RSSAssessment of Susceptibility of Coal to Spontaneous Combustion in OKR
Václav Zubíček
Spontaneous combustion of coal mass represents a considerable health hazard of workers and endangering mining operations, which is often connected with a failure of coal mining and costs of endogenous fire suppression. Prompt recognition of spontaneous combustion plays a very important role in deep working coal seams prone to spontaneous combustion. The susceptibility of coal to a spontaneously combustible process is considered as a feature of coal mass that can be specified by a laboratory test. Since seventies of the last century in OKR methods according to the author Olpinski and the oxidation method under adiabatic conditions have already been used to verify the tendency of coal to spontaneous combustion. Later the method of pulse calorimetry and the CPT (Crossing Point Temperature) method were used for the OKR coal. Experimentally the method according to the author Veselovskij was verified. The presented paper describes the objective methods, their technical performance and criteria of assessment of susceptibility of coal to spontaneous combustion.
Finding Parameters Producing Gas Outputs from Closed Underground Using Mathematic Model
Magda Vrbová
For a number of reasons, for example – population safety, but also with reference to potential alternative energy sources we investigate possibility of gas exploitation from free space in abandoned mines. In order to asses the real gas reserves in this surroundings we can use many methods. The solution in this report is focused on the Ostrava-Karvina field (OKR), especially the Jaklovecky Mine locality.
Spontaneous Combustion of Coal and its Early Detection on OKR Mines
Pavla Guřanová
Occurrence of spontaneous combustion of coal in OKR (Ostrava-Karvina Coal Field) still represents current problems worthy of solution. In OKR mining operations it is necessary to minimize permanently a risk of endogenous fire and its consequences to which as well a potential risk of possible initiation of air-methane mixture belongs that could lead to serious consequences in the form of mine accident accompanied by losses of human lives. The valid mining legislation of the Czech Mining Office imposes to check carbon monoxide occurrence in the mine atmosphere. Tracking further indicator gases of spontaneous combustion is imposed in the OKR mines by Decision of the District Mining Office in Ostrava [1]. The aim of the decision is to minimize risks resulting from occurrence of spontaneous combustion in the OKR mines. Actual findings confirm importance of inspection of indicator gas occurrence in the mine atmosphere as well as complexity of temperature estimation of the centre of spontaneous combustion. The presented paper deals with spontaneous combustion process, occurrence of spontaneous combustion of coal in OKR mines, some findings in the area of early detection of coal by indicator gases, it gives reasons for actual reserves in the given area and consider possibilities of improvement of temperature estimation of spontaneous combustion.
Utilization of LCI Analysis for Comparison of Energy Flows in Processes Using Biomass for Energetic Purposes with Classic Energetic Processes
Christina Serafínová
This article outlines a possible methodology of LCI analysis utilization for comparison of processes utilizing biomass for energetic purposes, e.g. energy crop and a concrete biomass waste with selected classic energetic processes, e.g. burning of black coal. Comparison of these processes is done on the level of energy flows of given processes and energy net yields from these processes.
Possibilities and Utilization of Software System for Coal Seam Economical Thickness Delimitation
Jiří Ardielli
The article deals with possibilities of utilization of the designed and developed BilPol software system that extremely facilitates, accelerates and specifies the very important initial stage of estimation of coal reserves. The system quickly and transparently compiles and illustrates logs of boreholes and cuttings with indicated seams and benches. In the user-friendly and intuitive graphic environment it provides the user tools for automated search and definition of economical seam parts. In the logs there are indicated in addition segments fulfilling some important criteria - e.g. maximum average content of ash as a qualitative parameter of usability conditions. The user application processes data of a coal database containing specifications of layers in boreholes and represents it graphically in a transparent form. The database has been conceived to be generally applicable on all coal deposits in CR. Using the BilPol system it is possible to compile more quickly and more precisely variant 3D models of balance and sub-economical parts of seams for subsequent calculation of coal resources. The system is implemented using the Microsoft Visual Basic language. While creating the program the additional component Microsoft Common Dialog Control 6.0 has been used for creation of the user environment [4]. Access to the database in the MDB format is provided through the Microsoft DAO 3.6 Object Library.
Interspecific Variations of Bark´S Water Storage Capacity of Chosen Types of Trees and the Dependance on Occurance of Epiphytic Mosses
Marie Valová , Silvia Bieleszová
Many studies show that the rates of water storage capacity can differ between different types of trees. The main purpose of this study was to compare specific water capacity of chosen types of woody species (Acer pseudoplatanus, Betula pendula, Carpinus betulus, Malus sp. as the representatives of broadleaved trees and as the representatives of coniferous were chosen species Larix decidua, Picea abies, Pinus sylvestris). In some cases the rates of water retention capacity between the chosen trees were considerable, e.g. the water retention capacity of Malus sp with the tree trunk perimeter of 100 cm was 0,886 g/cm3 and water storage capacity of pendula with a tree trunk perimeter of 100 cm was 0,342 g/cm3. There were big differences between the losses of moisture during a 24-hour period. The understanding of differences in interspecific variation of water retention capacity can help us to gain a better insight into occurrence of some organisms living on tree trunks and their dependence.
