scholarly journals Extraction of Coal from Steeply Inclined Coal Seams, Using a Fully Mechanised Sublevel Caving Mining System in the Kazimierz-Juliusz Coal Mine

2020 ◽  
Author(s):  
Zbigniew Rak ◽  
Jerzy Stasica ◽  
Zbigniew Burtan ◽  
Dariusz Chlebowski
Keyword(s):  
Coal Mine ◽  
Mining Industry ◽  
Extraction Process ◽  
Hard Coal ◽  
Mining System ◽  
Spoil Heap ◽  
Coal Cutting ◽  
Sublevel Caving ◽  
The Face ◽  
Mining Face

Abstract Mining of thick and steeply inclined hard coal deposits belongs to some of the most difficult engineering challenges. The Sublevel Caving system, originating from the ore mining industry, is one of the systems applied in such cases. That system has been used in coal mining for more than sixty years, although it became fully mechanised only at the beginning of the present century. The unique mechanical mining face mining method was applied for the first time in the Kazimierz-Juliusz Coal Mine in Poland to cut a deposit 20 m thick and inclined at more than 40°. The longwall protection system consisted of two mechanised support sets that were coordinated with the chain conveyor. The conveyor crossover was located on the spoil heap. Coal cutting was performed by blasting and coal was loaded gravitationally directly onto the conveyor. Using that mechanical system, a three-person strong face team obtained the output at the level of 600 to 1,000 Mg per day. About a dozen of years of experience gained in the Kazimierz-Juliusz Coal Mine allowed the engineers to improve the extraction process and reduce the face costs to the level of about 6 euros/Mg. Another essential achievement included elimination of serious accidents at the mining face. In addition to the process de-scription, this paper contains selected production results obtained upon the implementation of the sublevel caving system in the Kazimierz-Juliusz Coal Mine.

The Research on Geological Characteristics of the Dafosi Coal Mine Company 40110 Working Face

2012 ◽  
Vol 170-173 ◽  
pp. 1273-1276
Author(s):  
Jia Ming Han
Keyword(s):  
Coal Mine ◽  
Relative Movement ◽  
Practical Application ◽  
Wing Area ◽  
Daily Production ◽  
The Third ◽  
Geological Characteristics ◽  
Working Face ◽  
Sublevel Caving ◽  
Mining Face

40110 working face is arranged as the third Mechanized sublevel caving mining face in the 401 east-wing area along the coal seam by Dafosi company of the Binchang Mining Group Corporation. According to the conclusion based on the research about Binchang area coal geology not only shows the roof and floor lithology, structure, hydrology, the gas, dust features and so on but also proposes mining roadway supporting schemes and putting them into practice. Practical application shows that roadway supporting schemes effectively control the two-sided displacement and relative movement of the roof and floor to ensure the daily production of coal mine.

scholarly journals Methodology of Estimation of Methane Emissions from Coal Mines in Poland

2014 ◽  
Vol 36 (1) ◽  
pp. 89-101 ◽  
Author(s):  
Renata Patyńska
Keyword(s):  
Kyoto Protocol ◽  
Methane Emission ◽  
Emission Factor ◽  
Coal Mines ◽  
Mining Industry ◽  
Methane Emissions ◽  
Hard Coal ◽  
Mining System ◽  
Upper Silesian Coal Basin ◽  
Ipcc Guidelines

Abstract Based on a literature review concerning methane emissions in Poland, it was stated in 2009 that the National Greenhouse Inventory 2007 [13] was published. It was prepared firstly to meet Poland’s obligations resulting from point 3.1 Decision no. 280/2004/WE of the European Parliament and of the Council of 11 February 2004, concerning a mechanism for monitoring community greenhouse gas emissions and for implementing the Kyoto Protocol and secondly, for the United Nations Framework Convention on Climate Change (UNFCCC) and Kyoto Protocol. The National Greenhouse Inventory states that there are no detailed data concerning methane emissions in collieries in the Polish mining industry. That is why the methane emission in the methane coal mines of Górnośląskie Zagłębie Węglowe - GZW (Upper Silesian Coal Basin - USCB) in Poland was meticulously studied and evaluated. The applied methodology for estimating methane emission from the GZW coal mining system was used for the four basic sources of its emission. Methane emission during the mining and post-mining process. Such an approach resulted from the IPCC guidelines of 2006 [10]. Updating the proposed methods (IPCC2006) of estimating the methane emissions of hard coal mines (active and abandoned ones) in Poland, assumes that the methane emission factor (EF) is calculated based on methane coal mine output and actual values of absolute methane content. The result of verifying the method of estimating methane emission during the mining process for Polish coal mines is the equation of methane emission factor EF.

scholarly journals Supporting problems at an island mining face in Shanxi, China. Case study based on field observation

2019 ◽  
Vol 2 (1) ◽  
pp. 257-267
Author(s):  
Xiaowei Feng
Keyword(s):  
Field Observation ◽  
Rock Bolt ◽  
Shanxi Province ◽  
Coal Cutting ◽  
Long Time ◽  
The Face ◽  
Bearing Force ◽  
Face Plate ◽  
Mining Face ◽  
Cable Bolt

