Field trials of aquifer protection in longwall mining of shallow coal seams in China

Energy Technology Data Exchange (ETDEWEB)

Zhang, D.S.; Fan, G.W.; Liu, Y.D.; Ma, L.Q. [State Key Laboratory of Coal Resource & Mine Safety, Xuzhou (China)

2010-09-15

The large-scale mining of shallow coal seams has a significant impact on the overlying aquifers and surface ecological environment. To protect the aquifers and maximize the coal resource recovery, field trials were undertaken during the operation of the LW32201 in Bulianta coal mine, Shendong, China. With a severely weathered rock (SWR) layer and two key strata (KS) in the overlying strata, aquifer protection in longwall mining (APLM) relies mainly on the rapid advance. In some localized zones, special measures should be taken to achieve the APLM, including lowering mining height, backfill and slurry injection. To further understand the mechanism and applicable conditions of the APLM and validate the effectiveness of the APLM, variation of the water table in the aquifer was observed as the longwall face passed through the zone. This paper also discusses the mechanism and basic requirements of the APLM and the relationship between the fall of the water table and the surface subsidence. The results of the field trials indicated that APLM in shallow coal seams could be successful under suitable conditions.

Hydrogeologic impacts of underground (Longwall) mining in the Illinois basin

International Nuclear Information System (INIS)

Booth, C.J.

1992-01-01

This paper reports that hydrogeological impacts of active longwall mining were studied at two sites in Illinois. At the site with the more transmissive sandstone aquifer, aquifer permeabilities increased an order of magnitude due to subsidence. Piezometric levels declined with subsidence due to increased porosity, and ahead of mining due to a transmitted drawdown. Levels recovered rapidly at first and fully over two years. At the site with the less transmissive aquifer, impacts were similar except that recovery has been limited. Local aquifer enhancement through increased yield can occur, but only where the aquifer is transmissive enough for recovery

Longwall face recovery operations at Mine 26 of the Old Ben Coal Company, Benton, Illinois, USA

Energy Technology Data Exchange (ETDEWEB)

Monks, W R; Hodgkinson, D; Ferris, W

1985-02-01

The paper describes a longwall face recovery (salvage) operation witnessed by National Coal Board Western Areas personnel at No. 26 Mine of the Old Ben Coal Company in Venton, Illinois. A brief review is made of the company and No. 26 Mine, and followed by a description of the longwall face salvage operations detailing the face equipment, preparation work, salvage equipment used, the method of operation and the results obtained. Particular reference is made to the successful use of Free Steered Vehicles (FSVs) for salvaging equipment and the use of roof bolts for the primary support of the face line. Finally, a number of conclusions are made which lead to firm recommendations for UK adoption.

30 CFR 75.813 - High-voltage longwalls; scope.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false High-voltage longwalls; scope. 75.813 Section... AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution High-Voltage Longwalls § 75.813 High-voltage longwalls; scope. Sections 75.814 through 75.822 of this...

Application of underground microseismic monitoring for ground failure and secure longwall coal mining operation: A case study in an Indian mine

Science.gov (United States)

Ghosh, G. K.; Sivakumar, C.

2018-03-01

Longwall mining technique has been widely used around the globe due to its safe mining process. However, mining operations are suspended when various problems arise like collapse of roof falls, cracks and fractures propagation in the roof and complexity in roof strata behaviors. To overcome these colossal problems, an underground real time microseismic monitoring technique has been implemented in the working panel-P2 in the Rajendra longwall underground coal mine at South Eastern Coalfields Limited (SECL), India. The target coal seams appears at the panel P-2 within a depth of 70 m to 76 m. In this process, 10 to 15 uniaxial geophones were placed inside a borehole at depth range of 40 m to 60 m located over the working panel-P2 with high rock quality designation value for better seismic signal. Various microseismic events were recorded with magnitude ranging from -5 to 2 in the Richter scale. The time-series processing was carried out to get various seismic parameters like activity rate, potential energy, viscosity rate, seismic moment, energy index, apparent volume and potential energy with respect to time. The used of these parameters helped tracing the events, understanding crack and fractures propagation and locating both high and low stress distribution zones prior to roof fall occurrence. In most of the cases, the events were divided into three stage processes: initial or preliminary, middle or building, and final or falling. The results of this study reveal that underground microseismic monitoring provides sufficient prior information of underground weighting events. The information gathered during the study was conveyed to the mining personnel in advance prior to roof fall event. This permits to take appropriate action for safer mining operations and risk reduction during longwall operation.

The evolution of longwall face support in the Mines de Potasse d'Alsace

Energy Technology Data Exchange (ETDEWEB)

Deffontaine, P

1978-06-01

In the Alsace (France) potash mines, caved longwalls were supported up to 1949 by timber chocks and friction or hydraulic props. Powered advancing support by chock type supports appeared in 1950 when shearers were put into service. Discloses evolution, progress, and costing of advancing supports in 1978. (In French)

Longwall automation 2

Energy Technology Data Exchange (ETDEWEB)

David Hainsworth; David Reid; Con Caris; J.C. Ralston; C.O. Hargrave; Ron McPhee; I.N. Hutchinson; A. Strange; C. Wesner [CSIRO (Australia)

2008-05-15

This report covers a nominal two-year extension to the Major Longwall Automation Project (C10100). Production standard implementation of Longwall Automation Steering Committee (LASC) automation systems has been achieved at Beltana and Broadmeadow mines. The systems are now used on a 24/7 basis and have provided production benefits to the mines. The LASC Information System (LIS) has been updated and has been implemented successfully in the IT environment of major coal mining houses. This enables 3D visualisation of the longwall environment and equipment to be accessed on line. A simulator has been specified and a prototype system is now ready for implementation. The Shearer Position Measurement System (SPMS) has been upgraded to a modular commercial production standard hardware solution.A compact hardware solution for visual face monitoring has been developed, an approved enclosure for a thermal infrared camera has been produced and software for providing horizon control through faulted conditions has been delivered. The incorporation of the LASC Cut Model information into OEM horizon control algorithms has been bench and underground tested. A prototype system for shield convergence monitoring has been produced and studies to identify techniques for coal flow optimisation and void monitoring have been carried out. Liaison with equipment manufacturers has been maintained and technology delivery mechanisms for LASC hardware and software have been established.

Analysis and Assessment of Parameters Shaping Methane Hazard in Longwall Areas

Directory of Open Access Journals (Sweden)

Eugeniusz Krause

2013-01-01

Full Text Available Increasing coal production concentration and mining in coal seams of high methane content contribute to its growing emission to longwall areas. In this paper, analysis of survey data concerning the assessment of parameters that influence the level of methane hazard in mining areas is presented. The survey was conducted with experts on ventilation and methane hazard in coal mines. The parameters which influence methane hazard in longwall areas were assigned specific weights (numerical values. The summary will show which of the assessed parameters have a strong, or weak, influence on methane hazard in longwall areas close to coal seams of high methane content.

Development of oxidation heat of the coal left in the mined-out area of a longwall face: Modelling using the fluent software

Directory of Open Access Journals (Sweden)

Taraba B.

2008-01-01

Full Text Available A commercial CFD software program, Fluent, was used to study oxidation processes in the longwall mined-out (gob area. A three-dimensional model of the gob area with an advancing coal face has been developed. For the model, typical oxidation behavior of a bituminous coal from the Ostrava-Karviná District was incorporated as resulted from laboratory investigations. The longwall gob area was designed on the basis of the actual longwall face district. Detailed measurements in the district then enabled re-verification of the model outputs with actual data in situ. The main attention was paid to modelling the effect of grain size of the coal left in the mined-out area on the oxidation heat and gases evolution. Numerical simulations confirmed the existence of an 'optimal' zone for intense development of the spontaneous heating process in the gob area.

An influence function method based subsidence prediction program for longwall mining operations in inclined coal seams

Energy Technology Data Exchange (ETDEWEB)

Yi Luo; Jian-wei Cheng [West Virginia University, Morgantown, WV (United States). Department of Mining Engineering

2009-09-15

The distribution of the final surface subsidence basin induced by longwall operations in inclined coal seam could be significantly different from that in flat coal seam and demands special prediction methods. Though many empirical prediction methods have been developed, these methods are inflexible for varying geological and mining conditions. An influence function method has been developed to take the advantage of its fundamentally sound nature and flexibility. In developing this method, significant modifications have been made to the original Knothe function to produce an asymmetrical influence function. The empirical equations for final subsidence parameters derived from US subsidence data and Chinese empirical values have been incorporated into the mathematical models to improve the prediction accuracy. A corresponding computer program is developed. A number of subsidence cases for longwall mining operations in coal seams with varying inclination angles have been used to demonstrate the applicability of the developed subsidence prediction model. 9 refs., 8 figs.

Thin Spray-on Liner - a potential application. Demonstrated at a longwall installation on Dendrobium mine

Energy Technology Data Exchange (ETDEWEB)

Byrnes, Roger [BHP Billiton, NSW (Australia). Dendrobium Mine; Martin, Philip [BASF AG Australia (Australia). BASF-CC Australia Ltd' s

2008-08-21

The paper describes a potential application of a Thin Spray-on Liner, on a longwall installation in Australia. The BHPBilliton mine, Dendrobium, is a relatively new mine in the Southern New South Wales coalfields, near to Wollongong. Normal installation and start-up operations for a new longwall face is to completely rock bolt and mesh the face. The operations use plastic/glassfibre cutable rock bolts, with steel/plastic mesh to prevent spalling. The biggest problem on face start up is the sheets of steel or plastic mesh getting wrapped around the shearer disc, which requires time consuming additional work removing the mesh. BASF Construction Chemicals Australia Pty Ltd's Underground Construction group, (UGC), proposed the use of Masterseal 845A, a fast sprayable cementitious/polymer membrane material that could be trialed and used to replace the steel mesh, as a surface support in unison with the conventional cutable rock bolts. The application took 12 h spraying to cover the 240 m long face line which averaged about 3.3 m high. The product was sprayed between 3.5 m to 4 mm thick, and according to the mine operators was at least three times quicker than mesh installation, not withstanding the savings in transport of the awkward bundles of mesh. In conclusion the Thin Spray-on Liner (TSL) performed adequately and achieved it's objective in this installation at Dendrobium mine. (orig.)

Risk Analysis and Prediction of Floor Failure Mechanisms at Longwall Face in Parvadeh-I Coal Mine using Rock Engineering System (RES)

Science.gov (United States)

Aghababaei, Sajjad; Saeedi, Gholamreza; Jalalifar, Hossein

2016-05-01

The floor failure at longwall face decreases productivity and safety, increases operation costs, and causes other serious problems. In Parvadeh-I coal mine, the timber is used to prevent the puncture of powered support base into the floor. In this paper, a rock engineering system (RES)-based model is presented to evaluate the risk of floor failure mechanisms at the longwall face of E 2 and W 1 panels. The presented model is used to determine the most probable floor failure mechanism, effective factors, damaged regions and remedial actions. From the analyzed results, it is found that soft floor failure is dominant in the floor failure mechanism at Parvadeh-I coal mine. The average of vulnerability index (VI) for soft, buckling and compressive floor failure mechanisms was estimated equal to 52, 43 and 30 for both panels, respectively. By determining the critical VI for soft floor failure mechanism equal to 54, the percentage of regions with VIs beyond the critical VI in E 2 and W 1 panels is equal to 65.5 and 30, respectively. The percentage of damaged regions showed that the excess amount of used timber to prevent the puncture of weak floor below the powered support base is equal to 4,180,739 kg. RES outputs and analyzed results showed that setting and yielding load of powered supports, length of face, existent water at face, geometry of powered supports, changing the cutting pattern at longwall face and limiting the panels to damaged regions with supercritical VIs could be considered to control the soft floor failure in this mine. The results of this research could be used as a useful tool to identify the damaged regions prior to mining operation at longwall panel for the same conditions.

Stress analysis of longwall top coal caving

Energy Technology Data Exchange (ETDEWEB)

Alehossein, H.; Poulsen, B.A. [CSIRO Exploration & Mining, Brisbane, Qld. (Australia)

2010-01-15

Longwall top coal caving (LTCC) is a relatively new method of mining thick coal seams that is currently achieving high productivity and efficiency. The technique is similar to traditional longwall mining in that a cutting head slices coal from the lower section of the coal seam onto a conveyor belt installed in front of the hydraulic support near the cutting face. In modern LTCC an additional rear conveyor belt is located behind the support, to which the flow of the caved coal from the upper part of the seam can be controlled by a moveable flipper attached to the canopy of the support. The mining method relies on the fracturing of the top coal by the front abutment pressure to achieve satisfactory caving into the rear conveyor. This paper develops a yield and caveability criterion based on in situ conditions in the top coal in advance of the mining face (yield) and behind the supports (caveability). Yielding and caving effects are combined into one single number called caving number (CN), which is the multiplication result of caving factor (CF) and yield factor (YF). Analytical derivations are based on in situ stress conditions, Mohr-Coulomb and/or Hoek-Brown rock failure criteria and an on-associated elastoplastic strain softening material behaviour. The yield and caveability criteria are in agreement with results from both numerical studies and mine data. The caving number is normalised to mining conditions of a reference Chinese mine (LMX mine) and is used to assess LTCC performance at fourteen other Chinese working longwalls that have had varying success with the LTCC technology. As a predictive model, results of this analytical/numerical study are useful to assess the potential success of caving in new LTCC operations and in different mining conditions.

Numerical Simulation of Aerogasdynamics Processes in A Longwall Panel for Estimation of Spontaneous Combustion Hazards

Science.gov (United States)

Meshkov, Sergey; Sidorenko, Andrey

2017-11-01

The relevance of a solution of the problem of endogenous fire safety in seams liable to self-ignition is shown. The possibilities of numerical methods of researches of gasdynamic processes are considered. The analysis of methodical approaches with the purpose to create models and carry out numerical researches of aerogasdynamic processes in longwall panels of gas mines is made. Parameters of the gob for longwall mining are considered. The significant influence of geological and mining conditions of conducting mining operations on distribution of air streams on longwall panels and effective management of gas emission is shown. The aerogasdynamic model of longwall panels for further research of influence of parameters of ventilation and properties of gob is presented. The results of numerical researches including distribution of air streams, fields of concentration of methane and oxygen at application of various schemes of airing for conditions of perspective mines of the Pechora basin and Kuzbass are given. Recommendations for increase of efficiency of the coal seams mining liable to selfignition are made. The directions of further researches are defined.

Evaluate fundamental approaches to longwall dust control. Phase III report

Energy Technology Data Exchange (ETDEWEB)

Babbitt, C.; Bartlett, P.; Kelly, J.; Ludlow, J.; Mangolds, A.; Rajan, S.; Ruggieri, S.; Varga, E.

1984-03-31

The overall objective of the contract is to evaluate the effectiveness of available dust control technology for double-drum shearer longwall sections in a coordinated, systematic program at a few longwall test sections and to make the results available to the entire coal mining industry. This program is investigating nine different dust control techniques. These nine subprograms encompass a broad range of dust control measures ranging from administrative controls to new hardware. They span not only presently employed methods but also those recently adopted in the United States and those proposed for the future. This report documents the Phase III effort on each of the subprograms. For clarity, the report is divided in sections by subprogram as follows: Section 2, Subprogram A - passive barriers/spray air movers for dust control; Section 3, Subprogram B - practical aspects of deep cutting; Section 4, Subprogram C - stage loader dust control; Section 5, Subprogram D - longwall automation technology; Section 6, Subprogram E - longwall application of ventilation curtains; Section 7, Subprogram F - reversed drum rotation; Section 8, Subprogram G - reduction of shield generated dust; Section 9, Subprogram H - air canopies for longwalls; and Section 10, Subprogram I - mining practices. 43 figures, 11 tables.

Numerical modeling for longwall pillar design: a case study from a typical longwall panel in China

Science.gov (United States)

Zhang, Guangchao; Liang, Saijiang; Tan, Yunliang; Xie, Fuxing; Chen, Shaojie; Jia, Hongguo

2018-02-01

This paper presents a new numerical modeling procedure and design principle for longwall pillar design with the assistance of numerical simulation of FLAC3D. A coal mine located in Yanzhou city, Shandong Province, China, was selected for this case study. A meticulously validated numerical model was developed to investigate the stress changes across the longwall pillar with various sizes. In order to improve the reliability of the numerical modeling, a calibration procedure is undertaken to match the Salamon and Munro pillar strength formula for the coal pillar, while a similar calibration procedure is used to estimate the stress-strain response of a gob. The model results demonstrated that when the coal pillar width was 7-8 m, most of the vertical load was carried by the panel rib, whilst the gateroad was overall in a relatively low stress environment and could keep its stability with proper supports. Thus, the rational longwall pillar width was set as 8 m and the field monitoring results confirmed the feasibility of this pillar size. The proposed numerical simulation procedure and design principle presented in this study could be a viable alternative approach for longwall pillar design for other similar projects.

Three-dimensional time-lapse velocity tomography of an underground longwall panel

Energy Technology Data Exchange (ETDEWEB)

Luxbacher, K.; Westman, E.; Swanson, P.; Karfakis, M. [Virginia Tech., Blacksburg, VA (United States). Dept. of Mining & Minerals Engineering

2008-06-15

Three-dimensional velocity tomograms were generated to image the stress redistribution around an underground coal longwall panel to produce a better understanding of the mechanisms that lead to ground failure, especially rockbursts. Mining-induced microseismic events provided passive sources for the three-dimensional velocity tomography. Surface-mounted geophones monitored microseismic activity for 18 days. Eighteen tomograms were generated and high-velocity regions correlated with high abutment stresses predicted by numerical modeling. Additionally, the high-velocity regions were observed to redistribute as the longwall face retreated, indicating that velocity tomography may be an appropriate technology for monitoring stress redistribution in underground mines.

Underground coal mining technology - the future

Energy Technology Data Exchange (ETDEWEB)

Lama, R P [Kembla Coal and Coke Pty Limited, Wollongong, NSW (Australia)

1989-01-01

Discusses development of underground coal mining in Australia in the last four decades. The following aspects are reviewed: technology for underground mining (longwall mining, unidirectional cutting, bidirectional cutting, operation of more than one shearer on a working face, optimum dimensions of longwall blocks), longwall productivity (productivity increase will depend on increasing the availability factor of equipment, reducing failures due to human errors, organizational models, improving on-site decision making, improving monitoring, maintenance, planning and scheduling, concept of 'Transparent Mine'), roadway development systems (types of heading machines, standard systems for mine drivage and roof bolting and their productivity), size of coal mines, man and material transport systems (20,000-30,000 t/d from a single longwall face, mine shafts with a diameter 9-10 m), mine layout design (layout of longwall blocks, main intakes and returns situated in rock layers), mine environmental systems (ventilation systems, gas control), management, training and interpersonal relationships. Future coal mines will be developed with an integral capacity of 8-10 Mt/a from a single longwall operation with main development arteries placed in rocks. Development of gate roadways will require novel solutions with continuous cutting, loading and bolting. Information technology, with the concept of 'transparent mine', will form the backbone of decision making.

Large-Strain Monitoring Above a Longwall Coal Mine With GPS and Seismic Measurements

Science.gov (United States)

Swanson, P. L.; Andreatta, V.; Meertens, C. M.; Krahenbuhl, T.; Kenner, B.

2001-12-01

As part of an effort to evaluate continuous GPS measurements for use in mine safety studies, a joint GPS-seismic experiment was conducted at an underground longwall coal mine near Paonia, Colorado in June, 2001. Seismic and deformation signals were measured using prototype low-cost monitoring systems as a longwall panel was excavated 150 m beneath the site. Data from both seismic and GPS instruments were logged onto low-power PC-104 Linux computers which were networked using a wireless LAN. The seismic system under development at NIOSH/SRL is based on multiple distributed 8-channel 24-bit A/D converters. The GPS system uses a serial single-frequency (L1) receiver and UNAVCO's "Jstream" Java data logging software. For this experiment, a continuously operating dual-frequency GPS receiver was installed 2.4 km away to serve as a reference site. In addition to the continuously operating sites, 10 benchmarks were surveyed daily with short "rapid-static" occupations in order to provide greater spatial sampling. Two single-frequency sites were located 35 meters apart on a relatively steep north-facing slope. As mining progressed from the east, net displacements of 1.2 meters to the north and 1.65 meters of subsidence were observed over a period of 6 days. The east component exhibited up to 0.45 meters of eastward displacement (toward the excavation) followed by reverse movement to the west. This cycle, observed approximately two days earlier at the eastern L1 site, is consistent with a change in surface strain from tension to compression as the excavation front passed underneath. As this strain "wave" propagated across the field site, surface deformation underwent a cycle of tension crack nucleation, crack opening (up to 15 cm normal displacements), subsequent crack closure, and production of low-angle-thrust compressional deformation features. Analysis of seismic results, surface deformation, and additional survey results are presented.

Numerical modelling of surface subsidence arising from longwall mining of steeply inclined coal seams

Energy Technology Data Exchange (ETDEWEB)

Nejad, M.A.; Reddish, D.J. [University of Nottingham, Nottingham (United Kingdom). School of Chemical, Environmental and Mining Engineering

1998-12-31

The paper presents results from and the methodology of a numerical modelling investigation into the surface ground movements above longwall mining of inclined and steep seams with varying panel configurations. A modelling approach was developed using a finite difference numercial model Fast Lagrangian Analysis of Continua (FLAC). On the basis of this methodology, representative surface subsidence profiles were simulated and the results of simulations were validated against the UK data using the Subsidence Engineer`s Handbook (SEH) and influence function methods. Furthermore, the proposed methodology was applied to two UK case histories for validation purposes. 15 refs., 7 figs., 3 tabs.

Numerical analysis of control of hard roof's stepped cantilever structure for longwall mining with sublevel caving

Energy Technology Data Exchange (ETDEWEB)

Wei, J.; Jin, Z.; Tang, Y. [Taiyuan University of Technology, Taiyuan (China)

2002-12-01

Based on the field monitoring and simulation test of strata movement, the hard roof's stepped cantilever structure and its mechanics model are presented. The finite element method is used to analyse the effect of hard coal cracking under the abutment pressure of hard roof, so the rational pre-treatment span of hard roof is determined, and the rational working resistance of support is selected also. According to the mechanics model, the transient balance conditions of the hard roof's stepped cantilever structure are studied, and the support-rock relation is theoretically explained. As a result, the basic theory and technique of surrounding rocks control for fully mechanised longwall mining with sub-level caving is formed under the hard roof and hard coal conditions, and the hard roof is effectively controlled not only to protect the working face but also to promote the caving of hard top-coal to increase the recovery rate of coal, thus to realise safe and highly efficient and productive fully mechanised longwall mining with sub-level caving in extra-thick seam. Finally, the successfully practice of hard roof control in 8914 and 8911 working face is presented in this paper. 10 refs., 5 figs., 4 tabs.

Foam property tests to evaluate the potential for longwall shield dust control.

Science.gov (United States)

Reed, W R; Beck, T W; Zheng, Y; Klima, S; Driscoll, J

2018-01-01

Tests were conducted to determine properties of four foam agents for their potential use in longwall mining dust control. Foam has been tried in underground mining in the past for dust control and is currently being reconsidered for use in underground coal longwall operations in order to help those operations comply with the Mine Safety and Health Administration's lower coal mine respirable dust standard of 1.5 mg/m 3 . Foams were generated using two different methods. One method used compressed air and water pressure to generate foam, while the other method used low-pressure air generated by a blower and water pressure using a foam generator developed by the U.S. National Institute for Occupational Safety and Health. Foam property tests, consisting of a foam expansion ratio test and a water drainage test, were conducted to classify foams. Compressed-air-generated foams tended to have low expansion ratios, from 10 to 19, with high water drainage. Blower-air-generated foams had higher foam expansion ratios, from 30 to 60, with lower water drainage. Foams produced within these ranges of expansion ratios are stable and potentially suitable for dust control. The test results eliminated two foam agents for future testing because they had poor expansion ratios. The remaining two foam agents seem to have properties adequate for dust control. These material property tests can be used to classify foams for their potential use in longwall mining dust control.

10th international conference on ground control in mining - proceedings

International Nuclear Information System (INIS)

Peng, S.S.

1991-01-01

36 papers are presented covering topics that include longwall pillar design, assessment of underground structural design, load and convergence measurements in longwall faces, shield strata interaction, longwall shield recovery, roof control in longwall mining, anchor resin system, thrust bolting, roof bolts, cable slings, roof support in retreat mining, coal bump prediction, delineation of abandoned workings, stability of coal mine openings, mining under rivers, rock strength determination, subsidence prediction and measurement, drag picks, measuring roof convergence, and finite element modelling of subsidence

Algorithm of probabilistic assessment of fully-mechanized longwall downtime

Science.gov (United States)

Domrachev, A. N.; Rib, S. V.; Govorukhin, Yu M.; Krivopalov, V. G.

2017-09-01

The problem of increasing the load on a long fully-mechanized longwall has several aspects, one of which is the improvement of efficiency in using available stoping equipment due to the increase in coefficient of the machine operating time of a shearer and other mining machines that form an integral part of the longwall set of equipment. The task of predicting the reliability indicators of stoping equipment is solved by the statistical evaluation of parameters of downtime exponential distribution and failure recovery. It is more difficult to solve the problems of downtime accounting in case of accidents in the face workings and, despite the statistical data on accidents in mine workings, no solution has been found to date. The authors have proposed a variant of probability assessment of workings caving using Poisson distribution and the duration of their restoration using normal distribution. The above results confirm the possibility of implementing the approach proposed by the authors.

Experimental study on foam coverage on simulated longwall roof

Science.gov (United States)

Reed, W.R.; Zheng, Y.; Klima, S.; Shahan, M.R.; Beck, T.W.

2018-01-01

Testing was conducted to determine the ability of foam to maintain roof coverage in a simulated longwall mining environment. Approximately 27 percent of respirable coal mine dust can be attributed to longwall shield movement, and developing controls for this dust source has been difficult. The application of foam is a possible dust control method for this source. Laboratory testing of two foam agents was conducted to determine the ability of the foam to adhere to a simulated longwall face roof surface. Two different foam generation methods were used: compressed air and blower air. Using a new imaging technology, image processing and analysis utilizing ImageJ software produced quantifiable results of foam roof coverage. For compressed air foam in 3.3 m/s (650 fpm) ventilation, 98 percent of agent A was intact while 95 percent of agent B was intact on the roof at three minutes after application. At 30 minutes after application, 94 percent of agent A was intact while only 20 percent of agent B remained. For blower air in 3.3 m/s (650 fpm) ventilation, the results were dependent upon nozzle type. Three different nozzles were tested. At 30 min after application, 74 to 92 percent of foam agent A remained, while 3 to 50 percent of foam agent B remained. Compressed air foam seems to remain intact for longer durations and is easier to apply than blower air foam. However, more water drained from the foam when using compressed air foam, which demonstrates that blower air foam retains more water at the roof surface. Agent A seemed to be the better performer as far as roof application is concerned. This testing demonstrates that roof application of foam is feasible and is able to withstand a typical face ventilation velocity, establishing this technique’s potential for longwall shield dust control. PMID:29563765

Dimensionless model to determine spontaneous combustion danger zone in the longwall gob

Institute of Scientific and Technical Information of China (English)

ZHANG Xin-hai; DENG Jun; WEN Hu

2011-01-01

According to spontaneous combustion propensity,the longwall gob is divided into three zones,including heat dissipation zone,self-heating zone and the choking zone.Only in the self-heating zone can temperature of coal rise due to oxidation.Studying the distribution of the “Three Zones” in gob is important for predicting and preventing spontaneous combustion in coalmine.In normal mining operations,temperature of coal is roughly constant.The process of mass transfer in the gob is considered to be steady.Based on mass conservation,gas species conservation,darcy' s law,Ficks law of diffusion and coal oxidation 1-grade reaction rule,governing equation for air leakage intensity and species concentration are deduced.With critical value of coal spontaneous combustion and the size of longwall workface as basic dimension,a dimensionless steady coupled model of air flow diffusion and chemical reaction in loose coal of Fully Mechanized Top-Coal Caving Mining Workface (FMTCCMW) is setup.By solving the model numerically,regulation of three zones' distribution and spontaneous combustion in the gob can be obtained.The results can be easily popularized to prediction of spontaneous combustion in other coalmines' longwall gob.

Electromechanical dynamic analysis for the drum driving system of the long-wall shearer

Directory of Open Access Journals (Sweden)

Changzhao Liu

2015-10-01

Full Text Available The drum driving system is one of the weakest parts of the long-wall shearer, and some methods are also needed to monitor and control the long-wall shearer to adapt to the important trend of unmanned operation in future mining systems. Therefore, it is essential to conduct an electromechanical dynamic analysis for the drum driving system of the long-wall shearer. First, a torsional dynamic model of planetary gears is proposed which is convenient to be connected to the electric motor model for electromechanical dynamic analysis. Next, an electromechanical dynamic model for the drum driving system is constructed including the electric motor, the gear transmission system, and the drum. Then, the electromechanical dynamic characteristics are simulated when the shock loads are acted on the drum driving system. Finally, some advices are proposed for improving the reliability, monitoring the operating state, and choosing the control signals of the long-wall shearer based on the simulation.

Economical Optimization of the Mechanized Longwall Faces with Top Coal Caving Mining, In Horizontal Slices

Science.gov (United States)

Onica, Ilie; Mihăilescu, Viorel; Andrioni, Felicia

2016-09-01

To increase the economic and technical performances of the Jiu Valley hard coal mines, the top coal caving, in horizontal slices, mining methods (Bourbaki methods) were introduced, adapted to the local geo-mining conditions. This mining was successfully experimented by using classical technology, using the individual supports and coal blasting. In the future, it is planned to adopt the mechanized technology, with frame supports and shearers. The mechanized longwall faces with top coal caving mining, in horizontal slices, of coal seam no. 3 could be efficient only if the sizes of the top coal height and the panel length determine a minimum cost of production. Therefore, the goal of this paper is the optimization of these parameters, from a technical and economic point of view, taking into account the general model of the cost function, at the panel level. For that, it was necessary to make a certain sequence of analysis involving: technological unit establishment, purpose function and optimizing model. Thus, there attaining to the mathematical model of the unit cost, after determination of all the individual calculation articles, regarding the preparatory workings, coal face equipments, materials, energy, workforce, etc. Because of the complexity of the obtained technical and economic model, to determine the optimum sizes of the panel length and top coal height, it was necessary to archive a sensitivity analysis of the unit cost function to the main parameters implied into this mathematical model.

Development trends in mining technologies. [Poland

Energy Technology Data Exchange (ETDEWEB)

Sikora, W

1983-01-01

Research programs on underground black coal mining in Poland are discussed. It is assumed that no major technology changes will take place by the year 2000. Second generation of mining technologies will be used after the year 2000. The following technologies of the second generation are discussed: in-situ gasification, chemical coal disintegration, manless hydraulic mining with hydraulic transport. Research programs on technologies of the second generation should guarantee their commercial and economic use by the year 2000. The following targets for research programs aimed at increasing productivity, reducing mining cost, reducing labor and increasing safety in mining, covering the next 2 decades are comparatively evaluated: increasing advance rate of longwall faces, increasing machine time of integrated face systems by at least 20%, improving design of powered supports for eliminating rock falls, development of heavy-duty face systems for longwall mining with hydraulic stowing, development of face systems for mining thick coal seams on their whole thickness, slice mining thick coal seams with artificial roofs, bidirectional longwall mining by shearer loaders, use of more elastic and reliable mining systems.

Third symposium on underground mining

Energy Technology Data Exchange (ETDEWEB)

None

1977-01-01

The Third Symposium on Underground Mining was held at the Kentucky Fair and Exposition Center, Louisville, KY, October 18--20, 1977. Thirty-one papers have been entered individually into EDB and ERA. The topics covered include mining system (longwall, shortwall, room and pillar, etc.), mining equipment (continuous miners, longwall equipment, supports, roof bolters, shaft excavation equipment, monitoring and control systems. Maintenance and rebuilding facilities, lighting systems, etc.), ventilation, noise abatement, economics, accidents (cost), dust control and on-line computer systems. (LTN)

Development of a time-dependent energy model to calculate the mining-induced stress over gates and pillars

Directory of Open Access Journals (Sweden)

Mohammad Rezaei

2015-06-01

Full Text Available Generally, longwall mining-induced stress results from the stress relaxation due to destressed zone that occurs above the mined panel. Knowledge of induced stress is very important for accurate design of adjacent gateroads and intervening pillars which helps to raise the safety and productivity of longwall mining operations. This study presents a novel time-dependent analytical model for determination of the longwall mining-induced stress and investigates the coefficient of stress concentration over adjacent gates and pillars. The model is developed based on the strain energy balance in longwall mining incorporated to a rheological constitutive model of caved materials with time-varying parameters. The study site is the Tabas coal mine of Iran. In the proposed model, height of destressed zone above the mined panel, total longwall mining-induced stress, abutment angle, induced vertical stress, and coefficient of stress concentration over neighboring gates and intervening pillars are calculated. To evaluate the effect of proposed model parameters on the coefficient of stress concentration due to longwall mining, sensitivity analysis is performed based on the field data and experimental constants. Also, the results of the proposed model are compared with those of existing models. The comparative results confirm a good agreement between the proposed model and the in situ measurements. According to the obtained results, it is concluded that the proposed model can be successfully used to calculate the longwall mining-induced stress. Therefore, the optimum design of gate supports and pillar dimensions would be attainable which helps to increase the mining efficiency.

Accuracy of forecast of mine tremors location

Energy Technology Data Exchange (ETDEWEB)

Jan Drzewieck [Central Mining Institute, Katowice (Poland)

2009-09-15

The Upper Silesian Coal Basin is one of the most active mining areas in the world in respect of seismicity. Underground mining in this area takes place in a special environment with a high degree of risk of unpredictable event occurrence. Especially dangerous are phenomena that occur during the extraction of deposits at great depths in the environment of compact rocks. Deep underground mining violates the balance of these rocks and induces dynamic phenomena at the longwall life (in terms of distance) referred to as mine tremors. The sources of these tremors are located in layers characterised by high strength, especially in thick sandstone strata occurring in the roof of the mined seam. In the paper a discussion is presented about the influence of mining intensity (longwall face speed) on the location of mine tremor sources, both in the direction of longwall life (in terms of distance) and towards the surface. The presented material has been prepared based on the results of tests and measurements carried out at the Central Mining Institute. 8 refs., 5 figs.

Modeling the effect of seal leakage on spontaneous heating in a longwall gob area

Energy Technology Data Exchange (ETDEWEB)

Smith, A.C.; Yuan, L. [National Inst. for Occupational Safety and Health, Pittsburgh, PA (United States). Office of Mine Safety and Health Research

2010-07-01

Three coal mines in the United States with a history of spontaneous combustion use a bleederless ventilation system as a control measure. In a bleederless system, one of the headgate entries is used as the tailgate entry of the succeeding panel and is isolated from the gob of the active panel by gob seals that are installed in the headgate entry as the face advances. An active longwall panel using a Y-type bleederless ventilation system was simulated in this study. As longwall mining progresses, some seals are known to leak. Computational fluid dynamics (CFD) simulations were performed to study the effect of seal leakage on spontaneous heating of coal in the longwall gob area. The simulation results showed that under typical bleederless ventilation conditions, the maximum temperature in the gob increased with an increase in leakage rate. The maximum temperature occurred at the headgate side corner at the back end of the panel. When only 1 or 2 seals were leaking, the maximum temperature occurred around the seal. The results demonstrate that complex interactions between pressure differential and gob permeability at different locations in the gob cause ventilation pathways. The interactions depend greatly on gob permeability and seal leakage rates. 8 refs., 1 tab., 14 figs.

Conventional approaches for assessment of caving behaviour and support requirement with regard to strata control experiences in longwall workings

Directory of Open Access Journals (Sweden)

G.S.P. Singh

2015-06-01

Full Text Available Effective control of roof strata is very important for trouble free operation and regular face advance in mechanised longwall workings. It is now technically possible to exploit coal seams in difficult geo-mining conditions with the help of newer innovations in longwall face machineries. A reliable assessment of caving behaviour and support capacity requirement helps in selecting supports of adequate capacity and making operational preparedness for timely and confident solution of impending problems. This paper reviews the mechanism of roof caving and the conventional approaches of caving behaviour and support requirement in the context of major strata control experiences gained worldwide. The review shows that a number of approaches are being used for advance prediction of caving behaviour and support capacity requirement in a variety of geo-mining conditions. The theoretical explanation of the mechanism of roof caving and the design function of roof supports have been worked out through staged development of approaches, their evaluation followed by their gradual modification and enrichment of synthesized findings. This process is still continuing with consistently improved understanding through growing field experiences in the larger domain of geo-mining conditions and state-of-art strata analysis and monitoring techniques. These attempts have contributed significantly to improving the level of understanding and reducing the gap of uncertainty in planning and design of longwall operation in a given geo-mining condition.

Tube bundle system studies at Signal Peak Energy Bull Mountains #1 Mine.

Science.gov (United States)

Zipf, R K; Ochsner, R; Krog, R; Marchewka, W; Valente, M; Jensen, R

2014-03-01

A tube bundle system (TBS) is a mechanical system for continuously drawing gas samples through tubes from multiple monitoring points located in an underground coal mine for analysis and display on the surface. The U.S. National Institute for Occupational Safety and Health (NIOSH), in collaboration with Signal Peak Energy (SPE), LLC, Bull Mountains No. 1 Mine, operated a TBS during mining of two bleederless, longwall panels. This paper describes the gas analysis data and its interpretation. As verified by the TBS, coal at the SPE mine tends to oxidize slowly. It was known that a reservoir of low-oxygen concentration atmosphere developed about 610 m (2,000 ft) behind the longwall face. A bleederless ventilation system facilitates formation of an inert atmosphere in this longwall gob and decreases the likelihood of spontaneous combustion. Connections of the mine atmosphere to the surface through subsidence cracks could allow airflow into the longwall gob, revive coal oxidation and increase spontaneous combustion risk. The atmospheric composition of the sealed areas was homogeneous, except in the immediate vicinity of suspected ingassing points. The TBS verified that gases within the partially sealed, bleederless longwall gob expanded into the longwall tailgate area when barometric pressure decreased. The concentration of carbon dioxide in the back return airflow at the longwall tailgate was observed to increase by a factor of three and possibly up to 10 times the typical background concentration of 0.5 to 1.0%, depending on the size of the longwall gob and the magnitude of barometric pressure decrease. TBS have the inherent disadvantage of slow response time due to travel time of the gas samples and sequential gas analyses. A TBS or similar continuous monitoring system could be beneficial in detecting and providing warning of potentially hazardous gas concentrations, if the slow response time of the system is always understood.

