Wszystkie pola: coal seam - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Numerical simulation on mining effects of upper coal seam on lower coal seam of splitting area of splitting and merging coal seam
Symulacja numeryczna efektów wydobywania węgla w górnym pokładzie węgla na dolny pokład węgla na obszarze rozszczepienia w pokładzie o cechach rozszczepienia i scalania
Autorzy:: Zha, W. H.
Hua, X. Z.
Xiong, L. J.
Huang, R.
Powiązania:: https://bibliotekanauki.pl/articles/348696.pdf
Data publikacji:: 2012
Wydawca:: Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:: rozszczepienie i scalanie
naprężenia stropu
prawo pęknięć
symulacja numeryczna
splitting and merging
floor stress
failure law
numerical simulations
Opis:: The main mining coal seams 71 and 72 of Huaibei mine area show a relation between splitting and merging. Under the slicing mining circumstance of the splitting area, it is the key problem to face the mining area to ensure the safety of the lower 72 coal mining. Based on face 7225 of Xutuan Coal Mine the influence of 71 coal seam mining on the coal seam 72 was analyzed by the FLAC3D. The law of stress propagation in the floor, failure extent and movement during the mining of coal seam 71 and coal seam 72 were studied by the numerical simulation; it provides the basis for roof management and support selection of 72 coal seam mining.
Główne pokłady węglowe nr 71 i 72 kopalni Huaibei wykazują cechy zarówno rozszczepienia, jak i scalania. Podczas wybierania warstwowego na obszarze rozszczepienia głównym problemem jest zapewnienie bezpieczeństwa dolnego pokładu nr 72. Na przykładzie przodka 7225 kopalni Xutuan przeanalizowano wpływ wydobycia w pokładzie nr 71 na pokład nr 72 przy użyciu programu FLAC3D. Propagację fal naprężeń w spągu, zakres pęknięcia i przesunięcia podczas wybierania pokładu węgla nr 71 i 72 zbadano za pomocą symulacji numerycznej, co daje podstawy do lepszej kontroli stropu i do wyboru obudowy pod wybieranie pokładu węgla nr 72.
Źródło:: AGH Journal of Mining and Geoengineering; 2012, 36, 3; 471-479
1732-6702
Pojawia się w:: AGH Journal of Mining and Geoengineering
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 2.

Tytuł:: CO2-ECBM and CO2 sequestration in Polish coal seam – experimental study
Autorzy:: Baran, P.
Zarębska, K
Krzystolik, P
Hadro, J.
Nunn, A.
Powiązania:: https://bibliotekanauki.pl/articles/91967.pdf
Data publikacji:: 2014
Wydawca:: Główny Instytut Górnictwa
Tematy:: coal
sorption
sequestration
carbon dioxide
methane
ECBM
węgiel
sorpcja
sekwestracja
dwutlenek węgla
metan
Opis:: Purpose: Methane recovery is interesting not only because of its clean combustion; it is also beneficial for the environment because of the reduction of the amount of methane emitted into the atmosphere, which is important because of methane’s significant impact on the greenhouse effect. However, desorption of methane is a slow process, significantly dependent on the coalification of coal, its porosity and petrographic composition. Injection of carbon dioxide into the coal bed under sufficient pressure might be a factor in stimulating the efficiency of this process, as – because of preferential sorption – carbon dioxide displaces methane molecules previously absorbed in the coal matrix. Methods: The measurements were made for Polish low-rank coal used for the analysis of methane recovery from Polish coal mines. Coal samples were collected from sites used for geological, sorption and petrographic research, as well as for the assessment of the reservoir’s genetic origin CH4 content. Experimental studies of sorption were performed with the use of the volumetric method at a lower and higher gas pressure. Results: The methane isothermes show more than double the reduction of adsorption along with increasing temperature. The most sig-nificant changes of sorption capacity due to temperature variations can be seen when observing the difference in the course of the hysteresis of sorption/desorption of the gas as a function of temperature. In cases where there is a temperature of 323 K, a temperature hysteresis loop might indicate larger quantities of methane trapped in the porous structure of coal. In cases of carbon dioxide as sorbate, a similar shape of sorption isotherms occurred at both temperatures, while the temperature increase caused approximately double the reduction of sorption capacity. Also the isotherm’s shape is similar for both temperatures of measurement, indicating no effect of temperature on the amount of gas within the structure of the tested coal. High-pressure isotherms of CO2 and CH4 are confirmed in the literature, proving that carbon dioxide is the gas that allows the best penetration of the internal structure of bituminous coal. The critical temperature of CO2 (304.5 K) is so high, that sorption measurements can be performed at room temperatures (293, 298 K), where activated diffusion is relatively fast. Practical implications: Understanding the sorption of gases is the primary issue, related to the exploitation of coal seams, when explaining the mechanism of gas deposition in coal seams and its relationship with outbursts of rocks and gases in mines. Originality/ value: The results indicate successful sorption of carbon dioxide in each experiment. This provides the rationale to study the application of the coal tested to obtain methane genetic origin genetic methane with the use of the CO2 injection.
Źródło:: Journal of Sustainable Mining; 2014, 13, 2; 22-29
2300-1364
2300-3960
Pojawia się w:: Journal of Sustainable Mining
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 3.