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Morphotectonic Analysis of Digital Relief Model – A Suitable Means of Searching for Zones of Rock Mass Brittle Failure
Jan Jelínek
The paper deals with the suitability of using the morphostructural analysis of the digital relief model (DRM) for compiling a geological map fault network focused on brittle failure of the rock mass. Attention is paid to the description of the procedure of interpreting the individual outputs of the morphometric methods selected. An important role in compiling the resulting network of the rock mass brittle fault failure is played by the comparative analysis of the structural-tectonic mapping with the morpholineament network obtained by morphostructural DRM interpretation. Unless the comparative analysis has been completed, the resulting morpholineament network can hardly be considered a fault network of the studied area. Many relief morpholineaments have no geological foundation. Finally, the resulting geological network is compared with the current geological maps and a brief summary is given on the advantages or disadvantages of the morphostructural analysis applied at compiling the fault network of the mass brittle failure. The selected area of interest was the Moravosilesian zone of the Bohemian Massif, which is exceptional for the superposition of three structural levels (Alpine, Variscan and Cadomian).
Modelling of The Dubňany Lignite Seam Base in The Moravian Central Depression (The Czech Part of The Vienna Basin)
František Staněk, Jan Jelínek, Josef Honěk, Kerstin Hoňková
This paper deals with the methodology of modelling the Dubňany lignite seam base and its tectonic failure. Tectonic pattern of the Vienna Basin has been subject of many studies. Opinions on its origin have been developing. Coal seams in the South Moravian Lignite Coalfield were modelled under the project of the example modern evaluation of the coal deposit. Designed software with application of modern mathematical, statistical and geostatistical methods and SURFER program were used for coal seam modelling. Input data were taken from detailed mining, deposit and well exploration carried out for more than 50 years.
Assessment of Indicator Gases of Spontaneous Combustion in Underground Mines in The Czech Republic
Alois Adamus
Research and applications of findings in the area of early indication of spontaneous combustion of coal using indicator gases started in the Czech Republic in the seventies to eighties of the last century. A significant progress occurred in the second half of the eighties, when methods of assessment of coal self-heating temperature were published in the Czech Republic (CR), e.g. in [1]. Consequently the objective findings of the research were projected in the year 1990 to generally binding legislation of the State Mining Authority of CR, imposing to track and assess indicator gases [2]. The matter of fact required to establish in the Ostrava-Karvina Coalfield (OKR) operational chromatograph laboratories covering requirements of practice. Further research was focused on improvement of assessment of self-heating temperature using indicator gases. The presented paper describes briefly the previous work experience and some findings of the research from the area of the tracking of indicator gases of spontaneous combustion in underground coal mines in CR.
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The Knowledge of Wood Gas Purification by Adsorption Cartridge Filters Follow Up with Its Application In Combustion Engines
Erika Sujová
The article deals with a highly actual theme of wood biomass exploitation for energy purposes, specifically problems of wood gas production and purification systems in relation to the requirements of combustion engines. Wood matter gasification represents one of the ways of alternative exploitation of wood matter in power engineering. The paper deals with filter efficiency and effectiveness evaluation by means of adsorption cartridge filters. The evaluation was carried out on a basis of determination of the ingoing and outgoing change of solid particles concentration in wood gas during a continuous 4 - hours loading. The evaluating criterion was an acceptable value of contaminants in wood gas for its utilization in combustion engines.
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Prevention Mechanism of Explosive of Air-Methane Mixture by Salt Inhibitors
Stanislav A. Kalyakin, Oleg Moroz
The most perspective direction of increasing the protecting property level of explosives is the usage of new chemically active inhibitor salts in their mixtures. However, we have no adequately clear understanding of the mechanism of the inhibition reactions taking place in air-methane mixtures under the explosion of an explosive charge. That’s why the identification of this mechanism is a problem that is of great scientific and practical importance.
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The Critical Conditions of Initiating Air-Methane Mixture Explosion with an Open Charge
Stanislav A. Kalyakin, Oleg Moroz
The investigation findings presented enable to determine the critical conditions of air-methane mixture (AMM) explosion initiation with an open charge in the test gallery. The findings enable to define the level of blasting safety in coal mines liable to gas explosions.