Selected problems of coal mining mechanization in the coal industry of Poland

Energy Technology Data Exchange (ETDEWEB)

Antoniak, J; Sikora, W [Politechnika Slaska, Gliwice (Poland)

1987-01-01

Discusses conditions for underground coal mining in Poland, types of equipment for coal cutting, mine haulage and strata control and development trends of mining technologies. In 1985, black coal output was 191.6 Mt; 85.3% came from longwall faces mined by sets of mining equipment (coal cutters, chain conveyors and powered supports). The average coal output per longwall face was 881 t/d, output per face mined by sets for mining equipment was 1,134 t/d. In 1985, 653 shearer loaders and 77 coal plows were used in Polish coal mines. Number of shearer loaders is increasing. Shearer loaders with chainless haulage system were safest and most economic. The shearer loaders were equipped with the POLTRAK chainless haulage system developed in Poland. Research programs concentrate on development of new mining equipment for thin seam mining, steep seam mining, longwall mining with hydraulic stowing, efficient strata control by powered or shield supports under conditions of increased stresses or rock burst hazards. 4 refs.

Coal mining equipment

International Nuclear Information System (INIS)

Stein, R.R.; Martin, T.W.

1991-01-01

The word in longwall components is big, and these larger components have price tags to match. The logic behind the greater investment is that it will yield high production rates and good uptime statistics. This is true in most cases. More important than single-shift tonnage records, average shift production continues to climb upwards. This paper reports on the quality, and more significantly, the quantity of service supplied for long-wall equipment, which has reached levels that would have been seen as unachievable when longwall mining was first introduced in the U.S. The school of thought then was that longwall would increase productivity in part by reducing the number of production units and thus reducing the number of personnel employed underground. The expectation of fewer employees turned out to be unrealistic. That was probably one reason that some early attempts to install longwall system looked more like failures than vision of the future

Improving the efficiency of longwall face recoveries by managing the geotechnical threats

Energy Technology Data Exchange (ETDEWEB)

David Hill; Rob Thomas [Strata Engineering (Australia)

2006-12-15

The project objective was to develop credible industry guidelines for the specification of effective ground control strategies, so as to minimise the likely geotechnical threats relating to the safety, operational costs and production delays associated with the recovery and relocation of a longwall face. The project commenced with an industry survey of longwall relocation practice. The resulting database covers issues such as the geotechnical environment, support practices and ground control experiences, including any difficulties encountered. Fieldwork aimed at geotechnical characterisation covered a range of environments in NSW and Queensland, drawing also on existing data from a number of mines. Longwall take-off monitoring data was obtained from 24 face recoveries across all the major coalfields. The fieldwork identified a number of critical features of the geotechnical environment, support design and mining geometry that have a pronounced impact on ground control during take-off. A cantilever model of roof behaviour at the take-off point was developed and validated by the data collected. The roof cantilever acts to transfer load to the solid abutment, the primary support element. Four parameters were identified as the main geotechnical hazards, namely: low roof competency (ie weak roof); an adverse weighting environment; geological structure; and horizontal stress concentrations at the gate ends (generally the maingate). Four aspects of the geometry and process were seen to be particularly significant, in terms of their impact on roof stability and the success of the overall operation, namely: the ability to maintain powered support resistance during bolt-up and take-off; the direction in which the powered supports are removed; the impact of take-off chutes; and the speed of the powered support removal process.

Thin seam mining

Energy Technology Data Exchange (ETDEWEB)

Sikora, W [Politechnika Slaska, Gliwice (Poland). Instytut Mechanizacji Gornictwa

1989-06-01

Discusses thin seam mining in Poland and its prospects. There were 194 working faces in coal seams to 1.5 m thick in Poland in 1988. Of them, 115 fell on faces with powered supports, 79 on faces with SHC-40 and Valent props; 108 shearer loaders and 45 coal plows were used for longwall mining of thin coal seams. Drilling and blasting was used to mine 21 working faces. Longwall faces in seams to 1.0 m thick gave 2.0% coal output, faces in coal seams 1.01-1.5 m thick gave 12.2% of daily coal output of underground mining. Structure of daily coal output of faces in thin seams was the following: 52 faces below 300 t/day, 42 from 301-500 t/day, 63 from 501 to 1,000 t/day, 17 faces above 1,000 t/day. Prospects for increasing coal output of faces in thin seams are discussed. 7 refs.

Coal mine subsidence

International Nuclear Information System (INIS)

Darmody, R.G.; Hetzler, R.T.; Simmons, F.W.

1992-01-01

Longwall coal mining in southern Illinois occurs beneath some of the best agricultural land in the U.S. This region is characterized by highly productive, nearly level, and somewhat poorly drained soils. Subsidence from longwall mining causes changes in surface topography which alters surface and subsurface hydrology. These changes can adversely affect agricultural land by creating wet or ponded areas that can be deleterious to crop production. While most subsided areas show little impact from subsidence, some areas experience total crop failure. Coal companies are required by law to mitigate subsidence damage to cropland. The objective of this paper is to test the effectiveness of mitigation in restoring grain yields to their pre-mined levels. The research was conducted on sites selected to represent conventional mitigation techniques on the predominate soils in the area. Corn (Zea mays L.) and soybean [Glycine max.(L.) Merr] yields in 1988, 1989, 1990, and 1991 from mitigated areas were compared to yields from nearby undisturbed areas

3D numerical modeling of longwall mining with top-coal caving

Energy Technology Data Exchange (ETDEWEB)

Yasitli, N.E.; Unver, B. [Hacettepe University, Ankara (Turkey). Dept. of Mining Engineering

2005-02-01

Top-coal caving is the key factor affecting the efficiency of production at thick-coal seams. During production of top coal by caving behind the face not only a significant amount of coal is lost in the goaf but the coal drawn by means of caving is diluted considerably with surrounding rock. Therefore, it is not possible to carry out an efficient production operation unless caving of top coal behind the face is optimized. In this paper, results of 3D modeling of the top-coal-caving mechanism by using the finite difference code FLAC3{sup D} at the M3 longwall panel of the Omerler Underground Mine located at Tuncbilek (Turkey) are presented. According to the modeling results, maximum vertical abutment stresses were formed at a distance of 7m in front of the face. An analysis of the conditions of top coal has revealed that a 1.5 m thick layer of coal just above the shield supports is well fractured. However, a 3.5 m thick layer of coal above the fractured part is either not fractured or is fractured in the form of large blocks leading to obstruction of windows of shields during coal drawing. It is concluded that, in order to decrease dilution and increase extraction ratio and efficiency of operation, top coal should be as uniformly fractured as possible. Hence, an efficient and continuous coal flowing behind the face can be maintained. A special pre-fracture blasting strategy just sufficient enough to form cracks in the top coal is suggested by means of comparing with the results of numerical modeling.

THE METHOD OF ASSESSING ROCK BURSTING HAZARD IN MINING

Directory of Open Access Journals (Sweden)

Anna MANOWSKA

2015-04-01

Full Text Available The article discusses a concept of forecasting accident risk during longwall extraction in crump-risk conditions. In Polish mines rock burst hazard can be described as high compared to other mines around the world. It's related to increase of depth of longwall field operation, preparation works, including drilling of mine face pavements which leads to systematic deterioration of geological and mining conditions. Depletion of coal is also the reason why mines operate in high mining tremor risk conditions. Mines more and more often operate in decks, where there is large number of edges and remains of older decks. Rocks bursts still remain one of the most dangerous natural hazards and therefore are fundamental prob-lem and have the greatest impact on safety in mining industry. The proposed method for forecasting accidents and loss-es in people and goods can contribute to improvement of work organization methods and mine safety management system.

Open-air sprays for capturing and controlling airborne float coal dust on longwall faces

Science.gov (United States)

Beck, T.W.; Seaman, C.E.; Shahan, M.R.; Mischler, S.E.

2018-01-01

Float dust deposits in coal mine return airways pose a risk in the event of a methane ignition. Controlling airborne dust prior to deposition in the return would make current rock dusting practices more effective and reduce the risk of coal-dust-fueled explosions. The goal of this U.S. National Institute for Occupational Safety and Health study is to determine the potential of open-air water sprays to reduce concentrations of airborne float coal dust, smaller than 75 µm in diameter, in longwall face airstreams. This study evaluated unconfined water sprays in a featureless tunnel ventilated at a typical longwall face velocity of 3.6 m/s (700 fpm). Experiments were conducted for two nozzle orientations and two water pressures for hollow cone, full cone, flat fan, air atomizing and hydraulic atomizing spray nozzles. Gravimetric samples show that airborne float dust removal efficiencies averaged 19.6 percent for all sprays under all conditions. The results indicate that the preferred spray nozzle should be operated at high fluid pressures to produce smaller droplets and move more air. These findings agree with past respirable dust control research, providing guidance on spray selection and spray array design in ongoing efforts to control airborne float dust over the entire longwall ventilated opening. PMID:29348700

Open-air sprays for capturing and controlling airborne float coal dust on longwall faces.

Science.gov (United States)

Beck, T W; Seaman, C E; Shahan, M R; Mischler, S E

2018-01-01

Float dust deposits in coal mine return airways pose a risk in the event of a methane ignition. Controlling airborne dust prior to deposition in the return would make current rock dusting practices more effective and reduce the risk of coal-dust-fueled explosions. The goal of this U.S. National Institute for Occupational Safety and Health study is to determine the potential of open-air water sprays to reduce concentrations of airborne float coal dust, smaller than 75 µm in diameter, in longwall face airstreams. This study evaluated unconfined water sprays in a featureless tunnel ventilated at a typical longwall face velocity of 3.6 m/s (700 fpm). Experiments were conducted for two nozzle orientations and two water pressures for hollow cone, full cone, flat fan, air atomizing and hydraulic atomizing spray nozzles. Gravimetric samples show that airborne float dust removal efficiencies averaged 19.6 percent for all sprays under all conditions. The results indicate that the preferred spray nozzle should be operated at high fluid pressures to produce smaller droplets and move more air. These findings agree with past respirable dust control research, providing guidance on spray selection and spray array design in ongoing efforts to control airborne float dust over the entire longwall ventilated opening.

Active methods of preventing bumps in situations where the longwall face advances to and crosses a roadway in thick coal beds

Energy Technology Data Exchange (ETDEWEB)

Loboda, C

1978-01-01

The method was analyzed in the Wujek coal mine, where the coal bed is located at 600 m and was 5.3 m to 5.7 m thick. The following situation is described: A longwall face had to pass through a ventilation tunnel. To reduce the inner stress of the coal mass above and below the ventilation tunnel infusion was used. Water was forced into the walls of the tunnel. The tunnel section was 200 m long, 28 holes were drilled, each 40 m deep, diameter of the bore 42 to 45 mm, water pressure 300 at. To prevent bumps the orientation of the longwall face, which had been parallel to the ventilation tunnel, was changed so that it was at the angle of 15 degrees to the ventilation tunnel. Experience showed that the most dangerous situation in the tunnel arises when the distance between a longwall face and a roadway is reduced to 45 m. At that moment pressure on the road support system is the greatest. The danger of bumps at a longwall face is the greatest when it is 25 m away from a roadway.

Improvements in longwall downtime analysis and fault identification

Energy Technology Data Exchange (ETDEWEB)

Daniel Bongers [CRCMining (Australia)

2006-12-15

In this project we have developed a computer program for recording detailed information relating to face equipment downtime in longwall mining operations. This software is intended to replace the current manual recording of delay information, which has been proven to be inaccurate. The software developed is intended to be operated from the maingate computer. Users are provided with a simple user interface requesting that nature of each delay in production, which is time-stamped in alignment with the SCADA system, removing the need for operators to estimate the start time and duration of each delay. Each instance of non-production is recorded to a database, which may be accessed by surface computers, removing the need for transcribing of the deputy's report into the delay database. An additional suggestive element has been developed, based on sophisticated fault detection technology, which reduces the data input required by operators, and provides a basis for the implementation of real-time fault detection. Both the basic recording software and the suggestive element offer improvements in efficiency and accuracy to longwall operations. More accurate data allows improved maintenance planning and improved measures of operational KPIs. The suggestive element offers the potential for rapid fault diagnosis, and potentially delay forecasting, which may be used to reduce lost time associated with machine downtime.

Development stage of computerization and automation of machines and equipment used at longwall faces in Polish mines. Sostoyanie rabot po ehlektronizatsii i avtomatizatsii mashin i oborudovaniya, ustanavlivaemogo v lave i primenyaemogo v Pol'skikh shakhtakh

Energy Technology Data Exchange (ETDEWEB)

Sobchik, Yu; Pan' kuv, A; Sikora, W [Gornopromyshlennoe Obedinenie po Avtomatizatsii EMAG, Katowice (Poland)

1988-01-01

Discusses development of control equipment and control systems for machines and equipment used in underground black coal mining in Poland. The following types of control systems are comparatively evaluated: control systems for powered supports used at longwall faces (remote control, control of groups of powered support units, control of individual support units), control systems for shearer loaders (control of shearer loader position at a working face, control of motor loading, motor heating, pressure in hydraulic systems, control of roller bearings etc.), control systems for coal plows (remote start-up of a coal plow and auxiliary equipment, communications between coal miners at a working face, control of motor loading, control of cutting head position, water spraying, etc.), sensors used in control systems and control equipment. Development trends of control systems for equipment used at longwall faces are discussed.

Developments in the application of underground battery vehicles in the UK coal mining industry

Energy Technology Data Exchange (ETDEWEB)

Fortune, J A.B.; Crawshaw, S A.M. [Long-Airdox International Ltd. (United Kingdom)

1996-10-01

Trackless battery powered haulage vehicles have been in operation in British coal mines principally for longwall face transfer and personnel transportation. Changes within the industry have resulted in the introduction of room and pillar coal mining methods and the introduction of increasingly heavier longwall roof supports. This has resulted in the introduction of: battery powered coal haulage machines, which, without the need for trailing cables, increase productivity within room and pillar mining; and battery powered longwall shield haulers which are capable of carrying the heaviest shield supports currently being utilised within the British coal mining industry. The conventional machines have been adapted from an American design to meet the requirements of European legislation. This has seen the emphasis being placed upon the supplier with the European Machinery Directive being introduced, necessitating the assigning of a `CE` mark to each vehicle. Battery vehicle technology has advanced to meet the demands of the ever changing market and will no doubt be further adapted to meet the requirement of the British coal mining industry. 1 ref., 12 figs., 3 tabs.

A methodology for determining the evolution law of gob permeability and its distributions in longwall coal mines

International Nuclear Information System (INIS)

Zhang, Cun; Tu, Shihao; Zhang, Lei; Bai, Qingsheng; Yuan, Yong; Wang, Fangtian

2016-01-01

In order to understand the permeability evolution law of the gob by mining disturbances and obtain the permeability distribution of the fully compacted gob, comprehensive methods including theoretical analyses of monitoring data and numerical simulation are used to determine the permeability of gobs in the mining process. Based on current research, three zones of the vertical stress and permeability in the gob are introduced in this article, which are the caving rock mass accumulation zone, the gradually compacted zone and the fully compacted zone. A simple algorithm is written by using FISH language to be imported into the reservoir model. FISH language is an internal programming language in FLAC3D. It is possible to calculate the permeability at each zone with this algorithm in the mining process. Besides, we analyze the gas flow rates from seven gob gas ventholes (GGV) located on a longwall face operated in a mine of a Huainan coalfield in Huainan City, China. Combined with Darcy’s law, a calculation model of permeability around GGV in the gob is proposed. Using this model, the evolution law of permeability in the gob is deduced; the phases of permeability evolution are the decline stage and the stable stage. The result of the vertical stress monitoring data and good fitting effect of the permeability to the experimental data show that the permeability decline caused by the compaction of the gob is the principal reason for the decline stage. The stable stage indicates that the gob has been fully compacted, and the average period of full gob compaction is 47.75 d. The permeability in the middle of the compacted gob is much smaller than the permeability on the edge of the gob which presents an O shape trend. Besides, the little difference among the results of the numerical simulation, the permeability calculation model and other commonly used calculation models validate the correctness of the permeability calculation model and numerical simulation results

Relaxation and gas drainage boreholes for high performance longwall operations in low permeability coal seams

Energy Technology Data Exchange (ETDEWEB)

Imgrund, Thomas [DMT GmbH und Co. KG, Essen (Germany); Bauer, Frank [Hazemag und EPR GmbH, Duelmen (Germany). Mining

2013-06-15

With an increasing depth of cover, gas emission control and gas outbursts prevention has become an increasingly important issue in coal mining. Deep multi-seam mining often requires operation in an environment characterised by a high gas content and gas pressure. Control of gas related risks has to be realised during heading and close to the longwall by proper risk assessment and flexible drilling schemes. These cover exploration and relaxation drilling, in-seam drilling for pre-drainage and cross measure drilling for drainage of roof and the floor gas emissions. DMT provides comprehensive solutions based on a scientific background. These solutions are engineered considering their technical feasibility. Hazemag Mining offers a large number of complete machinery including tools systems for the implementation of those solutions. (orig.)

Analysis of Influence of Goaf Sealing from Tailgate On the Methane Concentration at the Outlet from the Longwall

Science.gov (United States)

Tutak, Magdalena; Brodny, Jaroslaw

2017-12-01

One of the most common and most dangerous gas hazards in underground coal mine is methane hazard. Formation of dangerous, explosive concentrations of methane occurs the most often in the region of crossing of longwall with the ventilation gallery. Particularly it applies to longwalls ventilated in „U from bounds” system. Outflow of gases from the goaf to the tailgate takes place through the boundary surfaces of this sidewalk with goaf. Main cause of this process is a phenomenon of air filtration through the goaf with caving. This filtration is a result of migration of the part of ventilation air stream supplied to the longwall. This air is released into the goaf on the entire longwall length; however, its greater amount gets to the goaf with caving space at the crossing of maingate with exploitation longwall. Albeit, the biggest outflow of air mixture and gases from the goaf occurs in top gate in upper corner of the longwall. This is a result of pressure difference in this region. This phenomenon causes that to the space of heading besides the air also other gases present in the goaf, mainly methane, are released. Methane is an explosive gas. Most often boundaries of explosive mixtures of methane, air and inert gases are described by the so-called Coward triangle explosion. Within the limits of the occurrence of the concentration of explosive methane explosion initials may be endogenous fire, blasting or sparks arising from friction of moving lumps of rock. Therefore, in order to decrease its concertation in this region, by limiting its outflow from the goaf with caving different actions are taken. One of such action is sealing of goaf from top gate side. Analysis of impact of sealing of these goaf on the methane concentration at the outlet of longwall is main aim of studies researches. Model of tested region, together with boundary conditions (including parameters of flowing air and the methane content) was developed on the base of real data from one of the

Stochastic modeling of gob gas venthole production performances in active and completed longwall panels of coal mines

Energy Technology Data Exchange (ETDEWEB)

Karacan, C. Oezgen [NIOSH, Office of Mine Safety and Health Research, Pittsburgh, PA (United States); Luxbacher, Kray [Virginia Tech, Dept. of Mining and Minerals Engineering, Blacksburg, VA (United States)

2010-11-01

Gob gas ventholes (GGVs) are an integral part of longwall coal mining operations, enhancing safety by controlling methane in underground workings. As in many disciplines in earth sciences, uncertainties due to the heterogeneity of geologic formations exist. These uncertainties, and the wide range of mining and venthole operation parameters, lead to performance variability in GGVs. Random variations in parameters affecting GGV performance and influencing parameters that cannot be quantified sufficiently due to lack of information limit deterministic GGV models and even introduce error in severe cases. Therefore, evaluation of GGV performance data and the uncertainty in input parameters is valuable for understanding the variability in GGV production and for designing them accordingly. This paper describes a practical approach for implementing stochastic determination of GGV production performances and for generalizing the prediction capability of deterministic models. Deterministic site-specific models were derived by using the GGV module in the recently developed MCP (Methane Control and Prediction) software suite. These models were generated using multi-parameter regression techniques and were then improved by inclusion of extra input parameters that eliminated the site dependency and improved the predictions. Statistical distributions of input parameters in these models were quantified and tested with the Kolmogorov-Smirnov goodness-of-fit technique. Next, Monte Carlo simulations were performed using these distributions and generalized results for GGV performances were generated. The results of this work indicate that this approach is a promising method of representing the variability in GGV performances and to improve the limited and site-specific character of the deterministic models. (author)

Developments in mechanization of operations of comprehensively mechanized longwalls in the USSR and abroad. Sovershenstvovanie sredstv mekhanizatsii kontsevykh operatsii v kompleksno-mekhanizirovannykh lavakh v SSSR i za rubezhom

Energy Technology Data Exchange (ETDEWEB)

Bodrunov, L D

1985-01-01

This paper discusses construction and introduction of equipment for mining at junctions of longwalls and roadways. Design and operation of a Soviet made narrow web shearer loader with chainless advance, enabling coal extraction by side cutting without the provision of stables in seams 2-4.1 m thick and up to 30 degrees inclination are described along with two types (520 mm and 630 mm high) of narrow web shearer loaders for extracting 0.7-0.95 m and 0.8-1.2 m thick seams with inclinations up to 35 degrees. Three types of machines constructed to operate in thin seams are presented. They are designed to extract coal from seams: 0.6-1.3 m thick with shear strength of 2.5 kN/cm, 0.65-1.2 m thick with shear strength up to 3.0 kN/cm and seams 0.8-1.8 m thick also with 3.0 kN/sm shear strength. Stableless extraction is also possible due to developments which have taken place in face scraper conveyors with shortened driving heads. Some of the new conveyors can be used in normal complexes to extract flat and inclined seams 1-2.5 m thick, whilst others are used to extract flat and inclined thin seams (0.7-1.2 m). The use of two shearer loaders has resulted in reduction in stable size or stableless extraction. Mechanization of supports at junctions of longwalls and mine roadways by means of metal supporting beams in conjunction with hydraulic or friction props is described. Mechanization of similar operations in foreign mines is also described, e.g. stableless extraction in the UK, where up to 80% of coal is extracted by the longwall system and 20% by the pillar system using the two shearer loader method. Machines produced by Anderson Strathclyde, Mining Supplies, and British Jeffrey Diamond and props manufactured by Dowty and Gullick Dobson are described. FRG coal extraction is carried out chiefly (95%) from inclined seams more than 4 m thick, using a pillar mining system (25%), longwall system (58%) and combined (17%).

Determination of Particular Endogenous Fires Hazard Zones in Goaf with Caving of Longwall

Science.gov (United States)

Tutak, Magdalena; Brodny, Jaroslaw

2017-12-01

Hazard of endogenous fires is one of the basic and common presented occupational safety hazards in coal mine in Poland and in the world. This hazard means possibility of coal self-ignition as the result of its self-heating process in mining heading or its surrounding. In underground coal-mining during ventilating of operating longwalls takes place migration of parts of airflow to goaf with caving. In a case when in these goaf a coal susceptible to selfignition occurs, then the airflow through these goaf may influence on formation of favourable conditions for coal oxidation and subsequently to its self-heating and self-ignition. Endogenous fire formed in such conditions can pose a serious hazard for the crew and for continuity of operation of mining plant. From the practical point of view, a very significant meaning has determination of the zone in the goaf with caving, in which necessary conditions for occurrence of endogenous fire are fulfilled. In the real conditions determination of such a zone is practically impossible. Therefore, authors of paper developed a methodology of determination of this zone basing on the results of modelling tests. This methodology includes a development of model of tested area, determination of boundary conditions and carrying out the simulation calculations. Based on the obtained results particular hazardous zone of endogenous fire is determined. A base for development of model of investigated region and selection of boundary conditions are the results of real tests. In the paper fundamental assumption of developed methodology, particularly in a range of assumed hazard criterion and sealing coefficient of goaf with caving were discussed. Also a mathematical model of gas flow through the porous media was characterized. Example of determination of a zone particularly endangered by endogenous fire for real system of mining heading in one of the hard coal mine was presented. Longwall ventilated in the „Y” system was subjected to the

Methods for protecting mine roadways used by two faces

Energy Technology Data Exchange (ETDEWEB)

Katkov, G A; Dimanshtein, A S

1983-09-01

Use of a mine roadway by two longwall faces reduces mine drivage by half and positively influences ventilation and mine haulage. Economic effects of repeated use of mine roadways depend on strata control cost and repair of support systems damaged or deformed by rock strata stress. Use of strips of pneumatic stowing along mine roadways is uneconomical due to low support strength and significant subsidence of the waste rock strip under rock strata stress. Use of timber cribbings as well as blocks of reinforced concrete for strata control is uneconomical due to their high damage rate and low support capacity. Investigations carried out by the IGD Im. A.A. Skochinski Institute and other research institutes show that use of hardening stowing is superior to other methods for strata control in mine roadways used by two longwall faces. Hardening stowing (on a cement basis) is prepared by the SB-67 or the PBM-2Eh machines and by other systems used for guniting in coal mines. The optimum dimensions of a strip of hardening stowing depend on coal seam thickness and mechanical properties of the surrounding rock strata. Use of hardening stowing successfully controls roof subsidence in mine roadways and reduces support deformation. Examples of hardening stowing use in some Donbass coal mines are discussed.

Sequential Gaussian co-simulation of rate decline parameters of longwall gob gas ventholes

Science.gov (United States)

Karacan, C. Özgen; Olea, Ricardo A.

2013-01-01

Gob gas ventholes (GGVs) are used to control methane inflows into a longwall mining operation by capturing the gas within the overlying fractured strata before it enters the work environment. Using geostatistical co-simulation techniques, this paper maps the parameters of their rate decline behaviors across the study area, a longwall mine in the Northern Appalachian basin. Geostatistical gas-in-place (GIP) simulations were performed, using data from 64 exploration boreholes, and GIP data were mapped within the fractured zone of the study area. In addition, methane flowrates monitored from 10 GGVs were analyzed using decline curve analyses (DCA) techniques to determine parameters of decline rates. Surface elevation showed the most influence on methane production from GGVs and thus was used to investigate its relation with DCA parameters using correlation techniques on normal-scored data. Geostatistical analysis was pursued using sequential Gaussian co-simulation with surface elevation as the secondary variable and with DCA parameters as the primary variables. The primary DCA variables were effective percentage decline rate, rate at production start, rate at the beginning of forecast period, and production end duration. Co-simulation results were presented to visualize decline parameters at an area-wide scale. Wells located at lower elevations, i.e., at the bottom of valleys, tend to perform better in terms of their rate declines compared to those at higher elevations. These results were used to calculate drainage radii of GGVs using GIP realizations. The calculated drainage radii are close to ones predicted by pressure transient tests.

Preliminary report on LLNL mine seismicity deployment at the Twentymile Coal Mine

International Nuclear Information System (INIS)

Walter, W.R.; Hunter, S.L.; Glenn, L.A.

1996-01-01

This report summarizes the preliminary results of a just completed experiment at the Twentymile Coal Mine, operated by the Cyprus Amax Coal Company near Oak Creek, CO. The purpose of the experiment was to obtain local and regional seismic data from roof caves associated with long-wall mining activities and to use this data to help determine the effectiveness with which these events can be discriminated from underground nuclear explosions under a future Comprehensive Test Ban Treaty

Tomographic imaging of rock conditions ahead of mining using the shearer as a seismic source - A feasibility study

Energy Technology Data Exchange (ETDEWEB)

Luo, X.; King, A.; Van de Werken, M. [CSIRO, Brisbane, Qld. (Australia)

2009-11-15

Roof falls due to poor rock conditions in a coal longwall panel may threaten miner's life and cause significant interruption to mine production. There has been a requirement for technologies that are capable of imaging the rock conditions in longwall coal mining, ahead of the working face and without any interruption to production. A feasibility study was carried out to investigate the characteristics of seismic signals generated by the continuous coal cutter (shearer) and recorded by geophone arrays deployed ahead of the working face, for the purpose of seismic tomographic imaging of roof strata condition before mining. Two experiments were conducted at a coal mine using two arrays of geophones. The experiments have demonstrated that the longwall shearer generates strong and low-frequency (similar to 40 Hz) seismic energy that can be adequately detected by geophones deployed in shallow boreholes along the roadways as far as 300 m from the face. Using noise filtering and signal cross correlation techniques, the seismic arrival times associated with the shearer cutting can be reliably determined. It has proved the concept that velocity variations ahead of the face can be mapped out using tomographic techniques while mining is in progress.

Strata control in deep coal mines. Control de estratos en tajos subteraneos de la mineria del carbon

Energy Technology Data Exchange (ETDEWEB)

Ramirez Oyanguren, P.; De la Cuadra, L.

1985-01-01

The six chapters cover the following subjects: mining methods used in Spanish coal mines; rock movement and pressure around a longwall face; roof bed study; underground support systems; gas dynamic phenomena; and instrumentation for underground mine monitoring.

Internet technologies in the mining industry. Towards unattended mining systems

Energy Technology Data Exchange (ETDEWEB)

Krzykawski, Michal [FAMUR Group, Katowice (Poland)

2009-08-27

Global suppliers of longwall systems focus mainly on maximising the efficiency of the equipment they manufacture. Given the fact that, since 2004, coal demand on world markets has been constantly on the increase, even during an economic downturn, this endeavour seems fully justified. However, it should be remembered that maximum efficiency must be accompanied by maximum safety of all underground operations. This statement is based on the belief that the mining industry, which exploits increasingly deep and dangerous coal beds, faces the necessity to implement comprehensive IT systems for managing all mining processes and, in the near future, to use unmanned mining systems, fully controllable from the mine surface. The computerisation of mines is an indispensable element of the development of the world mining industry, a belief which has been put into practice with e-mine, developed by the FAMUR Group. (orig.)

Experimental use of road header (AM-50) as face cutting machine for extraction of coal in longwall panel

Energy Technology Data Exchange (ETDEWEB)

Passi, K.K.; Kumar, C.R.; Prasad, P. [DGMS, Dhanbad (India)

2001-07-01

The scope of this paper has been limited to the use of available machines and techniques for attaining higher and more efficient production in underground coal mines. Under certain conditions of strata and higher degree of gassiness, the longwall method with hydraulic sand stowing is the only appropriate method of work for extraction of thick seam. In Moonidih Jitpur Colliery of M/S IISCO, No. 14 seam, Degree III gassy seam, 9.07 m thick, is extracted in multilift system with hydraulic sand stowing. In general, the bottom lift is extracted by Single Ended Ranging Arm Shearer and the middle and top lift are extracted by conventional method. However, in one of the panels spare road header machine was used as face cutting machine in bottom lift, on an experimental basis. This paper presents a successful case study of extraction of bottom lift coal by the longwall method with hydraulic sand stowing using road header (AM 50) as the face cutting machines. 9 figs.

Long-hole destress blasting for rockburst control during deep underground coal mining

Czech Academy of Sciences Publication Activity Database

Koníček, Petr; Souček, Kamil; Staš, Lubomír; Singh, R.

-, č. 61 (2013), s. 141-153 ISSN 1365-1609 R&D Projects: GA MŠk ED2.1.00/03.0082 Institutional support: RVO:68145535 Keywords : Ostrava - Karvina Coal basin * longwall mining * rockbursts * destress blasting Subject RIV: DH - Mining, incl. Coal Mining Impact factor: 1.424, year: 2013 http://www.sciencedirect.com/science/article/pii/S1365160913000348

Coal Mine Accidents in Bangladesh: Its Causes and Remedial Measures

Directory of Open Access Journals (Sweden)

MD. MINHAJ UDDIN MONIR

2012-12-01

Full Text Available Barapukuria coal mine (BCM is located at Dinajpur district, NW Bangladesh. Total area is about 6.68 km2 and coal was encountered at a depth ranging between 118 and 509 m. Six major coal seams (seam I to seam VI were identified at BCM, of which, thickest one is the seam-VI (~36 m. The estimated coal reserves is about 390 million tons and of this, nearly 64 million tons of coal is extractable. The annual production of coal is about 1 million ton. In this study several parameters were used to explore minimization of accidents and improvement of coal production in BCM. Considering the geological, hydrological and other technical parameters, longwall mining method is applied for extraction of coal. Longwall retreating mining method is also applied for extraction of coal from single face with the operational area protected by self-advancing hydraulic powered roof support (HPRS system. These supports are moved forward causing the roof behind them to form an extensive abandoned area named goaf, which may lead to collapse with air blast. Coal in BCM is extracted from seam VI, using a multislice Longwall top coal caving method. Average ventilated air composition is ~20.94% oxygen, ~79.00% nitrogen, ~0.04% carbon monoxide, and minor water steam with huge dust. Production of coal was completed from 12 Longwall faces of 1st slice from seam VI. During production period several accidents and troubles within BCM have occurred. Poisonous gases such as carbon monoxide were detected during/after development of 1110 Longwall face, which increases up to 6000 ppm, therefore, sealed-off the face with mining equipments. During the development of belt gate roadway of 1101 Longwall face, maximum temperature and humidity increases up to 37 oC and 100%, respectively. Miners of BCM experienced some difficulties to work in that adverse environment. Air return roadway temperature was always 40 to 41oC in 1101 Longwall face during production period, faces temperature 46o

Forecasts of methane concentration at the outlet of the longwall with caving area - case study

Science.gov (United States)

Badura, Henryk; Bańka, Piotr; Musioł, Dariusz; Wesołowski, Marek

2017-11-01

This paper presents the characteristics of methane hazard and prevention undertaken in the N-6 longwall of seam 330/2 in “Krupiński" coal mine. On the basis of methane concentration measurements conducted with the use of telemetric system, time series of the average and maximum methane concentration at the outlet of the longwall area were generated. It was ascertained that they exhibit a strong autocorrelation. Based on a series of the average methane concentration, a time series of ventilation methane content was created and a total methane content was calculated with the use of methane flow rate measurements in the demethanization system. It was ascertained that dependence between methane concentration and output on the examined day and on the previous day is weak and also that the dependence between methane concentration and air flow rate is very weak. Dependencies between ventilation methane content, total methane content and demethanization efficiency were also investigated. Based on forecasting models [1] developed earlier by H. Badura, forecasts have been made to predict the average and maximum methane concentrations. The measured values f methane concentration show a high level of accordance with forecasted ones.

Assessment of surface and subsurface ground disturbance due to underground mining

International Nuclear Information System (INIS)

Khair, A.W.

1994-01-01

This paper presents highlights of the research carried out at West Virginia University in order to assess surface and subsurface ground disturbance due to longwall mining. Extensive instrumentation and measurements have been made over three longwall mines in northern West Virginia during a three-year period. Various monitoring techniques including full profile borehole extensometer, full profile borehole inclinometers, time domain reflectometry, sonic reflection technique, a unique mechanical grouting method, photographic and visual observations, standard surveying, and water-level measurements were utilized. The paper's emphasis is first on surface ground movement and its impact on integrity of surface ground and structures and second on type and magnitude of subsurface ground movements associated with mine geometry and geology. A subsidence prediction model based on implementation of both mechanisms of ground movement around the excavation and the geologic and geotechnical properties of the rock/coal surrounding the excavation has been developed. 8 refs., 14 figs., 1 tab

Remote mining for in-situ waste containment. Final report

Energy Technology Data Exchange (ETDEWEB)

Martinelli, D.; Banta, L.; Peng, S. [and others

1995-10-01

This document presents the findings of a study conducted at West Virginia University to determine the feasibility of using a combination of longwall mining and standard landfill lining technologies to mitigate contamination of groundwater supplies by leachates from hazardous waste sites.

Remote mining for in-situ waste containment. Final report

International Nuclear Information System (INIS)

Martinelli, D.; Banta, L.; Peng, S.

1995-10-01

This document presents the findings of a study conducted at West Virginia University to determine the feasibility of using a combination of longwall mining and standard landfill lining technologies to mitigate contamination of groundwater supplies by leachates from hazardous waste sites

Development of ZL400 Mine Cooling Unit Using Semi-Hermetic Screw Compressor and Its Application on Local Air Conditioning in Underground Long-Wall Face

Science.gov (United States)

Chu, Zhaoxiang; Ji, Jianhu; Zhang, Xijun; Yan, Hongyuan; Dong, Haomin; Liu, Junjie

2016-12-01

Aiming at heat injuries occurring in the process of deep coal mining in China, a ZL400 mine-cooling unit employing semi-hermetic screw compressor with a cooling capacity of 400 kW is developed. This paper introduced its operating principle, structural characteristics and technical indexes. By using the self-built testing platform, some parameters for indication of its operation conditions were tested on the ground. The results show that the aforementioned cooling unit is stable in operation: cooling capacity of the unit was 420 kW underground-test conditions, while its COP (coefficient of performance) reached 3.4. To address the issue of heat injuries existing in No. 16305 U-shaped long-wall ventilation face of Jining No. 3 coal mine, a local air conditioning system was developed with ZL400 cooling unit as the system's core. The paper presented an analysis of characteristics of the air current flowing in the air-mixing and cooling mode of ZL400 cooling unit used in air intake way. Through i-d patterns we described the process of the airflow treatment, such as cooling, mixing and heating, etc. The cooling system decreased dry bulb temperature on working face by 3°C on average and 3.8°C at most, while lowered the web bulb temperature by 3.6°C on average and 4.8°C at most. At the same time, it reduced relative humidity by 5% on average and 8.6% at most. The field application of the ZL400 cooling unit had gain certain effects in air conditioning and provided support for the solution of mine heat injuries in China in terms of technology and equipment.

Tube bundle system: for monitoring of coal mine atmosphere.

Science.gov (United States)

Zipf, R Karl; Marchewka, W; Mohamed, K; Addis, J; Karnack, F

2013-05-01

A tube bundle system (TBS) is a mechanical system for continuously drawing gas samples through tubes from multiple monitoring points located in an underground coal mine. The gas samples are drawn via vacuum pump to the surface and are typically analyzed for oxygen, methane, carbon dioxide and carbon monoxide. Results of the gas analyses are displayed and recorded for further analysis. Trends in the composition of the mine atmosphere, such as increasing methane or carbon monoxide concentration, can be detected early, permitting rapid intervention that prevents problems, such as a potentially explosive atmosphere behind seals, fire or spontaneous combustion. TBS is a well-developed technology and has been used in coal mines around the world for more than 50 years. Most longwall coal mines in Australia deploy a TBS, usually with 30 to 40 monitoring points as part of their atmospheric monitoring. The primary uses of a TBS are detecting spontaneous combustion and maintaining sealed areas inert. The TBS might also provide mine atmosphere gas composition data after a catastrophe occurs in an underground mine, if the sampling tubes are not damaged. TBSs are not an alternative to statutory gas and ventilation airflow monitoring by electronic sensors or people; rather, they are an option to consider in an overall mine atmosphere monitoring strategy. This paper describes the hardware, software and operation of a TBS and presents one example of typical data from a longwall coal mine.