Tytuł:: Case study: Mechanism and effect analysis of presplitting blasting in shallow extra-thick coal seam
Autorzy:: Sun, Qiang
Shan, Chegfang
Wu, Zhongya
Wang, Yunbo
Powiązania:: https://bibliotekanauki.pl/articles/2203332.pdf
Data publikacji:: 2022
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: pokłady węgla
wydobycie węgla
węgiel
szhallow-buried thick coal seam
hard roof and coal seam
fully mechanised top coal caving mining
blasting presplitting
parameter optimisation
Opis:: The caving effect of the top coal caving is crucial for efficient mining. Using the Yushuling coal mine, Xinjiang province, China, as a case study, the coal and rock physical and mechanical parameters, such as the compressive, tensile, and shear strength values and hardness of the top coal and roof rock, were determined. The analysis of the effect of different factors on the blasting presplitting process was numerically simulated, and the optimal parameters of blast drilling were identified. Three presplit boreholes were implemented: in the workface, the workface’s advance area, and the two roadway roofs in the workface’s advance area. The optimal blasting drilling parameters and charge structure were designed. The field test results in the mine under study indicated that the top coal recovery rate of the 110501 fully mechanised top coal caving face was improved twice (from 40 to more than 80%), and an effective blasting presplitting was achieved. The proposed blasting presplitting method has an important guiding significance for fully mechanised top coal caving mining in Xinjiang and similar mining areas.
Źródło:: Archives of Mining Sciences; 2022, 67, 3; 381--399
0860-7001
Pojawia się w:: Archives of Mining Sciences
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 4.

Tytuł:: In-situ coal seam and overburden permeability characterization combining downhole flow meter and temperature logs
Autorzy:: Busse, J.
Scheuermann, A.
Bringemeier, D.
Hossack, A.
Li, L.
Powiązania:: https://bibliotekanauki.pl/articles/1395710.pdf
Data publikacji:: 2016
Wydawca:: Uniwersytet Śląski. Wydział Nauk o Ziemi
Tematy:: coal seam detection
permeability
geophysical logging
exploration
methodology
przepuszczalność
pokłady węgla
metodyka
poszukiwania
Opis:: The planning and design of any coal mine development requires among others a thorough investigation of the geological, geotechnical and hydrogeological subsurface conditions. As part of a coal mine exploration program we conducted heat pulse vertical flow meter testing. The flow data were combined with absolute and differential temperature logging data to gain information about the hydraulic characteristics of two different coal seams and their over- and interburden. For the strata that were localised based on geophysical logging data including density, gamma ray and resistivity hydraulic properties were quantified. We demonstrate that the temperature log response complements the flow meter log response. A coupling of both methods is therefore recommended to get an insight into the hydraulic conditions in a coal seam and its overburden.
Źródło:: Contemporary Trends in Geoscience; 2016, 5, 1; 1-17
2299-8179
Pojawia się w:: Contemporary Trends in Geoscience
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 5.