Abstract In this paper, field observation is conducted in Fujiaao Coal Mine, Linfen city in Shanxi province, China, which is unique because of its island-typed mining layout. Firstly, geology, layout of the coal cutting face, supporting pattern are presented and details are also provided. Then the problems are discussed and analyzed based on existing bolting theories. It finds out the length of the cable bolt is too long, which requires long time to drill boreholes, whilst the effectiveness is limited due to the illogical combination between cable bolt function zone and rock bolt function zone. Also, the face place allocated to rock bolt is very likely to cause line contact between its edge and steel belt, thus the bearing force is tremendously weakened and solely determined by strength of belt. Furthermore, field observation proves the low active supporting effects to roof, thus leading obvious roof sink even without the disturbance of mining activity. Eventually, some solutions are proposed with the intention to improve the situation based on the economic and technical considerations, including bolting in humidity environment, rational cable bolt length, wise choice of face plate, and ways to increase pretension force. The viewpoints and comments of this study can be referred by practitioners in coal mines sharing same difficulties.

scholarly journals Progressive backfill mining technology with split and two wings

2021 ◽  
Vol 303 ◽  
pp. 01036
Author(s):  
Ma Qihua ◽  
Ma Weixiang ◽  
Gong Jianxiang
Keyword(s):  
Coal Mining ◽  
Coal Mine ◽  
Large Scale ◽  
Mining Industry ◽  
Underground Water ◽  
Mining System ◽  
Mining Technology ◽  
Soil And Water Loss ◽  
Efficient Recovery ◽  
Massive Accumulation

: With the large-scale development of the mining industry, soil and water loss, environmental pollution and other geological disasters ac-companied by coal mining are continually increasing. Therefore, while promoting coal mine production by relying on scientific and technological progress, measures to control and reduce the resulting disasters cannot be ignored. In this paper, taking Xiezhuang coal mine as an example, we have combined its actual production conditions to solve the environmental problems caused by the massive accumulation of surface gangue in Xiezhuang coal mine. Moreover, to improve the efficient recovery of coal resources and ensure the safety of deep resources mining, and to reduce the rock burst and the damage caused to the underground water body, a re-search on forward filling mining technology with split-wing is put forward. This paper mainly discusses the related technologies and laws of forward filling mining method with split-wing, coal mining system, technological process, and filling mining.

scholarly journals Combination of Pre-Pulse and Constant Pumping Rate Hydraulic Fracturing for Weakening Hard Coal and Rock Mass

Energies ◽  
2020 ◽  
Vol 13 (21) ◽  
pp. 5534
Author(s):  
Qingying Cheng ◽  
Bingxiang Huang ◽  
Luying Shao ◽  
Xinglong Zhao ◽  
Shuliang Chen ◽  
...  
Keyword(s):  
Rock Mass ◽  
Hydraulic Fracturing ◽  
Coal Mine ◽  
Longwall Mining ◽  
Block Size ◽  
Hard Coal ◽  
Pumping Rate ◽  
Thick Coal Seam ◽  
Coal Rock ◽  
Mining Face

The weakening of hard coal–rock mass is the core common problem that is involved in the top coal weakening in hard and thick coal seams, the hard roof control during the initial mining stage in the longwall mining face, and the hanging roof control in the gob of non-coal mine. Based on the characteristics of pulse hydraulic fracturing and constant pumping rate hydraulic fracturing, a weakening method for hard coal–rock mass by combining pre-pulse and constant pumping rate hydraulic fracturing is proposed. A complete set of equipment for the combined pulse and constant pumping rate hydraulic fracturing construction in the underground coal mine is developed. The pulse and constant pumping rate hydraulic fracturing technology and equipment were applied in the top coal weakening of the shallow buried thick coal seam. Compared with no weakening measures for top coal, the average block size of the top coal caving was reduced by 42% after top coal hydraulic fracturing. The recovery rate of the top coal caving mining face reached 85%, and it increased by 18% after hydraulic fracturing.

scholarly journals Directional Hydraulic Fracturing (DHF) of the Roof, as an Element of Rock Burst Prevention in the Light of Underground Observations and Numerical Modelling

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 562
Author(s):  
Marek Jendryś ◽  
Andrzej Hadam ◽  
Mateusz Ćwiękała
Keyword(s):  
Rock Mass ◽  
Hydraulic Fracturing ◽  
Coal Mining ◽  
Rock Burst ◽  
Coal Mine ◽  
Seismic Activity ◽  
Black Coal ◽  
Directional Hydraulic Fracturing ◽  
Before And After ◽  
The Face

The following article analyzes the effectiveness of directional hydraulic fracturing (DHF) as a method of rock burst prevention, used in black coal mining with a longwall system. In order to define changes in seismic activity due to DHF at the “Rydułtowy” Black Coal Mine (Upper Silesia, Poland), observations were made regarding the seismic activity of the rock mass during coal mining with a longwall system using roof layers collapse. The seismic activity was recorded in the area of the longwall itself, where, on a part of the runway, the rock mass was expanded before the face of the wall by interrupting the continuity of the rock layers using DHF. The following article presents measurements in the form of the number and the shock energy in the area of the observed longwall, which took place before and after the use of DHF. The second part of the article unveils the results of numerical modeling using the discrete element method, allowing to track the formation of goafs for the variant that does not take DHF into consideration, as well as with modeled fractures tracing DHF carried out in accordance with the technology used at “Rydułtowy” coal mine.