The design of a mechanical referencing system for the rear drum of the Longwall Shearer Coal Miner

Science.gov (United States)

Jones, E. W.; Yang, T. C. H.

1981-01-01

The design of two systems which reference the position of a longwall shearer coal miner to the mine roof of the present cut and of the last cut are presented. This system is part of an automation system that will guide the rear cutting drum in such a manner that the total depth of cut remains constant even though the front drum may be following an undulating roof profile. The rear drum referencing mechanism continually monitors the distance from the mine roof to the floor for the present cut. This system provides a signal to control a constant depth of cut. The last cut follower mechanism continually monitors the distance from the mine roof of the prior cut to the cutting drum. This latter system provides a signal to minimize the step height in the roof between cuts. The dynamic response of this hydraulic-pneumatic and mechanical system is analyzed to determine accumulator size and precharge pressure.

The influence of subsidence attributable to coal mining on the environment, development and restoration: some examples from western Europe and South Africa

Energy Technology Data Exchange (ETDEWEB)

Bell, F.G.; Genske, D.D. [University of Natal, Durban (South Africa). Dept. of Geology & Applied Geology

2001-02-01

One of the consequences of coal mining is subsidence, and it is associated with past and present mine workings. Indeed, old abandoned coal mines worked by the room-and-pillar method, which occur at shallow depth, often present a potential hazard as pillars collapse or voids migrate to the surface. Frequently, the situation is compounded by the fact that such workings are unrecorded. Subsidence prediction in such cases is impossible. In longwall mining, the total extraction of panels takes place, the working face being supported, while support is removed from behind the working face allowing the roof to collapse. Subsidence consequent on longwall mining can be regarded as more or less contemporaneous with mining and is normally predictable. This means that it is possible to develop an area after subsidence due to longwall mining has occurred or to incorporate features into the design of buildings and structures that will accommodate ground movements generated by subsidence. The nature of subsidence can be affected by discontinuities in the surface strata or the presence of superficial deposits. Of course, subsidence can adversely affect existing buildings and structures which do not incorporate special design features. In severe cases of subsidence damage, buildings may have to be demolished. Important buildings may be restored. Another problem associated with subsidence is flooding due to notable lowering of the ground surface. Examples of such problems and solutions are highlighted by the examples given.

High pressure water jet mining machine

Science.gov (United States)

Barker, Clark R.

1981-05-05

A high pressure water jet mining machine for the longwall mining of coal is described. The machine is generally in the shape of a plowshare and is advanced in the direction in which the coal is cut. The machine has mounted thereon a plurality of nozzle modules each containing a high pressure water jet nozzle disposed to oscillate in a particular plane. The nozzle modules are oriented to cut in vertical and horizontal planes on the leading edge of the machine and the coal so cut is cleaved off by the wedge-shaped body.

Coal mining technologies possible for use in the Polish hard coal mining sector ensuring its sustainable development; Technologie eksploatacji wegla mozliwe do zastosowania w polskim gornictwie wegla kamiennego zapewniajace jego zrownowazony rozwoj

Energy Technology Data Exchange (ETDEWEB)

Dubinski, J. [Central Mining Institute, Katowice (Poland)

2004-07-01

The paper presents a prediction of the developments in hard coal mining technologies both in Poland and in the world. The longwall and the room-and-pillar systems will be realised. In Poland longwall equipment must be made more reliable and be better monitored, and more use made of roof bolting and means of controlling methane and rockbursts. Methods of underground gasification of coal seams need further development to realise the potential of this resource at reasonable production cost and with minimal environmental impact. 38 refs., 6 figs., 4 tabs.

Protecting mine roadways used for the second time in the Komsomolets Donbassa mine

Energy Technology Data Exchange (ETDEWEB)

Zaslavskii, I Yu; Boev, N A; Churakov, V N

1983-12-01

This paper evaluates methods for strata control in gate roads used in the Komsomolets Donbassa mine with 2 coal seams from 1 to 1.1 m thick at depths of 418 m and 624 m, with dip angles from 5 to 10 degrees. Long pillars are mined by a system of longwall faces with caving. The following methods for strata control in gate roads are comparatively evaluated: use of blocks made of reinforced concrete, use of timber cribbings, combined use of concrete blocks or cribbings and strips of pneumatic stowing from 8 to 12 m wide, use of thin coal support pillars (from 2 to 3 m). Investigation results are shown in 4 diagrams. Analyses show that use of blocks made of reinforced concrete or concrete blocks combined with strips of pneumatic stowing does not prevent excessive roof subsidence and support deformation. Use of coal support pillars from 2 to 3 m wide is not recommended due to considerable cost and coal losses. Use of timber cribbings combined with strips of pneumatic stowing is most expedient. Recommendations on using timber cribbings and pneumatic stowing for strata control in gate roads used by the next longwall face are made. (In Russian)

Fiscal 1997 technological survey report. Engineer exchange project - coal mine technological field (Advanced coal producing country survey - U.S.A. survey); 1997 nendo gijutsusha koryu jigyo (tanko gijutsu bun'ya) senshin santankoku chosa. Beikoku chosa

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

While the introduction and adaptation of the Longwall excavation technology were carried forward for coal producing countries in the Pacific region, U.S.A. information was collected by making tours of coal mines in the West and Washington/Colorado/Utah States, with the intention of ascertaining technological trend so as to carry out efficient technological transfer, and for the purpose of replenishing the contents and contributing to the smooth implementation of the engineer exchange project in 'coal mine technological field'. The coal reserves are 400 billion tons, with 840 million tons produced and with 80 million tons exported; not less than 56% of the U.S. domestic electricity rests on coal. Production by open-pit mining is the majority while the output by underground mining is 38%; the Longwall method has increased as a digging method, taking 18% of all digging output. The productivity is 4.24 ton/person per day and ranks as the world highest. The coal mining technological trend in the U.S. can be summarized as follows. The coal mining output in the West is increasing, with the number of mines decreasing, so that the output per mine is increasing. With the output ratio by open-pit mining increasing, the digging method in the mine is being changed to the Longwall. (NEDO)

Analysis and Optimization of Entry Stability in Underground Longwall Mining

Directory of Open Access Journals (Sweden)

Yubing Gao

2017-11-01

Full Text Available For sustainable utilization of limited coal resources, it is important to increase the coal recovery rate and reduce mine accidents, especially those occurring in the entry (gateroad. Entry stabilities are vital for ventilation, transportation and other essential services in underground coal mining. In the present study, a finite difference model was built to investigate stress evolutions around the entry, and true triaxial tests were carried out at the laboratory to explore entry wall stabilities under different mining conditions. The modeling and experimental results indicated that a wide coal pillar was favorable for entry stabilities, but oversize pillars caused a serious waste of coal resources. As the width of the entry wall decreased, the integrated vertical stress, induced by two adjacent mining panels, coupled with each other and experienced an increase on the entry wall, which inevitably weakened the stability of the entry. Therefore, mining with coal pillars always involves a tradeoff between economy and safety. To address this problem, an innovative non-pillar mining technique by optimizing the entry surrounding structures was proposed. Numerical simulation showed that the deformation of the entry roof decreased by approximately 66% after adopting the new approach, compared with that using the conventional mining method. Field monitoring indicated that the stress condition of the entry was significantly improved and the average roof pressure decreased by appropriately 60.33% after adopting the new technique. This work provides an economical and effective approach to achieve sustainable exploitation of underground coal resources.

Effects of torpedo blasting on rockburst prevention during deep coal seam mining in the Upper Silesian Coal Basin

Directory of Open Access Journals (Sweden)

Ł. Wojtecki

2017-08-01

Full Text Available In the Upper Silesian Coal Basin (USCB, coal seams are exploited under progressively more difficult geological and mining conditions (greater depth, higher horizontal stress, more frequent occurrence of competent rock layers, etc.. Mining depth, dislocations and mining remnants in coal seams are the most important factors responsible for the occurrence of rockburst hazards. Longwall mining next to the mining edges of neighbouring coal seams is particularly disadvantageous. The levels of rockburst hazards are minimised via the use of rockburst prevention methods. One active prevention method is torpedo blasting in roof rocks. Torpedo blastings are performed in order to decrease local stress concentrations in rock masses and to fracture the roof rocks to prevent or minimise the impact of high-energy tremors on excavations. The estimation of the effectiveness of torpedo blasting is particularly important when mining is under difficult geological and mining conditions. Torpedo blasting is the main form of active rockburst prevention in the assigned colliery in the Polish part of the USCB. The effectiveness of blasting can be estimated using the seismic effect method, in which the seismic monitoring data and the mass of explosives are taken into consideration. The seismic effect method was developed in the Czech Republic and is always being used in collieries in the Czech part of the coal basin. Now, this method has been widely adopted for our selected colliery in the Polish part of the coal basin. The effectiveness of torpedo blastings in the faces and galleries of the assigned longwall in coal seam 506 has been estimated. The results show that the effectiveness of torpedo blastings for this longwall was significant in light of the seismic effect method, which corresponds to the in situ observations. The seismic effect method is regularly applied to estimating the blasting effectiveness in the selected colliery.

3-D numerical modelling of stresses around a longwall panel with top coal caving

Energy Technology Data Exchange (ETDEWEB)

Yasitli, N.E.; Unver, B. [University of Hacettepe, Ankara (Turkey). Dept. of Mining Engineering

2005-06-01

There is a considerable amount of lignite reserve in the form of thick seams in Turkey. It is rather complicated to predict the characteristics of strata response to mining operation in thick seams. However, a comprehensive evaluation of ground behaviour is a prerequisite for maintaining an efficient production, especially when top coal winning by means of caving behind the face is applied. A comprehensive modelling of deformations and induced stresses is vital for the selection of optimum production strategy. In this study, numerical modelling and analysis of a longwall panel at Omerler underground coalmine have been carried out by using the software called FLAC(3D) developed based on the finite difference technique. Firstly, a 3-D numerical model of the M3 panel has been prepared. Secondly, induced stresses formed around the longwall face have been determined as a function of face advance where the face was located at the bottom of thick coal-seam. Results obtained from modelling studies have revealed that the front abutment vertical stress was maximum at 7 metres in front of the face and magnitude of front abutment stress was found to increase up to a distance of 200 metres away from the face start line. As the face was further advanced after 200 m from the face start line, there was not any significant change in the characteristics of front abutment stresses. Results of numerical analysis of the panel were in good agreement with in situ observations.

Computer-based expert system aids underground mine planning

Energy Technology Data Exchange (ETDEWEB)

Britton, S.G.

1987-04-01

Artificial intelligence (AI) systems have been rapidly expanded over the last few years to aid in the decision making processes in a whole range of industries, including the use of machines for operating in high risk/dangerous areas such as at the working faces in longwall mining. Using Prolog software a program for mine management is being developed called CHOOZ. This system can help managers identify staffing problems and change manpower shifts to cope with unexpected labor problems such as absenteeism and sickness. All the programs have been developed for the IBM PC microcomputer.

Grade Distribution Modeling within the Bauxite Seams of the Wachangping Mine, China, Using a Multi-Step Interpolation Algorithm

Directory of Open Access Journals (Sweden)

Shaofeng Wang

2017-05-01

Full Text Available Mineral reserve estimation and mining design depend on a precise modeling of the mineralized deposit. A multi-step interpolation algorithm, including 1D biharmonic spline estimator for interpolating floor altitudes, 2D nearest neighbor, linear, natural neighbor, cubic, biharmonic spline, inverse distance weighted, simple kriging, and ordinary kriging interpolations for grade distribution on the two vertical sections at roadways, and 3D linear interpolation for grade distribution between sections, was proposed to build a 3D grade distribution model of the mineralized seam in a longwall mining panel with a U-shaped layout having two roadways at both sides. Compared to field data from exploratory boreholes, this multi-step interpolation using a natural neighbor method shows an optimal stability and a minimal difference between interpolation and field data. Using this method, the 97,576 m3 of bauxite, in which the mass fraction of Al2O3 (Wa and the mass ratio of Al2O3 to SiO2 (Wa/s are 61.68% and 27.72, respectively, was delimited from the 189,260 m3 mineralized deposit in the 1102 longwall mining panel in the Wachangping mine, Southwest China. The mean absolute errors, the root mean squared errors and the relative standard deviations of errors between interpolated data and exploratory grade data at six boreholes are 2.544, 2.674, and 32.37% of Wa; and 1.761, 1.974, and 67.37% of Wa/s, respectively. The proposed method can be used for characterizing the grade distribution in a mineralized seam between two roadways at both sides of a longwall mining panel.

Effect of lithological variations of mine roof on chock shield support using numerical modeling technique

Energy Technology Data Exchange (ETDEWEB)

NONE

2006-09-15

Interaction between chock shield supports, the most popular powered supports in Indian longwall mines, and surrounding coal measure strata is analyzed using finite element models. Thickness and material properties of the main roof, the immediate roof and the coal seam are varied to simulate various geological conditions of Indian coal measure strata. Contact/gap elements are inserted in between the main roof and overburden layer to allow strata separation. Nonlinear material properties are applied with plastic corrections based on Drucker-Prager yield criterion. This paper illustrates effects of lithological variations on shield load, abutment stress, yield zone and longwall face convergence.

Geostatistical modeling of the gas emission zone and its in-place gas content for Pittsburgh-seam mines using sequential Gaussian simulation

Science.gov (United States)

Karacan, C.O.; Olea, R.A.; Goodman, G.

2012-01-01

Determination of the size of the gas emission zone, the locations of gas sources within, and especially the amount of gas retained in those zones is one of the most important steps for designing a successful methane control strategy and an efficient ventilation system in longwall coal mining. The formation of the gas emission zone and the potential amount of gas-in-place (GIP) that might be available for migration into a mine are factors of local geology and rock properties that usually show spatial variability in continuity and may also show geometric anisotropy. Geostatistical methods are used here for modeling and prediction of gas amounts and for assessing their associated uncertainty in gas emission zones of longwall mines for methane control.This study used core data obtained from 276 vertical exploration boreholes drilled from the surface to the bottom of the Pittsburgh coal seam in a mining district in the Northern Appalachian basin. After identifying important coal and non-coal layers for the gas emission zone, univariate statistical and semivariogram analyses were conducted for data from different formations to define the distribution and continuity of various attributes. Sequential simulations performed stochastic assessment of these attributes, such as gas content, strata thickness, and strata displacement. These analyses were followed by calculations of gas-in-place and their uncertainties in the Pittsburgh seam caved zone and fractured zone of longwall mines in this mining district. Grid blanking was used to isolate the volume over the actual panels from the entire modeled district and to calculate gas amounts that were directly related to the emissions in longwall mines.Results indicated that gas-in-place in the Pittsburgh seam, in the caved zone and in the fractured zone, as well as displacements in major rock units, showed spatial correlations that could be modeled and estimated using geostatistical methods. This study showed that GIP volumes may

Principles of integrated modeling of coal seam mining

Energy Technology Data Exchange (ETDEWEB)

Magda, R

1983-01-01

Mathematical modeling of underground coal mining is discussed. Construction of a mathematical model of an underground mine is analyzed. The model is based on integrating the elementary units (modules). A so-called elementary mining field is defined with the example of a longwall face. A model of an elementary coal seam zone is constructed by integrating the elementary mining fields (in time and space) and supplementing them with a suitable model of mine roadway structure. By integrating the elementary coal seam zones a model of mining level is constructed. Such a mathematical model is used for optimizing the selected mining parameters e.g. structure of mine roadways, size of a coal mine, and organizational scheme of underground mining in a mine or in a mine section using the standardized optimization criterion e.g. investment. Use of the integration model of underground mining for optimizing coal mine construction is evaluated. The following elements of investment and operating cost are considered: shaft excavation, shaft equipment, investment in mining sections, ventilation, mine draining etc. 1 reference.

Mechanism of rigid overlaying of carboniferous strata failure in face mining in the case of multiseams deposit

Czech Academy of Sciences Publication Activity Database

Jiránková, E.; Staš, Lubomír; Kajzar, Vlastimil; Doležalová, Hana

2013-01-01

Roč. 10, č. 2 (2013), s. 189-195 ISSN 1214-9705 R&D Projects: GA MŠk ED2.1.00/03.0082; GA MV VG20102014034 Institutional support: RVO:68145535 Keywords : subsidence trough * rock mass * overlaying strata * longwall mining * tensor stress measurement Subject RIV: DH - Mining, incl. Coal Mining Impact factor: 0.667, year: 2013 http://www.irsm.cas.cz/materialy/acta_content/2013_02/acta_170_08_Jirankova_189-195.pdf

Finite element modeling of surface subsidence induced by underground coal mining

International Nuclear Information System (INIS)

Su, D.W.H.

1992-01-01

The ability to predict the effects of longwall mining on topography and surface structures is important for any coal company in making permit applications and anticipating potential mining problems. The sophisticated finite element model described and evaluated in this paper is based upon five years of underground and surface observations and evolutionary development of modeling techniques and attributes. The model provides a very powerful tool to address subsidence and other ground control questions. The model can be used to calculate postmining stress and strain conditions at any horizon between the mine and the ground surface. This holds the promise of assisting in the prediction of mining-related hydrological effects

Mechanism and Prevention of a Chock Support Failure in the Longwall Top-Coal Caving Faces: A Case Study in Datong Coalfield, China

Directory of Open Access Journals (Sweden)

Zhu Li

2018-01-01

Full Text Available Longwall chock support failures seriously restrain the safety and high-efficiency of mining of extra thick coal seams, as well as causing a great waste of coal resources. During longwall top-coal caving (LTCC, the influential effect of the properties and the movement regulation of top-coal on strata behavior cannot be ignored, since the top-coal is the medium through which the load of the overlying strata is transferred to the chock supports. Taking Datong coalfield as an example, the mechanism of a chock support failure in the LTCC face was investigated. Research findings indicated that the hard top-coal and insufficient chock support capacity were primary reasons for chock support failure accidents. On account of the field-measured results, a new method to determine support capacity was proposed, which fully took the impact of the top-coal strength into consideration. The calculation revealed that the required support capacity had exceeded the existing production maximum, at about 22,000 KN. Since it was unrealistic to simply increase chock support capacity, other approaches, according to the theoretical analysis, were proposed, such as lowering the integrity and strength of the top-coal, and upgrading its crushing effect to weaken the support load effectively during the weighting period, which reduces the likelihood of chock support accidents occurring. Based on this, hydraulic fracturing for hard top-coal and optimization of the caving process (chock supports raised up and down repeatedly by manual operation before moving forward were presented. The proposed solutions were successfully applied in LTCC-west8101 for subsequent mining and achieved substantial benefits. The above research provides valuable references and ideas for the control of strata behavior to ensure safe and highly efficient mining in extremely thick and hard coal seams with the LTCC method.

Ground engineering principles and practices for underground coal mining

CERN Document Server

Galvin, J M

2016-01-01

This book teaches readers ground engineering principles and related mining and risk management practices associated with underground coal mining. It establishes the basic elements of risk management and the fundamental principles of ground behaviour and then applies these to the essential building blocks of any underground coal mining system, comprising excavations, pillars, and interactions between workings. Readers will also learn about types of ground support and reinforcement systems and their operating mechanisms. These elements provide the platform whereby the principles can be applied to mining practice and risk management, directed primarily to bord and pillar mining, pillar extraction, longwall mining, sub-surface and surface subsidence, and operational hazards. The text concludes by presenting the framework of risk-based ground control management systems for achieving safe workplaces and efficient mining operations. In addition, a comprehensive reference list provides additional sources of informati...

Determination of intensity functions for predicting subsidence from coal mining, potash mining, and groundwater withdrawal using the influence function technique

Energy Technology Data Exchange (ETDEWEB)

Triplett, T; Yurchak, D [Twin Cities Research Center, Bureau of Mines, US Dept. of the Interior, Minneapolis, MN (United States)

1997-12-31

This paper presents research, conducted by the Bureau of Mines, on modifying the influence function method to predict subsidence. According to theory, this technique must incorporate an intensity function to represent the relative significance of the causes of subsidence. This paper shows that the inclusion of a reasonable intensity function increases the accuracy of the technique, then presents the required functions for case studies of longwall coal mining subsidence in Illinois, USA, potash mining subsidence in new Mexico, USA, and subsidence produced by ground water withdrawal in California, USA. Finally, the paper discusses a method to predict the resultant strain from a simply measured site constant and ground curvatures calculated by the technique. (orig.)

Determination of intensity functions for predicting subsidence from coal mining, potash mining, and groundwater withdrawal using the influence function technique

Energy Technology Data Exchange (ETDEWEB)

Triplett, T.; Yurchak, D. [Twin Cities Research Center, Bureau of Mines, US Dept. of the Interior, Minneapolis, MN (United States)

1996-12-31

This paper presents research, conducted by the Bureau of Mines, on modifying the influence function method to predict subsidence. According to theory, this technique must incorporate an intensity function to represent the relative significance of the causes of subsidence. This paper shows that the inclusion of a reasonable intensity function increases the accuracy of the technique, then presents the required functions for case studies of longwall coal mining subsidence in Illinois, USA, potash mining subsidence in new Mexico, USA, and subsidence produced by ground water withdrawal in California, USA. Finally, the paper discusses a method to predict the resultant strain from a simply measured site constant and ground curvatures calculated by the technique. (orig.)

Origin of acid mine drainage in Enugu

International Nuclear Information System (INIS)

Uma, K.O.

1992-01-01

Mine flooding is a serious problem in the Enugu Coal Mines and has led to the abandonment of two of the four mines. About 1800 m 3 of water is pumped out daily from the mines into the nearby streams. The source of this enormous volume of water has been established based on the hydrodynamics and hydrology of the area. Two prolific aquifers - an unconfined and a confined system - overlie the mines, but the mine water is derived principally from the unconfined aquifer. The pathway of flow is, provided by the numerous fractures connecting the two aquifers and the mine tunnel. The major hydrochemical activity resulting in pollution of the mine water occurs within the sumps in the floor of the longwalls. These sumps act as oxidation chambers where groundwater from the fractures mixes and subsequently reacts with sulfur-rich solutes released by coal mining. Contrary to general belief, the mine drainage has not seriously degraded the chemistry of receiving streams. The pH and electric conductivity, representing, the dissolved ions, were increased less than 10% of the values in the unaffected region

Study of behaviour of workings in longwall panel based on field instrumentation

Energy Technology Data Exchange (ETDEWEB)

V.R. Sastry; Roshan Nair [National Institute of Technology Karnataka, Mangalore (India). Department of Mining Engineering

2009-07-01

The paper presents field monitoring study of two adjacent longwall panels based on stress measurements in longwall block and barrier, load transferred on to the gate roads and convergence measurements in the gate roads during face retreat in the panels. Results indicated that the section of barrier lying in the goaf experienced higher abutment stress when compared with the section lying ahead of face. There was a transfer of load in gate roads ahead of face after the occurrence of roof fall in goaf. Maximum cumulative convergence of more than 8 mm was observed in the gate roads during weightings.

Supporting of mine workings and design of support systems. Madenlerde tahkimat isleri ve tasarmi

Energy Technology Data Exchange (ETDEWEB)

Biron, C; Arioglu, E; (Istanbul Teknik Universitesi, Maden Fakultesi)

1980-01-01

This article deals with elements of elasticity in rocks and examines the engineering properties of rocks. It includes stress distributions around mine openings and deformations of mine openings. Strata control concept in coal mining is explained. Support systems in stone drifts, gateways, shafts and longwalls are discussed; timber supports, steel arches, articulated arches, roof bolting, concrete supports, supports on mechanized faces are detailed. Emphasis is placed upon engineering properties of materials of support systems. The design concepts of mine support systems are described. The objects of the design are expressed with several numerical examples. It concludes with stowing: pneumatic stowing, and hydraulic stowing in metal and coal mining.

Determination of Abutment Pressure in Coal Mines with Extremely Thick Alluvium Stratum: A Typical Kind of Rockburst Mines in China

Science.gov (United States)

Zhu, Sitao; Feng, Yu; Jiang, Fuxing

2016-05-01

This paper investigates the abutment pressure distribution in coal mines with extremely thick alluvium stratum (ETAS), which is a typical kind of mines encountering frequent intense rockbursts in China. This occurs due to poor understanding to abutment pressure distribution pattern and the consequent inappropriate mine design. In this study, a theoretical computational model of abutment pressure for ETAS longwall panels is proposed based on the analysis of load transfer mechanisms of key stratum (KS) and ETAS. The model was applied to determine the abutment pressure distribution of LW2302S in Xinjulong Coal Mine; the results of stress and microseismic monitoring verified the rationality of this model. The calculated abutment pressure of LW2302S was also used in the terminal mining line design of LW2301N for rockburst prevention, successfully protecting the main roadway from the adverse influence of the abutment pressure.

Releveling and behavior of strap-retrofitted damaged test foundations exposed to mine subsidence

International Nuclear Information System (INIS)

Marino, G.G.

1997-01-01

Test foundation walls were constructed in an area of planned subsidence. These crawl space-sized block bearing walls were located in the tension zone of a longwall panel. The test walls were 1.2 m (40 ft) long and were vertically loaded on top with soil binds to simulate the weight of a house. As the longwall proceeded past these test foundations, subsidence movements damaged the test structures. These damaged foundations were then structurally and aesthetically repaired by using a steel strap retrofit and applying a cementitious surface coating. The repaired test foundations underwent significant subsequent subsidence as an adjacent longwall was mined beneath. The response of the repaired foundation is summarized in this paper. The steel straps were also used to relevel another set of the test foundations after they were tilted and damaged by subsidence. First, the straps were applied to the block bearing walls, and then wall jacks were used to lift the upper portion of the walls to a level position. This releveling procedure is outlined with the results

Economic aspects of comprehensive mechanization of mining operations. [Poland

Energy Technology Data Exchange (ETDEWEB)

Zemla, F

1978-02-01

The development of mining equipment for longwall mining and effects of mechanization of mining operations on labor productivity and output of underground coal mines in Poland from 1950 to 1976 are discussed. Mining equipment used from 1950 to 1960 (cutters, steel or timber supports, chain conveyors, drilling and blasting), from 1960 to 1970 (cutter loaders, chain conveyors and steel supports), from 1970 to 1976 (shearer loaders, chain conveyors and powered or shield supports) is analyzed. Coal output of faces mined by mechanized equipment increased from 9.7% in 1950 to 63.1% in 1969 and to 87.6% of total coal output in 1976. The total coal output of underground coal mines increased from 99.1 Mt in 1959 to 125.0 Mt in 1969 and 179.3 Mt in 1976. Labor productivity per miner increased from 1.561 t/d in 1959 to 2.529 t/d in 1969 and to 3.433 t/d in 1976.

Mechanised packing for longwall coal faces. Monolithic packing and powered supports for the packhole

Energy Technology Data Exchange (ETDEWEB)

Carr, F; Kitching, F

1978-11-01

If full advantage is to be taken of the great advances that have taken place in power loading and powered support at the coalface, other operations in that vicinity must be similarly mechanised and automated. The gateside packing is one of the most important of these ancillary operations on the longwall face, and in previous articles F. Carr and F. Kitching, National Coal Board Headquarters, Coalface Operations Mining Engineers have given a very comprehensive resume of the present situation. Subjects covered include the requirements of mechanised packing, the parameters involved, the various working arrangements, the different systems of gate-ends, the types of equipment that are being used, their characteristics, the spread of their application, and the results obtained from them. In this article the authors conclude their survey by dealing with dirt/cement and anhydrite packing, by taking a hard look at powered supports for the packhole, and by expressing their views on the way mechanised packing may be expected to develop in the future.

The state of hydraulic mining in China and suggestions for future development

Energy Technology Data Exchange (ETDEWEB)

Anon, A.

1996-11-01

This paper discusses the state of development of hydraulic mining technology in China. The paper conceives that the seam conditions most suitable for hydraulic mining are: geologic faults with many cuts, inclined or gradually inclined thick and very thick seams with stable or moderately stable roofs, where longwall mining cannot be employed or pushed far; inclined or steeply inclined strata of inclination angle above 30{degree} with moderately stable roof, where the roof is stable or moderately stable, the inclination angle is greater than 7{degree}, with irregular production pattern and great variation in the seam thickness, or medium to thick coal seam of relatively more geologic damages and poor stability. Some suggestions are proposed for the future development of hydraulic mining.

Forecast and Prevention of Coal and Gas Outbursts in the Case of Application of a New Mining Method - Drilling of a Coal Pillar

Directory of Open Access Journals (Sweden)

Vlastimil Hudeček

2010-10-01

Full Text Available Coal and gas outbursts are one of risk factors accompanying the mining of coal in low seams in the Ostrava-Karviná Coalfield.At the use of the method of longwall mining, all coal reserves have not been mined out owing to tectonic faults. For mining outthe residual reserves, the application of a new mining method - drilling of a coal pillar was proposed.The method of mining of a coal seam utilizing long large diameter boreholes is verified in the Paskov Mine (company OKD, JSC –Czech Republic under conditions of rock mass with hazard of rock and gas outbursts in localities of residual pillars left in seams afterfinishing the mining operations performed with using the classical method of longwall working along the strike. [5]Forecast and preventive measures applied to the verification of the new method were based on previous experience withthe mining of seams with hazard of coal and gas outbursts. They accepted fully valid legislation, i.e. Ordinance of Ostrava RegionalMining Authority No. 3895/2002 and supplementary materials (Instructions and Guidelines. The proposed measures respectedthe character of the method being verified. [4]For all areas being mined, projects containing also chapters specifying the problems of ensuring the safety of mining worksand operation under conditions of hazard of coal and gas outbursts were prepared.In the contributions, basic proposals for the principles of coal and gas outburst forecast and prevention when applying the newmining method – drilling of a coal pillar are presented

Probabilistic modeling using bivariate normal distributions for identification of flow and displacement intervals in longwall overburden

Energy Technology Data Exchange (ETDEWEB)

Karacan, C.O.; Goodman, G.V.R. [NIOSH, Pittsburgh, PA (United States). Off Mine Safety & Health Research

2011-01-15

Gob gas ventholes (GGV) are used to control methane emissions in longwall mines by capturing it within the overlying fractured strata before it enters the work environment. In order for GGVs to effectively capture more methane and less mine air, the length of the slotted sections and their proximity to top of the coal bed should be designed based on the potential gas sources and their locations, as well as the displacements in the overburden that will create potential flow paths for the gas. In this paper, an approach to determine the conditional probabilities of depth-displacement, depth-flow percentage, depth-formation and depth-gas content of the formations was developed using bivariate normal distributions. The flow percentage, displacement and formation data as a function of distance from coal bed used in this study were obtained from a series of borehole experiments contracted by the former US Bureau of Mines as part of a research project. Each of these parameters was tested for normality and was modeled using bivariate normal distributions to determine all tail probabilities. In addition, the probability of coal bed gas content as a function of depth was determined using the same techniques. The tail probabilities at various depths were used to calculate conditional probabilities for each of the parameters. The conditional probabilities predicted for various values of the critical parameters can be used with the measurements of flow and methane percentage at gob gas ventholes to optimize their performance.

Comparison of Methane Control Methods in Polish and Vietnamese Coal Mines

Science.gov (United States)

Borowski, Marek; Kuczera, Zbigniew

2018-03-01

Methane hazard often occurs in hard coal mines and causes very serious accidents and can be the reason of methane or methane and coal dust explosions. History of coal mining shows that methane released from the rock mass to the longwall area was responsible for numerous mining disasters. The main source of methane are coal deposits because it is autochthonous gas and is closely related with carbonification and forming of coal deposits. Degree of methane saturation in coal deposits depends on numerous factors; mainly on presence or lack of insulating layers in cover deposit that allow or do not on degasification and easily methane outflow into surroundings. Hence in coal mining there are coal deposits that contain only low degree of methane saturation in places where is lack of insulating layers till high in methane coal deposits occurring in insulating claystones or in shales. Conducting mining works in coal deposits of high methane hazard without using of special measures to combat (ventilation, methane drainage) could be impossible. Control of methane hazard depends also on other co-occuring natural dangers for which used preventive actions eliminate methane hazard. Safety in mines excavating coal deposits saturated with methane depends on the correct estimation of methane hazard, drawn up forecasts, conducted observations, hazard control as well as undertaken prevention measures. Methane risk prevention includes identification and control methods of methane hazards as well as means of combating the explosive accumulation of methane in longwall workings. The main preventive actions in underground coal mines are: effective ventilation that prevents forming of methane fuses or placed methane accumulation in headings ventilated by airflow created by main fans and in headings with auxiliary ventilation, methane drainage using drain holes that are drilled from underground headings or from the surface, methanometry control of methane concentration in the air; location

Comparison of Methane Control Methods in Polish and Vietnamese Coal Mines

Directory of Open Access Journals (Sweden)

Borowski Marek

2018-01-01

Full Text Available Methane hazard often occurs in hard coal mines and causes very serious accidents and can be the reason of methane or methane and coal dust explosions. History of coal mining shows that methane released from the rock mass to the longwall area was responsible for numerous mining disasters. The main source of methane are coal deposits because it is autochthonous gas and is closely related with carbonification and forming of coal deposits. Degree of methane saturation in coal deposits depends on numerous factors; mainly on presence or lack of insulating layers in cover deposit that allow or do not on degasification and easily methane outflow into surroundings. Hence in coal mining there are coal deposits that contain only low degree of methane saturation in places where is lack of insulating layers till high in methane coal deposits occurring in insulating claystones or in shales. Conducting mining works in coal deposits of high methane hazard without using of special measures to combat (ventilation, methane drainage could be impossible. Control of methane hazard depends also on other co-occuring natural dangers for which used preventive actions eliminate methane hazard. Safety in mines excavating coal deposits saturated with methane depends on the correct estimation of methane hazard, drawn up forecasts, conducted observations, hazard control as well as undertaken prevention measures. Methane risk prevention includes identification and control methods of methane hazards as well as means of combating the explosive accumulation of methane in longwall workings. The main preventive actions in underground coal mines are: effective ventilation that prevents forming of methane fuses or placed methane accumulation in headings ventilated by airflow created by main fans and in headings with auxiliary ventilation, methane drainage using drain holes that are drilled from underground headings or from the surface, methanometry control of methane concentration in

DETERMINATION OF THE ZONE ENDANGERED BY METHANE EXPLOSION IN GOAF WITH CAVING OF LONGWALLS VENTILATED ON „Y” SYSTEM

Directory of Open Access Journals (Sweden)

Jarosław BRODNY

2016-10-01

Full Text Available One of the most dangerous and most commonly present risks in hard coal mines is methane hazard. During exploitation by longwall system with caving, methane is emitted to mine heading from the mined coal and coal left in a pile. A large amount of methane also flows from neighboring seams through cracks and fissures formed in rock mass. In a case of accumulation of explosive methane concentration in goaf zone and with appropriate oxygen concentration and occur-rence of initials (e.g. spark or endogenous fire, it may come to the explosion of this gas. In the paper there are present-ed results of numerical analysis of mixture of air and methane streams flow through the real heading system of a mine, characterized by high methane hazard. The aim of the studies was to analyze the ventilation system of considered head-ing system and determination of braking zones in goaf zone, in which dangerous and explosive concertation of methane can occur with sufficient oxygen concentration equal to at least 12%. Determination of position of these zones is neces-sary for the selection of appropriate parameters of the ventilation system to ensure safety of the crew. Analysis of the scale of methane hazard allows to select such a ventilation system of exploitation and neighboring headings that ensures chemical composition of mining atmosphere required by regulation, and required efficiency of methane drainage. The obtained results clearly show that numerical methods, combined with the results of tests in real conditions can be suc-cessfully used for the analysis of variants of processes related to ventilation of underground mining, and also in the anal-ysis of emergency states.

Dust-control for thick-seam wall mines.

CSIR Research Space (South Africa)

Belle, BK

2002-02-01

Full Text Available configuration and the belt curtains on the shearer. 3. Install, and evaluate the efficiency of, the physical shield curtains (conveyor belt or other flexible material) hanging from the shield structure inside the shield leg area at every 4th shield to reduce... and 1997, coal production hovered around the 50 million tonnes-a-year level (UK DTI, 2001). Currently, there are 16 producing underground mines in the UK, which includes 15 longwall faces, face lengths range from 250 m to 300 m (Creedy, 2001). Most...

Availability analysis of selected mining machinery

Directory of Open Access Journals (Sweden)

Brodny Jarosław

2017-06-01

Full Text Available Underground extraction of coal is characterized by high variability of mining and geological conditions in which it is conducted. Despite ever more effective methods and tools, used to identify the factors influencing this process, mining machinery, used in mining underground, work in difficult and not always foreseeable conditions, which means that these machines should be very universal and reliable. Additionally, a big competition, occurring on the coal market, causes that it is necessary to take action in order to reduce the cost of its production, e.g. by increasing the efficiency of utilization machines. To meet this objective it should be pro-ceed with analysis presented in this paper. The analysis concerns to availability of utilization selected mining machinery, conducted using the model of OEE, which is a tool for quantitative estimate strategy TPM. In this article we considered the machines being part of the mechanized longwall complex and the basis of analysis was the data recording by the industrial automation system. Using this data set we evaluated the availability of studied machines and the structure of registered breaks in their work. The results should be an important source of information for maintenance staff and management of mining plants, needed to improve the economic efficiency of underground mining.

Modeling stress–strain state of rock mass under mining of complex-shape extraction pillar

Science.gov (United States)

Fryanov, VN; Pavlova, LD

2018-03-01

Based on the results of numerical modeling of stresses and strains in rock mass, geomechanical parameters of development workings adjacent to coal face operation area are provided for multi-entry preparation and extraction of flat seams with production faces of variable length. The negative effects on the geomechanical situation during the transition from the longwall to shortwall mining in a fully mechanized extraction face are found.

75 FR 81313 - Petitions for Modification of Existing Mandatory Safety Standards

Science.gov (United States)

2010-12-27

... every 7 days, due to adverse roof, rock falls, and floor heave conditions in the return entry in the C... continuing mining cycle; (2) the longwall development panels consist of a three-entry system with 275-foot... being developed at the mine as part of a continuing mining cycle; (2) the longwall development panels...

