For comparison of environmental performance of rock mass hoists, methods of calculating the volume of harmful emissions into the environment and comparative assessment of their environmental characteristics and economic efficiency are developed. According to the results of calculations recommendations are given and estimated data on the operation of the most promising designs of hoists in deep quarries are given.
The effective operation of transport systems of deep pits requires a comprehensive assessment of their quality on the basis of economic, environmental and mining-technical factors. For this purpose, it is necessary to develop a mathematical model of functioning of transport systems, allowing to estimate in concrete operating conditions various types of open-pit elevators and to define interrelation between operational and ecological characteristics of transport system and conditions of their operation. The final task of the research is to substantiate the rational types of rock mass hoists and the area of their effective application.
The results of calculations of efficiency of application of the main methods of normalization of the atmosphere of the open pit are given. As an example, the conditions of open pit Udachny of AK Alrosa and the basic models of dump trucks with carrying capacity of 100-150 tons of domestic and foreign production are considered. The model and the developed medicine allow to substantiate the choice of optimal transport complex taking into account the dynamics of mining works, the environmental factor and various models of loading and transporting equipment.
The mining industry is dominated by road transport. The Vostochny mine, part of the Apatit enterprise, is no exception. The scientific and technical forecast shows that, despite the significant disadvantage inherent in this type of technological transport - atmospheric pollution by exhaust gases - there is no alternative to it in the rather distant future. The main ore reserves are concentrated and developed by the Koashva open pit. Transportation of ore from the pit face to the excavator transfer depot and of rock from the pit face to the dump is performed by dump trucks. In the project the open pit will reach a depth of 570 meters in a closed circuit. At such depth of mining the use of auto dump trucks BelAZ-7512 and BelAZ-7519, which are in operation now, becomes extremely unprofitable and power-consuming. One of the promising types of transport for deep pits is a vertical cage air cushion hoist. Such an elevator is a device for lifting auto-dump trucks to the side of the quarry and their descent into the quarry. The elevator is a vertical shaft with a platform moving on it under the action of air pressure from below. The value of overpressure is small and is provided by a standard mine ventilation system.