Microbial Methane Formation from Hard Coal and Timber in an Abandoned Coal Mine

2008 ◽  
Vol 25 (6) ◽  
pp. 315-321 ◽  
Author(s):  
Martin Krüger ◽  
Sabrina Beckmann ◽  
Bert Engelen ◽  
Thomas Thielemann ◽  
Bernhard Cramer ◽  
...  
Keyword(s):  
Coal Mine ◽  
Hard Coal ◽  
Methane Formation ◽  
Abandoned Coal Mine

scholarly journals MODERNIZATION OF THE MINING SYSTEM OF SMALL DEPOSITS OF RICH COPPER PYRITE ORES

2020 ◽  
Vol 12 (3) ◽  
pp. 444-453
Author(s):  
Igor SOKOLOV ◽  
◽  
Yury ANTIPIN ◽  
Artem ROZHKOV ◽  
◽  
...  
Keyword(s):  
Mathematical Modeling ◽  
Rock Mass ◽  
Average Length ◽  
Thickness Variation ◽  
Chamber System ◽  
Mining Operations ◽  
Mining System ◽  
Ore Body ◽  
Experimental Block ◽  
Sublevel Caving

The purpose work. Substantiation and selection of a safe and effective option of mining technology of the experimental block in the pilot industrial mining of the Skalistoe deposit. Method of research. Analysis and synthesis of project solutions, experience in mining inclined low-thickness ore bodies, economic and mathematical modeling and optimization of the parameters of options mining systems in the conditions of the experimental block. Results of research. As a result of research it was established: - the sublevel caving mining system with the parameters adopted in the project does not guarantee the completeness of the extraction of reserves and the effectiveness of mining operations. Project indicators of extraction by sublevel caving technology with frontal ore drawing are overestimated and difficult to achieve in these geological and technical conditions (combination of low thickness and angle of ore body); project scheme for the delivery and transportation of rock mass seems impractical due to the significant volume of heading workings and increased transportation costs; - eight technically rational options of various mining systems were constructed, most relevant to the geological and technical conditions of the deposit. Five variants of the sublevel chamber system and pillar caving, a project variant of sublevel caving technology with frontal ore drawing and two options flat-back cut-and-fill system were considered; - for mining the Skalistoe deposit, according to the results of economic and mathematical modeling, optimal by the criterion of profit per 1 ton of balance reserves of ore is a option of the technology of chamber extraction with dual chambers, frontal drawing of ore by remote-controlled load-haul-dump machine and subsequent pillars caving, as having the greatest profit; - the calculations justified stable spans of dual chambers (25.3 m) and the width of panel pillars (3 m). With an allowable span of 25.3 m, the roof of the dual chambers will be stable with a safety factor of 1.41, and a panel pillar with a width of 3 m has a sufficient margin of safety (more than 1.6) in the whole range of ore body thickness variation; - the proposed scheme of delivery and transportation of rock mass, which allows to reduce the volume of tunnel works by 26% and the average length of transportation by 10-15% compared with the project. Findings. Developed in the process of modernization the technology sublevel chamber system with double-chamber, compared with the project technology, it is possible to significantly increase the efficiency of mining of the low thickness deposit of rich ores Skalistoe by reducing the specific volume of preparatory-rifled work by 34%, the cost of mined ore by 12%, losses and ore dilution – by 2 and 2.9 times, respectively.

scholarly journals How Miners and Other Professional Groups Perceive the Benefits and Risks of Hard Coal Mining: A Study on the Role of the Affect Heuristic

2021 ◽  
Vol 12 ◽  
Author(s):  
Piotr Zielonka ◽  
Wojciech Białaszek ◽  
Bartłomiej Dzik ◽  
Katarzyna Wybrańczyk
Keyword(s):  
Coal Mining ◽  
Public Support ◽  
Mining Industry ◽  
Hard Coal ◽  
Safety Hazards ◽  
Information Campaigns ◽  
Professional Groups ◽  
Affect Heuristic ◽  
Hard Coal Mining

The problems that are inherent in the green shift of the energy sectors are particularly visible in countries where the hard coal mining industry plays an important role in the economy and society. For any transition to be successful, public support is crucial. This empirical study shows that – as a consequence of the affect heuristic – those who perceive hard coal mining as beneficial tend to minimize both its detrimental environmental impacts and its personal safety hazards. Ignoring the affect heuristic may have retarded transformations and led to a failure of many information campaigns.

Sign in / Sign up

Export Citation Format

Share Document