On determining the parameters of face blocks during mining operations with backhoes

The backhoe hydraulic shovels (backhoes) have been widely used in open-pit mining operations in the Kuznetsk coal basin since the early 2000s. Now their number is growing every year, both because new operations begin on new sites, and because of the backhoe advantages. However, up to now parameters of their operation, more particularly the parameters of the face blocks, are often taken according to the actual data, i.e. based on the accumulated experience of the mining companies, and are not calculated using the approved scientifically validated methods. In the given article the authors give some preconditions for creation of a uniform methodology to calculate parameters of the face blocks depending on mining-geological and miningtechnical conditions. It is noted that the manufacturers of excavation equipment quote the data corresponding to the maximum possible parameters of the equipment operation, in particular the height of the excavated layer, as a result of which it is rather difficult to apply this in practice. Preliminary conclusions about the need to take into account the diversity of the above conditions and their interrelation with the parameters of a particular model of the excavation and loading equipment have been made.

Thermophilic Chloroflexi Dominate in the Microbial Community Associated with Coal-Fire Gas Vents in the Kuznetsk Coal Basin, Russia

Thermal ecosystems associated with areas of underground burning coal seams are rare and poorly understood in comparison with geothermal objects. We studied the microbial communities associated with gas vents from the coal-fire in the mining wastes in the Kemerovo region of the Russian Federation. The temperature of the ground heated by the hot coal gases and steam coming out to the surface was 58 °C. Analysis of the composition of microbial communities revealed the dominance of Ktedonobacteria (the phylum Chloroflexi), known to be capable of oxidizing hydrogen and carbon monoxide. Thermophilic hydrogenotrophic Firmicutes constituted a minor part of the community. Among the well-known thermophiles, members of the phyla Aquificae, Deinococcus-Thermus and Bacteroidetes were also found. In the upper ground layer, Acidobacteria, Verrucomicrobia, Actinobacteria, Planctomycetes, as well as Proteobacteria of the alpha and gamma classes, typical of soils, were detected; their relative abundancies decreased with depth. The phylum Verrucomicrobia was dominated by Candidatus Udaeobacter, aerobic heterotrophs capable of generating energy through the oxidation of hydrogen present in the atmosphere in trace amounts. Archaea made up a small part of the communities and were represented by thermophilic ammonium-oxidizers. Overall, the community was dominated by bacteria, whose cultivated relatives are able to obtain energy through the oxidation of the main components of coal gases, hydrogen and carbon monoxide, under aerobic conditions.

Permeability of Coking Coals and Patterns of Its Change in Leninsky Area, Kuznetsk Coal Basin, Russia

A prediction of the permeability of gas-bearing coking coals in the Leninsky area, Kuznetsk coal basin (Kuzbass), which is promising for the production of coal methane, was performed. The results of laboratory studies of coal permeability and cleat compressibility under hydrostatic stress conditions are presented. As the confining pressure increased by 8 times (from 1 MPa to 8 MPa), the coal permeability perpendicular to the butt cleat direction decreased by 6.7 times (from 60 mD to 9 mD). The coal cleat compressibility was 0.085 MPa−1. On the basis of the results of filtration tests and microstructural analysis of the coking coals, we provide the estimation of the permeability anisotropy along the bedding planes (perpendicular to the face and butt cleat directions). The predicted dependences of gas-bearing coking coal permeability perpendicular to the butt and face cleat directions on depth and on features of coal seam bedding were determined under uniaxial strain conditions. It was found that in the coking coal depth intervals, as the depth increased, their permeability decreased by 61–82%. The obtained results can be used to select facilities and to design industrial works for the extraction of coal methane in the region.

Nikolai Andreevich Chinakal: a Personality in Science Resume

The unique personality and scientific biography of Nikolai Andreevich Chinakal (1888–1979), a scientist in the field of mining, a Corresponding Member of the USSR Academy of Sciences make it relevant. He was the oldest among the members of the SB RAS and got his education before the October Revolution. He lived through change of epoch, turmoil of revolutions and wars, forced labour in a “sharaga”, scientific advances, technical failures and creative breakthroughs. This feature of his biography actualizes the ways of transiting a specialist from one social reality to another, where the profession determines the model of behavior. This transition required significant efforts since it was sometimes complicated by the historical context. The aim of the research is to study the mentality of the actor in science whose professional activity dominated over other social life imperatives. Importantly, Chinakal’s work was connected with two geographic regions known for their major coal basins: the Donetsk Coal Basin, or Donbass, and Kuznetsk Coal Basin, or Kuzbass. The author highlights the characteristic features of these regions and shows how they affected the engineering and organizational decisions made by the scientist. The methodology and research methods are based on the theory of biography, activity-oriented aspect of the life of the history actor that depended strongly on his occupation, B. Latour’s actor-network theory, systematic approach to studying the natural character of causality and network connections of the “scientist-science-object” structure examined in this work. N. A. Chinakal was actively involved in starting academic science in Siberia. For 28 years, he was a director of the Institute of Mining in the West-Siberian Branch of the USSR Academy of Sciences, which later became part of the Siberian Branch of the USSR Academy of Sciences. The authority and academic status of the director were of great importance for the institute staff. Equally important was the stability provided by Chinakal’s leadership. In our time, stability is very much in demand, although there is an imbalance of stability and instability, which is felt by the staff of the Institute of Mining. Keywords: science in Siberia, mining, Institute of Mining Siberian Branch, Russian Academy of Sciences, Nikolai Andreevich Chinakal, personality in science