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Modelling of Gas Communications with Application to Abandoned Ida Mine in Ostrava-Karvina Coalfield
Magda Vrbová
Protection of building objects regarding a possible gas escape from closed mine excavations to the surface is a problem we can see in OKR very often. To prevent successfully gas emission it is necessary to specify a methodical procedure of this risk solution. Implementing such procedure is increasingly needful especially considering reducing mining in OKR and thus uncontrolled gas emission from these areas. At first, we need to determine the value of residual gases emission. According to this value we then determine the manner of enclosure. Two possibilities are introduced in the paper. We can use either the way, in which the gas will be taking away from settlement by means of boreholes or better by methane drainage pipeline. The better possibility is leaving the drainage pipeline in the shaft before filling, through which we can take away the residual coal gas capacity.
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Using Untraditional Sorbents for Sorption of Certain Heavy Metals from Waste Water
Miroslav Kyncl, Henrieta Pavolová, Katarína Kyseľová
The environment incl. water is exposed to heavy metals in the long term. Typically, industrial activities are the source of heavy metals penetrating the environment. The heavy metals are contained in many products and are a part of many waste substances. This paper deals with removal of copper, zinc and lead from waste waters by means of adsorption. Adsorbents are typically cheap substances, such as synthetic zeolite, bentonite or slovakite. Attention is paid to the adsorption rate and efficiency of removal of the heavy metals mentioned from the water.
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Assessment of Failure Condition of the Extracted Seams of the Firm Roof in Dependence on the Rock Mass Character
Eva Jiránková
As a result of the deposit caving, the original stress balance of the rock mass is affected; therefore, the stress always increases around the mined-out workings. The stress increase results in the stope surroundings compression distinguished by a certain surface subsidence measurable (the surface also features substantially smaller horizontal shifts as the second vector component of the general movement towards the mined-out workings metacentre). Determination of this subsidence value in relation to the extent and thickness of the mined-out workings is important to recognize the conditions under which a complete failure of the firm overlying layers occurred. At the first extraction in the area, that means failure in the whole thickness of overlying carboniferous rocks.
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Opportunities for Water Treatment Sludge Re-use
Miroslav Kyncl
This paper deals with the sludge that is produced within the treatment of water and production of drinking water. When alumina and iron coagulants are used for coagulation and clarification of surface water, mainly alumina and iron sludge are produced. This paper describes possible alumina recovery in the water treatment procedure and re-use of sludge for treatment of municipal wastewater. The sludge can be also used for production of cement. All those actions decrease the quantity of wastes and contribute to environmental protection. The waste sludge can be also used as secondary raw materials.
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Design and Realization of Set-Up For SPR Measuring Method
Adam Talik, Michal Lesňák, Ondřej Vlašín, Jaromír Pištora
Given paper describes modification of Gaertner L119 ellipsometer to apply the surface plasmon resonance (SPR) method. Final implementation has been tested on several basic measurements and obtained experimental data were compared with theoretical model.
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Contribution to Determination of Coal Grindability Using Hardgrove Method
František Tichánek
The paper deals with determination of grindability of coal using Hardgrove method. Some non-availabilities of determination are mentioned as well as factors affecting grindability and relations for conversion of Hardgrove Grindability Index (HGI) values to Bond Work Index (Wi). Paper also provides information on utilization of Hardgrove method in Czech Republic and indicates HGI values for coal from OKD-Karvina region.
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Resources of Utilization of Groundwater for Heat Pump in Košice - Slovakia
Ladislav Tometz
At present, there is an increasing interest denoted to utilisation of alternative energy sources. It is expressed especially in the municipal and/or industrial sphere, where energetic sources based on fossil fuels, are step by step eliminated by their different alternatives. A common groundwater, which is utilised in heat pumps for heating of objects, is one of the low-temperature energy sources. Košice is the second largest town in Slovakia and there is a large number of buildings with different pretensions to energy in them. From the hydrogeological point of view, the town of Košice is situated very properly and it seems that there is a sufficient amount of high-quality groundwater present, suitable for the above mentioned purposes. The submitted paper gives an overview of its utilisation.
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A Case Study in Uniform Conditioning of Local Recoverable Reserves Estimation for Jelšava Magnesite Deposit – Level 220
Ladislav Vizi
A practical case study for estimation of magnesite grade in Jelšava deposit in Slovakia is presented. The studied part of the deposit is a new level 220, vertically extended to the level 323, presently being exploited. Based on exploratory data analysis, the distributions of studied variables were modelled using Gaussian anamorphosis and transformed into normal distribution. The structural analysis and consequential variography was made for transformed variables in 3D space, resulted in a complex structural model of the spatial variability. Following the structural model, the average grades were simulated for the projected selective mining units (SMU) 16x16x6 m (panels). For recoverable reserves estimation purposes, the raw variables were transformed into Gaussian space for SMU volume as well as discretizating blocks 4x4x6 m inside each SMU. The results of the previous simulations and the change of support models were used for recoverable reserves estimation by uniform conditioning for series of different cut-offs.