The article describes the main types of technological schemes for working out the flooded strata of sand deposits using hydraulic shovel excavators. The analysis of scientific and technical literature describing the experience of using hydraulic shovel excavators in the open-pit mining, including pits for the extraction of construction sand, has been carried out. The proposed technological scheme is that the development of reserves of the flooded strata without preliminary water reduction is carried out by a hydraulic shovel excavator from under water by a downward digging with the storage of the extracted rock mass in bulk (for dewatering), placed in such a way that when working out the next mining bench width, it is located within the working area of the excavator for simultaneous processing of the next bench width and loading of dewatered sand from the pile. Calculations of the parameters of the operating platform and the excavator block of the proposed technological scheme for conducting open-pit mining were carried out. The dependence for determining the minimum length of the mining operations front of an excavator for drawing up a technological scheme of operation of a backhoe hydraulic excavator on working out the flooded strata with the pile formation for dewatering sand and its subsequent uploading from the pile by the same excavator is presented.
The main features of the development of Open-complex structure of carbonate rocks. The dependence for the determination of dozing on the domestic heap career, moving overburden on bestransportnoy scheme in goaf. Found that the optimum length of excavator block executed by one parking dragline at quarries carbonate rocks is achieved with the minimum total cost of doing the work of overburden and waste associated with the removal of the overburden.
Variants of technological schemes of aggregates production by open-cast mine with mobile crushing and grading units is described. The measures to improve safety in open-cast mining are offered, and also ways to increase productivity of open-cast mines by changing the technological schemes and reducing the number of movements of mobile crushing and screening units.
The work describes basic features of open pit development of complex structure carbon deposits. The rational length of excavator block for different models of dragline for backfill mining method was determined. The work also gives the dependence for determining the production front length for development of complex structure carbon deposits with the use of railway service for transportation of the extracted mineral.
This paper first of all examines the notion of an equilibrium price for a mineral cоmmodity market. It draws the conclusion that microeconomic theory alone cannot define such a price. It then recapitulates on the reasons for price fluctuations and shows that one can at least identify a floor price and a ceiling price when it proves impossible to identify an equilibrium price. To conclude, it proposes a method for price forecasting, based on a prior analysis of the relevant industrial structure involved.
