Figure - available from: Geofluids
This content is subject to copyright. Terms and conditions apply.
Source publication
This paper is aimed at solving the technical problems such as low recovery ratio and frequent disasters in steeply inclined and extrathick coal seams at residual high sectional coal pillar. It takes the Wudong Coal Mine as an engineering background, a typical mine of steeply inclined and extrathick coal seams; the structural features of the top-coa...
Similar publications
This study analyzes the main causes of accidents in the period of coal mine shaft construction and the shortage of the existing safety monitoring technology, puts forward the intelligent safety monitoring robot technology based on shaft construction, and deeply investigates the functions that the safety monitoring robot should have. Besides, the re...
Citations
... In LTCC applications, in horizontal and near-horizontal coal seams, the face is formed along the slope of the coal seam (Unver and Yasitli 2006;Tarakki et al. 2016), while in steeply inclined thick coal seams, depending on the thickness of the coal seam, the face is formed along the horizontal thickness of the coal seam or along the slope of the coal seam Fig. 2 shows coal seam thicknesses and slopes in LTCC applications applied in coal mines around the world (Rak et al. 2020;Li et al. 2017;Lv et al. 2021;Cao et al. 2020;Chi et al. 2019;Chi et al. 2021;Cui et al. 2019;Feng et al. 2018;Guney 1967;Guo et al. 2017;Huang et al. 2020;Lai et al. 2014;Li and Cheng 2015;Quang 2010;Senkal et al. 1988;Sun 2020;Wang et al.2019b;Xie and Zhao 2009;Yang et al. 2019;Yang et al. 2020;Yucekent 1979). ...
In this study, the effects of coal seam slope, caving height and top coal drawing interval parameters on longwall top coal caving (LTCC) efficiency in LTCC applied in horizontal and near-horizontal thick coal seams were investigated. In addition to these researches, in the study, the relationship between top coal loss and rock mixture ratio, which are important disadvantages of LTCC, was evaluated and the importance of these parameters for LTCC was emphasized by determining the critical top coal loss and critical rock mixture ratio. As a research method, physical models that are effectively used in researching caving mechanism problems were used and a 2-dimensional physical model was developed for the study. The development processes of the physical model, test material selection processes and the suitability of the physical model are explained in detail in the study. A total of 47 physical model tests were carried out in the research. Test results showed that the caving height and top coal drawing interval are effective on the rock mixture ratio, the top coal drawing interval is effective on the top coal loss, and the caving height and coal seam slope are effective on the amount of top coal drawing. In addition, the study results showed that the relationship between top coal loss and rock mixture ratio is an important relationship for LTCC efficiency under all conditions, and the importance of critical top coal loss and critical rock mixture ratio for LTCC was revealed.
... The high-reach single-pass longwall used in Australia has been successful, but the cutting height is limited to less than 4.8 m with current equipment. To increase the recovery of Australian thick seam reserves, the LTCC mining technology is providing an alternative solution to economic underground thick seam mining in Australia [24][25][26][27]. The conceptual model of longwall top coal caving (LTCC) is shown in Figure 4. ...
In underground coal mining, the working environment is completely enclosed by the geologic medium, which consists of the coal seam and overlying and underlying strata. Depillaring is one of the most dangerous phases of underground coal mining. Even after centuries of experience in underground coal mining, there is no well-established depillaring method w.r.t existing geo-mining method. As far as fatal accidents are concerned, most of the fatal accidents occur mostly during depillaring operations. Method of extraction is one of the keys and underrated parameters, which plays an eminent role in successful depillaring in underground coal mining. This chapter highlights the underground coal mining methods and their impact on safety.