Tytuł:: 4D gas geological research on coal seam with gas hazard potential in mining panel
Autorzy:: Cui, Hongqing
He, Xin
Wang, Zehua
Powiązania:: https://bibliotekanauki.pl/articles/2201387.pdf
Data publikacji:: 2022
Wydawca:: Główny Instytut Górnictwa
Tematy:: gas geology
gas hazard prevention
small geological structure
fine geological survey
4D analysis
geologia gazowa
zapobieganie zagrożeniom gazowym
mała struktura geologiczna
szczegółowe badania geologiczne
analiza 4D
Opis:: According to regulations of the mining industry in China, it is necessary to carry out gas hazard prevention projects in advance when mining coal seams with gas hazard potential, and gas geological research should be taken as the basic work for optimal design and effective construction of gas hazard prevention projects. Research on coal seam with gas hazard potential have shown that anomalous geological area could be the gas hazard potential area as well, where superimposed tectonic and mining stress field usually results in tectonically disturbed coal and pressured gas. A 4D gas geological research method is used to find out the anomalous geological area and assess its gas hazard potential. The method covers two ranges of gas geological research: fine geological survey and 4D analysis. The former includes a comprehensive prospect of concealed small geological anomalies (such as small fault, small fold and coal thickness variation) by use of gas extraction projects; The latter includes a dynamic forecast of gas hazard potential from space-time perspective based on numerical simulation analysis on additional stress fields around small geological structures beyond coal mining face. Its research benefit the optimal design and effective implementation of gas hazard prevention measures in coal mining panel with high coal and gas outburst potential.
Źródło:: Journal of Sustainable Mining; 2022, 21, 2; 112--119
2300-1364
2300-3960
Pojawia się w:: Journal of Sustainable Mining
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 6.

Tytuł:: Determination of stress state in coal seam based on inverse problem solution using acoustic sounding data
Autorzy:: Kudaibergenov, Mels K.
Iskakov, Kazizat T.
Kudaibergenova, Bakytzhan S.
Powiązania:: https://bibliotekanauki.pl/articles/88885.pdf
Data publikacji:: 2019
Wydawca:: Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:: coal seam
stress
elasticity theory
biharmonic equation
inverse problem
Opis:: The paper presents an algorithm for calculating the horizontal, vertical and tangential stresses in a horizontal coal seam lying between galleries. These stresses are expressed in terms of the Airy function, which satisfies a homogeneous biharmonic equation. For its numerical solution it is necessary to set boundary conditions. Practical limitations do not allow us to determine the tangential stresses on horizontal boundaries of the coal seam. Calculations of stresses are proposed to be carried out in two steps. The first step is to solve the inverse problem for the biharmonic equation to find unknown tangential stresses on horizontal boundaries of the coal seam. The inverse problem is solved by minimizing the residual functional. Its strong convexity is proved, which implies the existence and uniqueness of the solution of the inverse problem. The second step is to solve the boundary value problem for the biharmonic equation to calculate stresses in the coal seam. The result of a numerical experiment is presented.
Źródło:: Mining Science; 2019, 26; 173-187
2300-9586
2353-5423
Pojawia się w:: Mining Science
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 7.