Maximal loads acting on legs of powered roof support unit in longwalls with bumping hazards

Institute of Scientific and Technical Information of China (English)

Stanislaw Szweda

2001-01-01

In the article the results of measurements of the resultant force in th e legs of a powered roof support unit, caused by a dynamic interaction of the ro ck mass, are discussed. The measurements have been taken in the longwalls mined with a roof fall, characterized by the highest degree of bumping hazard. It has been stated that the maximal force in the legs Fm, recorded during a dynam ic interaction of the rock mass, is proportional to the initial static force in the legs Fst,p. Th erefore a need for a careful selection of the initial load of the powered roof s upport, according to the local mining and geological conditions, results from su ch a statement. Setting the legs with the supporting load exceeding the indispen sable value for keeping the direct roof solids in balance, deteriorating the ope rational parameters of a longwall system also has a disadvantageous influence on the value of the force in the legs and the rate of its increase, caused by a dy namic interaction of the rock mass. A correct selection of the initial load caus es a decrease in the intensity of a dynamic interaction of the rock mass on powe red roof supports, which also has an advantageous influence on their life. 　　Simultaneously with the measurements of the resultant force in the legs, the vertical acceleration of the canopy was also recorded. It has enabled to prove that the exte rnal dynamic forces may act on the unit both from the roof as well as from the f loor. The changes of the force in the legs caused by dynamic phenomena intrinsic ally created in the roof and changes of the force in the legs caused by blasting explosives in the roof of the working, have been analyzed separately. It has been stated that an increase in the loads of legs, caused by intrinsi c phenomena is significantly higher than a force increase in the legs caused by blasting. It means that powered roof supports, to be operated in the workings, w here the bumping hazard occurs, will also transmit the loads

A jewel in the desert: BHP Billiton's San Juan underground mine

Energy Technology Data Exchange (ETDEWEB)

Buchsbaum, L.

2007-12-15

The Navajo Nation is America's largest native American tribe by population and acreage, and is blessed with large tracks of good coal deposits. BHP Billiton's New Mexico Coal Co. is the largest in the Navajo regeneration area. The holdings comprise the San Juan underground mine, the La Plata surface mine, now in reclamation, and the expanding Navajo surface mine. The article recounts the recent history of the mines. It stresses the emphasis on sensitivity to and helping to sustain tribal culture, and also on safety. San Juan's longwall system is unique to the nation. It started up as an automated system from the outset. Problems caused by hydrogen sulfide are being tackled. San Juan has a bleederless ventilation system to minimise the risk of spontaneous combustion of methane and the atmospheric conditions in the mine are heavily monitored, especially within the gob areas. 3 photos.

The upper pennsylvanian pittsburgh coal bed: Resources and mine models

Science.gov (United States)

Watson, W.D.; Ruppert, L.F.; Tewalt, S.J.; Bragg, L.J.

2001-01-01

The U.S. Geological Survey recently completed a digital coal resource assessment model of the Upper Pennsylvanian Pittsburgh coal bed, which indicates that after subtracting minedout coal, 16 billion short tons (14 billion tonnes) remain of the original 34 billion short tons (31 billion tonnes) of coal. When technical, environmental, and social restrictions are applied to the remaining Pittsburgh coal model, only 12 billion short tons (11 billion tonnes) are available for mining. Our assessment models estimate that up to 0.61 billion short tons (0.55 billion tonnes), 2.7 billion short tons (2.4 billion tonnes), and 8.5 billion short tons (7.7 billion tonnes) could be available for surface mining, continuous mining, and longwall mining, respectively. This analysis is an example of a second-generation regional coal availability study designed to model recoverability characteristics for all the major coal beds in the United States. ?? 2001 International Association for Mathematical Geology.

On-Site Radon Detection of Mining-induced Fractures from Overlying Strata to the Surface: A Case Study of the Baoshan Coal Mine in China

Directory of Open Access Journals (Sweden)

Wei Zhang

2014-12-01

Full Text Available Large-scale longwall mining of shallow coal seams may cause mining-induced fractures that can project completely through to the surface. This could lead to a series of mine safety and environmental issues, further deteriorating the already fragile ecological environment in the Western mining areas in China. Therefore, an accurate and effective understanding of the spatiotemporal evolution law of mining-induced fractures in overlying strata and its relationship to upper aquifers is critical. In this paper, the application of the geophysical-chemical properties of radon in mining engineering is explored as a potential solution to the shortcomings of existing surveying methods. A radioactive measurement method is proposed for the detection of the development of mining-induced fractures from overlying strata to the surface in the Baoshan Coal Mine (BCM. The on-site test indicated that the first weighting step is approximately 60 m, the average periodic weighting step is approximately 20 m, and the influence coverage of the advanced abutment pressure is approximately 30 m. The presented method could be used as an indirect technical support to increase the safety of coal mining by acting as a simple, fast, and reliable method of detecting mining-induced fractures in overlying strata.

Mechanization of operations in underground workings in coal mines and research project trends. [Poland

Energy Technology Data Exchange (ETDEWEB)

Reich, K; Skoczynski, W; Sikora, W

1985-01-01

Structure of black coal reserves of Poland, imported and Polish made equipment for underground mining, prospects for mechanization of selected operations in underground mines and research programs of the KOMAG Center for Mechanization of Mining are evaluated. Prospects for longwall mining with caving or stowing in thick coal seams (slice mining), thin (0.8 to 1.2 m), level or inclined coal seams and steep seams are analyzed. The following equipment for mechanization of underground mining is evaluated: integrated face systems, shearer loaders, chain conveyors, belt conveyors, coal plows, equipment for mine drivage, hoists, drive systems for mining equipment. The following research programs of the KOMAG Center are reviewed: modernization of face systems for coal seams with uncomplicated mining conditions, development of equipment for thin seam mining, development of types of mining equipment for coal seams from 1.5 to 3.0 m thick with dip angles to 25 degrees, modernization of equipment for thick seam mining, increasing efficiency of mine drivage (new types of heading machines, materials handling equipment for mine drivage), mechanization of auxiliary operations in underground coal mines, improving quality of mining equipment, development of equipment for coal preparation, increasing occupational safety in underground mining.

Mining aspects of hard to access oil sands deposits

Energy Technology Data Exchange (ETDEWEB)

Stephenson, G.; Wright, D.; Lukacs, Z. [Norwest Corp., Calgary, AB (Canada)

2006-07-01

While a variety of oil sands mining technologies have been explored since the 1960s, the oil sands industry has generally favoured truck and shovel mining as a proven, low-cost mining solution. However, surface mining economics are affected by the price of bitumen, haul distances, tailings storage and geotechnical constraints. Maintenance, labour and the cost of replacing tires and ground engaging tools also have a significant impact on the economics of surface mining. Large volumes of water are used in surface mining, and remediation of surface mined areas can take hundreds of years. Damage to machinery is common as oil sands are abrasive and adhere to equipment. This presentation examined recent technologies developed to improve the economics of surface mining. Various extraction and tailings technologies were reviewed. Issues concerning the integration of mining and extraction processes were discussed. Various monitoring tools were evaluated. A review of new underground mining options included outlines of: longwall mining; sub-level caving; tunnel boring; and room and pillar extraction techniques. A generalized regional geology was presented. It was concluded that the oil sands surfacing mining industry should concentrate on near-term research needs to improve the performance and economics of proven technologies. Screening studies should also be conducted to determine the focus for the development of underground technologies. refs., tabs., figs.

The forecasting method of rock-burst and the application based on overlying multi-strata spatial structure theory

Energy Technology Data Exchange (ETDEWEB)

Cun-Wen Wang; Fu-Xing Jiang; Qing-Guo Sun; Chun-Jiang Sun; Ming Zhang; Zhen-Wen Ji; Xiu-Feng Zhang [University of Science and Technology, Beijing, Beijing (China). Civil & Environmental Engineering School

2009-02-15

Based on the overlying multi-strata spatial structure theory and mechanical analysis, the paper discusses the relationship between 'S' shape spatial strata structure movement and mining stress distribution. Coal out-burst forecasting based on 'S' shape spatial strata structure movement was studied. Microseismic monitoring in Huafeng Coal Mine in Shandong Province showed that coal out-burst will ocur when the advancing distance of the longwall face is equal to one, two or three times the length of the longwall face respectively. During these periods, the mined areas approach to square shape while the 'S' shape spatial strata structure acts strongly. Based on this, the time and position of coal out-burst in No. 1410 longwall face of Huafeng Coal Mine was predicted. By using large diameter and deep drill holes in the coal seam and deep drill holes with blasting in the roof at those danger areas, the No. 1410 longwall face safely advanced through those danger areas. During those periods the microseismic monitoring system detected very strong mine quakes. 15 refs., 1 fig., 2 tabs.

Application of Elements of TPM Strategy for Operation Analysis of Mining Machine

Science.gov (United States)

Brodny, Jaroslaw; Tutak, Magdalena

2017-12-01

Total Productive Maintenance (TPM) strategy includes group of activities and actions in order to maintenance machines in failure-free state and without breakdowns thanks to tending limitation of failures, non-planned shutdowns, lacks and non-planned service of machines. These actions are ordered to increase effectiveness of utilization of possessed devices and machines in company. Very significant element of this strategy is connection of technical actions with changes in their perception by employees. Whereas fundamental aim of introduction this strategy is improvement of economic efficiency of enterprise. Increasing competition and necessity of reduction of production costs causes that also mining enterprises are forced to introduce this strategy. In the paper examples of use of OEE model for quantitative evaluation of selected mining devices were presented. OEE model is quantitative tool of TPM strategy and can be the base for further works connected with its introduction. OEE indicator is the product of three components which include availability and performance of the studied machine and the quality of the obtained product. The paper presents the results of the effectiveness analysis of the use of a set of mining machines included in the longwall system, which is the first and most important link in the technological line of coal production. The set of analyzed machines included the longwall shearer, armored face conveyor and cruscher. From a reliability point of view, the analyzed set of machines is a system that is characterized by the serial structure. The analysis was based on data recorded by the industrial automation system used in the mines. This method of data acquisition ensured their high credibility and a full time synchronization. Conclusions from the research and analyses should be used to reduce breakdowns, failures and unplanned downtime, increase performance and improve production quality.

Analysis of Mining-induced Valley Closure Movements

Science.gov (United States)

Zhang, C.; Mitra, R.; Oh, J.; Hebblewhite, B.

2016-05-01

Valley closure movements have been observed for decades in Australia and overseas when underground mining occurred beneath or in close proximity to valleys and other forms of irregular topographies. Valley closure is defined as the inward movements of the valley sides towards the valley centreline. Due to the complexity of the local geology and the interplay between several geological, topographical and mining factors, the underlying mechanisms that actually cause this behaviour are not completely understood. A comprehensive programme of numerical modelling investigations has been carried out to further evaluate and quantify the influence of a number of these mining and geological factors and their inter-relationships. The factors investigated in this paper include longwall positional factors, horizontal stress, panel width, depth of cover and geological structures around the valley. It is found that mining in a series passing beneath the valley dramatically increases valley closure, and mining parallel to valley induces much more closure than other mining orientations. The redistribution of horizontal stress and influence of mining activity have also been recognised as important factors promoting valley closure, and the effect of geological structure around the valley is found to be relatively small. This paper provides further insight into both the valley closure mechanisms and how these mechanisms should be considered in valley closure prediction models.

System principles and evaluation criteria of reliability for optimization of technological parameters of coal deposits

Directory of Open Access Journals (Sweden)

A.О. Khorolskiy

2017-12-01

Full Text Available The article deals with solving the scientific problem of select mining equipment for selection longwall faces of mining venture. The main goal of the paper is to study technology of coal extraction of mining venture. The paper proposes a new approach to solve a problem of mining equipment selection for longwall faces of mining venture. The article describes new method for selection of mining equipment based on theory graph. Special attention is given to technological aspects; they are lenght of longwall faces, depth of coal stratum. Predictions obtained for daily production of mining equipment are compared with design outputs. Conclusions regarding the main reason of instability of longwall faces workings are made. It is found that to be able to use standard algorithms find the shortest path between vertices, you must perform matrix description of the constructed graphs that illustrate the structure of the interaction of different types of control equipment. Using classical optimization of method of discrete mathematics and algorithms for finding the shortest path between two vertices of network models obtained from the formalization of graphs with maximum results of specific types of equipment production chains, solved the problem of rational choice cleaning equipment for the new site with the cost parameters of the mining equipment and cost of mining coal. The authors developed effective and appropriate variants for the mine development for different coal deposits of mining venture.

Method of gas emission control for safe working of flat gassy coal seams

Science.gov (United States)

Vinogradov, E. A.; Yaroshenko, V. V.; Kislicyn, M. S.

2017-10-01

The main problems at intensive flat gassy coal seam longwall mining are considered. For example, mine Kotinskaja JSC “SUEK-Kuzbass” shows that when conducting the work on the gassy coal seams, methane emission control by means of ventilation, degassing and insulated drain of methane-air mixture is not effective and stable enough. It is not always possible to remove the coal production restrictions by the gas factor, which leads to financial losses because of incomplete using of longwall equipment and the reduction of the technical and economic indicators of mining. To solve the problems, the authors used a complex method that includes the compilation and analysis of the theory and practice of intensive flat gassy coal seam longwall mining. Based on the results of field and numerical researches, the effect of parameters of technological schemes on efficiency of methane emission control on longwall panels, the non-linear dependence of the permissible according to gas factor longwall productivity on parameters of technological schemes, ventilation and degassing during intensive mining flat gassy coal seams was established. The number of recommendations on the choice of the location and the size of the intermediate section of coal heading to control gassing in the mining extracted area, and guidelines for choosing the parameters of ventilation of extracted area with the help of two air supply entries and removal of isolated methane-air mixture are presented in the paper. The technological scheme, using intermediate entry for fresh air intake, ensuring effective management gassing and allowing one to refuse from drilling wells from the surface to the mined-out space for mining gas-bearing coal seams, was developed.

Effects of natural conditions on development of a landslide at a mining area

Energy Technology Data Exchange (ETDEWEB)

Palki, J

1982-01-01

Investigations show that 39.4% of landslides at the mining ground in the Rybnik coal region is caused by factors other than underground mining. Determining the actual cause of a landslide is of importance for an underground mine because, as a rule, all ground damage is claimed to be caused by underground mining. A case of a landslide in the Rybnik area is analyzed. Landslide development is shown in a photo and 17 schemes. Ground morphology, water conditions and effects of underground longwall mining are evaluated. The analyses show that ground subsidence caused by underground mining ranging from 2.0 m to 3.1 m reduced the angle of slope inclination preventing more intensive landslides. Intensity of horizontal deformation was too low to cause a landslide. Slope stability decrease was caused by loose rock layers (sands) at the base of a hill. Accumulation of atmospheric precipitation and disturbed water outflow caused an increase in the plasticity of the sand. Mechanical vibrations caused by train traffic on tracks located close to the slope were an additional factor causing landslide development. (6 refs.)

Possibility of increasing intensity of mining by mechanization with use of shearer loaders

Energy Technology Data Exchange (ETDEWEB)

Sikora, W; Jaszczuk, M

1981-10-01

Discusses methods of increasing productivity of face systems in longwall mining. Feasibility of increasing coal output by variation of shearer loader haulage speed is analyzed. Effects of haulage speed variation on energy consumption or cutting tool wear are not considered. It is assumed that haulage speed does not depend on advance rate of the powered supports or the rate of face conveyor advance. Mathematical equations are derived for calculation of the optimum haulage speed variations. The method consists in use of variable haulage speed optimized for a given section of a longwall face without overloading the conveyor drive system. Situations with single drum shearer loaders and with bi-directional shearer loaders with cutting drums situated at both ends of the shearer are analyzed. Analyses show that by haulage speed variation shearer loader productivity is significantly increased. Performance tests under operational conditions show that in the case of a bi-directional shearer loader productivity increases by 31% and in the case of a shearer loader with a single drum by 11%. (4 refs.) (In Polish)

Twentieth anniversary of the fusion of the Wanda-Lech and Pokoj mines at Ruda Slaska

Energy Technology Data Exchange (ETDEWEB)

Pisarek, P.; Baranowski, Z.; Maczka, a.; Kowalski, Z.

1988-10-01

Presents the history of the Wanda-Lech and Pokoj mines until 1968 when they were fused, and development, technical progress and investment in the mines since 1968. Application of longwall equipment sets dates from 1965. The index of powered winning has reached 93.7% and that of powered loading - 97.4%. Seismoacoustic (1970/71) and microseismologic (1974) monitoring stations have been put into operation. The following investments have been realized since 1968: the main shaft Wanda and auxiliary shaft Lech II, two winning horizons, 3 main ventilation fans, a coal preparation plant, a bathhouse for 2,650 and a boiler house fuelled with run-of-mine methane. Mine communications, rail transport and storage facilitites have been modernized and extended. The mining area of the present Pokoj mine is shown in a scheme. Production before and after the take-over is compared: production increased from 1.969121 Mt in 1968 to 2.434740 Mt in 1987. A rehabilitation center (physical therapy, inhalation kinesthesia, hydrotherapy) cares for 2,000 patients annually. Further social services and facilities provided for the miners are described.

VRLane: a desktop virtual safety management program for underground coal mine

Science.gov (United States)

Li, Mei; Chen, Jingzhu; Xiong, Wei; Zhang, Pengpeng; Wu, Daozheng

2008-10-01

VR technologies, which generate immersive, interactive, and three-dimensional (3D) environments, are seldom applied to coal mine safety work management. In this paper, a new method that combined the VR technologies with underground mine safety management system was explored. A desktop virtual safety management program for underground coal mine, called VRLane, was developed. The paper mainly concerned about the current research advance in VR, system design, key techniques and system application. Two important techniques were introduced in the paper. Firstly, an algorithm was designed and implemented, with which the 3D laneway models and equipment models can be built on the basis of the latest mine 2D drawings automatically, whereas common VR programs established 3D environment by using 3DS Max or the other 3D modeling software packages with which laneway models were built manually and laboriously. Secondly, VRLane realized system integration with underground industrial automation. VRLane not only described a realistic 3D laneway environment, but also described the status of the coal mining, with functions of displaying the run states and related parameters of equipment, per-alarming the abnormal mining events, and animating mine cars, mine workers, or long-wall shearers. The system, with advantages of cheap, dynamic, easy to maintenance, provided a useful tool for safety production management in coal mine.

Controlling ventilation for safe escape from coal mine fires

Energy Technology Data Exchange (ETDEWEB)

Wala, A M [University of Kentucky, Lexington, KY (United States). Mining Engineering Dept.

1966-04-01

If a fire occurs outby an underground coal mine section, the immediate safe evacuation of miners from the working section should always take precedence. Unfortunately, in many cases, the dedicated escapeway (escape routes) for the evacuation of the miners become contaminated by the byproducts of fire from the adjacent entries. The purpose of this paper is to present the ventilation-control process that would keep the escapeway free from contaminants and, thus, available for travel. A few scenarios of mine fires in longwall development panels are analysed and discussed. To perform these studies, a mine-fire simulator (MFS) was used. This (MFS) provides a dynamic representation of the fire`s progress (in real time) and gives a color-graphic visualization of the spready of oxygen, combustion products and temperature of the gases throughout the ventilation system. Also presented and discussed are ways in which the MFS can be used as a training and teaching tool for miners and particularly, for ventilation and safety specialists. 7 refs., 10 figs.

Installation of a digital, wireless, strong-motion network for monitoring seismic activity in a western Colorado coal mining region

Energy Technology Data Exchange (ETDEWEB)

Peter Swanson; Collin Stewart; Wendell Koontz [NIOSH, Spokane, WA (USA). Spokane Research Laboratory

2007-01-15

A seismic monitoring network has recently been installed in the North Fork Valley coal mining region of western Colorado as part of a NIOSH mine safety technology transfer project with two longwall coal mine operators. Data recorded with this network will be used to characterize mining related and natural seismic activity in the vicinity of the mines and examine potential hazards due to ground shaking near critical structures such as impoundment dams, reservoirs, and steep slopes. Ten triaxial strong-motion accelerometers have been installed on the surface to form the core of a network that covers approximately 250 square kilometers (100 sq. miles) of rugged canyon-mesa terrain. Spread-spectrum radio networks are used to telemeter continuous streams of seismic waveform data to a central location where they are converted to IP data streams and ported to the Internet for processing, archiving, and analysis. 4 refs.

Determination of Destress Blasting Effectiveness Using Seismic Source Parameters

Science.gov (United States)

Wojtecki, Łukasz; Mendecki, Maciej J.; Zuberek, Wacaław M.

2017-12-01

Underground mining of coal seams in the Upper Silesian Coal Basin is currently performed under difficult geological and mining conditions. The mining depth, dislocations (faults and folds) and mining remnants are responsible for rockburst hazard in the highest degree. This hazard can be minimized by using active rockburst prevention, where destress blastings play an important role. Destress blastings in coal seams aim to destress the local stress concentrations. These blastings are usually performed from the longwall face to decrease the stress level ahead of the longwall. An accurate estimation of active rockburst prevention effectiveness is important during mining under disadvantageous geological and mining conditions, which affect the risk of rockburst. Seismic source parameters characterize the focus of tremor, which may be useful in estimating the destress blasting effects. Investigated destress blastings were performed in coal seam no. 507 during its longwall mining in one of the coal mines in the Upper Silesian Coal Basin under difficult geological and mining conditions. The seismic source parameters of the provoked tremors were calculated. The presented preliminary investigations enable a rapid estimation of the destress blasting effectiveness using seismic source parameters, but further analysis in other geological and mining conditions with other blasting parameters is required.

THE ADOPTION OF THE ARCGIS SYSTEM TO SUPPORT THE ANALYSES OF THE INFLUENCE OF THE MINING TREMORS ON THE BUILDING OBJECTS

Directory of Open Access Journals (Sweden)

Violetta SOKOŁA-SZEWIOŁA

2016-10-01

Full Text Available Nowadays the mining companies use the Spatial Information System in order to facilitate data management, gathered during the mining activity. For these purposes various kinds of applications and software information are used. They allow for faster and easier data processing. In the paper there are presented the possibilities of using the ArcGIS system to support the tasks performed in the mining industry in the scope of the analysis of the influence of the mining tremors, induced by the longwall exploitation on the facilities construction sited on the surface area. These possibilities are presented by the example of the database developed for the coal mine KWK “Rydułtowy-Anna.” The developed database was created using ArcGIS software for Desktop 10. 1. It contains the values of parameters, specified for its implementation relevant to the analyses of the influence of the mining tremors on the surface structures.

Longwall mining and surface deformation – lessons learned from dInSAR measurements

CSIR Research Space (South Africa)

Engelbrecht, Jeanine

2016-08-01

Full Text Available including 1) subsidence related to mining and groundwater abstraction, 2) deformation following earthquake events, 3) monitoring of landslides and slope stability, 4) monitoring the stability of infrastructure and large engineering works, and 5) monitoring...

Coal mine subsidence: effects of mitigation on crop yields

International Nuclear Information System (INIS)

Darmody, R.G.; Hetzler, R.T.; Simmons, F.W.

1992-01-01

Subsidence from longwall underground coal mining adversely impacts agricultural land by creating wet or ponded areas. While most subsided areas show little impact, some localized places, usually less than 1.5 ha in size, may experience total crop failure. Coal companies mitigate subsidence damaged cropland by installing drainage waterways or by adding fill material to raise the grade. The objective of this study was to test the effectiveness of mitigation in restoring corn and soybean yields to pre-mined levels. Fourteen sites in southern Illinois were selected for study. Corn (Zea mays L.) and soybean (Glycine max L.) yields from mitigated and nearby undisturbed areas were compared for four years. Results varied due to differing weather and site conditions. Mean corn yields overall, however were significantly (α0.05) lower on mitigated areas. There was no significant difference in overall mean soybean yields. Soil fertility levels were similar and did not account for yield differences. 14 refs., 1 fig., 7 tabs

Inference of strata separation and gas emission paths in longwall overburden using continuous wavelet transform of well logs and geostatistical simulation

Science.gov (United States)

Karacan, C. Özgen; Olea, Ricardo A.

2014-06-01

Prediction of potential methane emission pathways from various sources into active mine workings or sealed gobs from longwall overburden is important for controlling methane and for improving mining safety. The aim of this paper is to infer strata separation intervals and thus gas emission pathways from standard well log data. The proposed technique was applied to well logs acquired through the Mary Lee/Blue Creek coal seam of the Upper Pottsville Formation in the Black Warrior Basin, Alabama, using well logs from a series of boreholes aligned along a nearly linear profile. For this purpose, continuous wavelet transform (CWT) of digitized gamma well logs was performed by using Mexican hat and Morlet, as the mother wavelets, to identify potential discontinuities in the signal. Pointwise Hölder exponents (PHE) of gamma logs were also computed using the generalized quadratic variations (GQV) method to identify the location and strength of singularities of well log signals as a complementary analysis. PHEs and wavelet coefficients were analyzed to find the locations of singularities along the logs. Using the well logs in this study, locations of predicted singularities were used as indicators in single normal equation simulation (SNESIM) to generate equi-probable realizations of potential strata separation intervals. Horizontal and vertical variograms of realizations were then analyzed and compared with those of indicator data and training image (TI) data using the Kruskal-Wallis test. A sum of squared differences was employed to select the most probable realization representing the locations of potential strata separations and methane flow paths. Results indicated that singularities located in well log signals reliably correlated with strata transitions or discontinuities within the strata. Geostatistical simulation of these discontinuities provided information about the location and extents of the continuous channels that may form during mining. If there is a gas

Discussion: some new findings from surface subsidence monitoring over longwall panels

International Nuclear Information System (INIS)

Luo, Y.; Peng, S.S.; Arioglu, E.

1992-01-01

The article consists of a discussion of the paper, 'some new findings from surface subsidence monitoring over longwall panels' and a reply by the paper's authors, Luo and Peng. The reviewer, Arioglu, regards the paper favourably but suggests that surface subsidence can be represented by an exponential expression, and that there is a regression equation linking possible subsidence, pillar loading and the height-to-width ratio of the pillars left. Luo and Peng reply with their reasons for preferring their original linear regression model to the non-linear models suggested by Arioglu. 4 figs

ANALYSIS OF THE POSSIBILITY OF INTEGRATING A MINING RIGHT-ANGLE PLANETARY GEARBOX WITH TECHNICAL DIAGNOSTICS SYSTEMS

Directory of Open Access Journals (Sweden)

Andrzej WIECZOREK

2016-12-01

Full Text Available A key factor enabling the achievement of the required capacity by longwall mining systems is to obtain a satisfactory service life for individual components of such systems. Such components include right-angle planetary gearboxes for armoured face conveyors. An increase in the service life of such equipment can be achieved by ensuring adequacy in terms of design, materials and organization. As a part of organizational changes, the use of individual diagnostics systems may have the greatest impact on the service life of mining gearboxes; however, their widespread implementation is limited by economic and operational barriers. This paper presents an analysis of the possibility of integrating mining gearboxes with electronic systems of technical diagnostics, as well as expanding the scope of the technical condition monitoring by the machines operating together with these gearboxes. As a result of the calculation and design work performed, it has been demonstrated that it is possible to integrate technical diagnostics systems with advanced data transmission capabilities inside gearboxes.

30 CFR 75.817 - Cable handling and support systems.

Science.gov (United States)

2010-07-01

... High-Voltage Longwalls § 75.817 Cable handling and support systems. Longwall mining equipment must be provided with cable-handling and support systems that are constructed, installed and maintained to minimize... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Cable handling and support systems. 75.817...

Planning design of Ukrainian mines by the means of numerical calculations

Energy Technology Data Exchange (ETDEWEB)

Ruppel, Ulrich; Scior, Carsten [DMT GmbH und Co. KG (DMT), Essen (Germany). Rock Mechanic Dept.

2008-08-21

Using a mine in the Ukraine as an example it is shown how the DMT performs rock mechanical and support planning or roadways in hard coal mines worldwide. Therefore it is necessary to analyse existing measurements and operating experience within a few days as well as organising further surveys on site on short notice. Based on these results the numerical models are calibrated. Using the numerical simulation technology it is possible for DMT to quantify and analyse the rock mechanical impact of different support systems within a short time. Finally the results of the numerical calculations are set in comparison in a rating matrix. Besides making a decision on implementing new roadway and support systems with the objective to use the roadways up to the second longwall panel, the rating matrix is also used for analysing the optimization potentials of existing support systems. This allows the recommendations to immediate improvement of the strata control in the miner's roadways. (orig.)

Coal mine subsidence: effects of mitigation on crop yields. [USA - Illinois

Energy Technology Data Exchange (ETDEWEB)

Darmody, R.G.; Hetzler, R.T.; Simmons, F.W. (Illinois Univ., Urbana, IL (USA). Dept. of Agronomy)

1992-01-01

Subsidence from longwall underground coal mining adversely impacts agricultural land by creating wet or ponded areas. While most subsided areas show little impact, some localized places, usually less than 1.5 ha in size, may experience total crop failure. Coal companies mitigate subsidence damaged cropland by installing drainage waterways or by adding fill material to raise the grade. The objective of this study was to test the effectiveness of mitigation in restoring corn and soybean yields to pre-mined levels. Fourteen sites in southern Illinois were selected for study. Corn ([ital Zea mays] L.) and soybean ([ital Glycine max] L.) yields from mitigated and nearby undisturbed areas were compared for four years. Results varied due to differing weather and site conditions. Mean corn yields overall, however were significantly ([alpha]0.05) lower on mitigated areas. There was no significant difference in overall mean soybean yields. Soil fertility levels were similar and did not account for yield differences. 14 refs., 1 fig., 7 tabs.

Technological possibilities for increasing coarse coal yield in the Staszic mine

Energy Technology Data Exchange (ETDEWEB)

Sikora, W; Major, M

1985-06-01

Experiments carried out in the Staszic underground black coal mine in Upper Silesia showed that there is a correlation of coarse coal yield and yield strength of shield supports used at longwall faces. The faces were equipped with Pioma 25-45, Fazos 15-31 and Fazos 19-32 shield supports, KWB 3RDU shearer loaders and Rybnik chain conveyors. Pressure of oil in water emulsion used in the Pioma 25/45 shield supports was reduced from the recommended 30 MPa to 15 MPa or to 10 MPa. Reducing emulsion pressure (and support yield strength) caused an increase in coarse coal yield. Coarse coal yield was also increased by use of Fazos 19/32 shield supports with reduced yield strength. During the tests coarse coal yield increased 1.68% and 2.65%. Test results are shown in 3 diagrams. Investigations carried out in the Staszic mine in 1983 showed that by optimizing yield strength of shield supports coarse coal yield could be increased 2 to 8%. 6 references.

A Remote Sensing Approach to Environmental Monitoring in a Reclaimed Mine Area

Directory of Open Access Journals (Sweden)

Rajchandar Padmanaban

2017-12-01

Full Text Available Mining for resources extraction may lead to geological and associated environmental changes due to ground movements, collision with mining cavities, and deformation of aquifers. Geological changes may continue in a reclaimed mine area, and the deformed aquifers may entail a breakdown of substrates and an increase in ground water tables, which may cause surface area inundation. Consequently, a reclaimed mine area may experience surface area collapse, i.e., subsidence, and degradation of vegetation productivity. Thus, monitoring short-term landscape dynamics in a reclaimed mine area may provide important information on the long-term geological and environmental impacts of mining activities. We studied landscape dynamics in Kirchheller Heide, Germany, which experienced extensive soil movement due to longwall mining without stowing, using Landsat imageries between 2013 and 2016. A Random Forest image classification technique was applied to analyze land-use and landcover dynamics, and the growth of wetland areas was assessed using a Spectral Mixture Analysis (SMA. We also analyzed the changes in vegetation productivity using a Normalized Difference Vegetation Index (NDVI. We observed a 19.9% growth of wetland area within four years, with 87.2% growth in the coverage of two major waterbodies in the reclaimed mine area. NDVI values indicate that the productivity of 66.5% of vegetation of the Kirchheller Heide was degraded due to changes in ground water tables and surface flooding. Our results inform environmental management and mining reclamation authorities about the subsidence spots and priority mitigation areas from land surface and vegetation degradation in Kirchheller Heide.

Use of IT platform in determination of efficiency of mining machines

Science.gov (United States)

Brodny, Jarosław; Tutak, Magdalena

2018-01-01

Determination of effective use of mining devices has very significant meaning for mining enterprises. High costs of their purchase and tenancy cause that these enterprises tend to the best use of possessed technical potential. However, specifics of mining production causes that this process not always proceeds without interferences. Practical experiences show that determination of objective measure of utilization of machine in mining enterprise is not simple. In the paper a proposition for solution of this problem is presented. For this purpose an IT platform and overall efficiency model OEE were used. This model enables to evaluate the machine in a range of its availability performance and quality of product, and constitutes a quantitative tool of TPM strategy. Adapted to the specificity of mining branch the OEE model together with acquired data from industrial automatic system enabled to determine the partial indicators and overall efficiency of tested machines. Studies were performed for a set of machines directly use in coal exploitation process. They were: longwall-shearer and armoured face conveyor, and beam stage loader. Obtained results clearly indicate that degree of use of machines by mining enterprises are unsatisfactory. Use of IT platforms will significantly facilitate the process of registration, archiving and analytical processing of the acquired data. In the paper there is presented methodology of determination of partial indices and total OEE together with a practical example of its application for investigated machines set. Also IT platform was characterized for its construction, function and application.

The Mine Safety and Health Administration's criterion threshold value policy increases miners' risk of pneumoconiosis.

Science.gov (United States)

Weeks, James L

2006-06-01

The Mine Safety and Health Administration (MSHA) proposes to issue citations for non-compliance with the exposure limit for respirable coal mine dust when measured exposure exceeds the exposure limit with a "high degree of confidence." This criterion threshold value (CTV) is derived from the sampling and analytical error of the measurement method. This policy is based on a combination of statistical and legal reasoning: the one-tailed 95% confidence limit of the sampling method, the apparent principle of due process and a standard of proof analogous to "beyond a reasonable doubt." This policy raises the effective exposure limit, it is contrary to the precautionary principle, it is not a fair sharing of the burden of uncertainty, and it employs an inappropriate standard of proof. Its own advisory committee and NIOSH have advised against this policy. For longwall mining sections, it results in a failure to issue citations for approximately 36% of the measured values that exceed the statutory exposure limit. Citations for non-compliance with the respirable dust standard should be issued for any measure exposure that exceeds the exposure limit.

Field investigation into the influene of anhydrite packing on longwall gate road stability

Energy Technology Data Exchange (ETDEWEB)

Dudley, W R

1977-01-01

Strata movements around a number of longwall roadways at Easington Colliery (UK), together with pack load, convergence, and area losses were determined. The influence of relatively incompressible anhydrite packs on roadway stability was particularly studied. Closures between roadways using this type of pack were compared with those using dirt filled wood chocks. The effectiveness of a Webster packer in controlling roadway convergence was assessed at Horden Colliery. The physical properties of anhydrite/accelerator mixtures likely to influence their use as a roadside packing material was also investigated. (91 refs.)

Principles of safe mechanization of operations in seams with hazards of rock and gas outbursts

Energy Technology Data Exchange (ETDEWEB)

Kozlowski, B; Siarkiewicz, R

1976-10-01

Rock burst hazards in Lower Silesia, Poland, and methods for rock burst forecasting are discussed. From 1894 to 1974, 1403 rock bursts occurred in the basin; five were accompanied by emission of methane, the rest with emission of carbon dioxide. Use of the GMA-030 sensor system (type GfG) for detecting increasing emission of carbon dioxide at longwall faces mined by coal plows is analyzed. Site selection for sensors at longwall faces (retreat or advance) in mines with ascending or descending ventilation, with blowing or exhaust ventilation systems and in mine drivage is analyzed. Examples of sensor installation at face ends are evaluated. Recommendations for sensor installation are made. 2 references.

77 FR 24673 - Grand Mesa, Uncompahgre and Gunnison National Forests; Colorado; Federal Coal Lease Modifications...

Science.gov (United States)

2012-04-25

..., topography, hydrogeology, and hydrology identified in the baseline assessment to mining activities in the... coal estate managed by the BLM. The proposed action deals primarily with underground mining. It is assumed that longwall mining practices would be used. Surface disturbance may include soil subsidence due...

Designing for success

Energy Technology Data Exchange (ETDEWEB)

Altounyan, P.; Hurt, K.; Bigby, D. [Rock Mechanics Technology, Stanhope Bretby (United Kingdom)

1999-07-01

Successful underground coal mining is dependent on a number of key factors, particularly geotechnical suitability. The impact of rock mechanics on underground mine design and mining methods is discussed in this article. Methods on minimising stress effects in room and pillar mining, and longwall mining are outlined. The use of computer numerical modelling in mine design is mentioned. 8 figs.

Renovation of production management in Kushiro Colliery

International Nuclear Information System (INIS)

Ito, Kazuyuki

1991-01-01

Kushiro Colliery operates with underground mining as one of the largest coal production in Japan, and supplies to power stations with about 25 % demand of domestic steaming coal. The colliery produces about 80 % raw coal by mechanized longwall mining introduced from 1967 which is composed of Drum Shearer, Shield Supports. A.F.C and Stage Loader. The large scale production by longwall mining brought into various problems on the safety and productivity such as lower coal recovery ratio, deeper coal fields, and the rise of mining cost. Kushiro Colliery have been developed new mining techniques accepted hard-ware and soft ware to improve the coal recovery ratio and to suppress the deeper coal fields. At present, the colliery is strongly performing higher efficiency and safety of mine management by means of the reformation of working systems, the early construction of main roadways for new coal field and intensive transportations, and the completion of safety education. Realization of various mining techniques have been pulled through the reduction of mining cost and managing innovation on the serious colliery management. (author)

30 CFR 75.823 - Scope.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Scope. 75.823 Section 75.823 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Underground High-Voltage Distribution High-Voltage Longwalls § 75.823 Scope...

