Methodological principles of an on-site statistical point estimation of the particle-size distribution of a rock mass

1982 ◽  
Vol 16 (7) ◽  
pp. 420-426
Author(s):  
V. A. Kuznetsov
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Point Estimation ◽  
Statistical Point ◽  
Methodological Principles

scholarly journals INFLUENCE OF PARAMETERS OF EXPLOSIVE DESTRUCTION OF MINING BLOCKS OF COMPLEX GEOLOGICAL STRUCTURE ON THE PREPARATION OF THE MINING MASS FOR PROCESSING

2018 ◽  
pp. 68-74
Author(s):  
К.V. Babii
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Iron Ore ◽  
Geological Structure ◽  
Contact Zones ◽  
Complex Geological Structure ◽  
A Charge ◽  
Explosive Destruction

Purpose: to investigate the influence of the parameters of explosive destruction of mining blocks of complex geological structure on the production processes of mining and processing of iron ore. Determine the stability of the escarpment slopes during excavation of rocks in ore mining blocks with barren layers. Results. The analysis of geophysical methods for studying the structure of deposits. It is proposed to use the magnetic susceptibility method for well logging. The structure of mining blocks of a complex geological structure with contact zones "ore - host rocks" was investigated. It has been proven that for the effective use of equipment for the pre-enrichment of ore in a quarry there are conditions: the regulation of the granulometric composition of the rock mass and the reduction of ore splices with overburden rocks. It is proposed to use a charge design of an explosive with inert gaps or a charge section of a cumulative action in the explosive destruction of rocks with contact zones. The influence of parameters of explosive destruction of mining blocks of complex geological structure on the formation of technological complexes of ore beneficiation in quarries is established. The dependence of the factor of stability of slopes of slopes during excavation of rocks, depending on the geological parameters. Scientific novelty. The regularities of changes in the parameters of the ore mass flow (medium piece and oversize) are established depending on the diameter of the drilling-blast wells, which allows you to adjust the particle size distribution. Practical significance. Based on the established patterns and improvement of the design of well charges, their influence on the quality of the blown-up rock mass in the ledges of a complex geological structure has been substantiated, which makes it possible to form the corresponding technological complexes of ore dressing in quarries. The result is a significant increase in the productivity of the technological equipment of the mining enterprise and the profitability of iron ore mining. Key words: quarry, ledge, complex geological structure, downhole charge structures, particle size distribution.

scholarly journals Particle Size Distribution of Cemented Rockfill Effects on Strata Stability in Filling Mining

Minerals ◽  
2018 ◽  
Vol 8 (9) ◽  
pp. 407 ◽  
Author(s):  
Jiangyu Wu ◽  
Meimei Feng ◽  
Jingmin Xu ◽  
Peitao Qiu ◽  
Yiming Wang ◽  
...  
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Particle Size Distribution ◽  
Coal Seam ◽  
Size Distribution ◽  
Longwall Mining ◽  
Poisson Ratio ◽  
Triaxial Compression ◽  
Friction Angle ◽  
Economic Benefits

It is of great significance for engineering safety, economic benefits, environmental protection, and sustainable development to investigate the strata stability in filling mining with cemented rockfill. Consequently, this paper is based on a specific coal mine where we applied the fully-mechanized longwall mining and filling and designed a cemented rockfill material for which the particles satisfied the Talbot gradation. Uniaxial and triaxial compression experiments were carried out on the cemented rockfill specimen, which obtained the relations between the mechanical parameters (Poisson ratio, elastic modulus, compressive strength, cohesive force, internal friction angle, and tensile strength) and the particle size distribution of the aggregate. The excavation and filling processes in the coal seam were simulated based on the numerical software FLAC3D. The characteristics of the displacement and stress fields of the strata when the goaf was filled by cemented rockfill with different granule gradations were discussed. The influences of the particle size distribution and mining distance on the maximum subsidence displacement of the coal seam roof, internal stress of the backfill, and the stress of the rock mass in the coalface were analyzed. The feasibility and effectiveness of the filling mining with cemented rockfill to protect the integrity of the overlying strata were discussed. The results showed that optimizing the particle size distribution of the aggregate in cemented rockfill could increase the loading capacity of the backfill to improve the filling effect, effectively control the strata movement, and decrease the stress of rock mass in the coalface to reduce the potential danger.