Tytuł:: Phosphorus minerals in tonstein; coal seam 405 at Sośnica-Makoszowy coal mine, Upper Silesia, southern Poland
Autorzy:: Kokowska-Pawłowska, M.
Nowak, J.
Powiązania:: https://bibliotekanauki.pl/articles/139189.pdf
Data publikacji:: 2013
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: tonstein
Załęże beds
goyazite
gorceixite
apatite
phosphorus
barium
strontium
warstwy załęskie
goyazyt
apatyt
fosfor
bar
stront
Opis:: The paper presents results of research on tonstein, which constitutes an interburden in coal seam 405 at the Sośnica - Makoszowy coal mine, Makoszowy field (mining level 600 m), Upper Silesia, southern Poland. The mineral and chemical compositions of the tonstein differ from the typical compositions described earlier for tonsteins from Upper Silesia Coal Basin area. Additionally, minerals present in the tonsteins include kaolinite, quartz, kaolinitised biotite and feldspars. The presence of the phosphatic minerals apatite and goyazite has been recognized. The presence of gorceixite and crandallite is also possible. The contents of CaO (5.66 wt%) and P²O⁵ (6.2 wt%) are remarkably high. Analysis of selected trace elements demonstrated high contents of Sr (4937 ppm) and Ba (4300 ppm), related to the phosphatic minerals. On the basis of mineral composition the tonstein has been identified as a crystalline tonstein, transitional to a multiplied one.
Źródło:: Acta Geologica Polonica; 2013, 63, 2; 271-281
0001-5709
Pojawia się w:: Acta Geologica Polonica
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 8.

Tytuł:: Finite element analysis of load characteristic of shield bolter miner cutting head under complex coal seam condition
Autorzy:: Qiao, S.
Xia, Y. M.
Liu, Z. Z.
Liu, J. S.
Ning, B.
Wang, A. L.
Powiązania:: https://bibliotekanauki.pl/articles/89071.pdf
Data publikacji:: 2017
Wydawca:: Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:: complex coal seam
shield bolter miner
load characteristic
specific energy
load fluctuation
Opis:: Aiming at the complex conditions of the first shielded bolter miner in the actual work, the mechanical model of bolter miner cutting head was established. Based on cutting mechanism of the conical pick and the cutting head, the cutting head load and torque analysis model under complex coal seam were established. The dynamic characteristics of load and torque in the process of cutting head are analyzed under three different working conditions of cutting roof-coal layers, coal-floor layers and coal seam by finite element method. The results show that when the damage variable D=1, the coal-rock completely lacks the bearing capacity, and it forms arc-shaped crushing groove on the coal-rock. The large difference of torque between roof-coal layers and the roof-coal layers in the conical pick is 112 Nm, which indicates that the cutting head has the best performance with cutting the coal seam first and then cutting the rock. In the process of excavation, the load fluctuation coefficient of cutting the coal-floor layers and roof-coal layers is about 1.2 times of that of the coal seam. The results can provide a reference for the efficient cutting and performance evaluation of the bolter miner.
Źródło:: Mining Science; 2017, 24; 85-97
2300-9586
2353-5423
Pojawia się w:: Mining Science
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 9.

Tytuł:: A proper borehole pattern design for coal seam methane drainage in Tabas coal mine using Comsol Multiphysics
Autorzy:: Bagherzadeh, Ali
Najafi, Mehd
Marji, Mohammad Fatehi
Noroozi, Mehdi
Powiązania:: https://bibliotekanauki.pl/articles/2201375.pdf
Data publikacji:: 2022
Wydawca:: Główny Instytut Górnictwa
Tematy:: numerical modeling
borehole patterns
COMSOL Multiphysics
CFD simulation
coal gas drainage
modelowanie numeryczne
schematy otworów wiertniczych
symulacja CFD
odmetanowanie
Opis:: Optimizing the operational parameters of the borehole pattern in the coal seam includes the maximum amount of gas to be drained with the least amount of drilling, investment, and drainage time. The main purpose of this research is to properly design the drainage borehole pattern in the C1 coal seam of the Tabas coal mine. In this research, the Comsol Multiphysics software was used for numerical modeling of the boreholes. According to the method of diffusion of methane gas in a coal seam, the reduction of methane gas concentration and the amount of gas released from the coal blocks were approximated. For the gas drainage boreholes, the three patterns of the rectangular, parallelogram, and triangular forms were considered. Also, the boreholes were modeled with the three diameters of 76, 86, and 96 mm. This modeling was performed for 180 days of drainage operation and showed that the triangular pattern was more suitable than the other two patterns. The presented model is applicable in coal mines where gas drainage operations are necessary and helps engineers design the patterns of drainage boreholes to maximize their gas drainage efficiency.
Źródło:: Journal of Sustainable Mining; 2022, 21, 1; 54--64
2300-1364
2300-3960
Pojawia się w:: Journal of Sustainable Mining
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 10.