Maximal loads acting on legs of powered roof support unit in longwalls with bumping hazards

Institute of Scientific and Technical Information of China (English)

StanislawSzweda

2001-01-01

during blasting. The majority of recorded force changes in the legs has been caused by a dynamic interaction of the roof. They are characterized by a load increase coefficient Kd, satisfying the inequality i .06 < Kd = Fm/Fst.p < 1.24. A much smeller number of cases, when the external load acted on the bases, was recorded. Individual, recorded results of measurements indicate that changes of the force in the legs, caused by external loads of this type, run more intensively due to roof loads (1.08 < Kd< l. 80), particularly in these cases when the nearthe-roof layer of the seam Is under mining. A determination of more precise relations among the changes of forces in the legs, caused by a dynamic interaction of the floor and the bases and the mining and geological conditions requires a performance of additional underground tests. Keywords longwall, bumping hazard, powered roof support unit

The forecast of mining-induced seismicity and the consequent risk of damage to the excavation in the area of seismic event

Directory of Open Access Journals (Sweden)

Jan Drzewiecki

2017-01-01

Full Text Available The Central Mining Institute has developed a method for forecasting the amount of seismic energy created by tremors induced by mining operations. The results of geophysical measurements of S wave velocity anomalies in a rock mass or the results of analytic calculations of the values of pressure on the horizon of the elastic layers are used in the process of calculating the energy. The calculation program which has been developed and adopted has been modified over recent years and it now enables not only the prediction of the energy of dynamic phenomena induced by mining but also the forecasting of the devastating range of seismic shock. The results obtained from this calculation, usually presented in a more readable graphic form, are useful for the macroscopic evaluation of locations that are potential sources of seismic energy. Forecasting of the maximum energy of seismic shock without prior knowledge of the location of the shock's source, does not allow shock attenuation that results from, for example, a distance of tremor source from the excavation which will be affected by seismic energy, to be taken into consideration. The phenomena of energy dissipation, which is taken into account in the forecasts, create a new quality of assessment of threat to the excavation. The paper presents the principle of a method of forecasting the seismic energy of a shock and the risk of damage to the excavation as a result of the impact of its energy wave. The solution assumes that the source of the energy shock is a resilient layer in which the sum of the gravitational stresses, resulting from natural disturbances and those induced by the conducted or planned mining exploitation, is estimated. The proposed solution assumes a spherical model for the tremor source, for which seismic energy is forecasted as a function of the longwall advance and the elementary value of seismic energy destroying the excavation. Subsequently, the following are calculated for the

Mining the 510 coal seam prone to rock bursts and below a coal support pillar in a seam above

Energy Technology Data Exchange (ETDEWEB)

Major, M; Gebala, W

1983-10-01

The 510 coal seam, situated at a depth of 760 m below a support pillar left in an overlying coal seam, was mined by a system of longwall faces from 1979 to 1982. The seam was prone to rock bursts. Energy of rock bursts which occurred in the mine ranged from 10/SUP/5 to 10/SUP/6 J. The coal seam, 10 m thick, was mined by slicing. Faces were 140 m long. Stress concentrations caused by the suppport pillar left in the overlying coal seam were calculated. Curves which describe stress fluctuations were plotted. Rock burst hazards were determined by drilling. Drilling intervals depended on hazard degree and position of the test site in relation to the support pillar in the overlying coal seam. The face was 3 m high. Supports used in 2 gate roads were reinforced by steel and timber supports. Strong timber boards were placed at canopies of powered supports used at the working face. The face was situated at an angle of 10 degrees to the pillar axis. In the zone of critical stresses water infusion and shock blasting were used for rock burst prevention. These methods, plus reinforcement of the supports in gate roads and at the working face, guaranteed safe mining and prevented rock bursts. (8 refs.)

Leading experience of reaching high labor productivity in the stoping face using grader extraction

Energy Technology Data Exchange (ETDEWEB)

Chikh, M P

1982-01-01

The main factors which hold back highly productive work are high labor intensity of reinforcing the terminal sections of the longwalls, difference in the speed characteristics of the worm and longwall conveyers, jamming of the worm conveyers, holdups in transportation, etc. Consequently under the leadership of the party and trade union organizations, organizational technical measures were developed and are constantly being improved. Shift working meetings are held at which specific solutions are adopted. In order to improve load on the face, specific measures were adopted: measures are regularly developed for maintenance and repair of the stoping face equipment; a cartogram of repair-technical operations is compiled for the longwall; the velocity of the worm conveyers is brought to the velocity of the longwall conveyer, on the scraper conveyers in the conveyer galleries the edge is increased to 0.6 m; supply of electricity to the grader and conveyer in the longwall is done by individual substations; the efficiency experts of the mines have developed and introduced an improved design of belt loader at the loading point; in order to repair equipment on off days, a special group of highly skilled mechanics has been created. Introduction of these measures together will make it possible to improve coal extraction, labor productivity, labor efficiency, reduce accident rate, reveal latent reserves. Practice has indicated that the use of the grader units with mechanized timbering IMKS makes it possible to achieve high technical-economic indicators both of the work of the brigade and the mine as a whole.

RESEARCH, DEVELOPMENT, AND EXPERIMENTAL TELECOMMUNICATIONS TECHNOLOGY

Energy Technology Data Exchange (ETDEWEB)

Zvi H. Meiksin

2002-07-01

A temporary installation of Transtek's in-mine communications system in the Lake Lynn mine was used in the mine rescue training programs offered by NIOSH in April and May 2002. We developed and implemented a software program that permits point-to-point data transmission through our in-mine system. We also developed a wireless data transceiver for use in a PLC (programmed logic controller) to remotely control long-wall mining equipment.

CFD modelling of sampling locations for early detection of spontaneous combustion in long-wall gob areas.

Science.gov (United States)

Yuan, Liming; Smith, Alex C

In this study, computational fluid dynamics (CFD) modeling was conducted to optimize gas sampling locations for the early detection of spontaneous heating in longwall gob areas. Initial simulations were carried out to predict carbon monoxide (CO) concentrations at various regulators in the gob using a bleeder ventilation system. Measured CO concentration values at these regulators were then used to calibrate the CFD model. The calibrated CFD model was used to simulate CO concentrations at eight sampling locations in the gob using a bleederless ventilation system to determine the optimal sampling locations for early detection of spontaneous combustion.

The influence of the mining operation on the mine seismicity of Vorkuta coal deposit

Science.gov (United States)

Zmushko, T.; Turuntaev, S. B.; Kulikov, V. I.

2012-04-01

The mine seismicity of Vorkuta coal deposit was analyzed. Seismic network consisting of 24 seismic sensors (accelerometers) cover the area of "Komsomolskaya" and "North" mines of Vorkuta deposit. Also there is seismic station of IDG RAS with three-component seismometer near this mines for better defining energy of the seismic events. The catalogs of seismic events contain 9000 and 7000 events with maximum magnitude M=2.3 for "Komsomolskaya" and "North" mines respectively and include the period from 01.09.2008 to 01.09.2011. The b-value of the magnitude-frequency relation was -1.0 and -1.15 respectively for the mines, meanwhile b-value for the nature seismicity was -0,9. It was found, that the number of seismic events per hour during mine combine operation is higher in 2.5 times than the number of seismic events during the break in the operation. Also, the total energy of the events per hour during the operation is higher in 3-5 times than during the break. The study showed, that the number and the energy of the seismic events relate with the hours of mine combine operation. The spatial distribution of the seismic events showed, that 80% of all events and 85% of strong events (M>1.6) were located in and near the longwall under development during the mine combine operations as well asduring the breaks. The isoclines of seismic event numbers proved that the direction of motion of the boundary of seismic events extension coincides with the direction of development, the maximum number of events for any period lies within the wall under operation. The rockburst with M=2.3 occurring at the North mine at July 16, 2011 was considered. The dependences of the energy and of the number of events with different magnitudes on the time showed that the number of events with M=1 and especially M=0.5 before the rockburst decreased, which corresponds to the prognostic seismic quietness, described in the research works. The spatial distribution of the events for the 6 month before the

Advanced face support systems for use in complex mining- geological conditions. Progressivnye tekhnologicheskie skhemy krepleniya ochistnykh zaboev v slozhnykh gorno-geologicheskikh usloviyakh

Energy Technology Data Exchange (ETDEWEB)

Rudnitskii, Yu I; Kuz' menko, N I

1985-01-01

This paper reviews utilization of advanced methods of roof control and face supports in Donbass coal mines involving the application of new technology (metal slide bars, hydraulic props with increased carrying capacity, etc.). Discusses the effect of supporting longwall areas on the stability of roofs and the application of metal roof bars together with single props in an area with unstable roof rock, particularly where the conveyor belts turn, thus achieving reliable roof support at the prop-free-front faces. This replaces chemical strengthening of the rock or the use of packs. Since the modern narrow-web cutter loaders cannot, using present methods of roof support, reduce the unsupported area to less than 8-10 m/sup 2/ and with the probability of rock falls increasing proportionally to the square of the distance between bar ends and the face, it is necessary to use methods which will increase work safety in the changing mining-geological conditions. (10 refs.)

An investigation into recharge in South African underground collieries

Energy Technology Data Exchange (ETDEWEB)

Vermeulen, P.D.; Usher, B.H. [University of the Free State, Bloemfontein (South Africa). Inst. of Groundwater Studies

2006-11-15

The Mineral and Petroleum Act of 2002 states that no closure certificate may be issued to mines unless the management of potential pollution to water resources has been addressed. Continuous recharge into the abandoned collieries occurs, and it is important for collieries that close down to plan their future management strategy accordingly. Research has been initiated to determine the recharge into abandoned mines of different mining depths, methods and size. Collieries of a nature similar to these case studies can thus associate with the recharge values obtained. Water balances are of overriding importance in determining recharge and water loss. These vary from mine to mine. Overriding factors are the method of mining, depth of mining, and surface hydrology. High extraction methods (stooping and longwall) invariably disturb the overlying strata more than bord and pillar methods. A summary of the percentage influx to be expected for the various mining methods is as follows: Shallow bord and pillar: 5-10% of the rainfall; Deep bord and pillar with no subsidence: 3-4% of the rainfall; Stooping: 5-12% of the rainfall; Longwall: 6-15% of the rainfall; Rehabilitated opencast: 14-20% of the rainfall. The actual percentages depend largely on specific circumstances.

Gas Permeability Evolution Mechanism and Comprehensive Gas Drainage Technology for Thin Coal Seam Mining

Directory of Open Access Journals (Sweden)

Fangtian Wang

2017-09-01

Full Text Available A thin coal seam mined as a protective coal seam above a gas outburst coal seam plays a central role in decreasing the degree of stress placed on a protected seam, thus increasing gas permeability levels and desorption capacities to dramatically eliminate gas outburst risk for the protected seam. However, when multiple layers of coal seams are present, stress-relieved gas from adjacent coal seams can cause a gas explosion. Thus, the post-drainage of gas from fractured and de-stressed strata should be applied. Comprehensive studies of gas permeability evolution mechanisms and gas seepage rules of protected seams close to protective seams that occur during protective seam mining must be carried out. Based on the case of the LongWall (LW 23209 working face in the Hancheng coal mine, Shaanxi Province, this paper presents a seepage model developed through the FLAC3D software program (version 5.0, Itasca Consulting Group, Inc., Minneapolis, MI, USA from which gas flow characteristics can be reflected by changes in rock mass permeability. A method involving theoretical analysis and numerical simulation was used to analyze stress relief and gas permeability evolution mechanisms present during broken rock mass compaction in a goaf. This process occurs over a reasonable amount of extraction time and in appropriate locations for comprehensive gas extraction technologies. In using this comprehensive gas drainage technological tool, the safe and efficient co-extraction of thin coal seams and gas resources can be realized, thus creating a favorable environment for the safe mining of coal and gas outburst seams.

The peculiarities of structurizing enclosing rock massif while developing a coal seam

Science.gov (United States)

Kozyreva, E. N.; Shinkevich, M. V.

2017-09-01

Different concepts of the development of geo-mechanical processes during longwall mining of a seam which are fundamentally different from the conventional ones are introduced in the article. Fundamental principles of the model for structurizing enclosing rock mass while longwall mining along the strike are described. The model was developed on the bases of non-linear geomechanical laws. According to the model, rock mass in the area of mining operation is organized as rock geomechanical layers with shifting arches. And the formation period of shifting arches in disintegrated rock mass is divisible by the length of the stope. Undulate characteristic of a massif as a peculiarity of man-made structurization of a massif is defined. It is shown that structuring the broken massif causes the formation of block-structured system and it can be detected while monitoring the ground pressure in powered support props. The results of the research allow decreasing the negative influence of a ground pressure and can be applied to specify parameters for controlling the roof, defining geometrical dimensions of a mining section and positioning of holing chute (face entry).

Application of EMD-Based SVD and SVM to Coal-Gangue Interface Detection

Directory of Open Access Journals (Sweden)

Wei Liu

2014-01-01

Full Text Available Coal-gangue interface detection during top-coal caving mining is a challenging problem. This paper proposes a new vibration signal analysis approach to detecting the coal-gangue interface based on singular value decomposition (SVD techniques and support vector machines (SVMs. Due to the nonstationary characteristics in vibration signals of the tail boom support of the longwall mining machine in this complicated environment, the empirical mode decomposition (EMD is used to decompose the raw vibration signals into a number of intrinsic mode functions (IMFs by which the initial feature vector matrices can be formed automatically. By applying the SVD algorithm to the initial feature vector matrices, the singular values of matrices can be obtained and used as the input feature vectors of SVMs classifier. The analysis results of vibration signals from the tail boom support of a longwall mining machine show that the method based on EMD, SVD, and SVM is effective for coal-gangue interface detection even when the number of samples is small.

The largest US coal acquisition takes shape

International Nuclear Information System (INIS)

Carter, R.A.

1998-01-01

The midyear purchase of Arco's US coal properties for 1.14 billion dollars gave Arch coal, Inc. (ACI) a string of surface and underground mines stretching from Wyoming's Powder River Basin to the coalfields of central Utah. The transaction created a new entity, Arch Western Resources LLC. The article describes operations at Black Thunder and Coal Creek surface mines and SUFCO, Skyline, Dugout Canyon and West Elk longwall mines. 4 photos

76 FR 37838 - Petitions for Modification of Application of Existing Mandatory Safety Standards

Science.gov (United States)

2011-06-28

... point at least 50 feet above the seam being mined, the petitioner will fracture at least six places at... roof, rib and floor to within 20 feet of the face when mining through the well. On longwall sections, rock dusting will be conducted and placed on the roof, rib, and floor up to the headgate and the...

Geomechanics of subsidence above single and multi-seam coal mining

Directory of Open Access Journals (Sweden)

A.M. Suchowerska Iwanec

2016-06-01

Full Text Available Accurate prediction of surface subsidence due to the extraction of underground coal seams is a significant challenge in geotechnical engineering. This task is further compounded by the growing trend for coal to be extracted from seams either above or below previously extracted coal seams, a practice known as multi-seam mining. In order to accurately predict the subsidence above single and multi-seam longwall panels using numerical methods, constitutive laws need to appropriately represent the mechanical behaviour of coal measure strata. The choice of the most appropriate model is not always straightforward. This paper compares predictions of surface subsidence obtained using the finite element method, considering a range of well-known constitutive models. The results show that more sophisticated and numerically taxing constitutive laws do not necessarily lead to more accurate predictions of subsidence when compared to field measurements. The advantages and limitations of using each particular constitutive law are discussed. A comparison of the numerical predictions and field measurements of surface subsidence is also provided.

Making the cut

Energy Technology Data Exchange (ETDEWEB)

Mcshannon, G. [Hydra Mining Tools International Ltd. (United Kingdom)

2006-04-15

The paper explains how coal mines around the world can benefit from the use of cowless, radial shearer drums. Hydra Mining has designed and manufactured a range of shearer drums to combat problems ranging from dust, frictional ignitions, geological problems or low production rates. This allows the mine operator to maximise production efficiency. The company tailor-makes shearer drums for each longwall face to optimise the cutting performance of every installation. 8 figs.

The Alabama, U.S.A., seismic event and strata collapse of May 7, 1986

Science.gov (United States)

Long, L.T.; Copeland, C.W.

1989-01-01

On May 7, 1986, the residents of Tuscaloosa, Alabama, felt a seismic event of local magnitude 3.6 that occurred at the same time as a rock burst and roof collapse in an active longwall coal mine. Visual inspection of the seismograms reveals a deficiency in energy at frequencies above 20 Hz compared to tectonic earthquakes or surface blasts. The predominance of energy below 5 Hz may explain reports of body wave magnitudes (mb) greater than 4.2. Also, 1.0 Hz surface waves were more strongly excited than body waves and may explain local felt effects more typically associated with greater epicentral distances. All recorded first motions were dilatational. The concentration of stations in the northern hemisphere allows reverse motion on an east-trending near-vertical plane or strike-slip motion on northwest or southeast trending planes. The reverse focal mechanism is preferred, because the area of roof collapse and the area of active longwall mining are located between two east-striking loose vertical fracture zones. The characteristics of the seismic event suggest that it might have been sudden shear failure resulting from accumulated strain energy in overlying strata behind an active longwall. Although an alternate interpretation of the focal mechanism as an implosion or shear failure in the strata above previously mined out areas is also allowed by the first motion data, this alternate intepretation is not supported by geological data. ?? 1989 Birkha??user Verlag.

Analysis of the Harmfulness of Water-Inrush from Coal Seam Floor Based on Seepage Instability Theory

Institute of Scientific and Technical Information of China (English)

无

2007-01-01

A theory of seepage instability was used to estimate the harmfulness of water-inrush from a coal seam floor in a particular coal mine of the Mining Group, Xuzhou.Based on the stratum column chart in this coal mine, the distribution of stress in mining floors when the long-wall mining was respectively pushed along to 100 m and to 150 m was simulated by using the numerical software (RFPA2D).The permeability parameters of the coal seam floor are described given the relationship between permeability parameters.Strain and the water-inrush-indices were calculated.The water-inrush-index was 67.2% when the working face was pushed to 100 m, showing that water-inrush is possible and it was 1630% when the working face was pushed to 150 m, showing that water-inrush is quite probable.The results show that as long-wall mining is pushed along, the failure zone is enlarged, the strain increased, and fissures developed correspondingly, resulting in the formation of water-inrush channels.Accompanied by the failure of the strata, the permeability increased exponentially.In contrast, the non-Darcy flow β factor and the acceleration coefficient decreased exponentially, while the increase in the water-inrush-index was nearly exponential and the harmfulness of water-inrush in the coal mine increased accordingly.

A new method to calculate permeability of gob for air leakage calculations and for improvements in methane control

Energy Technology Data Exchange (ETDEWEB)

Karacan, C.O. [National Inst. for Occupational Safety and Health, Pittsburgh, PA (United States). Office of Mine Safety and Health Research

2010-07-01

Although longwall underground mining can maximize coal production, it causes large scale disturbances of the surrounding rock mass due to fracturing and caving of the mine roof as the mine face advances. The porosity and permeability of the longwall gob can affect the methane and air flow patterns considerably. Since methane is a major hazard in underground coal mining operations, extensive methane control techniques are used to supplement the existing mine ventilation system, such as gob gas ventholes (GGV). However, the gob is rarely accessible for performing direct measurements of porosity and permeability. Therefore, this study presented a fractal approach for calculating the porosity and permeability from the size distribution of broken rock material in the gob, which can be determined from image analyses. The fractal approach constructs flow equations and fractal crushing equations for granular materials to predict porosity for a completely fragmented porous medium. The virtual fragmented fractal porous medium is exposed to various uniaxial stresses to simulate gob compaction and porosity and permeability changes during this process. It was concluded that the use of this fractal approach will result in better predictions regarding the flow amount and flow patterns in the gob, and facilitate leakage calculations and methane control projections. 29 refs., 4 tabs., 5 figs.

Causes of falls of hangingwall over gullies adjacent to stabilizing strike pillars

CSIR Research Space (South Africa)

Turner, PA

1987-08-01

Full Text Available This report discusses the occurrence of falls of ground in strike gullies. Falls of hangingwall over strike gullies on the up-dip side of strike stabilizing pillars in longwall mining systems were investigated. Gullies were examined in both...

Selection of powered roof support for weak coal roof

Energy Technology Data Exchange (ETDEWEB)

Ramayya, M.S.V.; Sudhakar, L. [Singareni Collieries Co. Ltd., Kothagudem (India)

2002-04-01

Singareni Collieries Company Ltd (SCCL) introduced mechanised longwall mining in 1983. The first few faces were worked with conventional and immediate forward supports (IFS), with capacities in the range of 360 to 450 t. These under capacity supports increased from abutment loads and there was breakage of roof in front of the supports which resulted in closure of powered roof supports, followed by face cavities. The cavities were more frequent and were difficult to negotiate especially in case of IFS supports. Subsequently, support capacity was increased at Padmavati Khani (PVK) mine and at GDK.10a and GKD.9LFP Inclines where the roof is composed of weak, coal, shale and clay. Problems related to failure of hydraulics/legs etc., which are repairable have occurred; though the problems are not totally eliminated, there was definite improvement in strata control with these higher capacity supports. Monitoring of supports was conducted all through the working of longwall panels. The data generated while working these longwall faces were analysed to study the suitability of other types of powered roof supports, namely 2 legged shield supports/4 legged supports for improved strata control. The analysis and practical experiences suggest that in weak, coaly, shale and clay roofs 2 legged shield supports offer better roof control. 4 refs., 4 figs.

Improvements in seismic event locations in a deep western U.S. coal mine using tomographic velocity models and an evolutionary search algorithm

Energy Technology Data Exchange (ETDEWEB)

Adam Lurka; Peter Swanson [Central Mining Institute, Katowice (Poland)

2009-09-15

Methods of improving seismic event locations were investigated as part of a research study aimed at reducing ground control safety hazards. Seismic event waveforms collected with a 23-station three-dimensional sensor array during longwall coal mining provide the data set used in the analyses. A spatially variable seismic velocity model is constructed using seismic event sources in a passive tomographic method. The resulting three-dimensional velocity model is used to relocate seismic event positions. An evolutionary optimization algorithm is implemented and used in both the velocity model development and in seeking improved event location solutions. Results obtained using the different velocity models are compared. The combination of the tomographic velocity model development and evolutionary search algorithm provides improvement to the event locations. 13 refs., 5 figs., 4 tabs.

A new approach to predict underground gassiness for design of gas capture and ventilation systems

Energy Technology Data Exchange (ETDEWEB)

Lunarzewski, L.W.; Lunarzewski, A.L. [Lunagas Pty Limited, Junction (Australia); Pilcher, R.C. [Raven Ridge Resources, Grand Junction, CO (United States)

1995-12-31

The Floorgas and Roofgas simulation programs are used to identify strata relaxation zones and their boundaries, to assess active gas sources from coal seams and gas-bearing rocks and to determine relevant gassiness prediction coefficients for any local longwall. The paper shows that by use of the print-outs from the Floorgas and Roofgas programs the following benefits are achievable: (1) identification of the shear and gas discharge zone positions in the floor, strata relaxation angles and various gas discharge zone positions in the roof, which are both relevant to local geological and mining conditions; (2) optimisation of cross-measure drainage hole length, location, number and angle of inclination; and (3) calculation and definition of gas make prediction coefficients such as the release ratio from adjacent coal seams, specific gas emission during longwall extraction and the relationships between gas make, longwall width and coal production levels.

Case Studies of Rock Bursts Under Complicated Geological Conditions During Multi-seam Mining at a Depth of 800 m

Science.gov (United States)

Zhao, Tong-bin; Guo, Wei-yao; Tan, Yun-liang; Yin, Yan-chun; Cai, Lai-sheng; Pan, Jun-feng

2018-05-01

A serious rock burst ("4.19" event) occurred on 19 April 2016 in the No. 4 working face of the No. 10 coal seam in Da'anshan Coal Mine, Jingxi Coalfield. According to the China National Seismological Network, a 2.7 magnitude earthquake was simultaneously recorded in this area. The "4.19" event resulted in damage to the entire longwall face and two gateways that were 105 m in long. In addition, several precursor bursts and mine earthquakes had occurred between October 2014 and April 2016 in the two uphill roadways and the No. 4 working face. In this paper, the engineering geological characteristics and in situ stress field are provided, and then the rock burst distributions are introduced. Next, the temporal and spatial characteristics, geological and mining conditions, and other related essential information are reviewed in detail. The available evidence and possible explanations for the rock burst mechanisms are also presented and discussed. Based on the description and analysis of these bursts, a detailed classification system of rock burst mechanisms is established. According to the main causes and different disturbance stresses (i.e., high/low disturbance stresses and far-field/near-field high disturbance stresses), there are a total of nine types of rock bursts. Thus, some guidelines for controlling or mitigating different types of rock bursts are provided. These experiences and strategies not only provide an essential reference for understanding the different rock burst mechanisms, but also build a critical foundation for selecting mitigation measures and optimizing the related technical parameters during mining or tunnelling under similar conditions.

Engineer exchanging project on coal mine technology field in fiscal 1999. International information exchanging project (advance survey on North America); 1999 nendo gijutsusha koryu jigyo (tanko gijutsu bun'ya) kokusai koryu jigyo. Jizen chosa (Hokubei)

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

This project has been performed with an intention of making visiting surveys and information collection at coal related organizations in overseas coal producing countries on production technology levels and trends. The project is intended to serve for improvement in the contents of and smooth execution of the engineer exchange project in the 'coal mine technology field. It was carried out by the site surveys. The surveys revealed that the situation of the American coal industry is expected of stable increase in the demand and supply in the future, but the coal price is on the falling trend, and therefore, the industry is compelled to further increase the intensity and enhance the productivity. The industry is strongly influenced by the amended air pollution prevention act and nature destruction problems, hence further coal mine curtailment is estimated. Under such a background, it was found that the long-wall mining process progressing toward larger scale and higher productivity, and the high-wall mining process that provides higher productivity at lower cost and has less impact on the environmental problems can continue development in mountainous areas, particularly in the Appalachian area. The high-wall mining process mines coal at exposed facings on the side of a mountain by using a continuous miner, and transports the coal using machines. (NEDO)

Fiscal 1999 report on basic research for promotion of joint implementation programs. Research on collection and utilization of coal mine methane gas in Russia (Kuznetsk coal field); Russia (Kuznetsk tanden) ni okeru tanko methane gas kaishu riyo chosa hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-03-01

The above-mentioned effort is to comply with the COP3 (Third Session of the Conference of the Parties to the United Nations Framework Convention on Climate Change) joint implementation clause. At this coal field, mining facilities are growing superannuated and obsolescent in the prolonged business depression, causing frequent occurrence of disasters such as gas explosions. The coal mine gas collection rate at the Kuznetsk coal field is as low as 17%, with concern for safety discouraging sufficient collection. Even the small amount of the collected gas is, in the absence of gas utilizing facilities, totally discharged into the air. For the mitigation of global warming, for mining safety, and for the establishment of a foundation for business, it is desired that coal mine methane gas collection/utilization facilities and related technologies be introduced into the coal field. Gas purging from the pits is incomplete, which is attributed to the lack of equipment capable of excavating proper-diameter bores longer than 100m for longwall mining. Ventilation also needs improvement. The research is under way on the premise that highly reliable intermediate range (300m) boring equipment and gas management technologies will be available. Collection of gas of a 30-35% concentration level at a collection rate of 40% is the target. (NEDO)

New technologies of mining stratal minerals and their computation

Science.gov (United States)

Beysembayev, K. M.; Reshetnikova, O. S.; Nokina, Z. N.; Teliman, I. V.; Asmagambet, D. K.

2018-03-01

The paper considers the systems of flat and volumetric modeling of controlling long-wall faces for schemes with rock collapse of the immediate and main roof and smooth lowering of the remaining layers, as well as in forming a vault over the face. Stress distributions are obtained for the reference pressure zone. They are needed for recognizing the active state of the long-wall face in the feedback mode. The project of the system “support - lateral rocks” is represented by a multidimensional network base. Its connections reflect the elements of the system or rocks, workings, supports with nodes and parts. The connections reflect the logic of the operation of machines, assemblies and parts, and the types of their mechanical connections. At the nodes of the base, there are built-in systems of object-oriented programming languages. This allows combining spatial elements of the system into a simple neural network.

Stability Control of Retained Goaf-Side Gateroad under Different Roof Conditions in Deep Underground Y Type Longwall Mining

Directory of Open Access Journals (Sweden)

Zhiyi Zhang

2017-09-01

Full Text Available Stability of the retained goaf-side gateroad (RGSG is influenced mainly by the movements of the roof strata near coal seam after coalface passes by. To make effective controlling technology for the stability of the RGSG, we analyze the roof structure over the RGSG to illustrate the mechanism causing the RGSG instability under different roof conditions. We then examine the dynamic evolution of the deformation and abutment stress in the rock surrounding the RGSG during coal seam mining, using the FLAC3D numerical software to reveal the instability characteristics of the RGSG under different roof conditions. Next, corresponding stability controlling technologies for the RGSGs are proposed and tested in three typical deep underground coalmines. Results show that: sink and rotation of the roof cantilever over the RGSG impose severer influence on the stability of the RGSG. The RGSG suffers disturbances three times during the coal-seam mining, and the deformation and abutment stress in the rock surrounding the RGSG increase significantly when the main roof becomes thicker and the immediate roof becomes thinner. Staged support technology involving grout cable bolts has better controlling results of the RGSG stability than that composed of conventional rock bolts, when the RGSG is beneath weak immediate roof with large thickness. Roof structure optimizing technology involving pre-split technology can improve the stability of the RGSG effectively when the RGSG is covered by hard main roof with large thickness directly.

Stress Distribution in a Coal Seam before and after Bump Initiation

Directory of Open Access Journals (Sweden)

J. Vacek

2001-01-01

Full Text Available This paper deals with to the behaviour of open rock that occurs, for example, during longwall mining in coal mines, in deep tunnel, or shaft excavation.Longwall instability leads to extrusion of rock mass into an open space. This effect is mostly referred to as a bump, or a rock burst. For bumps to occur, the rock has to possess certain particular rock burst properties leading to accumulation of energy and the potential to release this energy. Such materials may be brittle, or the bumps may arise at the interfacial zones of two parts of the rock, that have principally different material properties.The solution is based on experimental and mathematical modelling. These two methods have to allow the problem to be studied on the basis of three presumptions: – the solution must be time dependent – the solution must allow the creation of crack in the rock mass – the solution must allow an extrusion of rock into an open space (bump effect

Control effect of fracture on hard coal cracking in a fully mechanized longwall top coal caving face

Energy Technology Data Exchange (ETDEWEB)

Jin-ping Wei; Zhong-hua Li; Pei-miao Sang; Shang-qiang Chen [Henan Polytechnic University, Jiaozuo (China). School of Energy Science and Engineering

2009-03-15

Through theoretical analysis, simulation test and practice, the law of a fracture's influence on hard top coal press cracking was studied. The study focused on the relation between fracture and coal strength, top coal caving ability and work face layout. Based on the investigation of the fracture system, the control of press cracking was achieved by matching working face to fracture orientation to improve top-coal caving ability and recovery. The matching principle was pointed out: the top-coal caving working face should be perpendicular to or obliquely cross the primary fracture at a large angle, and cross the secondary fracture at a small angle. The rational match can increase the recovery ratio of top-coal and avoid rib spalling. The application of control technology on hard top coal press cracking was introduced at the longwall top-coal caving face. 10 refs., 2 figs., 1 tab.

High tech conveyors unitize Selby coal

Energy Technology Data Exchange (ETDEWEB)

1985-10-01

Designs proposed by Anderson Strathclyde PLC and Cable Belt for single-flight conveyors to bring the output of the five Selby mines to the surface have both been developed by the UK National Coal Board. Both designs extend the limits of conveyor technology and are expected to economise on transport and longwalling costs. 4 references.

New means of communication for working faces

Energy Technology Data Exchange (ETDEWEB)

Brzozka, E.; Kaluzny, M.; Paluch, A.

1987-11-01

Discusses development of communications systems for underground coal mines in Poland and other COMECON countries. Standard communication systems e.g. the GST system for communications at longwall faces (used in Poland since 1976) are described. Two recently developed systems are comparatively evaluated: the EZT-2 system developed in Czechoslovakia and the GSTR system developed in Poland. The EZT-2 system consisting of the EZT-13 stationary equipment and 30 units of a transmitter-receivers (installed on a miner's helmet) is used for radio communications at a working face. The GSTR system developed in Poland is used for radio communications at longwall faces together with the GST, GLT or UGS systems or independently. The system consists of a variable number of transmitters situated along the face and 2 receivers situated in the gate roads. The YLY 1x4 mm/sup 2/ cable is used as an antenna. Design and operation of the GSTR system under operational conditions in a mine in Upper Silesia are evaluated. Effects of surrounding strata on radio wave attenuation are analyzed. 8 refs.

Cutting through - open entries require proper support

Energy Technology Data Exchange (ETDEWEB)

Peng, S.S. [West Virginia University, Morgantown, WV (USA). Mining Engineering Dept.

2000-06-01

The paper explains the applications of open entries in mining and different roof techniques to relieve longwall abutment pressures. The primary support for the open (or cut-through) entries and recovery rooms are normally similar to other development entries in the same mines. The supplementary supports installed can be divided into the following three types: complete backfill of open entries, supplemental roof and/or rib-bolt reinforcement only - no standing support and rows of standing support with or without supplemental roof and/or rib-bolt reinforcement. 3 figs.

The global supplier - myth or reality?

Energy Technology Data Exchange (ETDEWEB)

Crawshaw, S A.M. [Long-Airdox Ltd., Ilkeston (United Kingdom)

2002-02-01

Coal remains a key feature of the world's energy and steel markets and coal mining is a global industry. Suppliers of equipment to the coal-mining industry have seen traditional markets almost disappear and new markets emerge. Suppliers need to work closely with customers, sometimes in remote areas developing long-term partnerships and continually improving the product to their mutual benefit. An attempt to explain how global changes to the underground coal industry have influenced the supply of coal-mining equipment is illustrated by recent developments in the Long-Airdox group. An example is given of how the group worked with the Cayirhan Mine in Turkey supplying cast armoured face conveyors for longwall mining. The paper was presented at a meeting of the Nottinghamshire Branch of the Institution of Mining and Metallurgy on 3 June 1998 in Nottinghamshire, UK. 1 fig.

Degassification and methane drainage in thick and vertical coal seams worked by horizontal sublevel caving method; Drenaje y Desgasificacion de Grisu en Capas de Carbon Potentes y Verticales, Explotadas por subniveles Horizontales con sutiraje

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

The present trend of the working in spanish coal underground mines is directed towards the utilization, if the deposit characteristics permit it, of mining method by horizontal sublevels with caving. The application of this method involves an important coal volume in specific situations inside the workings cycle (shots, roof cavings, workings beginning, etc). Therefore, those considerable quantities of coal put into circulation, joined to high firedamp concentration desorbable of coal seam, produce in a instantaneous way large volumes of firedamp in the mine atmosphere with the consequent associated risk for the mine people, the stoppage of the works and its evacuation. These aforementioned risks could be avoided, or at least decreased to a great extent, through a methane capture before its circulation in openings caused by the mining works or by draining from accumulation rooms. During the last years, basically in EU countries, some researches have been accomplished about previous Degassification and methane capture in longwall faces of horizontal seams. In these researches have been studied the methane capture both from surface and from underground. In sublevel caving workings, substantially different from longwall faces workings, the techniques and capture systems utilized in the first one are not applicable to the second. The field works and measurements of this project have been mainly carried out in two mining companies located at the north of Spain, the Mina la Camocha S. A. and the S. A. Hullera Vasco Leonesa. Many methane capture tests by means of boreholes in coal seam have been carried out to determine the influence that capture boreholes exert in degassification of coal panel. Otherwise, many firedamp drainage tests in accumulation rooms have been also carried out, and a small-scale system that makes possible the capture in safe conditions have been defined and tested. (Author)

Landslides in the area of the Jastrzebie town protective pillar

Energy Technology Data Exchange (ETDEWEB)

Rybicki, S

1986-01-01

Analyzes 76 landslides in the area of the safety pillar of Jastrzebie in the Rybnik coal region. Of 76 landslides 60% fell on natural slopes with an angle of 25-50 degrees, 22% on natural slopes with a 5-25 degree angle, 10% on man-made cuts and 8% on embankments. About 78% of the landslides was associated with water bearing layers. Of the 76 landslides 32 were situated in the safety pillar and 44 close to the pillar. Thirty-three landslides were closely associated with underground mining: 30 landslides were caused by longwall mining (landslide position was related to working face position), a further 3 were associated with mining in general. Statistical data on landslides associated with underground coal mining are analyzed: landslide area, angle of slope inclination, height, landslide range, water conditions, types of soils, types of mining areas classified according to effects of mining damage. 8 refs.

Estimating of aquifer parameters from the single-well water-level measurements in response to advancing longwall mine by using particle swarm optimization

Science.gov (United States)

Buyuk, Ersin; Karaman, Abdullah

2017-04-01

We estimated transmissivity and storage coefficient values from the single well water-level measurements positioned ahead of the mining face by using particle swarm optimization (PSO) technique. The water-level response to the advancing mining face contains an semi-analytical function that is not suitable for conventional inversion shemes because the partial derivative is difficult to calculate . Morever, the logaritmic behaviour of the model create difficulty for obtaining an initial model that may lead to a stable convergence. The PSO appears to obtain a reliable solution that produce a reasonable fit between water-level data and model function response. Optimization methods have been used to find optimum conditions consisting either minimum or maximum of a given objective function with regard to some criteria. Unlike PSO, traditional non-linear optimization methods have been used for many hydrogeologic and geophysical engineering problems. These methods indicate some difficulties such as dependencies to initial model, evolution of the partial derivatives that is required while linearizing the model and trapping at local optimum. Recently, Particle swarm optimization (PSO) became the focus of modern global optimization method that is inspired from the social behaviour of birds of swarms, and appears to be a reliable and powerful algorithms for complex engineering applications. PSO that is not dependent on an initial model, and non-derivative stochastic process appears to be capable of searching all possible solutions in the model space either around local or global optimum points.

Barriers to the future

Energy Technology Data Exchange (ETDEWEB)

Massey, C T

1986-09-01

Opportunities for the British coal industry seem vast yet there are still barriers to progress. Seven areas are identified and discussed: mining mobility (for example, longwall mining systems are rigid and inflexible compared with American stall and pillar working); mine structure (many mines are more suitable to pit ponies than to large pieces of equipment); financial barriers (Government requires the industry to break even in 1987/88); personnel barriers (less specialization, better use of skills); safety barriers (increased use of remote control, ergonomics and robotics to protect workers); microelectronic management (nationalization has cushioned management from the market place; there is a need for a more multidisciplinary approach to the industry); and legal barriers (most legislation in the past has been in response to accidents; legislation external to the industry but affecting it is more fundamental).