Residential Development in the Coal Mining Districts of the Kuznetsk Basin in 1930–1932

The article features the problem of residential development that migrant workers had to face in the mining districts of the Kuznetsk Basin during the first five-year plan. The author identified the causes of the housing crisis in the early 1930s that forced many independent miners to abandon mining enterprises. The paper describes the agenda taken by the central government authorities of Donbass and Kuzbass in order to provide miners with housing. It focuses on the types of housing in the Kuznetsk Coal Basin according to the method of production and building patterns, including communal houses. Prefabricated standard wooden constructions made it possible to build a lot of houses in a relatively short period of time. The main mistakes included a poor material base, limited workforce, and a shortage of building materials. As a result, the initial construction program was never fulfilled. The research focused on the residential development of the coal mining town of Prokopyevsk, its types of dwellings, the number of citizens involved in mining provided with state-owned housing, and the average housing space per capita. Thanks to the housing commissioned, the housing stock was significantly increased in the coal industry in general, and, more particularly, in the Kuzbassugol coal mining trust. The extensive residential development was not aimed at improving the living conditions of miners and their families but at binding migrants to their mines in order to meet the coal-mining program of the first five-year plans.

Mechanical strength of slag crushed stone generated at coal-fired thermal power plants

Introduction. Production waste is used in the construction industry worldwide as it helps to cover a considerable portion of the industry’s demand for building materials. Coarse-grained slag deposits (slag crushed stone and sand), formed in the slag washout zone, have more potential for application than other ash and slag mixtures (coarse ASM), but they need more research. Mechanical properties of the slag crushed stone (coarse-grained ASM), formed in the course of coal combustion at Kansk-Achinsk, Kuznetsk coal deposits (in boilers equipped with liquid and dry slag removal facilities) and the application of the slag crushed stone in roadbuilding are considered. Materials and methods. In the course of the research, the crushability and the deformation modulus of particular fractions of slag crushed stone samples (in dry and water-saturated conditions) taken from the dumps of Novosibirsk TPP-3 (that consumes the coal of the Kansk-Achinsk coal mining field) and from Novosibirsk TPP-2 and Seversk TPP (that consume the coal of the Kuznetsk coal mining field) were identified. To assess the factors influencing the mechanical strength of the slag crushed stone, ignition losses, the content of flaky and acicular particles, dust and clay particles and clay lumps was made. Results. The difference in the mechanical strength of samples having different genesis was identified. The graphs obtained in the course of testing were assessed and deformability characteristics were calculated (for materials having different fineness values). The factors influencing the mechanical strength of slag crushed stone were determined. Dependencies between deformation parameters and crushability of the slag crushed stone were obtained. Conclusions. Some mechanical and physical parameters of the slag crushed stone were identified; they were applied to outline potential areas of the slag crushed stone application in road building. The mathematical relationship needed to project the deformation modulus of the slag crushed stone was identified. This relationship will be used to design structures to be made of this material.

Using pillar-free mining technologies in gently dipping and self-ignitable coal seams

Gently dipping coal seams of the Kuznetsk Coal Basin are cut exclusively by longwalls with preliminary drivage of twin gate ways. At the same time, the source of self-ignition in mines is pillars of coal left in mined-out areas. Endogenous fire hazard grows with higher losses of loose coal in mined-out areas due to a persistent increase in mining depth and in size of longwalls. This research aims at development of an alternative mining technology for gently dipping coal seams to reduce the risk of initiation of self-ignition sources in mined-out areas and at the determination of parameters of the technology elements as functions of coal seam thickness and mining depth. A new concept of preparatory works and actual mining in selfignitable coal seams is described. The study results obtained with numerical modeling of the stress-state behavior of rock mass and the developed technology elements at different stages of longwalling are presented. The studies show that endogenous fire hazard is reduced by means of extraction of coal pillar on the same line with face and due to elimination of aerological connection between the operating longwall and earlier mined-out area owing to construction of a separation belt made of solidifying materials between them. The cross-effect of the widths of the solidifying material belt and coal pillar as the elements of the developed technology is estimated.