Justification of parameters and technology of drilling and blasting operations to ensure the required lumpiness

2021 ◽  
pp. 110-115
Author(s):  
V.V. Egorov ◽  
A.N. Volokitin ◽  
N.V. Ugolnikov ◽  
A.V. Sokolovsky
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Design Stage ◽  
Production Cycle ◽  
Lump Size ◽  
Optimal Technology ◽  
Average Size ◽  
The Cost

The practice of mining and blasting operations both during the development of a mineral deposits, and at the mine design stage, often involves the question of selecting the technology options and operation parameters. Virtually all recommendations for selecting the best production option are based on minimizing the total costs for the entire technological cycle of mining activities. In most cases the optimal technology and parameters of mining and blasting operations depend on the commercial, maximum permissible and average size of the blasted rock mass, which are determined by the type and capacity of the mining haulage equipment. Therefore, the total costs will mainly depend on the commercial or average lump size and the cost of mining transport equipment. The article presents a methodology to select the best technological option for the drilling and blasting operations to obtain the optimal lumpiness (particle-size distribution) of the blasted rock. The optimal range of lumpiness is defined by the total minimum costs for the entire production cycle of mining and processing of minerals. In order to select a rational technology of drilling and blasting and to calculate their parameters it is proposed to take into account the integral criteria of lumpiness in addition to the average lump size. For this purpose, we studied the particle size distribution in the rock mass and in the muck piles.

scholarly journals New Theoretical and Methodological Approaches to the Study of Heat Transfer in Coal Dust Combustion

Energies ◽  
2019 ◽  
Vol 12 (1) ◽  
pp. 136
Author(s):  
Evgeniy Toropov ◽  
Konstantin Osintsev ◽  
Sergei Aliukov
Keyword(s):  
Heat Transfer ◽  
Mathematical Model ◽  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Coal Dust ◽  
Thermal Characteristics ◽  
Combustion Chambers ◽  
Methodological Approaches ◽  
Methodological Principles

The existing theories of heat transfer in combustion chambers of boiler units fail to take into account a number of important factors that affect the reliability of results, and the methodological approaches to optimizing combustion processes can be revised in view of the spatial and temporal parameters of flame. Hence, the research aimed to improve the fundamental theoretical and methodological principles of studying heat transfer in coal dust combustion in the combustion chambers of industrial steam generators. The authors proposed to extend the theory of heat transfer with the mathematical description of particle size distribution of coal dust. In addition, the authors used the developed mathematical model of coal dust combustion based on a continuous curve of the particle size distribution in the ensemble. The mathematical model is consistent with the aeromechanical and thermal characteristics of flame. This work introduced a concept of flame continuum as a continuous medium, where the processes of combustion and heat transfer are studied. To achieve the research aim, in this paper, the methods of combustion chamber zoning, the equations of stationary and non-stationary heat conduction, radiation, and convective heat transfer, were used. These methods were tested on a number of high-temperature units.

METHODOLOGICAL PRINCIPLES OF MEASURING GRANULOMETRIC COMPOSITION

2020 ◽  
Vol 3 (1) ◽  
pp. 112-123
Author(s):  
Y.I. VINOGRADOV ◽  
◽  
S.V. KHOKHLOV ◽  
A.V. BAZHENOVA ◽  
S.T. SOKOLOV ◽  
...  
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Size Distribution ◽  
Granulometric Composition ◽  
Particle Size Analysis ◽  
Size Analysis ◽  
Methodological Principles

