scholarly journals Prospects for the use of modern technological solutions in the flat-lying coal seams development, taking into account the danger of the formation of the places of its spontaneous combustion

2021 ◽  
Vol 250 ◽  
pp. 534-541
Author(s):  
Vladimir Zubov ◽  
Dmitrii Golubev
Keyword(s):  
Spontaneous Combustion ◽  
Underground Mining ◽  
Fire Hazard ◽  
Coal Dust ◽  
Economic Losses ◽  
Coal Seams ◽  
Emergency Situations ◽  
Wide Range ◽  
Spontaneous Combustion Of Coal ◽  
The Impact

Spontaneous combustion of coal remains an important problem for coal mines, which can lead to an explosion of methane and coal dust. Accidents associated with spontaneous combustion of coal can cause significant economic losses to coal mining companies, as well as entail social damage – injuries and loss of life. Accidents are known at the Kuzbass mines, which occurred as a result of negligent attitude to the danger of spontaneous combustion of coal, the victims of which were dozens of people. The analysis of emergency situations associated with spontaneous combustion of coal shows that the existing wide range of means of preventing endogenous fires does not provide complete safety when working out coal seams prone to spontaneous combustion, therefore, spontaneous combustion places continue to occur in mines. The consequences that may arise as a result of a methane explosion initiated by a self-ignition place indicate the need to improve the used technologies. The purpose of the work is to determine the impact of modern technological solutions used in functioning mines during underground mining of flat-lying coal seams prone to spontaneous combustion, and to develop new solutions that reduce endogenous fire hazard. Conclusions on the influence of leaving coal pillars in the developed space, isolated air removal from the stoping face through the developed space, the length of the stoping face and the excavation pillar, and other factors on the danger of the formation of spontaneous combustion places are presented. Conclusions about the possibility of using modern technological solutions in future are also drawn.

scholarly journals Determination of the Parameters of Technological Schemes for the Development of Coal Seams Prone to Spontaneous Combustion using Computer Simulation

2019 ◽  
Vol 105 ◽  
pp. 01016
Author(s):  
Sergey Meshkov
Keyword(s):  
Computer Simulation ◽  
Spontaneous Combustion ◽  
Longwall Mining ◽  
Underground Mining ◽  
Fire Hazard ◽  
Modern Technology ◽  
Coal Seams ◽  
Mining Operations ◽  
Gas Dynamic ◽  
Mining Coal

The study considers thr problem of endogenous fire hazard in underground mining of coal seams prone to spontaneous combustion. The main trends in the development of modern technology of underground coal mining are shown. The interaction of air-gas-dynamic and geomechanical processes in the development of coal seams by longwall mining is considered. The possibilities of computer simulation of air-gas-dynamic processes in the extraction districts of modern coal mines are considered. The significant influence of geological and mining conditions of mining operations on the distribution of air flow in extraction districts and the efficiency of gas emission control in the workings of the extraction districts are shown. The design scheme and the results of numerical studies (methane and oxygen concentration fields) are given. It is concluded that it is necessary to determine the rational parameters of the preparation, ventilation, isolated drainage and degassing schemes when developing gas-bearing coal seams that are prone to spontaneous combustion. Recommendations are given on improvement of the safety in mining coal seams that are prone to spontaneous combustion.

scholarly journals Ozone damage, detoxification and the role of isoprenoids – new impetus for integrated models

2016 ◽  
Vol 43 (4) ◽  
pp. 324 ◽  
Author(s):  
Supriya Tiwari ◽  
Rüdiger Grote ◽  
Galina Churkina ◽  
Tim Butler
Keyword(s):  
Stomatal Conductance ◽  
Environmental Conditions ◽  
Economic Losses ◽  
Plant Responses ◽  
Damage Scenarios ◽  
Biochemical Processes ◽  
Wide Range ◽  
Defence Responses ◽  
High Concentrations ◽  
The Impact

