Technology of the north Bohemian brown coal mining district open-pit mines, Czechoslovakia

1991 ◽  
Vol 28 (5) ◽  
pp. 319
Keyword(s):  
Coal Mining ◽  
Brown Coal ◽  
Open Pit ◽  
Mining District ◽  
Open Pit Mines ◽  
The North

scholarly journals Optimization of Inner Dumping Uncovered Height with Partially Covered End Wall in Adjacent Surface Coal Mining Districts

2018 ◽  
Vol 2018 ◽  
pp. 1-9 ◽  
Author(s):  
Li Ma ◽  
Zhiguo Chang ◽  
Kemin Li ◽  
Shuangshuang Xiao ◽  
Xiaohua Ding
Keyword(s):  
Coal Mining ◽  
Minimum Cost ◽  
Open Pit ◽  
Mining District ◽  
Wall Model ◽  
Surface Coal Mining ◽  
Surface Coal Mine ◽  
Mining Districts ◽  
End Wall

In order to analyze the relationships of inner dumping with covered end wall in adjacent surface coal mining districts, a trough-shaped uncovered end wall model was put forward. A mathematical model concerning uncovered end wall height (UEWH) was established based on minimum cost method. The inner dump capacity was considered regarding its effect on UEWH. Besides, a comprehensive model was established for calculating optimal UEWH in inner dumping with partially covered end wall mode and a shifting distance optimization model based on cost compensation method for building a provisional haulage system to connect inner dump. As for case study in Huolinhe number 1 surface coal mine, research results show that optimal UEWH was 225 m between North Pit and South Pit whereas in number 3 mining district of North Open-Pit Mine it was 23.50 m when making its transition from cross mining to mining along strike. Nevertheless, due to limited inner dump capacity, inner dump height in South and North mining districts shall be appropriately increased and closed pits from earlier period shall be fully utilized to make room for inner dumping with partially uncovered end walls.

Numerical Simulation of Slope Stability Analysis of Open Pit Coal Mine Based on MIDAS/GTS

2012 ◽  
Vol 256-259 ◽  
pp. 193-197
Author(s):  
Chong Xian Liu ◽  
Yong Tao Gao
Keyword(s):  
Slope Stability ◽  
Coal Mine ◽  
Mining Area ◽  
Slope Instability ◽  
Open Pit ◽  
Shanxi Province ◽  
North Slope ◽  
Mining District ◽  
The North

Based on mining area end slope stability evaluation engineer- ing of Pingshuo East open pit coal mine in Shanxi Province, ac- cording to the status quo of the North Slope of the first mining district of the East open pit coal mine as well as engineering g- eological investigation results, this article selected a represen- tative cross-section of the North Slope,adopted processing fu- nctions of finite element analysis software MIDAS/GTS, and re- spectively analyze slope stability under three conditions of the mining area of the initial excavation,backfilling and disposal,a- nd follow-up excavation.The paper concluded that Initial exca- vation caused slope instability; backfill slope is stable after di- sposal; follow-up excavation has essentially no effect on slope stability. The establishment and analysis are much closer to t- he real situation, objectively reflect the distribution of slope s- tability of the East open pit coal mine, and provide a design for open pit production safety.

scholarly journals Miocene carpological floras of the Konin region (Central Poland)

2017 ◽  
Vol 57 (1) ◽  
pp. 39-100 ◽  
Author(s):  
Rafał Kowalski
Keyword(s):  
Plant Communities ◽  
Brown Coal ◽  
Floristic Composition ◽  
Open Pit ◽  
Raised Bog ◽  
Open Pit Mines ◽  
Zonal Vegetation ◽  
Plant Remains ◽  
First Time ◽  
Warm Temperate

AbstractCarbonaceous, three-dimensionally preserved macroscopic plant remains from the Lubstów, Gosławice and Pątnów brown coal open-pit mines are described and illustrated, providing a comprehensive elaboration of the middle Miocene carpological floras of the Konin region. The diaspores represent the following families: Pinaceae, Sciadopityaceae, Cupressaceae, Annonaceae, Cabombaceae, Nymphaeaceae, Araceae, Typhaceae, Cyperaceae, Vitaceae, Rosaceae, Rhamnaceae, Fagaceae, Myricaceae, Cornaceae, Nyssaceae, Symplocaceae, Ericaceae, Araliaceae, and Adoxaceae. Forty-two species were recognised or documented for the first time in the Konin region. Two genera, three species and three morphotypes are described as new taxa.Most of these plant remains represent azonal vegetation. Ericaceous bogs, pine bogs and mixed coniferous bogs, accompanied byGyptostrobusswamp forests and various aquatic plant communities, are suggested as the most widespread vegetation types. Remains representing mesophytic, zonal vegetation, resembling extant evergreen broad-leaved and mixed mesophytic forests, are sparse. ASciadopitysraised bog, a mixed coniferous bog subtype, was one of the important biomass sources forming the brown coal of the I-Middle Polish seam group. Other bog types recognised in Lubstów presumably also played a part in this process. Wildfire is suggested as an important factor controlling the Miocene vegetation of the Konin region.The floristic composition and lithostratigraphy indicate the Badenian age (16.3–12.8 Ma) for the studied floras, but radiometric data suggest that two Lubstów floras are older and one is younger than 13.6 Ma. Biostrati-graphically, Lubstów floras were correlated with the Klettwitz – Salzhausen floristic complex. Based on several climatic indicators and biostratigraphic correlation, the climate is estimated to have been humid, warm-temperate or subtropical.The upper Miocene lower Rhenish Basin floras are the most comparable in floristic and plant communities’ composition. Tropical – subtropical, Mediterranean and extinct genera represent approximately 40% of the genera identified in Lubstów.