Mine drivage in hydraulic mines

Energy Technology Data Exchange (ETDEWEB)

Ehkber, B Ya

1983-09-01

From 20 to 25% of labor cost in hydraulic coal mines falls on mine drivage. Range of mine drivage is high due to the large number of shortwalls mined by hydraulic monitors. Reducing mining cost in hydraulic mines depends on lowering drivage cost by use of new drivage systems or by increasing efficiency of drivage systems used at present. The following drivage methods used in hydraulic mines are compared: heading machines with hydraulic haulage of cut rocks and coal, hydraulic monitors with hydraulic haulage, drilling and blasting with hydraulic haulage of blasted rocks. Mining and geologic conditions which influence selection of the optimum mine drivage system are analyzed. Standardized cross sections of mine roadways driven by the 3 methods are shown in schemes. Support systems used in mine roadways are compared: timber supports, roof bolts, roof bolts with steel elements, and roadways driven in rocks without a support system. Heading machines (K-56MG, GPKG, 4PU, PK-3M) and hydraulic monitors (GMDTs-3M, 12GD-2) used for mine drivage are described. Data on mine drivage in hydraulic coal mines in the Kuzbass are discussed. From 40 to 46% of roadways are driven by heading machines with hydraulic haulage and from 12 to 15% by hydraulic monitors with hydraulic haulage.

COALVAL

International Nuclear Information System (INIS)

Plis, M.N.; Rohrbacher, T.J.; Teeters, D.D.

1992-01-01

This paper highlights COALVAL, a coal property evaluation software package developed by the U.S. Bureau of Mines (USBM) on Lotus 1-2-3, version 2.2, spreadsheet. The software is also compatible with version 3.1, and provisionally with version 2.01. COALVAL is a menu-driven program that produces a prefeasibility-level cost analysis of mine-planned coal resources. The software contains cost models for each of five coal mining methods commonly employed in Appalachia: auger, contour strip, mountain top removal, continuous miner and longwall. COALVAL allows individuals to input resource data and the various production, operating, and cost variables that pertain to their property The program can evaluate up to 25 seams, each to be mined with up to 5 different mining methods, within a given area. Summary spreadsheet listing the cost per clean ton to mine the resources, F.O.B. The tipple, are produced for each property, seam, and mining method/seam combination

Technical devices of powered roof support for the top coal caving as automation objects

Science.gov (United States)

Nikitenko, M. S.; Kizilov, S. A.; Nikolaev, P. I.; Kuznetsov, I. S.

2018-05-01

In the paper technical devices for the top coal caving as automation objects in the composition of the longwall mining complex (LTCC) are considered. The proposed concept for automation of the top coal caving process allows caving efficiency to be ensured, coal dilution to be prevented, conveyor overloading to be prevented, the shearer service personnel to be unloaded, the influence of the “human factor” to be reduced.

30 CFR 18.53 - High-voltage longwall mining systems.

Science.gov (United States)

2010-07-01

...-starter enclosure, with the exception of a controller on a high-voltage shearer, the disconnect device...) shielding between the primary and secondary windings. The shielding must be connected to equipment ground by... with a disconnect device installed to deenergize all high-voltage power conductors extending from the...

Application of Spaceborne Differential Radar Interferometry to Rockbursts, Mining Subsidence and Shallow Moderate Earthquakes

Science.gov (United States)

Eneva, M.; Baker, E.

2002-12-01

We have processed ERS SAR scenes for several sites of rockbursts and mining subsidence, including South Africa (gold), Colorado (coal), the state of New York (salt), Germany (potash), and Poland (copper). We are also looking at JERS-1 scenes from a potash mine in the Ural mountains (Russia) for which no suitable ERS data exist. Sizeable mining-induced events have occurred at most of these sites: mb5.1 in April 1999, S. Africa; ML3.6 in March 1994, New York; ML4.8 in September 1996, Germany; mb4.9 in April 2000, Poland; and mb4.7 in January 1995, Urals. It is reasonable to expect detectable surface displacements from rockbursts, as they are rather shallow compared with tectonic earthquakes of similar size. Indeed, in the case of the 1999 S. African event differential InSAR detects up to 9-cm displacement away from the satellite, while the 1995 collapse in the Urals has resulted in up to 4.5-m surface subsidence. Some of the study rockbursts have occurred on the background of ongoing mining subsidence (e. g., Poland, Urals, New York), adding a detectable boost to the existing subsidence rate. In other cases, mining subsidence is planned and intermittent, without unexpected collapse (e.g., long-wall coal mining in Colorado). We have applied deformation modeling using a 3D finite-difference code, focusing on the April 1999 event that was associated with a normal slip along the Dagbreek fault. Seismic events in this area (Welkom, S. Africa) are commonly associated with collapse of mined out volumes around west-dipping normal faults, but it is not clear how these faults contribute to the seismic and static displacements. The 1999 event provides an opportunity to address this ambiguity, as our InSAR measurements of surface displacements are complemented by local, regional, and teleseismic waveform records, as well as by measurements of displacements in the mine tunnels intersecting the Dagbreek fault. We are using these data to constrain the source and are investigating

Mining and mining authorities in Saarland 2016. Mining economy, mining technology, occupational safety, environmental protection, statistics, mining authority activities. Annual report

International Nuclear Information System (INIS)

2016-01-01

The annual report of the Saarland Upper Mining Authority provides an insight into the activities of mining authorities. Especially, the development of the black coal mining, safety and technology of mining as well as the correlation between mining and environment are stressed.

Comparison of coarse coal dust sampling techniques in a laboratory-simulated longwall section.

Science.gov (United States)

Patts, Justin R; Barone, Teresa L

2017-05-01

Airborne coal dust generated during mining can deposit and accumulate on mine surfaces, presenting a dust explosion hazard. When assessing dust hazard mitigation strategies for airborne dust reduction, sampling is done in high-velocity ventilation air, which is used to purge the mining face and gallery tunnel. In this environment, the sampler inlet velocity should be matched to the air stream velocity (isokinetic sampling) to prevent oversampling of coarse dust at low sampler-to-air velocity ratios. Low velocity ratios are often encountered when using low flow rate, personal sampling pumps commonly used in underground mines. In this study, with a goal of employing mine-ready equipment, a personal sampler was adapted for area sampling of coarse coal dust in high-velocity ventilation air. This was done by adapting an isokinetic nozzle to the inlet of an Institute of Occupational Medicine (Edinburgh, Scotland) sampling cassette (IOM). Collected dust masses were compared for the modified IOM isokinetic sampler (IOM-MOD), the IOM without the isokinetic nozzle, and a conventional dust sampling cassette without the cyclone on the inlet. All samplers were operated at a flow rate typical of personal sampling pumps: 2 L/min. To ensure differences between collected masses that could be attributed to sampler design and were not influenced by artifacts from dust concentration gradients, relatively uniform and repeatable dust concentrations were demonstrated in the sampling zone of the National Institute for Occupational Safety and Health experimental mine gallery. Consistent with isokinetic theory, greater differences between isokinetic and non-isokinetic sampled masses were found for larger dust volume-size distributions and higher ventilation air velocities. Since isokinetic sampling is conventionally used to determine total dust concentration, and isokinetic sampling made a difference in collected masses, the results suggest when sampling for coarse coal dust the IOM-MOD may

Subsidence monitoring program at Cyprus Coal's Colorado operations

International Nuclear Information System (INIS)

Stewart, C.L.; Shoemaker, J.E.

1992-01-01

Published subsidence data for the western United States is limited in comparison with data for the east. This paper summarizes the results of a subsidence monitoring program above two longwall panels at the Foidel Creek Mine located in northwest Colorado. The monitoring area is characterized by overburden ranging from 1000 ft to 1100 ft in thickness. the surface slope parallels the dip of the bedding at approximately 5 deg. Average mining height is 9 ft. Smax averaged 3.4 ft. Draw angles averaged 15 deg for up-dip ribsides and 19 deg for down-dip ribsides. A site-specific profile function is developed from the data

Minerals and energy: major development projects - April 2005 listing

Energy Technology Data Exchange (ETDEWEB)

Ian Haine (and others) [Australian Bureau of Agricultural and Resource Economics (ABARE), Canberra, ACT (Australia)

2005-06-01

The article describes trends in project development and investment in the minerals and energy sector in Australia. It lists competed projects and committed projects. Black coal projects completed during November 2004 to April 2005 were: Dendrobium underground and Mandalong longwall mining expansion projects in New South Wales and development of Curragh North and Eaglefield opencut mine in Queensland. One of the more significant newly listed projects is Macarthur Coal's Queensland Coke Project near Rockhampton. Capital cost and values of projects are included. The full listing of 229 projects is available electronically from ABARE. The list is released around May and November each year. 10 figs., 4 tabs.

Mine Water Treatment in Hongai Coal Mines

Science.gov (United States)

Dang, Phuong Thao; Dang, Vu Chi

2018-03-01

Acid mine drainage (AMD) is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine drainage treatment in Hongai coal mines. In addition, selection and criteria for the design of the treatment systems have been presented.

Mine Water Treatment in Hongai Coal Mines

OpenAIRE

Dang Phuong Thao; Dang Vu Chi

2018-01-01

Acid mine drainage (AMD) is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine ...

Mine Water Treatment in Hongai Coal Mines

Directory of Open Access Journals (Sweden)

Dang Phuong Thao

2018-01-01

Full Text Available Acid mine drainage (AMD is recognized as one of the most serious environmental problem associated with mining industry. Acid water, also known as acid mine drainage forms when iron sulfide minerals found in the rock of coal seams are exposed to oxidizing conditions in coal mining. Until 2009, mine drainage in Hongai coal mines was not treated, leading to harmful effects on humans, animals and aquatic ecosystem. This report has examined acid mine drainage problem and techniques for acid mine drainage treatment in Hongai coal mines. In addition, selection and criteria for the design of the treatment systems have been presented.

World wide developments in shortwall and wide web mining techniques

Energy Technology Data Exchange (ETDEWEB)

Pollard, T

1975-11-01

The paper describes the progress to date with continuous pillar extraction, and how the typical longwall powered support has been modified to be both strong enough and stable enough to provide roof support for very wide webs. It also describes the operating systems which have been specially designed. The next stages of development are discussed, particularly the provision of continuous conveyor haulage in place of the present-day shuttle car. The author suggests that marrying American coal-getting technology and British roof support technology might increase productivity.

Study of the ‘lifeline’ as the measure allowing for safe self-rescue of miners in conditions of lack of visibility caused by underground fire

Science.gov (United States)

Badura, Henryk; Grodzicka, Aneta; Musioł, Dariusz

2017-11-01

The article presents statistical data regarding the evacuation of miners affected by underground fire hazards. The data indicates that the hazard remains considerable. Due to the increasing lengths of escape routes, measures should be introduced in the longwall regions, which shall improve the safe evacuation of miners, especially in conditions of highly limited visibility or the lack thereof. Within the research project No. 12, entitled: ‘The development of orientation systems and systems for signalling the direction of crew withdrawal for escape routes in longwall gates’, which is a part of the Strategic Research Project entitled ‘The improvement of work safety in mines’ financed by the National Centre for Research and Development, a ‘lifeline’ was designed - that is, a measure that is very effective in the evacuation of staff. Subsequently, tests of time of passage were conducted in the ‘Krupiński’ coal mine in conditions of lack of visibility. The tests have confirmed the suitability of the ‘lifeline’ as the measure used for orientation towards the correct direction of evacuation, which increases the pace and the confidence while travelling through the escape route. The mean speed of passage through the heading with an upwards inclination of 11° was 22 m/min, while in case of a nearly horizontal longwall gate, it was 39 m/min.

The chosen needs of Polish restructured coal mines concerning the ventilation and struggling against gas, dust and air-conditioning dangers

Energy Technology Data Exchange (ETDEWEB)

Matuszewski, K. [Rudzka Coal Company (Poland)

2001-07-01

In this paper the selected needs of Polish coal mines with regard to their ventilation, minimisation of gas, dust and air-shortage dangers are presented. As far as ventilation is concerned: the need to broaden the use of the synchronic inverter cascades for speed regulation of main fans and the delivery of ventilation air duct to ensure a delivery of 11,117 m{sup 3}/s (6,5011,000 m{sup 3}/min) has been shown. As far as gas dangers are concerned there exists a need for the dissemination of dispatcher's help systems, training safety personnel in use of so called synoptic display table, a supply of 0,8311,67 m{sup 3}/s (501,100 m{sup 3}/min) of nitrogen in gaseous state for fire prevention as well as the use of modern mineral and chemical means have been mentioned. In order to help to reduce the dust danger the projected need for a modern generation of dry or wet dust collectors enabling a reduction in dustiness to NDS standards and equipping all longwalls with cutting machines with permanent and working installations of internal sprinklers have been postulated. In the case of air conditioning, the need to install 300 kW movable coolers with 300 kW single gear fans for the supply of 10 m{sup 3}/s (600 m{sup 3}/min) and an overall air pressure increase from 1600 to 2000 Pa has been presented. In the most dangerous coal mines attention has been drawn to the need for the installation and application of stationery coolers operating intermittently. 6 refs.

International mining forum 2004, new technologies in underground mining, safety in mines proceedings

Energy Technology Data Exchange (ETDEWEB)

Jerzy Kicki; Eugeniusz Sobczyk (eds.)

2004-01-15

The book comprises technical papers that were presented at the International Mining Forum 2004. This event aims to bring together scientists and engineers in mining, rock mechanics, and computer engineering, with a view to explore and discuss international developments in the field. Topics discussed in this book are: trends in the mining industry; new solutions and tendencies in underground mines; rock engineering problems in underground mines; utilization and exploitation of methane; prevention measures for the control of rock bursts in Polish mines; and current problems in Ukrainian coal mines.

Sustainable Mining Environment: Technical Review of Post-mining Plans

Directory of Open Access Journals (Sweden)

Restu Juniah

2017-12-01

Full Text Available The mining industry exists because humans need mining commodities to meet their daily needs such as motor vehicles, mobile phones, electronic equipment and others. Mining commodities as mentioned in Government Regulation No. 23 of 2010 on Implementation of Mineral and Coal Mining Business Activities are radioactive minerals, metal minerals, nonmetallic minerals, rocks and coal. Mineral and coal mining is conducted to obtain the mining commodities through production operations. Mining and coal mining companies have an obligation to ensure that the mining environment in particular after the post production operation or post mining continues. The survey research aims to examine technically the post-mining plan in coal mining of PT Samantaka Batubara in Indragiri Hulu Regency of Riau Province towards the sustainability of the mining environment. The results indicate that the post-mining plan of PT Samantaka Batubara has met the technical aspects required in post mining planning for a sustainable mining environment. Postponement of post-mining land of PT Samantaka Batubara for garden and forest zone. The results of this study are expected to be useful and can be used by stakeholders, academics, researchers, practitioners and associations of mining, and the environment.

Contract Mining versus Owner Mining

African Journals Online (AJOL)

Owner

mining companies can concentrate on their core businesses while using specialists for ... 2 Definition of Contract and Owner. Mining ... equipment maintenance, scheduling and budgeting ..... No. Region. Amount Spent on. Contract Mining. ($ billion). Percent of. Total. 1 ... cost and productivity data based on a large range.

Optimization of mining design of Hongwei uranium mine

International Nuclear Information System (INIS)

Wu Sanmao; Yuan Baixiang

2012-01-01

Combined with the mining conditions of Hongwei uranium mine, optimization schemes for hoisting cage, mine drainge,ore transport, mine wastewater treatment, power-supply system,etc are put forward in the mining design of the mine. Optimized effects are analyzed from the aspects of technique, economy, and energy saving and reducing emissions. (authors)

Perspectives of roof bolt use in the Kuzbass

Energy Technology Data Exchange (ETDEWEB)

Shirokov, A P

1983-10-01

Use of roof bolting for strata control in mine roadways and underground chambers in Kuzbass mines is discussed. Use of roof bolting in the Kuzbass is increasing. In 1982 roof bolting was used in 50% of workings driven in the basin; in 15 coal mines roof bolting was the predominant method for strata control. Use of roof bolting rather than timber props permitted advance rate of mine drivage in the Kuzbass to be increased by 1.5-2.0 times. Interaction between roof bolts and rock strata is analyzed. The following bolt types are considered: timber roof bolts, steel expansion shell bolts and thread bar bolts. Bolt design is shown, along with methods for roof bolt installation in roadways and chambers. Roof bolting during level, inclined or steep seam mining, for strata control at junctions of working faces with gate roads, at junctions of 2 roadways, in coal chutes, in hydraulic mines, during thick seam slicing with hardening stowing and longwall mining with hydraulic stowing is analyzed. Effects of roof bolting on strata control efficiency in steep coal mines employing AShchM systems are evaluated.

Application for trackless mining technique in Benxi uranium mine

International Nuclear Information System (INIS)

Chen Bingguo

1998-01-01

The author narrates the circumstances achieving constructional target in Benxi Uranium Mine under relying on advance of science and technology and adopting small trackless mining equipment, presents the application of trackless mining equipment at mining small mine and complex mineral deposit and discusses the unique superiority of trackless mining technique in development work, mining preparation work and backstoping

Mining engineer requirements in a German coal mine

Energy Technology Data Exchange (ETDEWEB)

Rauhut, F J

1985-10-01

Basic developments in German coal mines, new definitions of working areas of mining engineers, and groups of requirements in education are discussed. These groups include: requirements of hard-coal mining at great depth and in extended collieries; application of process technology and information systems in semi-automated mines; thinking in processes and systems; organizational changes; future requirements of mining engineers; responsibility of the mining engineer for employees and society.

Coal industry - memoranda

Energy Technology Data Exchange (ETDEWEB)

1986-01-01

This paper contains 41 memoranda submitted to the UK House of Commons Energy Committee containing views on the UK coal industry and responses to questions from the Select Committee. The following organizations are represented: Department of Energy; National Coal Board; APEX; BACM; NACODS; NUM; UDM; TUC; CEGB; Electricity Council; Northern Ireland Electricity Service; SSEB; British Gas Corporation; BP; Conoco (UK) Ltd.; Costain Mining Ltd.; Shell UK Ltd.; BSC; ICI; Boots; CBI; PSA; Solid Fuel Advisory Service; Domestic Coal Consumers Council; Associated Heat Services; Association of Shell Boilermakers; Babcock Power Ltd.; GEC; Foster Wheeler Power Products; ABMEC; British Longwall Mining Association; Federation of Civil Engineering Contractors; Federation of Small Mines of Great Britain; Chamber of Coal Traders; Coalfield Communities Campaign; Nottinghamshire County Council; Federation of Self-Employed and Small Businesses; the Colombian, Belgian and Netherlands Embassies; and Plaid Cymru.

Assessment of risk of accident at work as an indicator of safe behaviour of workers

Energy Technology Data Exchange (ETDEWEB)

Pisiewicz, K

1978-10-01

In 1977 the Psychology and Sociology Research Development Unit of the Central Mining Institute carried out research on the influence of assessment of the accident risk on the safe behaviour of workers. 450 workers employed at the longwall faces in 6 coal mines with various accident rates were questioned. It was found that a low assessment of risk favours hazardous operations, contrary to the principles of work safety, while a high assessment of the risk does not favour hazardous operations. Miners employed in coal mines with high accident rates tend to a low assessment of accident risk (arithmetic mean x 48.54) in comparison to miners from mines with low accident rates (arithmetic mean x 53.68). It was also found that the arithmetic mean of assessment of risks among workers who had had an accident at work is lower (x 50.3) than among workers who had not yet had an accident at work (x 55.32).

Mining Together : Large-Scale Mining Meets Artisanal Mining, A Guide for Action

OpenAIRE

World Bank

2009-01-01

The present guide mining together-when large-scale mining meets artisanal mining is an important step to better understanding the conflict dynamics and underlying issues between large-scale and small-scale mining. This guide for action not only points to some of the challenges that both parties need to deal with in order to build a more constructive relationship, but most importantly it sh...

Implementation of Paste Backfill Mining Technology in Chinese Coal Mines

Science.gov (United States)

Chang, Qingliang; Zhou, Huaqiang; Bai, Jianbiao

2014-01-01

Implementation of clean mining technology at coal mines is crucial to protect the environment and maintain balance among energy resources, consumption, and ecology. After reviewing present coal clean mining technology, we introduce the technology principles and technological process of paste backfill mining in coal mines and discuss the components and features of backfill materials, the constitution of the backfill system, and the backfill process. Specific implementation of this technology and its application are analyzed for paste backfill mining in Daizhuang Coal Mine; a practical implementation shows that paste backfill mining can improve the safety and excavation rate of coal mining, which can effectively resolve surface subsidence problems caused by underground mining activities, by utilizing solid waste such as coal gangues as a resource. Therefore, paste backfill mining is an effective clean coal mining technology, which has widespread application. PMID:25258737

Analysis characteristics determination of electrohydraulic control system operation to reduce the operation time of a powered roof support

Science.gov (United States)

Szurgacz, Dawid

2018-01-01

The article discusses basic functions of a powered roof support in a longwall unit. The support function is to provide safety by protecting mine workings against uncontrolled falling of rocks. The subject of the research includes the measures to shorten the time of roof support shifting. The roof support is adapted to transfer, in hazard conditions of rock mass tremors, dynamic loads caused by mining exploitation. The article presents preliminary research results on the time reduction of the unit advance to increase the extraction process and thus reduce operating costs. Conducted stand tests showed the ability to increase the flow for 3/2-way valve cartridges. The level of fluid flowing through the cartridges is adequate to control individual actuators.

30 CFR 819.21 - Auger mining: Protection of underground mining.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Auger mining: Protection of underground mining. 819.21 Section 819.21 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT... STANDARDS-AUGER MINING § 819.21 Auger mining: Protection of underground mining. Auger holes shall not extend...

Contract Mining versus Owner Mining – The Way Forward | Suglo ...

African Journals Online (AJOL)

Ghana Mining Journal ... By contracting out one or more of their mining operations, the mining companies can concentrate on their core businesses. This paper reviews ... The general trends in the mining industry show that contract mining will be the way forward for most mines under various circumstances in the future.

Selection of mining method for No.3 uranium ore body in the independent mining area at a uranium mine

International Nuclear Information System (INIS)

Ding Fulong; Ding Dexin; Ye Yongjun

2010-01-01

Mining operation in the existed mining area at a uranium mine is near completion and it is necessary to mine the No.3 uranium ore body in another mining area at the mine. This paper, based on the geological conditions, used analogical method for analyzing the feasible methods and the low cost and high efficiency mining method was suggested for the No.3 ore body in the independent mining area at the uranium mine. (authors)

Treatment of mine-water from decommissioning uranium mines

International Nuclear Information System (INIS)

Fan Quanhui

2002-01-01

Treatment methods for mine-water from decommissioning uranium mines are introduced and classified. The suggestions on optimal treatment methods are presented as a matter of experience with decommissioned Chenzhou Uranium Mine

30 CFR 77.1712 - Reopening mines; notification; inspection prior to mining.

Science.gov (United States)

2010-07-01

... to mining. 77.1712 Section 77.1712 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION... prior to mining. Prior to reopening any surface coal mine after it has been abandoned or declared... an authorized representative of the Secretary before any mining operations in such mine are...

Acid mine drainage: mining and water pollution issues in British Columbia

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-12-31

The importance of protecting water quality and some of the problems associated with mineral development are described. Negative impacts of mining operations such as sedimentation, water disturbances, and water pollution from waste rock and tailings are considered. Mining wastes, types of water pollution from mining, the legacy of acid mine drainage, predicting acid mine drainage, preventing and mitigating acid mine drainage, examples from the past, and cyanide heap-leaching are discussed. The real costs of mining at the Telkwa open pit coal mine are assessed. British Columbia mines that are known for or are potentially acid generating are shown on a map. 32 refs., 10 figs.

Responsible Mining: A Human Resources Strategy for Mine Development Project

OpenAIRE

Sampathkumar, Sriram (Ram)

2012-01-01

Mining is a global industry. Most mining companies operate internationally, often in remote, challenging environments and consequently frequently have respond to unusual and demanding Human Resource (HR) requirements. It is my opinion that the strategic imperative behind success in mining industry is responsible mining. The purpose of this paper is to examine how an effective HR strategy can be a competitive advantage that contributes to the success of a mining project in the global mining in...

Extending mine life

International Nuclear Information System (INIS)

Anon.

1984-01-01

Mine layouts, new machines and techniques, research into problem areas of ground control and so on, are highlighted in this report on extending mine life. The main resources taken into account are coal mining, uranium mining, molybdenum and gold mining

MONITORING OF MINING

Directory of Open Access Journals (Sweden)

Berislav Šebečić

1996-12-01

Full Text Available The way mining was monitored in the past depended on knowledge, interest and the existing legal regulations. Documentary evidence about this work can be found in archives, libraries and museums. In particular, there is the rich archival material (papers and books concerning the work of the one-time Imperial and Royal Mining Captaincies in Zagreb, Zadar, Klagenfurt and Split, A minor part of the documentation has not yet been transferred to Croatia. From mining handbooks and books we can also find out about mining in Croatia. In the context of Austro-Hungary. For example, we can find out that the first governorships in Zagreb and Zadar headed the Ban, Count Jelacic and Baron Mamula were also the top mining authorities, though this, probably from political motives, was suppressed in the guides and inventories or the Mining Captaincies. At the end of the 1850s, Croatia produced 92-94% of sea salt, up to 8.5% of sulphur, 19.5% of asphalt and 100% of oil for the Austro-Hungarian empire. From data about mining in the Split Mining Captaincy, prepared for the Philadephia Exhibition, it can be seen that in the exploratory mining operations in which there were 33,372 independent mines declared in 1925 they were looking mainly for bauxite (60,0%, then dark coal (19,0%, asphalts (10.3% and lignites (62%. In 1931, within the area covered by the same captaincy, of 74 declared mines, only 9 were working. There were five coal mines, three bauxite mines and one for asphalt. I suggest that within state institution, the Mining Captaincy or Authority be renewed, or that a Mining and Geological Authority be set ap, which would lead to the more complete affirmation of Croatian mining (the paper is published in Croatian.

Gold-Mining

DEFF Research Database (Denmark)

Raaballe, J.; Grundy, B.D.

2002-01-01

  Based on standard option pricing arguments and assumptions (including no convenience yield and sustainable property rights), we will not observe operating gold mines. We find that asymmetric information on the reserves in the gold mine is a necessary and sufficient condition for the existence...... of operating gold mines. Asymmetric information on the reserves in the mine implies that, at a high enough price of gold, the manager of high type finds the extraction value of the company to be higher than the current market value of the non-operating gold mine. Due to this under valuation the maxim of market...

Control over surrounding rocks deformation of soft floor and whole-coal gateways with trapezoidal supports

Energy Technology Data Exchange (ETDEWEB)

Zhai, X.; Li, D.; Shao, Q.; Sun, Y. [Henan Polytechnic University, Jaozuo (China). Dept. of Resource and Material Engineering

2005-06-01

The coal seams of Guengcun Coal mine of Yima Coal Group Co. Ltd. are prone to spontaneous combustion. Fully mechanized longwall mining with sublevel caving is used as the mining method. Based on the characteristics of the gateways of the 1301 coal face and of the roof coal seams, the natural equilibrium arch theory was used to design the parameters of 11 mine-type metal supports. Then, in-situ supporting experiments were carried out. The results indicate that under the action of virgin rock stress, the width of broken rocks zone of surrounding rocks is 1.7-2.0 m in the return heading and 1.1-1.3 m in the outgoing headway and their surrounding rocks belong to the IV-type soft rock and the III-type common surrounding rock respectively. Therefore, under the movable abutment pressure, the gateway deformation is serious. At the same time, the accumulated water on gateway floor must be drained in time. These measures were taken in the 1302 and 1304 coal faces in Gengcun colliery, and satisfactory results have been obtained. 8 refs., 3 figs.

The mining methods at the Fraisse mine

International Nuclear Information System (INIS)

Heurley, P.; Vervialle, J.P.

1985-01-01

The Fraisse mine is one of the four underground mines of the La Crouzille mining divisions of Cogema. Faced with the necessity to mechanize its workings, this mine also had to satisfy a certain number of stringent demands. This has led to concept of four different mining methods for the four workings at present in active operation at this pit, which nevertheless preserve the basic ideas of the methods of top slicing under concrete slabs (TSS) or horizontal cut-and-fill stopes (CFS). An electric scooptram is utilized. With this type of vehicle the stringent demands for the introduction of means for fire fighting and prevention are reduced to a minimum. Finally, the dimensions of the vehicles and the operation of these methods result in a net-to-gross tonnages of close to 1, i.e. a maximum output, combined with a minimum of contamination [fr

Angles of total shifts and angles of maxumum crop during development of faces diagonal to seam strike directions

Directory of Open Access Journals (Sweden)

Н. А. Колесник

2017-06-01

Full Text Available When predicting deformations and determining measures to protect underworked objects, angular parameters are used: the boundary angles, the angles of total shift, the angle of maximum crop. The values of these angular parameters are given in the normative documents, but only for sections across and along the strike of the formation. However, at present, longwall face mining is mainly being carried out along a diagonal direction to the strike of the formation. In connection with this, the determination of the values of the angular parameters for such conditions is a topical task.The method of determination and the analytical dependences of the angles of total shifts and angles of maximum crop in sections of the longitudinal and transverse axes of coal-mining faces developed along diagonal directions to the strike of the formation are proposed. These angular parameters are used for prognosis of deformations of the earth's surface and for determining the characteristic zones of influence of mine workings on the local places.

GPK helmets protecting from gas and dusts

Energy Technology Data Exchange (ETDEWEB)

Il' inskii, Eh.G.; Kogan, Yu.A.; Mazanenko, V.P.

1983-08-01

The GPK protective helmet with an integrated respirator system protecting a miner's respiratory system and eyes from gases and dusts is described. The system uses compressed air from the mine compressed air system. Air is supplied to the respirator by an elastic rubber pipe to 30 m long. The air cools the miner's head under the helmet and passes between a protective shield and the miner's face protecting eyes and the respiratory system. Air supply ranges from 100 to 150 l/min. The air supplied to the respirator is cleaned by a filter. The GPK system weighs 1.2 kg. The system has been tested under laboratory conditions and in two coal mines under operational conditions at longwall faces and during mine drivage. Tests showed that the GPK guarantees efficient cooling and protection from dust. Design of the GPK helmet with a respirator is shown in two schemes. Technical specifications of the system are given.

Effect of longwall face advance rate on spontaneous heating process in the gob area - CFD modelling

Czech Academy of Sciences Publication Activity Database

Taraba, B.; Michalec, Zdeněk

2011-01-01

Roč. 90, č. 8 (2011), s. 2790-2797 ISSN 0016-2361 R&D Projects: GA ČR GA105/06/0630 Grant - others:GA ČR(CZ) GA105/08/1414 Institutional research plan: CEZ:AV0Z30860518 Keywords : coal oxidation * spontaneous heating * CFD modelling * Fluent Subject RIV: DH - Mining, incl. Coal Mining Impact factor: 3.248, year: 2011 http://www.sciencedirect.com/science/article/pii/S0016236111001724

Mined-out land

International Nuclear Information System (INIS)

Reinsalu, Enno; Toomik, Arvi; Valgma, Ingo

2002-01-01

Estonian mineral resources are deposited in low depth and mining fields are large, therefore vast areas are affected by mining. There are at least 800 deposits with total area of 6,000 km 2 and about the same number of underground mines, surface mines, peat fields, quarries, and sand and gravel pits. The deposits cover more than 10% of Estonian mainland. The total area of operating mine claims exceeds 150 km 2 that makes 0.3 % of Estonian area. The book is written mainly for the people who are living or acting in the area influenced by mining. The observations and research could benefit those who are interested in geography and environment, who follow formation and look of mined-out landscapes. The book contains also warnings for careless people on and under the surface of the mined-out land. Part of the book contains results of the research made in 1968-1993 by the first two authors working at the Estonian branch of A.Skochinsky Institute of Mining. Since 1990, Arvi Toomik continued this study at the Northeastern section of the Institute of Ecology of Tallinn Pedagogical University. Enno Reinsalu studied aftereffects of mining at the Mining Department of Tallinn Technical University from 1998 to 2000. Geographical Information System for Mining was studied by Ingo Valgma within his doctoral dissertation, and this book is one of the applications of his study

Trust Mines

Science.gov (United States)

The United States and the Navajo Nation entered into settlement agreements that provide funds to conduct investigations and any needed cleanup at 16 of the 46 priority mines, including six mines in the Northern Abandoned Uranium Mine Region.

Web Mining

Science.gov (United States)

Fürnkranz, Johannes

The World-Wide Web provides every internet citizen with access to an abundance of information, but it becomes increasingly difficult to identify the relevant pieces of information. Research in web mining tries to address this problem by applying techniques from data mining and machine learning to Web data and documents. This chapter provides a brief overview of web mining techniques and research areas, most notably hypertext classification, wrapper induction, recommender systems and web usage mining.

Data mining, mining data : energy consumption modelling

Energy Technology Data Exchange (ETDEWEB)

Dessureault, S. [Arizona Univ., Tucson, AZ (United States)

2007-09-15

Most modern mining operations are accumulating large amounts of data on production and business processes. Data, however, provides value only if it can be translated into information that appropriate users can utilize. This paper emphasized that a new technological focus should emerge, notably how to concentrate data into information; analyze information sufficiently to become knowledge; and, act on that knowledge. Researchers at the Mining Information Systems and Operations Management (MISOM) laboratory at the University of Arizona have created a method to transform data into action. The data-to-action approach was exercised in the development of an energy consumption model (ECM), in partnership with a major US-based copper mining company, 2 software companies, and the MISOM laboratory. The approach begins by integrating several key data sources using data warehousing techniques, and increasing the existing level of integration and data cleaning. An online analytical processing (OLAP) cube was also created to investigate the data and identify a subset of several million records. Data mining algorithms were applied using the information that was isolated by the OLAP cube. The data mining results showed that traditional cost drivers of energy consumption are poor predictors. A comparison was made between traditional methods of predicting energy consumption and the prediction formed using data mining. Traditionally, in the mines for which data were available, monthly averages of tons and distance are used to predict diesel fuel consumption. However, this article showed that new information technology can be used to incorporate many more variables into the budgeting process, resulting in more accurate predictions. The ECM helped mine planners improve the prediction of energy use through more data integration, measure development, and workflow analysis. 5 refs., 11 figs.

Mining with communities

International Nuclear Information System (INIS)

Veiga, Marcello M.; Scoble, Malcolm; McAllister, Mary Louise

2001-01-01

To be considered as sustainable, a mining community needs to adhere to the principles of ecological sustainability, economic vitality and social equity. These principles apply over a long time span, covering both the life of the mine and post-mining closure. The legacy left by a mine to the community after its closure is emerging as a significant aspect of its planning. Progress towards sustainability is made when value is added to a community with respect to these principles by the mining operation during its life cycle. This article presents a series of cases to demonstrate the diverse potential challenges to achieving a sustainable mining community. These case studies of both new and old mining communities are drawn mainly from Canada and from locations abroad where Canadian companies are now building mines. The article concludes by considering various approaches that can foster sustainable mining communities and the role of community consultation and capacity building. (author)

Ideate about building green mine of uranium mining and metallurgy

International Nuclear Information System (INIS)

Shi Zuyuan

2012-01-01

Analysing the current situation of uranium mining and metallurgy; Setting up goals for green uranium mining and metallurgy, its fundamental conditions, Contents and measures. Putting forward an idea to combine green uranium mining and metallurgy with the state target for green mining, and keeping its own characteristics. (author)

Social big data mining

CERN Document Server

Ishikawa, Hiroshi

2015-01-01

Social Media. Big Data and Social Data. Hypotheses in the Era of Big Data. Social Big Data Applications. Basic Concepts in Data Mining. Association Rule Mining. Clustering. Classification. Prediction. Web Structure Mining. Web Content Mining. Web Access Log Mining, Information Extraction and Deep Web Mining. Media Mining. Scalability and Outlier Detection.

Mining and mining authorities in Saarland 2016. Mining economy, mining technology, occupational safety, environmental protection, statistics, mining authority activities. Annual report; Bergbau und Bergbehoerden im Saarland 2016. Bergwirtschaft, Bergtechnik, Arbeitsschutz, Umweltschutz, Statistiken, Taetigkeiten der Bergbehoerden. Jahresbericht

Energy Technology Data Exchange (ETDEWEB)

NONE

2016-07-01

The annual report of the Saarland Upper Mining Authority provides an insight into the activities of mining authorities. Especially, the development of the black coal mining, safety and technology of mining as well as the correlation between mining and environment are stressed.

Numerical simulation of head top coal's stability control of fully mechanized longwall mining with sublevel caving face in large dip seam

Energy Technology Data Exchange (ETDEWEB)

Li, W.; Wan, Z.; Jiang, F.; Jia, P. [Beijing Science and Technology University, Beijing (China)

2008-07-01

Stability control of the head face's top-coal is one of the key techniques of realising high production and high efficiency in coal mining in fully mechanized top-coal caving face. The characteristics of the stress in the overlying strata of the fully mechanized top-coal caving face and the top coal were analysed using FLAC{sup 3D}. The results show that the tip-to-face top-coal generates a large deformation while it is in the stress-relaxed area. The top-coal in the front of the wall appears to be the failure area for the effect of the abutment pressure that spreads over the coal seam. The surrounding rock of the upper face end is the key part strengthened the control of the rib spalling. The first and frequent appearing phenomenon of losing stability of the powered supports is that the back base of the hydraulic power supports in the top of the face slips. Increasing the quality of support and so on can maintain the stability of surrounding rock. 4 refs., 7 figs., 1 tab.

75 FR 17529 - High-Voltage Continuous Mining Machine Standard for Underground Coal Mines

Science.gov (United States)

2010-04-06

... High-Voltage Continuous Mining Machine Standard for Underground Coal Mines AGENCY: Mine Safety and... of high-voltage continuous mining machines in underground coal mines. It also revises MSHA's design...-- Underground Coal Mines III. Section-by-Section Analysis A. Part 18--Electric Motor-Driven Mine Equipment and...

Review of subsidence and stabilization techniques

International Nuclear Information System (INIS)

Fernando, D.A.