Tytuł:: Theoretical analysis of support stability in large dip angle coal seam mined with fully-mechanized top coal caving
Autorzy:: Ji, Yucheng
Zhang, Yinghua
Huang, Zhian
Shao, Zhenlu
Gao, Yukun
Powiązania:: https://bibliotekanauki.pl/articles/1402319.pdf
Data publikacji:: 2020
Wydawca:: Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:: large dip angle
hydraulic support
stability
coal
Opis:: Support stability is critical to ensure fully-mechanized top coal caving of large dip angle coal seam. To obtain the relations between each factor and hydraulic support stability, the mechanic model of large dip angle coal seam along face dip and strike was built to analyze support stability, including antitoppling, anti-slip, and anti-rotation of supports. The result indicates: Along the face dip, the suport stability was negatively correlated with dip angle; Higher top caving means lower anti-rotation at suport tail; With initial support force and working resistance of supports enhanced, the anti-slip, and antirotation stability of supports can be risen significantly. Along the strike, the critical toppling angle was proportional to dip angle, mining height, support weight, support width and support force; The critica slip angle was positive correlation with support force, friction coefficient of roof and supports. According to the results of both mechanical analysis and engineering projects, support stability in large dip angle can be risen efficiently and supports slipping, toppling and rotation can be avoided by selecting proper technical methods and equipment, like enhancing initial support force appropriately.
Źródło:: Mining Science; 2020, 27; 73-87
2300-9586
2353-5423
Pojawia się w:: Mining Science
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 11.

Tytuł:: A 90 m-thick coal seam in the Lubstów lignite deposit (Central Poland): palynological analysis and sedimentary environment
Autorzy:: Durska, E.
Powiązania:: https://bibliotekanauki.pl/articles/2060212.pdf
Data publikacji:: 2008
Wydawca:: Państwowy Instytut Geologiczny – Państwowy Instytut Badawczy
Tematy:: Miocene
Konin region
pollen
tree islands
Opis:: A 90 m-thick brown coal seam, the result of organic matter deposition in a fault-trough, is exploited in an open cast mine at Lubstów (Central Poland). Palynological analysis was conducted in order to determine which plants were the source of or ganic matter forming such a thick coal bed. The pollen spectrum is dominated by the gymnosperm pollen Inaperturopollenites, produced by trees closely related to the extant genera Taxodium and Glyptostrobus, the dominant constituents of swamp forests in SE North America and SE Asia today. However, the lack of xylites and preserved tissues in the coal does not support the conception of a swamp forest as the peat-producing community. There is also a significant percent age of angiosperm pollen in the coal, mainly from the groups: Castaneoideapollis, Tricolporopollenites exactus and T. pseudocingulum. The plants producing these pollen were probably the main constituent of the peat-producing community. The community shows signs of a shrub swamp with local tree islands and a low water table. Evidence for this also includes the de trital type of coal, the lack of preserved plant tissues and the presence of fungal remains. These character is tics show the existence of aerobic zones at the time of peat production. The peat was probably derived from angiosperms. Dome-shaped forms in the up per part of the de posit are the re mains of tree is lands. As de tri tus ac cu mu la tion is very rapid on the sur faces of pres ent-day tree is lands, a sim i lar rate of de po si tion may have taken place dur ing peat pro duc tion at Lubstów. This, com bined with sub si dence in the fault-trough, ex plains the great thick ness of the coal bed.
Źródło:: Geological Quarterly; 2008, 52, 3; 281-281
1641-7291
Pojawia się w:: Geological Quarterly
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 12.