High concentrations of ozone (O3) can have significant impacts on the health and productivity of agricultural and forest ecosystems, leading to significant economic losses. In order to estimate this impact under a wide range of environmental conditions, the mechanisms of O3 impacts on physiological and biochemical processes have been intensively investigated. This includes the impact on stomatal conductance, the formation of reactive oxygen species and their effects on enzymes and membranes, as well as several induced and constitutive defence responses. This review summarises these processes, discusses their importance for O3 damage scenarios and assesses to which degree this knowledge is currently used in ecosystem models which are applied for impact analyses. We found that even in highly sophisticated models, feedbacks affecting regulation, detoxification capacity and vulnerability are generally not considered. This implies that O3 inflicted alterations in carbon and water balances cannot be sufficiently well described to cover immediate plant responses under changing environmental conditions. Therefore, we suggest conceptual models that link the depicted feedbacks to available process-based descriptions of stomatal conductance, photosynthesis and isoprenoid formation, particularly the linkage to isoprenoid models opens up new options for describing biosphere-atmosphere interactions.

scholarly journals Peculiarities of using classification indicators of the coal metamorphism degree for predicting the hazardous coal seams properties

2020 ◽  
Vol 201 ◽  
pp. 01014
Author(s):  
Mykola Antoshchenko ◽  
Elvira Filatieva ◽  
Vladyslav Yefimtsev ◽  
Vadym Tarasov
Keyword(s):  
Spontaneous Combustion ◽  
Chemical Activity ◽  
Mining Engineering ◽  
Coal Seams ◽  
Mining Operations ◽  
Emergency Situations ◽  
Specific Composition ◽  
Geological Conditions ◽  
Definition Of ◽  
Mining Coal

Currently, there is no reliable regulatory framework for determining the hazardous properties of coal seams, including the propensity of coal for spontaneous combustion. Under relatively identical mining engineering and geological conditions for mining coal seams, the probability of emergency situations is determined to a large extent by the genetic properties of coal. The research methodology is based on the classical definition of metamorphism, which characterizes the change in the composition and properties of coal. The analysis involves indicators that directly or indirectly characterize the elemental composition of organic and mineral mass, chemical activity and physico-mechanical properties. This will allow to establish a specific composition and properties that contribute to the manifestation of certain hazardous properties of coal seams during mining operations. It is shown that the modern industrial classification does not take into account the change in the organic and mineral constituents of coal, which does not make it possible to use it unchanged to predict the hazardous properties of coal seams.

On determining coal classification indicators for establishing dangerous properties of mines

2020 ◽  
pp. 149-159
Author(s):  
М. Antoshchenko ◽  
◽  
V. Tarasov ◽  
R. Zaika ◽  
O. Zolotarova ◽  
...  
Keyword(s):  
Thermal Decomposition ◽  
Organic Matter ◽  
Fire Hazard ◽  
Coal Dust ◽  
Gas Content ◽  
Technological Parameters ◽  
Coal Seams ◽  
Volatile Substances ◽  
Main Indicator ◽  
Seam Mining

Currently, more than 20 qualification indicators are known by which degree of metamorphic coal transformations are established. Most of these indicators are designed for determining technological properties with industrial use of coal in mind. Due to sufficient knowledge of the indicators used, industrial classifications are constantly being improved. The modern classification by genetic and technological parameters groups the coals by the grades based on ten indicators. Of these, only one - the mass yield of volatile substances during the thermal decomposition of coal - is used as the main indicator of the manifestation of dangerous properties of coal seams without due scientific justification. Dangerous properties of coal seams during mining include: gas content of coal, a tendency to gas-dynamic phenomena and spontaneous combustion, dust forming ability and explosiveness of coal dust. In industrial classifications, the main indicator is determined for the dry ash-free state of organic matter. Manifestation of dangerous properties of coal seams occurs in the presence of both moisture and mineral impurities. This fact is not taken into account by other auxiliary indicators used to predict the hazardous properties of coal seams. Moisture in coal seams is in at least four states, and it is completely removed while analyzing the samples and is not taken into account in volatile products of thermal decomposition of coal. Thus, when using the indicator of mass output of volatile substances, influence of moisture in any form of its presence in coal on the occurrence of emergency situations is automatically ignored. The probability of emergencies during mining is largely determined by the ratio between components of organic mass (C, O, H, S, N) and mineral impurities. It is also not taken into account in normative documents which regulate safety of coal seam mining. The classification indicators defined in different ways characterize different aspects of coal conversion in metamorphic processes. Volatiles yield and average vitrine reflectance, well studied in industrial applications, correspond to different aspects of degree of conversion of starting organic matter. In order to establish dangerous properties of coal seams, their mutual substitution is unacceptable, which is confirmed by nonlinear connection between them. The existence of a genetic relationship between the outburst and fire hazard of coal seams has been established. This indicates the need to develop a unified classification of the hazardous properties of coal seams by genetic, mining engineering and geological parameters. The scientifically substantiated use in regulatory documents of a set of classification indicators that directly characterize the manifestations of the hazardous properties of coal seams will help to reduce number of accidents and injuries in coal mines.

