N. V. Chersky Institute of Mining of the North, Siberian Branch of RAS (Yakutsk, Russia):

Zakharov E. V., Senior Researcher, Candidate of Engineering Sciences, zaharoff@igds.ysn.ru

The ability to control the properties of rocks and rock masses is critical for the northern regions, where negative temperatures may cause drastic changes in dispersed and hard rocks. These effects, however, may also be put to practical use through a variety of approaches. This article presents the results of long-term studies of the effects of negative temperatures on specific energy consumption when crushing rocks and coals of various deposits in Yakutia. A method has been developed for establishing specific energy consumption that allows assessing the effects of negative temperatures and freezing conditions on the energy intensity of rock crushing. It has been experimentally established that, in the temperature range from –5 to –15 °С, specific energy consumption values for crushing certain rocks and coals can be 5–50 % lower than they are at positive temperatures. In other words, certain rocks have a local minimum of reduction energy intensity. The respective energy intensity drop appears so significant that it must be taken into account in the engineering and design work in order to avoid severe accidents, for example, when calculating the stability of mine workings and various mining facilities, especially near seismic zones, areas of blasting work and rock bursts, etc. On the other hand, the data obtained also indicate the possibility of using negative temperatures to soften the rocks and to develop new energy-saving mining and processing technologies.

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