Tytuł:: An expert system for equipment selection of thin coal seam mining
Specjalistyczny system doboru sprzętu do wydobycia cienkich pokładów węgla
Autorzy:: Wang, Chen
Chen, Jie
Liu, Yong
Jiang, Chengyu
Powiązania:: https://bibliotekanauki.pl/articles/217010.pdf
Data publikacji:: 2019
Wydawca:: Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:: expert system
thin coal seam
equipment selection
equipment matching
decision making software
field application
system ekspercki
cienki pokład węgla
dobór sprzętu
dopasowanie sprzętu
oprogramowanie do podejmowania decyzji
zastosowanie w praktyce
Opis:: As one of the key techniques in the fully mechanized mining process, equipment selection and matching has a great effect on security, production and efficiency. The selection and matching of fully mechanized mining equipment in thin coal seam are restricted by many factors. In fully mechanized mining (FMM) faced in thin coal seams (TCS), to counter the problems existing in equipment selection, such as many the parameters concerned and low automation, an expert system (ES) of equipment selection for fully mechanized mining longwall face was established. A database for the equipment selection and matching expert system in thin coal seam, fully mechanized mining face has been established. Meanwhile, a decision-making software matching the ES was developed. Based on several real world examples, the reliability and technical risks of the results from the ES was discussed. Compared with the field applications, the shearer selection from the ES is reliable. However, some small deviations existed in the hydraulic support and scraper conveyor selection. Then, the ES was further improved. As a result, equipment selection in fully mechanized mining longwall face called 4301 in the Liangshuijing coal mine was carried out by the improved ES. Equipment selection results of the interface in the improved ES is consistent with the design proposal of the 4301 FMM working face. The reliability of the improved ES can meet the requirements of the engineering. It promotes the intelligent and efficient mining of coal resources in China.
Dobór sprzętu, jako jedna z kluczowych technik w pełni zmechanizowanego procesu wydobycia, ma ogromny wpływ na bezpieczeństwo, produkcję i wydajność. Wybór i dopasowanie w pełni zmechanizowanego sprzętu górniczego w cienkim pokładzie węgla jest ograniczone przez wiele czynników. W przypadku całkowicie zmechanizowanej ściany wydobywczej węgla (FMM) w cienkich pokładach (TCS) przeciwdziałanie problemom związanym z wyborem sprzętu, takim jak m.in.: wielość rozpatrywanych parametrów i niska automatyzacja, ustanowiono system ekspercki (ES) doboru sprzętu do w pełni zmechanizowanej ściany wydobywczej. Utworzono bazę danych systemu doboru i dopasowania systemu eksperckiego w cienkich pokładach węgla w pełni zmechanizowanej ściany wydobywczej. Jednocześnie opracowano oprogramowanie do podejmowania decyzji, dopasowane do ES. Na podstawie kilku rzeczywistych przykładów omówiono wiarygodność i ryzyko techniczne związane z wynikami ES. W porównaniu z zastosowaniem obecnym, wybór kombajnu systemem eksperckim (ES) jest niezawodny. Wystąpiły jednak pewne niewielkie odchylenia w wyborze stojaków hydraulicznych i przenośnika zgarniającego, następnie ES został ulepszony. W rezultacie poprawiono wybór sprzętu w całkowicie zmechanizowanej ścianie wydobywczej o nazwie 4301 w kopalni Liangshuijing. Interfejs wyników wyboru sprzętu w ulepszonym ES jest zgodny z propozycją projektu 4301 FMM roboczej ściany wydobywczej. Niezawodność ulepszonego ES może spełniać wymagania inżynieryjne. Promuje inteligentne i wydajne wydobycie zasobów węgla w Chinach.
Źródło:: Gospodarka Surowcami Mineralnymi; 2019, 35, 3; 143-162
0860-0953
Pojawia się w:: Gospodarka Surowcami Mineralnymi
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 13.