1988-01-01

In Britain the damage caused by underground coal mining operations approximates to about 100 million pounds Sterling per annum, most of the damage resulting from longwall mining operations. Causes of subsidence can be attributed to the following factors: (1) roof failure (2) pillar failure (3) floor movements. Currently, in Britain, the mining industry is undergoing a state of decline for economic reasons. Consequently, the number of old coal sites available for development schemes has increased. Therefore, the problems associated with subsidence can be segregated into two parts. The first being the mitigation of the effects of subsidence on structures on actively mined areas. The second being the stabilization and rehabilitation of ground over and around old mine sites for new development schemes. In the former case the stabilization techniques employed may be local or global, depending on the problems encountered in any particular area. In the latter case, generally, grouting techniques are employed. This paper aims to review the causes of subsidence and the techniques used to minimize its effect on structures. Also, more economic alternative methods of ground stabilization techniques are described and proposed, to be used in this area of ground engineering

Mine water treatment

Energy Technology Data Exchange (ETDEWEB)

Komissarov, S V

1980-10-01

This article discusses composition of chemical compounds dissolved or suspended in mine waters in various coal basins of the USSR: Moscow basin, Kuzbass, Pechora, Kizelovsk, Karaganda, Donetsk and Chelyabinsk basins. Percentage of suspended materials in water depending on water source (water from water drainage system of dust suppression system) is evaluated. Pollution of mine waters with oils and coli bacteria is also described. Recommendations on construction, capacity of water settling tanks, and methods of mine water treatment are presented. In mines where coal seams 2 m or thicker are mined a system of two settling tanks should be used: in the upper one large grains are settled, in the lower one finer grains. The upper tank should be large enough to store mine water discharged during one month, and the lower one to store water discharged over two months. Salty waters from coal mines mining thin coal seams should be treated in a system of water reservoirs from which water evaporates (if climatic conditions permit). Mine waters from mines with thin coal seams but without high salt content can be treated in a system of long channels with water plants, which increase amount of oxygen in treated water. System of biological treatment of waste waters from mine wash-houses and baths is also described. Influence of temperature, sunshine and season of the year on efficiency of mine water treatment is also assessed. (In Russian)

Uranium mining

International Nuclear Information System (INIS)

2008-01-01

Full text: The economic and environmental sustainability of uranium mining has been analysed by Monash University researcher Dr Gavin Mudd in a paper that challenges the perception that uranium mining is an 'infinite quality source' that provides solutions to the world's demand for energy. Dr Mudd says information on the uranium industry touted by politicians and mining companies is not necessarily inaccurate, but it does not tell the whole story, being often just an average snapshot of the costs of uranium mining today without reflecting the escalating costs associated with the process in years to come. 'From a sustainability perspective, it is critical to evaluate accurately the true lifecycle costs of all forms of electricity production, especially with respect to greenhouse emissions, ' he says. 'For nuclear power, a significant proportion of greenhouse emissions are derived from the fuel supply, including uranium mining, milling, enrichment and fuel manufacture.' Dr Mudd found that financial and environmental costs escalate dramatically as the uranium ore is used. The deeper the mining process required to extract the ore, the higher the cost for mining companies, the greater the impact on the environment and the more resources needed to obtain the product. I t is clear that there is a strong sensitivity of energy and water consumption and greenhouse emissions to ore grade, and that ore grades are likely to continue to decline gradually in the medium to long term. These issues are critical to the current debate over nuclear power and greenhouse emissions, especially with respect to ascribing sustainability to such activities as uranium mining and milling. For example, mining at Roxby Downs is responsible for the emission of over one million tonnes of greenhouse gases per year and this could increase to four million tonnes if the mine is expanded.'

Requirements and opportunities for mining engineers in the mining industry abroad

Energy Technology Data Exchange (ETDEWEB)

Albrecht, E

1987-04-09

The decline of the German mining industry and the increasing industrialization of mining is forcing ever greater numbers of young German mining graduates to build their careers abroad. The requirements for this - apart from the technical qualifications are a good knowledge of foreign languages and a readiness to leave Germany for a long time, even for ever. If the young mining graduate accepts these conditions, numerous professional opportunities will open up for him, both with German mining companies with interests abroad, in mining supply companies and consultancy firms and with foreign companies. 6 references.

Mechanical solution of the maximum point of dynamic abutment pressure under deep long-wall working face

Energy Technology Data Exchange (ETDEWEB)

Jiang, F.; Ma, Q. [Shandong University of Science and Technology, Tai' an (China). College of Resource and Environmental Engineering

2002-06-01

The paper studies the dynamic relationship between abutment pressure and overburden collapse precess with advancing of working face. The result shows that the abutment pressure reaches its maximum value when the working face dimension is 1.27 times of the mining depth. This result confirms the statistical result from the strata movement surveys that overburden reaches its full movement stage when extracting dimension reaches 1.2 1.4 times of the mining depth. 12 refs., 2 figs.

Mining

Directory of Open Access Journals (Sweden)

Khairullah Khan

2014-09-01

Full Text Available Opinion mining is an interesting area of research because of its applications in various fields. Collecting opinions of people about products and about social and political events and problems through the Web is becoming increasingly popular every day. The opinions of users are helpful for the public and for stakeholders when making certain decisions. Opinion mining is a way to retrieve information through search engines, Web blogs and social networks. Because of the huge number of reviews in the form of unstructured text, it is impossible to summarize the information manually. Accordingly, efficient computational methods are needed for mining and summarizing the reviews from corpuses and Web documents. This study presents a systematic literature survey regarding the computational techniques, models and algorithms for mining opinion components from unstructured reviews.

PREVENTION OF ACID MINE DRAINAGE GENERATION FROM OPEN-PIT MINE HIGHWALLS

Science.gov (United States)

Exposed, open pit mine highwalls contribute significantly to the production of acid mine drainage (AMD) thus causing environmental concerns upon closure of an operating mine. Available information on the generation of AMD from open-pit mine highwalls is very limit...

A direction of developing a mining method and mining complexes

Energy Technology Data Exchange (ETDEWEB)

Gabov, V.V.; Efimov, I.A. [St. Petersburg State Mining Institute, St. Petersburg (Russian Federation). Vorkuta Branch

1996-12-31

The analyses of a mining method as a main factor determining the development stages of mining units is presented. The paper suggests a perspective mining method which differs from the known ones by following peculiarities: the direction selectivity of cuts with regard to coal seams structure; the cutting speed, thickness and succession of dusts. This method may be done by modulate complexes (a shield carrying a cutting head for coal mining), their mining devices being supplied with hydraulic drive. An experimental model of the module complex has been developed. 2 refs.

30 CFR 780.27 - Reclamation plan: Surface mining near underground mining.

Science.gov (United States)

2010-07-01

... 30 Mineral Resources 3 2010-07-01 2010-07-01 false Reclamation plan: Surface mining near underground mining. 780.27 Section 780.27 Mineral Resources OFFICE OF SURFACE MINING RECLAMATION AND ENFORCEMENT, DEPARTMENT OF THE INTERIOR SURFACE COAL MINING AND RECLAMATION OPERATIONS PERMITS AND COAL...

Minimizing the Impact of Mining Activities for Sustainable Mined-Out ...

African Journals Online (AJOL)

Minimizing the Impact of Mining Activities for Sustainable Mined-Out Area ... sensing and Geographical Information System (GIS) in assessing environmental impact of ... Keywords: Solid mineral, Impact assessment, Mined-out area utilization, ...

Archveyor{trademark} automated mining system - implementation at the Conant mine

Energy Technology Data Exchange (ETDEWEB)

Hofmann, W.J. [Arch of Illinois, Percy, IL (United States)

1997-12-01

Arch Mineral Corporation, through the Arch Technology Department, has developed an automated continuous haulage mining system called the `Archveyor{trademark}`. The original technology came from a Russian patent. Kloeckner-Becorit (K-B) further developed the system and called it the `Mobile Conveyor`. This system was utilized in both coal and trona mines in the United States and Canada. Consolidation Coal designed their version of this continuous haulage system, called the `Tramveyor`. The Tramveyor is presently operating in their Dilworth Mine, in Pennsylvania. This system has no computer guidance system related to the continuous miner or the Tramveyor. Arch Mineral Corporation has further developed this continuous haulage mining system. Their system is a programmable, logic-controlled (PLC) automated mining system. A highwall version of the Archveyor{trademark} is being operated at Arch of Wyoming near Hanna, Wyoming. This paper introduces the first underground version of Archveyor{trademark} to be implemented at Conant Mine in southern Illinois. During the development process, the Archveyor{trademark} mining system consists of a continuous miner, a bolter car, the Archveyor{trademark} (itself), a stageloader, and an operator`s cab. During the secondary mining process the bolter car is taken out of the system.

Management of mining-related damages in abandoned underground coal mine areas using GIS

International Nuclear Information System (INIS)

Lee, U.J.; Kim, J.A.; Kim, S.S.; Kim, W.K.; Yoon, S.H.; Choi, J.K.

2005-01-01

The mining-related damages such as ground subsidence, acid mine drainage (AMD), and deforestation in the abandoned underground coal mine areas become an object of public concern. Therefore, the system to manage the mining-related damages is needed for the effective drive of rehabilitation activities. The management system for Abandoned Underground Coal Mine using GIS includes the database about mining record and information associated with the mining-related damages and application programs to support mine damage prevention business. Also, this system would support decision-making policy for rehabilitation and provide basic geological data for regional construction works in abandoned underground coal mine areas. (authors)

Text Mining.

Science.gov (United States)

Trybula, Walter J.

1999-01-01

Reviews the state of research in text mining, focusing on newer developments. The intent is to describe the disparate investigations currently included under the term text mining and provide a cohesive structure for these efforts. A summary of research identifies key organizations responsible for pushing the development of text mining. A section…

Surface mining

Science.gov (United States)

Robert Leopold; Bruce Rowland; Reed Stalder

1979-01-01

The surface mining process consists of four phases: (1) exploration; (2) development; (3) production; and (4) reclamation. A variety of surface mining methods has been developed, including strip mining, auger, area strip, open pit, dredging, and hydraulic. Sound planning and design techniques are essential to implement alternatives to meet the myriad of laws,...

Uranium mining

International Nuclear Information System (INIS)

Lange, G.

1975-01-01

The winning of uranium ore is the first stage of the fuel cycle. The whole complex of questions to be considered when evaluating the profitability of an ore mine is shortly outlined, and the possible mining techniques are described. Some data on uranium mining in the western world are also given. (RB) [de

Realizatinon of “zero emission” of mining water effluents from Sasa mine

OpenAIRE

Mirakovski, Dejan; Doneva, Nikolinka; Hadzi-Nikolova, Marija; Gocevski, Borce

2015-01-01

Sasa mine continuously takes actions to minimize the environmental impact of mining activities, in order to fulfill the national legislation in the field of environmental protection which comply with European legislation. This paper shows the drainage system of the horizon 830, which is performed in order to prevent free leakage of mining groundwater, as a part of these actions. This system provides a zero emission of mining water in the environment from Sasa mine. Key words: mining water...

Sustainable rehabilitation of mining waste and acid mine drainage using geochemistry, mine type, mineralogy, texture, ore extraction and climate knowledge.

Science.gov (United States)

Anawar, Hossain Md

2015-08-01

The oxidative dissolution of sulfidic minerals releases the extremely acidic leachate, sulfate and potentially toxic elements e.g., As, Ag, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Th, U, Zn, etc. from different mine tailings and waste dumps. For the sustainable rehabilitation and disposal of mining waste, the sources and mechanisms of contaminant generation, fate and transport of contaminants should be clearly understood. Therefore, this study has provided a critical review on (1) recent insights in mechanisms of oxidation of sulfidic minerals, (2) environmental contamination by mining waste, and (3) remediation and rehabilitation techniques, and (4) then developed the GEMTEC conceptual model/guide [(bio)-geochemistry-mine type-mineralogy- geological texture-ore extraction process-climatic knowledge)] to provide the new scientific approach and knowledge for remediation of mining wastes and acid mine drainage. This study has suggested the pre-mining geological, geochemical, mineralogical and microtextural characterization of different mineral deposits, and post-mining studies of ore extraction processes, physical, geochemical, mineralogical and microbial reactions, natural attenuation and effect of climate change for sustainable rehabilitation of mining waste. All components of this model should be considered for effective and integrated management of mining waste and acid mine drainage. Copyright © 2015 Elsevier Ltd. All rights reserved.

Philippine Mining Capitalism: The Changing Terrains of Struggle in the Neoliberal Mining Regime

Directory of Open Access Journals (Sweden)

Alvin A. Camba

2016-06-01

Full Text Available This article analyzes how the mining sector and anti-mining groups compete for mining outcomes in the Philippines. I argue that the transition to a neoliberal mineral regime has empowered the mining sector and weakened the mining groups by shifting the terrains of struggle onto the domains of state agencies and scientific networks. Since the neoliberal era, the mining sector has come up with two strategies. First, technologies of subjection elevate various public institutions to elect and select the processes aimed at making mining accountable and sensitive to the demands of local communities. However, they often refuse or lack the capacity to intervene effectively. Second, technologies of subjectivities allow a selective group of industry experts to single-handedly determine the environmental viability of mining projects. Mining consultants, specialists, and scientists chosen by mining companies determine the potential environmental damage on water bodies, air pollution, and soil erosion. Because of the mining capital’s access to economic and legal resources, anti-mining communities across the Philippines have been forced to compete on an unequal terrain for a meaningful social dialogue and mining outcomes.

Technological highwall mining

Energy Technology Data Exchange (ETDEWEB)

Davison, I. [Highwall Systems (United States)

2006-09-15

The paper explores the issues facing highwall mining. Based in Chilhowie, Virginia, American Highwall Systems has developed a highwall mining system that will allow the mining of coal seams from 26 in to 10 ft in thickness. The first production model, AH51, began mining in August 2006. Technologies incorporated into the company's mining machines to improve the performance, enhance the efficiency, and improve the reliability of the highwall mining equipment incorporate technologies from many disciplines. Technology as applied to design engineering, manufacturing and fabrication engineering, control and monitoring computer hardware and software has played an important role in the evolution of the American Highwall Systems design concept. 5 photos.

Kiruna research mine

Energy Technology Data Exchange (ETDEWEB)

Oestensen, A

1983-12-01

The research mine at Kiruna is the first large-scale mining research project sponsored by the Swedish government. Under the leadership of the Swedish Mining Research Foundation, a five-year project involving development of new mining systems and machinery will be carried out in cooperation with the Lulea Institute of Technology and a number of Swedish industrial companies.

Overview of mine drainage geochemistry at historical mines, Humboldt River basin and adjacent mining areas, Nevada. Chapter E.

Science.gov (United States)

Nash, J. Thomas; Stillings, Lisa L.

2004-01-01

Reconnaissance hydrogeochemical studies of the Humboldt River basin and adjacent areas of northern Nevada have identified local sources of acidic waters generated by historical mine workings and mine waste. The mine-related acidic waters are rare and generally flow less than a kilometer before being neutralized by natural processes. Where waters have a pH of less than about 3, particularly in the presence of sulfide minerals, the waters take on high to extremely high concentrations of many potentially toxic metals. The processes that create these acidic, metal-rich waters in Nevada are the same as for other parts of the world, but the scale of transport and the fate of metals are much more localized because of the ubiquitous presence of caliche soils. Acid mine drainage is rare in historical mining districts of northern Nevada, and the volume of drainage rarely exceeds about 20 gpm. My findings are in close agreement with those of Price and others (1995) who estimated that less than 0.05 percent of inactive and abandoned mines in Nevada are likely to be a concern for acid mine drainage. Most historical mining districts have no draining mines. Only in two districts (Hilltop and National) does water affected by mining flow into streams of significant size and length (more than 8 km). Water quality in even the worst cases is naturally attenuated to meet water-quality standards within about 1 km of the source. Only a few historical mines release acidic water with elevated metal concentrations to small streams that reach the Humboldt River, and these contaminants and are not detectable in the Humboldt. These reconnaissance studies offer encouraging evidence that abandoned mines in Nevada create only minimal and local water-quality problems. Natural attenuation processes are sufficient to compensate for these relatively small sources of contamination. These results may provide useful analogs for future mining in the Humboldt River basin, but attention must be given to

Hazard control at the workplace; Maitriser le risque au poste de travail

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-12-31

A total of 78 papers were presented at the symposium in four sections: a general section entitled risk analysis and appropriate prevention strategies, and three workshops entitled: measuring atmospheric pollution at the workplace - biological monitoring; personal protective equipment: effectiveness and ergonomics; and changing technologies and human reliability in production systems. Opening addresses, reports on each workshop, and a summary of the round table and discussions, and closing remarks are included in the proceedings. Two papers are of particular relevance to the coal industry. They are entitled: `Using computer simulation to analyze risk in longwall mine emergency evacuations` by A.F. Glowacki of the US Bureau of Mines, Pittsburgh, PA, USA and `Determination of the urinary excretion of metabolites of polycyclic aromatic hydrocarbons by coke plant workers` by G. Grimmer, K.-W. Naujack and G. Dettbarn of The Biochemisches Institut fuer Unweltcarcinogene, Grosshansdorf, Germany.

Present and future mine effluents management at Zirovski Vrh uranium mine

International Nuclear Information System (INIS)

Logar, Z.; Likar, B.; Gantar, I.

2002-01-01

Zirovski Vrh uranium mine and its facilities are situated on the northeastern slopes of the Zirovski Vrh ridge (960 m) and on the southern slopes of Crna gora (611 m) respectively. Mine elevation is from 430 m (bottom of the valley) to 580 m (P-1 adit). All effluents from the mine and mill objects flow into the Brebovscica river (with average yearly flow of 0.74 m 3 /s): run off mine water; mine waste pile Jazbec outflow; mill tailings Borst outflows; effluents from mine temporary mine waste piles P-1, P-9, P-36 are of minor significance. The first three effluents and the recipient surface water flows (the Todrascica brook and the Brebovscica river) are monitored extensively. The impact of radioactive polluted outflows on named waters is proved, but far under the maximal permitted limit values. The authorised maximal limits values for mine effluents were obtained in 1996. Detail design will ensure that this values will not be exceeded in the future. The long term planes are to minimise the uranium concentrations in the run off mine water by target underground drilling. The mine waste pile and the mill tailings will be covered by engineered cover system to avoid clean water contamination by weathering and ablution as well. The existing effluents from the mill tailings will diminish after the remediation and consolidation of the tailing. The Government of Slovenia funds the remediation of the uranium production site Zirovski Vrh. Estimated needed funds for remediation of the main objects are shown in the table below. The total investment includes also the costs for effluents control. Area Mio US$ Underground mine remediation 19.00 Mine waste pile remediation 6.50 Mill tailings remediation 2.24 Total investment costs 27.74 Above figures do not include operation costs of the Zirovski Vrh Mine, approximately US$ 2.2 Mio per year nowadays. The last implementation schedule foresights the end of remediation works in year 2005. After that starts trial monitoring of 5 years

Hydrogeochemical assessment of mine-impacted water and sediment of iron ore mining

Science.gov (United States)

Nur Atirah Affandi, Fatin; Kusin, Faradiella Mohd; Aqilah Sulong, Nur; Madzin, Zafira

2018-04-01

This study was carried out to evaluate the hydrogeochemical behaviour of mine-impacted water and sediment of a former iron ore mining area. Sampling of mine water and sediment were carried out at selected locations within the mine including the former mining ponds, mine tailings and the nearby stream. The water samples were analysed for their hydrochemical facies, major and trace elements including heavy metals. The water in the mining ponds and the mine tailings was characterised as highly acidic (pH 2.54-3.07), but has near-neutral pH in the nearby stream. Results indicated that Fe and Mn in water have exceeded the recommended guidelines values and was also supported by the results of geochemical modelling. The results also indicated that sediments in the mining area were contaminated with Cd and As as shown by the potential ecological risk index values. The total risk index of heavy metals in the sediment were ranked in the order of Cd>As>Pb>Cu>Zn>Cr. Overall, the extent of potential ecological risks of the mining area were categorised as having low to moderate ecological risk.

Collaborative Data Mining

Science.gov (United States)

Moyle, Steve

Collaborative Data Mining is a setting where the Data Mining effort is distributed to multiple collaborating agents - human or software. The objective of the collaborative Data Mining effort is to produce solutions to the tackled Data Mining problem which are considered better by some metric, with respect to those solutions that would have been achieved by individual, non-collaborating agents. The solutions require evaluation, comparison, and approaches for combination. Collaboration requires communication, and implies some form of community. The human form of collaboration is a social task. Organizing communities in an effective manner is non-trivial and often requires well defined roles and processes. Data Mining, too, benefits from a standard process. This chapter explores the standard Data Mining process CRISP-DM utilized in a collaborative setting.

76 FR 63238 - Proximity Detection Systems for Continuous Mining Machines in Underground Coal Mines

Science.gov (United States)

2011-10-12

... Detection Systems for Continuous Mining Machines in Underground Coal Mines AGENCY: Mine Safety and Health... Agency's proposed rule addressing Proximity Detection Systems for Continuous Mining Machines in... proposed rule for Proximity Detection Systems on Continuous Mining Machines in Underground Coal Mines. Due...

76 FR 70075 - Proximity Detection Systems for Continuous Mining Machines in Underground Coal Mines

Science.gov (United States)

2011-11-10

... Detection Systems for Continuous Mining Machines in Underground Coal Mines AGENCY: Mine Safety and Health... proposed rule addressing Proximity Detection Systems for Continuous Mining Machines in Underground Coal... Detection Systems for Continuous Mining Machines in Underground Coal Mines. MSHA conducted hearings on...

Determine Appropriate Post Mining Land Use in Indonesia Coal Mining Using Land Suitability Evaluation

OpenAIRE

Maryati, Sri; Shimada, Hideki; Hamanaka, Akihiro; Sasaoka, Takashi; Matsui, Kikuo

2012-01-01

Coal mining industry gives many benefits for Indonesia including contribution in total Indonesian GDP. Most of coal mines in Indonesia are open pit mining method which disturbs large area of land. One of open pit mining impact is damage land and related to soil erosion occurrences it will degrade land by top soil loses. Indonesia Government has issued mine closure regulation to encourage mining industry provide post mining land use. Determination of post mining land use should be considering ...

A guide to mines and mining houses of the Republic of South Africa

Energy Technology Data Exchange (ETDEWEB)

1989-02-01

This guide lists the mining houses of the Republic of South Africa and the mines under their respective control. It is intended as a guide for British exporters wishing to develop business with the South African mining industry and hence includes buying offices and senior buying personnel in South Africa (and in the UK where relevant). Amongst the 16 mining houses included are the Chamber of Mines of South Africa, De Beers Consolidated Mines Ltd., Rand Mines Ltd., Sasol Ltd. and the South African Iron and Steel Industrial Corporation Ltd.

Numerical Study on 4-1 Coal Seam of Xiaoming Mine in Ascending Mining

Science.gov (United States)

Tianwei, Lan; Hongwei, Zhang; Sheng, Li; Weihua, Song; Batugin, A. C.; Guoshui, Tang

2015-01-01

Coal seams ascending mining technology is very significant, since it influences the safety production and the liberation of dull coal, speeds up the construction of energy, improves the stability of stope, and reduces or avoids deep hard rock mining induced mine disaster. Combined with the Xiaoming ascending mining mine 4-1, by numerical calculation, the paper analyses ascending mining 4-1 factors, determines the feasibility of ascending mining 4-1 coalbed, and proposes roadway layout program about working face, which has broad economic and social benefits. PMID:25866840

Ghana Mining Journal

African Journals Online (AJOL)

... in the Ghana mining journal: Geology and Mineral Exploration, Mining, Quarrying, Geomechanics, Groundwater Studies, Hydrocarbon Development, Mineral Processing, Metallurgy, Material Science, Mineral Management Policies, Mineral Economics, Environmental Aspects, Computer Applications and Mining Education.

Legal Policy Of Peoples Rights In Around Mining Corporate Post-Mining Activities

Directory of Open Access Journals (Sweden)

Teng Berlianty

2015-08-01

Full Text Available This study aims to gain an understanding of the essence of the rights of communities around post-mining corporate responsibility towards the fulfillment of the rights of communities around post-mining as well as government policies to protect the sustainability of the post-mining communities around the mining business. This type of research is a normative legal research methods using primary legal materials secondary and tertiary. With the approach of sociolegal through down the field in Gebe to get data concrete. Data were analyzed with qualitative analysis. The results showed that the essence of the rights of communities around mining operations after the mine in the form of the right to a decent life welfare the right to social security in the form of employment the guarantee of free education and healthcare for the local population as well as the right to a good environment and healthy as a guarantee of the continuity of human existence and future generations. These rights have not been fully realized post-mining. Corporate responsibility in accordance with Article 74 of Law No. 40 of 2007 on the fulfillment of the rights of communities around mining operations after the mine in the form of welfare responsibilities clothing food and shelter especially electricity and water have not been met then the social responsibility to empower communities around the mine as stakeholders as well as environmental responsibility. Legal policy such as the empowerment of communities around the mine in order to be self-sufficient after the post-mining public service policies in education and health as a form of existence of government using existing programs nationally and subordinate to the PT. Antam. as well as environmental protection policies in the form of post-mining reclamation formulated in the companys liabilities.

Geochemical Characterization of Mine Waste, Mine Drainage, and Stream Sediments at the Pike Hill Copper Mine Superfund Site, Orange County, Vermont

Science.gov (United States)

Piatak, Nadine M.; Seal, Robert R.; Hammarstrom, Jane M.; Kiah, Richard G.; Deacon, Jeffrey R.; Adams, Monique; Anthony, Michael W.; Briggs, Paul H.; Jackson, John C.

2006-01-01

The Pike Hill Copper Mine Superfund Site in the Vermont copper belt consists of the abandoned Smith, Eureka, and Union mines, all of which exploited Besshi-type massive sulfide deposits. The site was listed on the U.S. Environmental Protection Agency (USEPA) National Priorities List in 2004 due to aquatic ecosystem impacts. This study was intended to be a precursor to a formal remedial investigation by the USEPA, and it focused on the characterization of mine waste, mine drainage, and stream sediments. A related study investigated the effects of the mine drainage on downstream surface waters. The potential for mine waste and drainage to have an adverse impact on aquatic ecosystems, on drinking- water supplies, and to human health was assessed on the basis of mineralogy, chemical concentrations, acid generation, and potential for metals to be leached from mine waste and soils. The results were compared to those from analyses of other Vermont copper belt Superfund sites, the Elizabeth Mine and Ely Copper Mine, to evaluate if the waste material at the Pike Hill Copper Mine was sufficiently similar to that of the other mine sites that USEPA can streamline the evaluation of remediation technologies. Mine-waste samples consisted of oxidized and unoxidized sulfidic ore and waste rock, and flotation-mill tailings. These samples contained as much as 16 weight percent sulfides that included chalcopyrite, pyrite, pyrrhotite, and sphalerite. During oxidation, sulfides weather and may release potentially toxic trace elements and may produce acid. In addition, soluble efflorescent sulfate salts were identified at the mines; during rain events, the dissolution of these salts contributes acid and metals to receiving waters. Mine waste contained concentrations of cadmium, copper, and iron that exceeded USEPA Preliminary Remediation Goals. The concentrations of selenium in mine waste were higher than the average composition of eastern United States soils. Most mine waste was

Mine drainage treatment

OpenAIRE

Golomeova, Mirjana; Zendelska, Afrodita; Krstev, Boris; Golomeov, Blagoj; Krstev, Aleksandar

2012-01-01

Water flowing from underground and surface mines and contains high concentrations of dissolved metals is called mine drainage. Mine drainage can be categorized into several basic types by their alkalinity or acidity. Sulfide rich and carbonate poor materials are expected to produce acidic drainage, and alkaline rich materials, even with significant sulfide concentrations, often produce net alkaline water. Mine drainages are dangerous because pollutants may decompose in the environment. In...

Mining dictionary: underground mining; open-cast mining; preparation and beneficiation; geology of mineral deposits

Energy Technology Data Exchange (ETDEWEB)

Goergen, H; Stoll, R D; Vriesen, R D; Welzenberg, B

1981-01-01

The dictionary reflects the latest technical developments in the vocabulary of mining methods and the mining industry. Volume I of the dictionary is English to German, Volume II German to English. 36,000 entries are included.

Mining Views : database views for data mining

NARCIS (Netherlands)

Blockeel, H.; Calders, T.; Fromont, É.; Goethals, B.; Prado, A.; Nijssen, S.; De Raedt, L.

2007-01-01

We propose a relational database model towards the integration of data mining into relational database systems, based on the so called virtual mining views. We show that several types of patterns and models over the data, such as itemsets, association rules, decision trees and clusterings, can be

Coastal mining

Science.gov (United States)

Bell, Peter M.

The Exclusive Economic Zone (EEZ) declared by President Reagan in March 1983 has met with a mixed response from those who would benefit from a guaranteed, 200-nautical-mile (370-km) protected underwater mining zone off the coasts of the United States and its possessions. On the one hand, the U.S. Department of the Interior is looking ahead and has been very successful in safeguarding important natural resources that will be needed in the coming decades. On the other hand, the mining industry is faced with a depressed metals and mining market.A report of the Exclusive Economic Zone Symposium held in November 1983 by the U.S. Geological Survey, the Mineral Management Service, and the Bureau of Mines described the mixed response as: “ … The Department of Interior … raring to go into promotion of deep-seal mining but industrial consortia being very pessimistic about the program, at least for the next 30 or so years.” (Chemical & Engineering News, February 5, 1983).

Rock burst prevention at steep seam mining

Energy Technology Data Exchange (ETDEWEB)

Efremov, G D

1988-09-01

At steep shield longwalls one method of preventing rock bursts is to avoid sharp angles during working. Stress in coal and rock body that appears when steep seams are worked where rock bursts occur at corners of set-up entries is discussed. The dynamic interaction between gas and rock pressure is assessed. Maintains that in order to avoid rock bursts at these places it is necessary to turn the protruding coal wall by 20-30 degrees towards the coal body to divert the action of shift forces. At the same time the face should also be inclined (by 10-15 degrees) to move the zones of increased stress away from the corner into the coal and rock body. Stress at workings with round cross-sections is 3-4 times lower than at square cross-sections. Recommendations are given that concern shearer loader operation (semi-spherical shape of the face), borehole drilling and water injection. Initial distance of 10-15 m between boreholes is suggested. 3 refs.

Specialized mining GIS system MineGIS SMZ Jelšava

Directory of Open Access Journals (Sweden)

Peter Sasvári

2005-12-01

Full Text Available Following, the real needs for new mining information system requested by SMZ Jelšava, the Department of Mineral Deposits and Applied Geology (KLaAG at the Technical University of Košice (TUKE has prepared a specification for the specialized mining geographic information system called MineGIS SMZ Jelšava. The main roles of the new system have been defined as follows of reserves: the administration, analyse and the visualization of all mining geo-data related to the estimation.

South African mine valuation

Energy Technology Data Exchange (ETDEWEB)

Storrar, C D

1977-01-01

This article sets out the basic concepts of mine valuation, with gold mining receiving more space than base minerals and coal. Sampling practice is given special attention. Chapter headings are methods of investigation, sampling, underground sampling, averaging of underground sampling, diamond-drill sampling, mass and mineral content of ore, organization of a sample office, working costs, mining pay limits, ore reserves, ore accounting, maintenance of grade, forecasting operations and life of mine, statistical mine valuation, state's share of profits and taxation, and financial valuation of mining ventures.

Microbes from mined sites: Harnessing their potential for reclamation of derelict mine sites

International Nuclear Information System (INIS)

Thavamani, Palanisami; Samkumar, R. Amos; Satheesh, Viswanathan; Subashchandrabose, Suresh R.; Ramadass, Kavitha; Naidu, Ravi; Venkateswarlu, Kadiyala; Megharaj, Mallavarapu

2017-01-01

Derelict mines pose potential risks to environmental health. Several factors such as soil structure, organic matter, and nutrient content are the greatly affected qualities in mined soils. Soil microbial communities are an important element for successful reclamation because of their major role in nutrient cycling, plant establishment, geochemical transformations, and soil formation. Yet, microorganisms generally remain an undervalued asset in mined sites. The microbial diversity in derelict mine sites consists of diverse species belonging to four key phyla: Proteobacteria, Acidobacteria, Firmicutes, and Bacteroidetes. The activity of plant symbiotic microorganisms including root-colonizing rhizobacteria and ectomycorrhizal fungi of existing vegetation in the mined sites is very high since most of these microbes are extremophiles. This review outlines the importance of microorganisms to soil health and the rehabilitation of derelict mines and how microbial activity and diversity can be exploited to better plan the soil rehabilitation. Besides highlighting the major breakthroughs in the application of microorganisms for mined site reclamation, we provide a critical view on plant−microbiome interactions to improve revegetation at the mined sites. Also, the need has been emphasized for deciphering the molecular mechanisms of adaptation and resistance of rhizosphere and non-rhizosphere microbes in abandoned mine sites, understanding their role in remediation, and subsequent harnessing of their potential to pave the way in future rehabilitation strategies for mined sites. - Highlights: • Abandoned mines pose potential risks to human and environmental health. • Re-establishment of a self-sustaining vegetative cover at derelict mines is a major challenge. • Soil microbial communities are very important for successful reclamation of mined sites. • Role of microorganisms in soil function in derelict mines needs to be understood.

Mining Views : database views for data mining

NARCIS (Netherlands)

Blockeel, H.; Calders, T.; Fromont, É.; Goethals, B.; Prado, A.

2008-01-01

We present a system towards the integration of data mining into relational databases. To this end, a relational database model is proposed, based on the so called virtual mining views. We show that several types of patterns and models over the data, such as itemsets, association rules and decision

High utility-itemset mining and privacy-preserving utility mining

Directory of Open Access Journals (Sweden)

Jerry Chun-Wei Lin

2016-03-01

Full Text Available In recent decades, high-utility itemset mining (HUIM has emerging a critical research topic since the quantity and profit factors are both concerned to mine the high-utility itemsets (HUIs. Generally, data mining is commonly used to discover interesting and useful knowledge from massive data. It may, however, lead to privacy threats if private or secure information (e.g., HUIs are published in the public place or misused. In this paper, we focus on the issues of HUIM and privacy-preserving utility mining (PPUM, and present two evolutionary algorithms to respectively mine HUIs and hide the sensitive high-utility itemsets in PPUM. Extensive experiments showed that the two proposed models for the applications of HUIM and PPUM can not only generate the high quality profitable itemsets according to the user-specified minimum utility threshold, but also enable the capability of privacy preserving for private or secure information (e.g., HUIs in real-word applications.

76 FR 54163 - Proximity Detection Systems for Continuous Mining Machines in Underground Coal Mines

Science.gov (United States)

2011-08-31

... Detection Systems for Continuous Mining Machines in Underground Coal Mines AGENCY: Mine Safety and Health... (except full-face continuous mining machines) with proximity detection systems. Miners working near..., each underground coal mine operator would be required to install proximity detection systems on...

Uranium mine ventilation

International Nuclear Information System (INIS)

Katam, K.; Sudarsono

1982-01-01

Uranium mine ventilation system aimed basically to control and decreasing the air radioactivity in mine caused by the radon emanating from uranium ore. The control and decreasing the air ''age'' in mine, with adding the air consumption volume, increasing the air rate consumption, closing the mine-out area; using closed drainage system. Air consumption should be 60m 3 /minute for each 9m 2 uranium ore surfaces with ventilation rate of 15m/minute. (author)

Appalachian mine soil morphology and properties: Effects of weathering and mining method

Energy Technology Data Exchange (ETDEWEB)

Haering, K.C.; Daniels, W.L.; Galbraith, J.M. [Virginia Polytechnic Institute & State University, Blacksburg, VA (United States)

2004-08-01

Surface coal mining and reclamation methods in the Appalachians have changed dramatically since the passage of the Surface Mining Control and Reclamation Act (SMCRA) of 1977 and subsequent improvements in mining and reclamation technology. In this study, 30 pre-SMCRA mine soil profiles (4-20 yr old) were examined and sampled in 1980 and compared with 20 mine soil profiles (8-13 yr old) described in the same area in 2002 after it had been completely remined by modern deep cut methods. Mine soils in both sampling years had high rock fragment content (42-81%), relatively well-developed A horizons, and generally exhibited A-C or A-AC-C horizonation. Although six Bw horizons were described in 1980, only two met all requirements for cambic horizons. The 1980 mine soils developed in overburden dominated by oxidized, preweathered material due to relatively shallow mining cuts. The 1980 mine soils had lower rock fragment content, finer textures, lower pH, and tended to be more heterogeneous in horizonation, morphology, and texture than soils observed in 2002, which had formed primarily in unweathered overburden from deeper cuts. Half the pedons sampled in both years had densic materials within 70 cm of the surface. Four poorly to very poorly drained soil profiles were described in each sampling year containing distinct hydric soil indicators in surface horizons. While older pre-SMCRA mine soils do have many properties in common with newer mine soils, their properties are highly influenced by the fact that they generally have formed in more weathered overburden from higher in the geologic column. Overall, Appalachian mine soils are much more complex in subsoil morphology than commonly assumed, and differential compaction greatly complicates their internal drainage and limits their overall productivity potential.

First Mining workshop of Mining and metallurgical of MERCOSUR

International Nuclear Information System (INIS)

1994-01-01

In the city of Montevideo, capital of the Oriental Republic of Uruguay, at 23 days of September 1994, under the First Meeting of Mercosur Mining Metallurgical, meet representatives of the mining sector in the countries signed the Treaty of Asuncion , attended as observers, authorities of the Republic of Bolivia and Ecuador and representatives of the productive labor, legislative and research. The primary objective is to integrate the mining sectors of those countries, taking into account the specificity of the mining, given by the resource it uses, the need for high-risk investment with slow recoveries of capital and infrastructure problems, taking into account leverage and its remarkable impact on the development of regional economies.

On 3D Geo-visualization of a Mine Surface Plant and Mine Roadway

Institute of Scientific and Technical Information of China (English)

WANG Yunjia; FU Yongming; FU Erjiang

2007-01-01

Constructing the 3D virtual scene of a coal mine is the objective requirement for modernizing and processing information on coal mining production. It is also the key technology to establish a "digital mine". By exploring current worldwide research, software and hardware tools and application demands, combined with the case study site (the Dazhuang mine of Pingdingshan coal group), an approach for 3D geo-visualization of a mine surface plant and mine roadway is deeply discussed. In this study, the rapid modeling method for a large range virtual scene based on Arc/Info and SiteBuilder3D is studied, and automatic generation of a 3D scene from a 2D scene is realized. Such an automatic method which can convert mine roadway systems from 2D to 3D is realized for the Dazhuang mine. Some relevant application questions are studied, including attribute query, coordinate query, distance measure, collision detection and the dynamic interaction between 2D and 3D virtual scenes in the virtual scene of a mine surface plant and mine roadway. A prototype system is designed and developed.

Survey of nine surface mines in North America. [Nine different mines in USA and Canada

Energy Technology Data Exchange (ETDEWEB)

Hayes, L.G.; Brackett, R.D.; Floyd, F.D.

