Before that, winter Moscow was sprinkled with technical salt for seven years. She, as you know, corrodes not only car bodies, but also power lines. In 1998, with the filing of some deputies of the Moscow City Duma, the process began to reject the use of salt. But they planned to switch to modern chemical reagents gradually: they dragged on time to check the compositions - you never know how it will affect our roads … Finance also did not contribute to sudden movements: a ton of salt costs 400 rubles, and calcium chloride (the most popular reagent) - 1500. In addition, salt requires 320 thousand tons, and a new chemical - more than 500. And the equipment! We need special sprayers, car depots. As a result, ice liquefaction costs 10 billion rubles instead of two. Think about it!
By the way, the authorities also detached from another need - to conduct a detailed examination. We determined the effect of the reagent on soil and trees, and what effect it has on people (respiratory organs, skin), animals, concrete, asphalt, metal - no one thought to study. At that time there was no document with the results of the study of the adhesion of the wheel to the road treated with reagents, but at different temperatures. So we got the result - slippery film on the roads. As a result, motorists suffered.
Prior to the experiment, Mayor Luzhkov was asked not to completely give up salt. But most metropolitan officials were in favor of salt not being used at all. And the mayor himself was categorical: "There should not be salt!" And off we go, or rather it fell and poured onto our roads.
Everyone got scared, rushed to chemists and other ecologists. It turned out that the first failures were not to blame for the reagent, but communal workers who simply could not handle the trains. And we need, as always, accuracy and foresight, that is, respect for proportions and cooperation with Moshydromet. There is a forecast of frost, which means we pour liquid reagent. Once on the asphalt, it significantly lowers the freezing temperature of the water film. And the road surface remains wet, which, you see, is better than ice. But here it is important not to overdo it (see above). Excess fluid on the road is useless - tire grip will deteriorate.
The granular chemical must be strewed after the fact, that is, directly onto the snow and ice crust. Granules begin to actively melt ice and snow. The reagent works for several hours. Quickly seeping to the asphalt, it forms a brine, breaking the connection of ice with the road. And then it's up to cars or pedestrians who will turn all this into a mess.