Tytuł:: Internal mechanism of asymmetric deformation and failure characteristics of the roof for longwall mining of a steeply dipping coal seam
Autorzy:: Luo, Shenghu
Wang, Tong
Wu, Yongping
Huangfu, Jingyu
Zhao, Huatao
Powiązania:: https://bibliotekanauki.pl/articles/1853910.pdf
Data publikacji:: 2021
Wydawca:: Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:: odkształcenie
pokłady węgla
szyb kopalniany
steeply dipping seam
gangue
slip filling
deformation failure
main roof
angle effect
Opis:: Stability control of the roof is the key to safe and efficient mining of the longwall working face for a steeply dipping coal seam. In this study, a comprehensive analysis was performed on the roof destruction, migration, and filling characteristics of a steeply dipping longwall working face in an actual coalmine. Elastic foundation theory was used to construct a roof mechanics model; the effect of the coal seam inclination angle on the asymmetric deformation and failure of the roof under the constraint of an unbalanced gangue filling was considered. According to the model, increasing the coal seam angle, thickness of the immediate roof, and length of the working face as well as decreasing the thickness of the coal seam can increase the length of the contact area formed by the caving gangue in the lower area of the slope. Changes to the length of the contact area affect the forces and boundary conditions of the main roof. Increasing the coal seam angle reduces the deformation of the main roof, and the position of peak deflection migrates from the middle of the working face to the upper middle. Meanwhile, the position of the peak rotation angle migrates from the lower area of the working face to the upper area. The peak bending moment decreases continuously, and its position migrates from the headgate T-junction to the tailgate T-junction and then the middle of the working face. Field test results verified the rationality of the mechanics model. These findings reveal the effect of the inclination coal seam angle on roof deformation and failure and provide theoretical guidance for engineering practice.
Źródło:: Archives of Mining Sciences; 2021, 66, 1; 101-124
0860-7001
Pojawia się w:: Archives of Mining Sciences
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 14.

Tytuł:: Study of the impact of exploitation structures on pressure distribution and adsorbed methane content in coal seams using dynamic flow models. A case study
Autorzy:: Szott, Wiesław
Miłek, Krzysztof
Łętkowski, Piotr
Gołąbek, Andrzej
Powiązania:: https://bibliotekanauki.pl/articles/1402316.pdf
Data publikacji:: 2020
Wydawca:: Politechnika Wrocławska. Wydział Geoinżynierii, Górnictwa i Geologii. Instytut Górnictwa
Tematy:: methane drainage
coal seam
exploitation structures
desorption
reservoir simulation
Opis:: One of the most serious difficulties encountered during the estimation of results of various methods of methane drainage from coal seams is the determination of the initial condition of the analysed coal seam prior to commencement of the actual process of methane drainage. It is well known that the exploitation operation in adjacent coal seams, as well as preparatory works in the analysed seam may significantly modify the original state of methane adsorption in that seam, as well as influence the distribution of pore pressure and saturation of its natural fractures with fluids (gas, water). This state is of dynamic nature and depends on a long and complex history of the mining activity in the analysed facility and its surrounding. Detailed specification of the above condition is usually replaced by qualitative and very approximate models, which does not allow for consideration of the process preceding the methane drainage. The subject of the paper is the quantitative evaluation of the initial conditions for a coal seam with the use of dedicated simulation models of the analysed seam along with its broad surroundings. Results of this modelling including modifications of appropriate transport parameters of layers between the seams and their influence on detailed distribution of pore pressures, levels of methane desorption from the coal matrix, directions of reservoir fluids flow (methane, water) and saturation with these fluids in natural fractures of the selected seam, as well as in the pores of overburden and underburden rocks will be thoroughly analysed for determination of spacious and temporal effects of the mining activities in terms of their influence on the selected seam.
Źródło:: Mining Science; 2020, 27; 133-153
2300-9586
2353-5423
Pojawia się w:: Mining Science
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Skocz do pozycji: 15.