scholarly journals Metamorphism Indicators for Establishing the Endogenic Fire Hazard of Coal Mining Plants in Mining

2021 ◽  
Vol 12 (8) ◽  
pp. 242-248
Author(s):  
V. Tarasov ◽  
◽  
M. Antoshchenko ◽  
Ye. Rudniev ◽  
O. Zolotarova ◽  
...  
Keyword(s):  
Organic Matter ◽  
Carbon Content ◽  
Coal Mining ◽  
Oxygen Content ◽  
Entire Range ◽  
Spontaneous Combustion ◽  
Fire Hazard ◽  
Small Degree ◽  
Wide Range ◽  
Main Components

In coal mining, the problem of particular importance is the occurrence of endogenous fires and explosions of the methane-air mixture, which lead to the death of people. The aim of the study is to establish indicators that directly characterize the change in the elemental composition in the process of metamorphic transformations of coals and determine them tendency to spontaneous combustion. Statistical multivariate analysis showed that the degree of metamorphism is the most significant characteristic of the propensity of coal to oxidize. The sum of the content of the main components decreases inversely to the increase in carbon content over the entire range of coal conversion from a small degree of their metamorphism from coal to anthracites. The dependence of decrease in oxygen content with increased carbon is nonlinear. With carbon content of more than 88%, there is a slight decrease in the rate of oxygen reduction in comparison to its decrease at earlier stages of metamorphism. A significant correlation of carbon with oxygen and hydrogen is observed. A characteristic feature of coals containing up to 75% carbon is a wide range of changes in formation moisture and oxygen content in organic matter. It indicates minor transformations of coals at the early stages of metamorphism. One of the signs of an increase in the influence of metamorphic processes is a one-sided increase in the carbon content in organic matter and a functional decrease in the sum of the remaining components - hydrogen, nitrogen, sulfur and oxygen.

scholarly journals An Intelligent IoT Based People Evacuation Guidance Model for Fire Hazard

2020 ◽  
Vol 8 (6) ◽  
pp. 4238-4242
Keyword(s):  
Large Scale ◽  
Fire Hazard ◽  
Personal Digital Assistant ◽  
Economic Losses ◽  
Shopping Malls ◽  
Public Buildings ◽  
The People ◽  
Wide Range ◽  
Fire Smoke ◽  
Guidance Model

With the development of science and technology, the design of modern architecture is becoming more and more attractive. The large-scale public buildings such as shopping malls, office buildings, Research centres and education centres are increasing dramatically. In case of sudden disasters and the overloaded electricity may easily cause fire and the fire smoke, fire in large buildings spread over a wide range of areas and produces physical damages, several hazard to life and property and atmospheric pollution. This paper proposes An Intelligent IOT based People Evacuation Guidance Model for Fire Hazard to guide the people by constructing the evacuation path dynamically based on the real time situation to reach the safety exit quickly in large public buildings using their Personal Digital Assistant like mobile phone, tabs etc. Whenever a fire breaks out, IOT module alerts the people to find the safety exit. Thus, the proposed system minimizes danger and economic losses by guiding the optimized evacuation path. The performance of the proposed system will be compared with the existing system and the result of improvement will be shown.

scholarly journals Research on a Gas Index Reflecting the Sorption Process on Carbon Materials in Coal Mines

2018 ◽  
Vol 10 (7) ◽  
pp. 2468 ◽  
Author(s):  
Karolina Wojtacha-Rychter ◽  
Adam Smoliński
Keyword(s):  
Carbon Materials ◽  
Spontaneous Combustion ◽  
Coal Mines ◽  
Sorption Process ◽  
Quantitative Relation ◽  
Gas Mixture ◽  
Coal Seams ◽  
Mine Fire ◽  
Sorption Column ◽  
Spontaneous Combustion Of Coal