scholarly journals The Operation of Bucket Wheel Excavators When Encountering Inclusions with Excessive Mining Resistance

2018 ◽  
Vol 8 (1) ◽  
pp. 15-20
Author(s):  
József András ◽  
József Kovács
Keyword(s):  
Brown Coal ◽  
Frequent Occurrence ◽  
Open Pit ◽  
Operating Environment ◽  
Geological Structures ◽  
Research Project ◽  
Open Pit Mines ◽  
Continuous Increase ◽  
Mining Conditions

Abstract The Bucket Wheel Excavator (BWE) is the main piece of harvesting equipment used in open-pit lignite or brown coal open-pit mines worldwide. Despite the continuous increase in size, productivity and technical sophistication in recent decades, they have not adapted to the changes of operating environment. In this respect, the increasingly frequent occurrence of hard inclusions – in terms of layers, boulders and other forms – has revealed a consistent failure of BWE-s to meet this challenge. This paper, inspired by the research project RFCR-CT-2015-00003-BEWEXMIN „Bucket wheel excavators operating under difficult mining conditions including un-mineable inclusions and geological structures with excessive mining resistance” deals with preliminary considerations and results that aim to contribute to solving this problem.

scholarly journals Possibilities of Utilization of Aggregates and Extractive Waste from Hard Coal Mining at Janina Mine in the Process of Reclamation of Open-pit Mines

2016 ◽  
Vol 32 (3) ◽  
pp. 111-134 ◽  
Author(s):  
Beata Klojzy-Karczmarczyk ◽  
Janusz Mazurek ◽  
Krzysztof Paw
Keyword(s):  
Coal Mining ◽  
Sulfur Content ◽  
Water Environment ◽  
Total Content ◽  
Waste Rock ◽  
Open Pit ◽  
Chemical Analyses ◽  
Open Pit Mines ◽  
Physical And Chemical ◽  
Soil And Water

AbstractIn recent years, the economic importance of gangue mined during coal production has changed and it is currently treated more and more often not as waste but as a source of mineral resources for economic use. The overriding objective throughout the reclamation process of open-pit mines associated with the utilization of external material is to make sure that the placement of waste rock on the surface does not cause damage to the environment. The paper presents results of the diagnosis and evaluation of the possibility of filling open-pit mine workings with mining waste or other materials, for example aggregates produced on the basis of gangue, originating in the Janina Mine mining plant (a subsidiary of TAURON Wydobycie S.A.). The study involved aggregate or coal silts from dewatering on the filter presses. The evaluation refers to the legal aspects and takes the requirements of pollution prevention into account, with a particular emphasis on soil, surface water and groundwater. The analysis of the potential impact on the soil and water environment of the project involving reclamation of the open-pit excavation with the use of minerals or waste from coal mining was carried out based on a study of the total content of sulfur and other elements in the samples pierwiastków (As, Cd, Co, Cr, Cu, Hg, Mo, Ni, Pb, V and Zn), as well as of the leaching of components. Moreover, an examination of the coefficient of permeability and porosity was conducted, which allowed the suitability of the material for the construction of insulating layers to be determined. The physical and chemical analyses were conducted on a total of over a dozen samples of waste rock, a byproduct of the enrichment of coal in the Janina Mine plant. The specific studies of the total sulfur content were conducted for the 16 primary samples scattered into 15 fractions each. Moreover, the so-called secondary samples were created, meaning that fine fractions of less than 20 mm and less than 10 mm were rejected. The total content of the selected components was examined for such crafted samples and their concentrations were determined in the leachable form (batch test 1:10). In the case of use of waste rock as an aggregate for quarry reclamation, a comparative analysis was applied to the legal requirements assigned to the mining waste and the quality of soil and water environment. Based on the conducted studies, it has been concluded that the coal silts (filter cakes) are characterized by good insulating properties and can be used for waterproofing objects, especially in the industrial, communications and mining areas. However, coal silts do not meet the quality requirements, mainly due to their slightly increased chlorides content, in addition to being a waste, which in some cases limits the possibility of their use. The best quality parameters were found for the gangue from the Janina Mine (on the basis of which aggregates are manufactured), but deprived of fine fractions. Physical and chemical analyses of the total content of elements in the secondary samples showed that the obtained values are within the allowable ranges determined by appropriate regulations for the vast majority of samples. The limit of 1% was assumed for the sulfur content. The conducted research on the leaching of pollutants indicates that the tested samples do not introduce contaminants exceeding the limit values for the analyzed metals and sulfates. Only single exceedances of the analyzed parameters are observed. The test results allow to conclude that it is possible to obtain a useful product that meets the requirements of environmental protection, but only after the rejection of fine fractions of the waste material.

Sign in / Sign up

Export Citation Format

Share Document