Tytuł:: Petrographic and mineral variability of the rocks accompanying selected coal seams of the Poruba beds and their influence of the trace elements content
Zróżnicowanie petrograficzno-mineralogiczne skał współwystępujacych z wybranymi pokładami węgla z warstw porębskich i jego wpływ na zawartość pierwiastków śladowych
Autorzy:: Kokowska-Pawłowska, M.
Powiązania:: https://bibliotekanauki.pl/articles/215942.pdf
Data publikacji:: 2015
Wydawca:: Polska Akademia Nauk. Instytut Gospodarki Surowcami Mineralnymi i Energią PAN
Tematy:: rocks accompanying
roof rocks
floor rocks
band rocks
Poruba beds
coal seam 610
coal seam 620
coal seam 630
skały współwystępujące
skały stropowe
skały spągowe
przerosty
pierwiastki śladowe
warstwy porębskie
pokład węgla 610
pokład węgla 620
pokład węgla 630
Opis:: The rocks accomanying with coal in selected Poruba beds (610, 620, 630 coal seams) showed the diversification of mineralogical and petrographic composition. Most often there are claystones (including syderitic claystones), rarely mudstones (including syderitic mudstones) and sporadically sandstones. The presence of tonstein was also found. In the rocks was found variability of trace elements content (Ba, Zn, Mn, V, Cr, Cu, Ni, Pb, As, Ga, B, Co, Ge, Be, Li, Cd, Ag, Sr – in order of decreasing participation) dependent on rocks petrographic variety. Large part of elements showed high and often dominant participation in claystones. Correlation analysis between trace elements concentration and main minerals content confirmed the affinity of many trace elements with clay minerals, carbonates and organic substance. Noteworthy, the correlation of many elements with mica in syderitic claystones.
Skały współwystępujące z węglem w wybranych pokładach warstw porębskich (610, 620, 630) reprezentowane są najczęściej przez iłowce oraz iłowce syderytyczne, a rzadziej przez mułowce i mułowce syderytyczne. Sporadycznie występują piaskowce. Stwierdzono także występowanie przerostu z tonsteinem. Zależnie od odmiany petrograficznej skał stwierdzono w nich zróżnicowanie zawartości pierwiastków śladowych (Ba, Zn, Mn, V, Cr, Cu, Ni, Pb, As, Ga, B, Co, Ge, Be, Li, Cd, Ag, Sr – w kolejności malejącego udziału). Znaczna część pierwiastków wykazała wysoki i często dominujący udział w iłowcach. Stwierdzono także regionalne zróżnicowanie zawartości pierwiastków śladowych w skałach. Badania korelacji pomiędzy zawartością pierwiastków śladowych a zawartością głównych minerałów w skałach potwierdziły powinowactwo wielu pierwiastków śladowych z substancją organiczną, minerałami ilastymi i węglanami. Zwraca uwagę występowanie korelacji licznych pierwiastków śladowych z substancją organiczną (węglem) przy stosunkowo niewielkiej liczbie pierwiastków korelujących z minerałami ilastymi.
Źródło:: Gospodarka Surowcami Mineralnymi; 2015, 31, 2; 73-92
0860-0953
Pojawia się w:: Gospodarka Surowcami Mineralnymi
Dostawca treści:: Biblioteka Nauki

Artykuł

Zmień widok

na półce

Informacja

Wyszukujesz frazę "coal seam" wg kryterium: Wszystkie pola

Źródło danych

Dostawca treści

Kolekcja

Rok wydania

Wydawca

Temat

Autor

Typ dokumentu

Język