can cause pollution of ground water and soil. In future, having expanded the production of calcium and magnesium nitrates, it will be possible to start producing certain mixtures, e.g. carbamide with those nitrates or the mixture of carbamide, calcium, magnesium nitrates and calcium chloride, and, thus, to reduce a direct use of chlorides.