Based on the concentration of gases such as propylene and ethylene in the atmosphere of a mine, it is possible to assess the development of a mine fire. With the increase of coal temperature, an increased emission of these gases has been observed. However, the experiment results presented in this paper prove that the use of propylene and ethylene for the prediction of the spontaneous combustion of coal have some limitations. It was found that during a flow of gas mixture through the sorption column, propylene and ethylene were sorbed on coal. This phenomenon manifests in smaller amounts of gases at the outlet of the sorption column. By comparing the concentration of ethylene to propylene at the inlet of the column, it was concluded that the ratio was usually below 3, whereas the range of the ratio at the end of the column was between 0.6–353. The value of gases ratio changed depending on the type of coal material in the column. The results of this experiment provide useful information that the quantitative relation between ethylene and propylene concentrations may indicate the occurrence of the sorption process on carbon materials in coal seams.

scholarly journals Grapevine Trunk Diseases: A Review of Fifteen Years of Trials for Their Control with Chemicals and Biocontrol Agents

Plant Disease ◽  
2018 ◽  
Vol 102 (7) ◽  
pp. 1189-1217 ◽  
Author(s):  
Vincenzo Mondello ◽  
Aurélie Songy ◽  
Enrico Battiston ◽  
Catia Pinto ◽  
Cindy Coppin ◽  
...  
Keyword(s):  
Biocontrol Agents ◽  
Economic Losses ◽  
Active Ingredients ◽  
Grapevine Trunk Diseases ◽  
Eutypa Dieback ◽  
Wide Range ◽  
Efficient Control ◽  
Botryosphaeria Dieback ◽  
Trunk Diseases ◽  
The Impact

Grapevine trunk diseases (GTDs) represent one of the most important problems for viticulture worldwide. Beyond the original causes of this outbreak in some countries like France, the lack of efficient control protocols and the prohibition of using active ingredients such as sodium arsenite and benzimidazoles, until recently used to reduce the impact of some GTDs but deleterious for humans and the environment, have probably worsened the impact of the diseases, leading to increasing economic losses. Since 1990, searches have been made to find efficient tools to control GTDs, testing a wide range of active ingredients and biocontrol agents. This review provides readers with an overview of the results reported in the scientific literature over the last 15 years. In particular, the review focuses on the trials carried out applying chemicals or microorganisms to control Esca complex diseases, Botryosphaeria dieback, and Eutypa dieback, the most widespread GTDs.

scholarly journals The Impact of the Ventilation System on the Methane Release Hazard and Spontaneous Combustion of Coal in the Area of Exploitation—A Case Study

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4891
Author(s):  
Magdalena Tutak ◽  
Jarosław Brodny ◽  
Dawid Szurgacz ◽  
Leszek Sobik ◽  
Sergey Zhironkin
Keyword(s):  
Spontaneous Combustion ◽  
Ventilation System ◽  
Hard Coal ◽  
Oxidation Reactions ◽  
Usual Practice ◽  
Methane Release ◽  
Effective Operation ◽  
Spontaneous Combustion Of Coal ◽  
The Impact

Various types of natural hazards are inextricably linked to the process of underground hard coal mining. Ventilation hazards—methane and spontaneous combustion of coal—are the most dangerous; they pose a major threat to the safety of the workers and decrease the effectiveness of the whole coal production process. One of the methods designed to limit the consequences of such hazards is based on the selection of a ventilation system that will be suitable for the given mining area. The article presents a case study of an active longwall area, where—due to increasing ventilation hazard (methane and spontaneous combusting of coal)—the whole system was rebuilt. The U-type ventilation system was used in the initial stage of the extraction process, however, it often generated methane in amounts that exceeded the allowable values. Consequently, such conditions forced the change of the ventilation system from a U–type to Y–type system. The new system was installed during the ongoing mining process, unlike the usual practice. The article presents the results of tests on mine gas concentrations and descriptive statistics for both types of ventilation system. The results clearly demonstrate that the U-type longwall ventilation system, in the case of high methane release hazard, prevents safe and effective operation. At the same time, the use of this system limits the carbon oxidation reactions in the goaf, leading to spontaneous heating and combustion, which is confirmed by the low concentrations of gases—by-products of these reactions. In turn, the use of the Y-type longwall ventilation system ensures safe and effective operation in areas with high methane release hazard, but at the same time deteriorates the safety associated with the spontaneous combusting of coal. The presented case—both from a scientific and practical perspective—is quite interesting and greatly broadens the knowledge in the scope of an efficient ventilation system for underground workings.

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