The article describes the methodological principles of measuring fragments size distribution for rock mass, to determine the content by weight of various fractions and the studied material in justification number, intervals and sizes of pieces. The principles of selection and processing of data for particle size analysis are determined.

scholarly journals Rational crushing of mineral raw materials by well charges as a factor of environmental safety of blasting works in quarries

2021 ◽  
Vol 64 ◽  
pp. 138-153
Author(s):  
V Kolesnik ◽  
A Pavlychenko ◽  
T Kholodenko ◽  
A Kirichenko
Keyword(s):  
Particle Size ◽  
Rock Mass ◽  
Particle Size Distribution ◽  
Size Distribution ◽  
Construction Materials ◽  
Environmental Safety ◽  
Shock Adiabats ◽  
Rock Destruction ◽  
Dust Emissions

Purpose. Improving the environmental safety of blasting operations in quarries for the extraction of non-metallic and construction materials based on their rational explosive crushing, aimed at reducing the effect of overgrinding, accompanied by the formation of fine fractions of materials and significant dust emissions. The research methodology provided a theoretical analysis of the destruction processes of a rock massif by well charges of explosives on the basis of calculations of shock adiabats of an explosive wave in rocks at different speeds of detonation of explosives. Experimental verification of the identified patterns was performed by assessing the quality of blasting by the particle size distribution of the rock in the collapse. Research results. The scientific and practical task of ensuring rational explosive crushing of materials in quarries with the use of elongated borehole charges has been solved. Mechanisms for the destruction of rock massifs and the peculiarities of the distribution of destruction zones by dispersed composition have been established, which contributes to the reduction of dust emissions into the atmosphere to an acceptable level of environmental safety of blasting operations in quarries. Comparative estimates of the shock load during the explosion of the explosive charge for the main rocks at different levels of the rate of detonation of charges are given. The dependence of the volume of overgrinding rock in the zone of its adjacency to the charge on the detonation velocity of explosives has been established. An experimental verification of the identified patterns in the current quarry by assessing the quality of blasting by the particle size distribution of rock mass in its collapse after experimental explosions with different parameters is done. Scientific novelty. The multiphase process of rock destruction by explosion was investigated by the calculated determination of the parameters of the shock adiabats of the blast wave in different rocks and at different detonation velocities of explosives. It is shown that during the destruction of a rock mass by the explosion of an elongated borehole charge of explosives, several specific zones of destruction are formed, the characteristics of which differ in particle size distribution. The area of controlled crushing is highlighted, where the intensity of rock destruction can be changed by adjusting the parameters of the explosive load and the area of little or almost unregulated crushing. The possibility of managing the process of dust formation and, accordingly, the level of environmental safety of blasting works in quarries for the extraction of non-metallic and construction materials is substantiated. Practical meaning. The identified patterns and provisions to reduce the effect of mineral overgrinding were used in the development of measures to improve the environmental safety of blasting in the quarry, which, in particular, provided an increase in well spacing in the range up to 3.0-3.4 m and reduce specific energy consumption from 1.27 g/cm3 to 0.97 g/cm3.

Effects of Particle Size Distribution on Corrosion Rate of Carbon Steel in Soil

2020 ◽  
Vol 69 (4) ◽  
pp. 102-106
Author(s):  
Shota Ohki ◽  
Shingo Mineta ◽  
Mamoru Mizunuma ◽  
Soichi Oka ◽  
Masayuki Tsuda
Keyword(s):  
Particle Size ◽  
Carbon Steel ◽  
Corrosion Rate ◽  
Particle Size Distribution ◽  
Size Distribution

DENSE SPRAY CORRECTIONS FOR DIFFRACTION-BASED PARTICLE SIZE DISTRIBUTION MEASUREMENTS

1995 ◽  
Vol 5 (1) ◽  
pp. 75-87 ◽  
Author(s):  
Christine M. Woodall ◽  
James E. Peters ◽  
Richard O. Buckius
Keyword(s):  
Particle Size ◽  
Particle Size Distribution ◽  
Size Distribution
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