1981-01-01

This report presents the information gathered by three mining engineers in a 1980 survey of nine surface mines in the United States and Canada. The mines visited included seven coal mines, one copper mine, and one tar sands mine selected as representative of present state of the art in open pit, strip, and terrace pit mining. The purpose of the survey was to investigate mining methods, equipment requirements, operating costs, reclamation procedures and costs, and other aspects of current surface mining practices in order to acquire basic data for a study comparing conventional and terrace pit mining methods, particularly in deeper overburdens. The survey was conducted as part of a project under DOE Contract No. DE-AC01-79ET10023 titled The Development of Optimal Terrace Pit Coal Mining Systems.

Mining planing introduction

International Nuclear Information System (INIS)

Toledo, R.D.

1985-01-01

Basic concepts concerning mining parameters, plan establishment and typical procedure methods applied throughout the physical execution of mining operations are here determined, analyzed and discussed. Technological and economic aspects of the exploration phase are presented as well as general mathematical and statistical methods for estimating, analyzing and representing mineral deposits which are virtually essential for good mining project execution. The characterization of important mineral substances and the basic parameters of mining works are emphasized in conjunction with long, medium and short term mining planning. Finally, geological modelling, ore reserves calculations and final economic evaluations are considered using a hypothetical example in order to consolidate the main elaborated ideas. (D.J.M.) [pt

African mining '91

International Nuclear Information System (INIS)

1991-01-01

The second 'African Mining' conference was held in June 1991, and followed the first event held in May 1987. That full four-year period was characterized by substantial changes in the political and economic climate of many countries in both hemispheres. The results of many of these changing facets of our industry are described in the papers in African Mining'91. Many of the papers deal with advances in technology, which is the main reason for the meeting. There are 37 papers under the headings general, mining, metallurgy and geology and exploration. Most papers are concerned with gold, copper and mineral mining. One paper concerning uranium mining operations in Namibia is indexed separately. (author)

The remediation of abandoned workings of a mining area in Ningxiang uranium mine

International Nuclear Information System (INIS)

Liu Yaochi; Zhou Xinghuo; Liu Bing

2004-01-01

The typical mining under buildings and river was used in a mining area of Ningxiang uranium mine. After the mining ended, 32.1% of the 2.68 m 3 abandoned workings did not fill because of limitation of the cut-and-fill mining method at that time. To remedy this, the mine used new filling methods. After the remedial action, the filling coefficient of pits reached 100%, and that of tunnels reached 86%. It can be proved by the monitoring data that the subsiding of surface has been effectively controlled at the abandoned workings

The levels of disclosure relating to mine closure obligations by platinum mining companies

Directory of Open Access Journals (Sweden)

Joline Sturdy

2017-06-01

Aim: The aim of this study is to establish the extent to which platinum mines listed on the Johannesburg Stock Exchange (JSE comply with a recommended disclosure framework. Setting: South Africa is the largest producer of platinum in the world. The study covers all platinum mines listed on the JSE. Methods: Using a framework, a census of the annual financial statements, integrated annual reports and sustainability reports or websites was conducted to determine the level of compliance of disclosure relating to mine closure obligations to the recommended disclosure framework. Results: The results show disclosure relating to mine closure obligations of platinum mines listed on the JSE is inconsistent and not sufficient for stakeholders to understand the scope, key assumptions, parameters or reliability of the assessment and calculation of mine closure obligations. Conclusion: The assumptions used to determine mine closure obligations are specialised and multi-disciplinary. The accuracy and reliability of mine closure obligations will improve dramatically through greater transparency and access to information. It is recommended that the JSE listings for mining companies should require a competent person’s report to provide disclosure on assumptions, key values and processes applied to determine the mine closure obligations. Furthermore, it is recommended that the Department of Mineral Resources implements a mechanism of independent assessment of mine closure obligations by experts on an ongoing basis.

Economics of mine water treatment

OpenAIRE

Dvořáček, Jaroslav; Vidlář, Jiří; Štěrba, Jiří; Heviánková, Silvie; Vaněk, Michal; Barták, Pavel

2012-01-01

Mine water poses a significant problem in lignite coal mining. The drainage of mine water is the fundamental prerequisite of mining operations. Under the legislation of the Czech Republic, mine water that discharges into surface watercourse is subject to the permission of the state administration body in the water management sector. The permission also stipulates the limits for mine water pollution. Therefore, mine water has to be purified prior to discharge. Although all...

Mine waste management

International Nuclear Information System (INIS)

Hutchinson, I.P.G.; Ellison, R.D.

1992-01-01

This book reports on mine waste management. Topics covered include: Performance review of modern mine waste management units; Mine waste management requirements; Prediction of acid generation potential; Attenuation of chemical constituents; Climatic considerations; Liner system design; Closure requirements; Heap leaching; Ground water monitoring; and Economic impact evaluation

Post-mining in France

International Nuclear Information System (INIS)

2007-01-01

This plentifully illustrated book aims at showing how new equilibria are building up during the transition between mining activity and post-mining, and at stressing on the necessity to keep up the cultural elements, the competencies and knowledge of mining works. The first chapter - mine and men - shows the importance of mineral substances in the objects of the everyday life, illustrates the importance of the mining tradition in France and describes the technical and administrative organisation of the end of the mining activity (works, rehabilitation, regulation, monitoring..). Chapter two - exploitation methods - presents the surface and underground facilities and their impact on the environment (extraction machines, workshops, ore processing plants, decantation ponds..). The third chapter deals with the rehabilitation and monitoring aspects: impact of mining activity stoppage on underground and surface waters, land stability, soils cleansing.. The last chapter summarizes the history of French mining region by region: Nord-Pas-de-Calais, Lorraine-Alsace, Massif central, Bretagne-Normandie, Provence-Alpes-Cote d'Azur and Pyrenees

Treating mine water

Energy Technology Data Exchange (ETDEWEB)

Matlak, E S; Kochegarova, L V; Zaslavskaya, I Yu

1980-10-01

Taking into account the negative influence of mine waters with suspended matter on the natural environment on the surface, the maximum treatment of mine water underground, is proposed. It is noted that full treatment of mine water, using conventional filtration methods, would be rather expensive, but a limited treatment of mine water is possible. Such treated mine water can be used in dust suppression and fire fighting systems. Mine water treated underground should be free of any odor, with pH level ranging from 6 to 9.5, with suspended matter content not exceeding 50 mg/l and coli-titre not less than 300 cm$SUP$3. It is suggested that water treatment to produce water characterized by these parameters is possible and economical. Recommendations on construction of underground sedimentation tanks and channels, and a hydraulic system of cleaning sedimentation tanks are proposed. The settling would be stored underground in abandoned workings. (2 refs.) (In Russian)

MONITORING METAL POLLUTION LEVELS IN MINE WASTES AROUND A COAL MINE SITE USING GIS

Directory of Open Access Journals (Sweden)

D. Sanliyuksel Yucel

2017-11-01

Full Text Available In this case study, metal pollution levels in mine wastes at a coal mine site in Etili coal mine (Can coal basin, NW Turkey are evaluated using geographical information system (GIS tools. Etili coal mine was operated since the 1980s as an open pit. Acid mine drainage is the main environmental problem around the coal mine. The main environmental contamination source is mine wastes stored around the mine site. Mine wastes were dumped over an extensive area along the riverbeds, and are now abandoned. Mine waste samples were homogenously taken at 10 locations within the sampling area of 102.33 ha. The paste pH and electrical conductivity values of mine wastes ranged from 2.87 to 4.17 and 432 to 2430 μS/cm, respectively. Maximum Al, Fe, Mn, Pb, Zn and Ni concentrations of wastes were measured as 109300, 70600, 309.86, 115.2, 38 and 5.3 mg/kg, respectively. The Al, Fe and Pb concentrations of mine wastes are higher than world surface rock average values. The geochemical analysis results from the study area were presented in the form of maps. The GIS based environmental database will serve as a reference study for our future work.

Monitoring Metal Pollution Levels in Mine Wastes around a Coal Mine Site Using GIS

Science.gov (United States)

Sanliyuksel Yucel, D.; Yucel, M. A.; Ileri, B.

2017-11-01

In this case study, metal pollution levels in mine wastes at a coal mine site in Etili coal mine (Can coal basin, NW Turkey) are evaluated using geographical information system (GIS) tools. Etili coal mine was operated since the 1980s as an open pit. Acid mine drainage is the main environmental problem around the coal mine. The main environmental contamination source is mine wastes stored around the mine site. Mine wastes were dumped over an extensive area along the riverbeds, and are now abandoned. Mine waste samples were homogenously taken at 10 locations within the sampling area of 102.33 ha. The paste pH and electrical conductivity values of mine wastes ranged from 2.87 to 4.17 and 432 to 2430 μS/cm, respectively. Maximum Al, Fe, Mn, Pb, Zn and Ni concentrations of wastes were measured as 109300, 70600, 309.86, 115.2, 38 and 5.3 mg/kg, respectively. The Al, Fe and Pb concentrations of mine wastes are higher than world surface rock average values. The geochemical analysis results from the study area were presented in the form of maps. The GIS based environmental database will serve as a reference study for our future work.

Reformulating the calculation of mining privileges for medium and large mining

Directory of Open Access Journals (Sweden)

Pedro Franco Concha

2016-01-01

Full Text Available Throughout this paper those technical and accounting concepts of the Law of mining privileges that generate ambiguity and incongruity for businesses has been analyzed and identified. For this reason, we have developed a proposal amending the calculation of mining privileges based on two main aspects: (i terminology used in the law and (ii establishment of income before retribution to stakholders and taxes as a basis for calculating privileges. As a result, it was established as an object of study for all mining companies paying privileges; however, for purposes of the investigation three representative mining companies of medium and large mining were selected. Later interviews were arranged with financial and tax managers of the companies mentioned above as well as experts in the field of mining privileges; it was concluded that the concepts of "cost" and "corresponding fiscal year" mentioned in the Law generated ambiguities, inconsistencies and accounting distortions. Also, mining companies and experts agreed that the current basis for the calculation of the privileges is not adequate for the mining sector since it does not reflect the financial situation of companies. Therefore, a proposal for reformulation of the applied priviously and a new basis for calculating the mining privileges based on the cost of sales is made; since, in the cost of sales is found what Kieso and Weygandt (1999 denominated as "the price paid for the right to seek and find a hidden Natural resources, or paid by a source already discovered"

Underground coal mine air quality in mines using disposable diesel exhaust filter control devices

Energy Technology Data Exchange (ETDEWEB)

Carlson, D.H.; Johnson, J.H.; Bagley, S.T.; Gratz, L.D. [Michigan Technological University, Houghton, MI (United States). Dept. of Mining Engineering

1996-07-01

As part of a collaborative study with the US Bureau of Mines, in-mine studies have been conducted to assess the effects of a low temperature disposable diesel exhaust filter. The mines have been designed as mines R and S in US Bureau of Mines publications. Each mine operated three to four Jeffrey 4110 ramcar haulage vehicles in the test section. The ramcars were equipped with MWM D916-6 diesel engines, rated at 74.6 kW (100 hp), and were operated for 3 days with the disposal diesel exhaust filter and 2 days without in both mines. Average diesel particulate matter control efficiencies, as measured by samplers located on the coal haulage vehicle, were 80% in mine R and 76% in mine S. Diesel particulate matter average control efficiencies, as measured in the diesel engine tailpipe, were 52% for mine R (for two ramcar vehicles) and 86% for mine S (for four ramcar vehicles). The air quality index control efficiencies, as measured by samplers located on the coal haulage vehicle were 48% in mine R and 51% in mine S. The exhaust quality index control efficiencies from tailpipe measurements were 45% for mine R and 63% for mine S. As measured by a high volume sampler in mine S, diesel particulate matter and associated organics and mutagenic activity were reduced approximately 50% with the use of the disposal diesel exhaust filter. Similar results were found with modified personal samplers in mine R. Little effect was found on relative removal of semivolatile organics. The disposal diesel exhaust filter resulted in about a 50% reduction in the most volatile polynuclear hydrocarbons; however, there appeared to be little effect on the less volatile polynuclear hydrocarbons. The disposable diesel exhaust filter appears to be very effective in reducing the levels of all the diesel exhaust particulate components, while having minor effects on the relative breakdown of the individual components of the particulate. 30 refs., 13 figs., 4 tabs.

Colombian mining legislation

International Nuclear Information System (INIS)

Mendoza Delgado, Eva Isolina

2004-01-01

The paper makes a historical recount of the mining legislation in Colombia, it is about the more relevant aspects of the Code of Mines, like they are the title miner, obligations, economic aspects, integration of mining areas and of the benefits contemplated in the law 685 of 2001

Partnership in mining

Energy Technology Data Exchange (ETDEWEB)

Haslam, R

1988-04-01

This paper discusses the benefits resulting from mutual cooperation and information exchange between the UK and USA coal industries. The aim of this cooperation is to promote safe and efficient extraction and profitable use of coal. Advanced mining technologies and mechanisation of the coal mines are some of the results of research cooperation between British Coal and the US Bureau of Mines. In addition, Britain has studied and put into good use the management styles, working practices and pay structure, and mining engineering adopted in the USA.

Radioecological challenges for mining

Energy Technology Data Exchange (ETDEWEB)

Vesterbacka, P.; Ikaeheimonen, T.K.; Solatie, D. [Radiation and Nuclear Safety Authority (Finland)

2014-07-01

In Finland, mining became popular in the mid-1990's when the mining amendments to the law made the mining activities easier for foreign companies. Also the price of the minerals rose and mining in Finland became economically profitable. Expanding mining industry brought new challenges to radiation safety aspect since radioactive substances occur in nearly all minerals. In Finnish soil and bedrock the average crystal abundance of uranium and thorium are 2.8 ppm and 10 ppm, respectively. It cannot be predicted beforehand how radionuclides behave in the mining processes which why they need to be taken into account in mining activities. Radiation and Nuclear Safety Authority (STUK) has given a national guide ST 12.1 based on the Finnish Radiation Act. The guide sets the limits for radiation doses to the public also from mining activities. In general, no measures to limit the radiation exposure are needed, if the dose from the operation liable to cause exposure to natural radiation is no greater than 0.1 mSv per year above the natural background radiation dose. If the exposure of the public may be higher than 0.1 mSv per year, the responsible party must provide STUK a plan describing the measures by which the radiation exposure is to be kept as low as is reasonably achievable. In that case the mining company responsible company has to make a radiological baseline study. The baseline study must focus on the environment that the mining activities may impact. The study describes the occurrence of natural radioactivity in the environment before any mining activities are started. The baseline study lasts usually for two to three years in natural circumstances. Based on the baseline study measurements, detailed information of the existing levels of radioactivity in the environment can be attained. Once the mining activities begin, it is important that the limits are set for the wastewater discharges to the environment and environmental surveillance in the vicinity of

Imouraren mining exploitation : Complementary studies Synthetic report Volum B - Mines

International Nuclear Information System (INIS)

1980-01-01

The object of the current study is to determine the main technical characteristics of the reference project of a mine that can supply the necessary ore quantity at a production of 3000 tonnes uranium per year, along 10 years. The project is one of the possible solutions for exploiting the mine. The current study permits to establish : investment and functioning cost estimation, overall project of the mining exploitation program, necessary strength estimation, average ore grades evaluation and variations of these grades, utilities needs, production vizing program, main exploitation methods and necessary materials. Reference project study of the mine serves as base to the economics studies and studies optimization [fr

Modeling of Energy-saving System of Conditioning Mine Air for Shallow Underground Mines

Science.gov (United States)

Nikolaev, Alexandr; Miftakhov, Timur; Nikolaeva, Evgeniya

2017-11-01

Mines of Verkhnekamsk potassium-magnesium salt deposit in Perm Krai can be subsumed under shallow mines (depth less than 500 meters). At the present moment in shallow underground mines the are problem of condensate formation in large quantities, when ventilation warm seasons of the year. This problem is more actual for salt mine, where during contact between water and potassium-magnesium ore produced electrolyte, which give rise wear of equipment. For prevent/quantity reduction condensate formation in mine used system of conditioning (refrigerating and dehumidifying) mine air (ACS). However, application this system is limited by reason of tremendous costs of electric energy for their work.

WEB STRUCTURE MINING

Directory of Open Access Journals (Sweden)

CLAUDIA ELENA DINUCĂ

2011-01-01

Full Text Available The World Wide Web became one of the most valuable resources for information retrievals and knowledge discoveries due to the permanent increasing of the amount of data available online. Taking into consideration the web dimension, the users get easily lost in the web’s rich hyper structure. Application of data mining methods is the right solution for knowledge discovery on the Web. The knowledge extracted from the Web can be used to raise the performances for Web information retrievals, question answering and Web based data warehousing. In this paper, I provide an introduction of Web mining categories and I focus on one of these categories: the Web structure mining. Web structure mining, one of three categories of web mining for data, is a tool used to identify the relationship between Web pages linked by information or direct link connection. It offers information about how different pages are linked together to form this huge web. Web Structure Mining finds hidden basic structures and uses hyperlinks for more web applications such as web search.

The South African mining industry

International Nuclear Information System (INIS)

Langton, G.

1982-01-01

This paper covers six of the many mining and associated developments in South Africa. These are: (1) Deep level gold mining at Western Deep Levels Limited - (2) Palabora Mining Company Limited - SA's unique copper mine - (3) Production of steel and vanadium-rich slag at Highveld Steel and Vanadium Corporation - (4) Coal mining at Kriel and Kleinkopje Collieries - (5) A mass mining system for use below the Gabbro Sill at Premier Diamond Mine - (6) Uranium production - joint metallurgical scheme- Orange Free State Gold Mines. - For publication in this journal the original paper has been summarised. Should any reader wish to have the full text in English he should write to the author at the address below. (orig.) [de

Mountaintop mining consequences

Science.gov (United States)

M.A. Palmer; E.S. Bernhardt; W.H. Schlesinger; K.N. Eshleman; E. Foufoula-Georgiou; M.S. Hendryx; A.D. Lemly; G.E. Likens; O.L. Loucks; M.E. Power; P.S. White; P.R. Wilcock

2010-01-01

There has been a global, 30-year increase in surface mining (1), which is now the dominant driver of land-use change in the central Appalachian ecoregion of the United States (2). One major form of such mining, mountaintop mining with valley fills (MTM/VF) (3), is widespread throughout eastern Kentucky, West Virginia (WV), and southwestern Virginia. Upper elevation...

Improving safety in mining

Energy Technology Data Exchange (ETDEWEB)

NONE

2007-08-15

AcuMine is a spin-out company from CRC Mining Australia and the University of Sydney's Australian Centre for Field Robotics (ACFR). Its focus is to provide safety and fatigue management in mining environments. The AcuLine Haul Check system was its first development. Of greater benefit to safety in mines will be the AcuMine Proximity System (APPS) developed to reliably detect and warn drivers when in proximity to other trucks and utility vehicles and to detect personnel near to those heavy vehicles. 6 figs.

Remote control of safety and technological mining processes in underground coal mines

Energy Technology Data Exchange (ETDEWEB)

Marjanovic, D. (Elektronska Industrija RO IRI OOUR Razvoj, Nis (Yugoslavia))

1989-02-01

Discusses importance of data relevant to remote monitoring of production and safety at work in underground coal mines. The EI PS 2000 multi-purpose system developed by Elektronska Industrija, Nis, for use with AP-X1 and AP-X2 microcomputers in Serbian mines is described. Component parts include the CUM-8 central unit, the CIP-8 communication interface processor, the SNM-64 disjunction unit, the NM-64 energy supply unit and the CRT alarm monitor. This system is designed to warn of mine fires, methane and coal dust explosions, to help in evacuating mine crews, to control production processes and mine management and other functions. 8 refs

The mine planning process for an open-pit diamond mining operation - a case study on Letseng diamond mine in Lesotho

OpenAIRE

Madowe, A.

2013-01-01

This paper discusses the mine planning process for Letseng diamond mine in the Kingdom of Lesotho, in conjunction with the various software packages used during the process. The major pillars of the long-term mine planning process at Letseng are pit optimization followed by pit design and scheduling. Letseng uses Gemcom Whittle and GEMS for pit optimization and design and Runge XPAC for scheduling. The output of the mine planning process results in the generation of published mineral reserves...

A Review of Mine Rescue Ensembles for Underground Coal Mining in the United States.

Science.gov (United States)

Kilinc, F Selcen; Monaghan, William D; Powell, Jeffrey B

The mining industry is among the top ten industries nationwide with high occupational injury and fatality rates, and mine rescue response may be considered one of the most hazardous activities in mining operations. In the aftermath of an underground mine fire, explosion or water inundation, specially equipped and trained teams have been sent underground to fight fires, rescue entrapped miners, test atmospheric conditions, investigate the causes of the disaster, or recover the dead. Special personal protective ensembles are used by the team members to improve the protection of rescuers against the hazards of mine rescue and recovery. Personal protective ensembles used by mine rescue teams consist of helmet, cap lamp, hood, gloves, protective clothing, boots, kneepads, facemask, breathing apparatus, belt, and suspenders. While improved technology such as wireless warning and communication systems, lifeline pulleys, and lighted vests have been developed for mine rescuers over the last 100 years, recent research in this area of personal protective ensembles has been minimal due to the trending of reduced exposure of rescue workers. In recent years, the exposure of mine rescue teams to hazardous situations has been changing. However, it is vital that members of the teams have the capability and proper protection to immediately respond to a wide range of hazardous situations. Currently, there are no minimum requirements, best practice documents, or nationally recognized consensus standards for protective clothing used by mine rescue teams in the United States (U.S.). The following review provides a summary of potential issues that can be addressed by rescue teams and industry to improve potential exposures to rescue team members should a disaster situation occur. However, the continued trending in the mining industry toward non-exposure to potential hazards for rescue workers should continue to be the primary goal. To assist in continuing this trend, the mining industry

Atmospheric particulate matter size distribution and concentration in West Virginia coal mining and non-mining areas.

Science.gov (United States)

Kurth, Laura M; McCawley, Michael; Hendryx, Michael; Lusk, Stephanie

2014-07-01

People who live in Appalachian areas where coal mining is prominent have increased health problems compared with people in non-mining areas of Appalachia. Coal mines and related mining activities result in the production of atmospheric particulate matter (PM) that is associated with human health effects. There is a gap in research regarding particle size concentration and distribution to determine respiratory dose around coal mining and non-mining areas. Mass- and number-based size distributions were determined with an Aerodynamic Particle Size and Scanning Mobility Particle Sizer to calculate lung deposition around mining and non-mining areas of West Virginia. Particle number concentrations and deposited lung dose were significantly greater around mining areas compared with non-mining areas, demonstrating elevated risks to humans. The greater dose was correlated with elevated disease rates in the West Virginia mining areas. Number concentrations in the mining areas were comparable to a previously documented urban area where number concentration was associated with respiratory and cardiovascular disease.

Solution mining economics

International Nuclear Information System (INIS)

Hunkin, G.G.

1980-01-01

The field of application of in-situ solution mining of uranium is described and areas of competition with open pit and underground mining identified. The influence of high interest rates and dollar inflation on present values and rate of return is shown to be minimized by low capitalization and short construction lead times typical of in-situ leaching ventures. A scheme of three major project account divisions is presented and basic parameters necessary for mine planning are listed. 1979 cost ranges and useful methods of estimation of capital and operating costs are given for the in-situ uranium mining method

Mining face equipment

Energy Technology Data Exchange (ETDEWEB)

G, Litvinskiy G; Babyuk, G V; Yakovenko, V A

1981-01-07

Mining face equipment includes drilling advance wells, drilling using explosives on the contour bore holes, loading and transporting the crushed mass, drilling reinforcement shafts, injecting reinforcement compounds and moving the timber. Camouflet explosives are used to form relaxed rock stress beyond the mining area to decrease costs of reinforcing the mining area by using nonstressed rock in the advance well as support. The strengthening solution is injected through advanced cementing wells before drilling the contour bores as well as through radial cementing wells beyond the timbers following loading and transport of the mining debris. The advance well is 50-80 m.

OCHRE PRECIPITATES AND ACID MINE DRAINAGE IN A MINE ENVIRONMENT

Directory of Open Access Journals (Sweden)

BRANISLAV MÁŠA

2012-03-01

Full Text Available This paper is focused to characterize the ochre precipitates and the mine water effluents of some old mine adits and settling pits after mining of polymetallic ores in Slovakia. It was shown that the mine water effluents from two different types of deposits (adits; settling pits have similar composition and represent slightly acidic sulphate water (pH in range 5.60-6.05, sulphate concentration from 1160 to 1905 g.dm-3. The ochreous precipitates were characterized by methods of X-ray diffraction analysis (XRD, scanning electron microscopy (SEM and B.E.T. method for measuring the specific surface area and porosity. The dominant phases were ferrihydrite with goethite or goethite with lepidocrocide.

Data mining in radiology

International Nuclear Information System (INIS)

Kharat, Amit T; Singh, Amarjit; Kulkarni, Vilas M; Shah, Digish

2014-01-01

Data mining facilitates the study of radiology data in various dimensions. It converts large patient image and text datasets into useful information that helps in improving patient care and provides informative reports. Data mining technology analyzes data within the Radiology Information System and Hospital Information System using specialized software which assesses relationships and agreement in available information. By using similar data analysis tools, radiologists can make informed decisions and predict the future outcome of a particular imaging finding. Data, information and knowledge are the components of data mining. Classes, Clusters, Associations, Sequential patterns, Classification, Prediction and Decision tree are the various types of data mining. Data mining has the potential to make delivery of health care affordable and ensure that the best imaging practices are followed. It is a tool for academic research. Data mining is considered to be ethically neutral, however concerns regarding privacy and legality exists which need to be addressed to ensure success of data mining

Coal mine site reclamation

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-02-15

Coal mine sites can have significant effects on local environments. In addition to the physical disruption of land forms and ecosystems, mining can also leave behind a legacy of secondary detrimental effects due to leaching of acid and trace elements from discarded materials. This report looks at the remediation of both deep mine and opencast mine sites, covering reclamation methods, back-filling issues, drainage and restoration. Examples of national variations in the applicable legislation and in the definition of rehabilitation are compared. Ultimately, mine site rehabilitation should return sites to conditions where land forms, soils, hydrology, and flora and fauna are self-sustaining and compatible with surrounding land uses. Case studies are given to show what can be achieved and how some landscapes can actually be improved as a result of mining activity.

Swedish mines. Underground exploitation methods

International Nuclear Information System (INIS)

Paucard, A.

1960-01-01

Between 1949 and 1957, 10 engineers of the Mining research and exploitation department of the CEA visited 17 Swedish mines during 5 field trips. This paper presents a compilation of the information gathered during these field trips concerning the different underground mining techniques used in Swedish iron mines: mining with backfilling (Central Sweden and Boliden mines); mining without backfilling (mines of the polar circle area). The following techniques are described successively: pillar drawing and backfilled slices (Ammeberg, Falun, Garpenberg, Boliden group), sub-level pillar drawing (Grangesberg, Bloettberget, Haeksberg), empty room and sub-level pillar drawing (Bodas, Haksberg, Stripa, Bastkarn), storage chamber pillar drawing (Bodas, Haeksberg, Bastkarn), and pillar drawing by block caving (ldkerberget). Reprint of a paper published in Revue de l'Industrie Minerale, vol. 41, no. 12, 1959 [fr

Sustainable mining management

International Nuclear Information System (INIS)

Tejera Oliver, J. L.

2009-01-01

Mining activities are carried out by the older man and have provided resources, since ancient times, for their development and progress. With the discovery of fire will show the first metals that have marked the civilizations of copper, bronze and iron, and is the prehistory of the Stone Age tools that man has made from the exploitation of quarries first. The industrial revolution of the nineteenth century is linked to coal and steel, and could not conceiver of todays society without oil and gas, without silicon and coltan. But the mines are often aggressive and, despite their need and what they contribute to the development are answered by the societies where are made. during recent years there has been growing international efforts to try to make the minimum requirements of sustainable exploitation (European Directives, GMI, GRI, etc.) In AENOR, and within the Technical Committee of Standardization 22 Mining and Explosives, chaired by AITEMIN, was established the subcommittee 3, chaired by IGME, where, with the participation of all stake holders, have developed some standards on sustainable mining management sustainable mining that will be a tool available to mining companies to demonstrate their sustainable use to Society. (Author)

Synthesis report about the after-mine mission; Rapport de synthese sur la mission apres-mine

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The French ministry of economy finances and industry has assigned the mission of evaluating the after-mine management system to the general inspection of finances and the general council of mines. The after-mine management system encompasses all procedures of coal, iron and potash mines closing down, land reclamation and environmental remedial action and site rehabilitation. This document makes first a status of the problems generated by the stoppage of mining activities: technical aspects, costs, institutional, organisational and juridical aspects, conservation of competences, international benchmarking elements and good practices implemented in foreign countries. Then, in a second part, this report presents the recommendations of the after-mine mission about the mastery of after-mine costs in agreement with the respect of the technical and social goals, with the development of the after-mine institutional system with the scheduled disappearance of Charbonnages de France and Mines de Potasses d'Alsace companies, and with the conservation of competences in the framework of the post-mine operational structure proposed by the mission. (J.S.)

Synthesis report about the after-mine mission; Rapport de synthese sur la mission apres-mine

Energy Technology Data Exchange (ETDEWEB)

NONE

2003-07-01

The French ministry of economy finances and industry has assigned the mission of evaluating the after-mine management system to the general inspection of finances and the general council of mines. The after-mine management system encompasses all procedures of coal, iron and potash mines closing down, land reclamation and environmental remedial action and site rehabilitation. This document makes first a status of the problems generated by the stoppage of mining activities: technical aspects, costs, institutional, organisational and juridical aspects, conservation of competences, international benchmarking elements and good practices implemented in foreign countries. Then, in a second part, this report presents the recommendations of the after-mine mission about the mastery of after-mine costs in agreement with the respect of the technical and social goals, with the development of the after-mine institutional system with the scheduled disappearance of Charbonnages de France and Mines de Potasses d'Alsace companies, and with the conservation of competences in the framework of the post-mine operational structure proposed by the mission. (J.S.)

Exploration and Mining Roadmap

Energy Technology Data Exchange (ETDEWEB)

none,

2002-09-01

This Exploration and Mining Technology Roadmap represents the third roadmap for the Mining Industry of the Future. It is based upon the results of the Exploration and Mining Roadmap Workshop held May 10 ñ 11, 2001.

Coal Mine Permit Boundaries

Data.gov (United States)

Earth Data Analysis Center, University of New Mexico — ESRI ArcView shapefile depicting New Mexico coal mines permitted under the Surface Mining Control and Reclamation Act of 1977 (SMCRA), by either the NM Mining these...

Mining technology and policy issues 1983

International Nuclear Information System (INIS)

Anon.

1983-01-01

This book presents conference papers on advances in mineral processing, coal mining, communications for mining executives, environmental laws and regulations, exploration philosophy, exploration technology, government controls and the environment, management, mine finance, minerals availability, mine safety, occupational health, open pit mining, the precious metals outlook, public lands, system improvements in processing ores, and underground mining. Topics considered include coal pipelines and saline water, an incentive program for coal mines, sandwich belt high-angle conveyors, the development of a mining company, regulations for radionuclides, contracts for western coal production for Pacific Rim exports, and the control of radon daughters in underground mines

Exploration and mining - Report 800C. Predevelopment studies for mine methane management and utilization

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

Since 1999 Japan and Australia have been engaged in a 5-year predevelopment study of mine methane management and utilization. The effort aims to develop a technique to recover and utilize the greenhouse gas that escapes during coal mining for a decrease in the environmental impact of coal mining and to develop a technique to simulate the behavior of gas during coal mining. Understanding gas behavior will be useful in formulating a plan for optimum mine methane management and utilization in a newly developed mining zone. Technology transfer and interchangeability were considered and the Hunter Valley, New South Wales, was chosen as the experiment site. Tasks to discharge in fiscal 2000 were (1) collection of data on resources, technology, and the trend of Government policy and regulations, (2) measurement of stress and gas permeability and the assessment of mechanical strength of rock and coal at specified spots in the mining zone, (3) 3-dimensional gasping of the Wambo coal mine geography from the standpoints of geology and civil engineering, grasping of gas characteristics, and modelling and (4) the development of gas and rock behavior grasping technology for use during coal mining. (NEDO)

Mine shaft fire and smoke protection systems - an update on hardware development and in-mine testing

International Nuclear Information System (INIS)

Johnson, G.A.

1982-01-01

In 1976, The Bureau of Mines developed a prototype system to sense and extinguish fires in shafts and shaft stations in underground metal and nonmetal mines. Subsequent work modified this technology to include fueling areas, spontaneous combustion zones and coal mines. This paper updates IC-8783 ''In-mine Fire Tests of Mine Shaft Fire and Smoke Protection Systems'', which was published in 1978 and summarized the design and in-mine, actual fire testing of the first prototype mine shaft fire and smoke protection system. This paper also updates related work from IC-8775 ''Spontaneous Oxidation and Combustion of Sulfide Ores in Underground Mines, (also published in 1978) and IC-8808 ''In-mine Evaluation of Underground Fire and Smoke Detectors'', (published in early 1979)

Section of Cybernetics in Mining of Mining Committee of Polish Academy of Sciences - Pro Memoria

Science.gov (United States)

Wojaczek, Antoni; Miśkiewicz, Kazimierz

2017-09-01

Section of Cybernetics in Mining of Mining Committee of Polish Academy of Science (PAN) has been created by PAN Mining Committee in 1969. It was a section in Mining Committee of PAN, whose operation range included widely understood issues of automation, telecommunication and informatics in mining industry. The main operation method of the Section was to organize the periodic conferences dedicated to issues of control systems in mining. The first conference took place in 1971 in Katowice. Together with new (the current one) term of office of Mining Committee of PAN this Section ceased to exist. The paper presents (pro memoria) over 40 year long conference output of this Section that functioned within the scope of operation of Mining Committee of PAN up to 12th January 2016.

Potential for mine water reuse in an abandoned coal mine in northern Spain

Energy Technology Data Exchange (ETDEWEB)

Marques, A.; Garcia-Ordiales, E.; Loredo, J. [Oviedo Univ., Asturias (Spain)

2010-07-01

This paper investigated the potential re-utilization of mine water in industrial activities. Mine water characterization studies were conducted to evaluate mine waters from the abandoned La Camocha Mine in northwestern Spain. Hydrochemical studies have indicated that the water is bicarbonated with a low sulphate and iron content, and a neutral pH. The concentrations of trace metals are below water legislation for human consumption levels. The water can economically be transported for use in the irrigation of a botanical garden and sports centre located in the same region as the mine. Use of the water will help to preserve rivers and other waterways in the region, and may also minimize the environmental impacts of pumping activities at the mine. Fluid properties for various water samples were provided. 6 refs., 1 tab., 3 figs.

Uranium mining in Australia

International Nuclear Information System (INIS)

Anon.

1984-01-01

The mining of uranium in Australia is criticised in relation to it's environmental impact, economics and effects on mine workers and Aborigines. A brief report is given on each of the operating and proposed uranium mines in Australia

Spatio-Temporal Rule Mining

DEFF Research Database (Denmark)

Gidofalvi, Gyozo; Pedersen, Torben Bach

2005-01-01

Recent advances in communication and information technology, such as the increasing accuracy of GPS technology and the miniaturization of wireless communication devices pave the road for Location-Based Services (LBS). To achieve high quality for such services, spatio-temporal data mining techniques...... are needed. In this paper, we describe experiences with spatio-temporal rule mining in a Danish data mining company. First, a number of real world spatio-temporal data sets are described, leading to a taxonomy of spatio-temporal data. Second, the paper describes a general methodology that transforms...... the spatio-temporal rule mining task to the traditional market basket analysis task and applies it to the described data sets, enabling traditional association rule mining methods to discover spatio-temporal rules for LBS. Finally, unique issues in spatio-temporal rule mining are identified and discussed....

Mining Foreman School in Dabrowa Gornicza - heir to the Higher Mining School in Kielce

Energy Technology Data Exchange (ETDEWEB)

Ciuk, E

1988-02-01

The first Polish Higher Mining School was founded in 1816 in Kielce. The historical background of its foundation is described, curricula are outlined, prominent professors and graduates named. The significance of this School for Polish geology, mining and metallurgy to the present day is stressed. The School was closed in 1826 and the next Mining School to contine its traditions was instituted not earlier than in 1889 in Dabrowa Gornicza. It was also known as the Mine Foreman or Mine Deputy School (Sztygarka). This School was closed in 1905, reopened in 1910 and closed again in 1914. After Poland regained independence in 1919 the School flourished for 20 years. During the Second World War the teaching staff and student body were decimated and facilities destroyed. After 1945 the School was rebuilt and developed into an engineering school as a branch of the Academy of Mining and Metallury in Cracow by 1968 and a branch of the Silesian Politechnical between 1968 and 1984. In 1985 the School was taken over by the Ministry of Mining and Power Engineering and reorganized as a mining trade school. The Mining School in Dabrowa Gornicza, where several prominent professors of geology and managers of Polish geological and mining enterprises began their careers, contributed greatly to the development of geology in Poland. 12 refs.

North American Bats and Mines Project: A cooperative approach for integrating bat conservation and mine-land reclamation

Energy Technology Data Exchange (ETDEWEB)

Ducummon, S.L. [Bat Conservation International, Austin, TX (United States)

1997-12-31

Inactive underground mines now provide essential habitat for more than half of North America`s 44 bat species, including some of the largest remaining populations. Thousands of abandoned mines have already been closed or are slated for safety closures, and many are destroyed during renewed mining in historic districts. The available evidence suggests that millions of bats have already been lost due to these closures. Bats are primary predators of night-flying insects that cost American farmers and foresters billions of dollars annually, therefore, threats to bat survival are cause for serious concern. Fortunately, mine closure methods exist that protect both bats and humans. Bat Conservation International (BCI) and the USDI-Bureau of Land Management founded the North American Bats and Mines Project to provide national leadership and coordination to minimize the loss of mine-roosting bats. This partnership has involved federal and state mine-land and wildlife managers and the mining industry. BCI has trained hundreds of mine-land and wildlife managers nationwide in mine assessment techniques for bats and bat-compatible closure methods, published technical information on bats and mine-land management, presented papers on bats and mines at national mining and wildlife conferences, and collaborated with numerous federal, state, and private partners to protect some of the most important mine-roosting bat populations. Our new mining industry initiative, Mining for Habitat, is designed to develop bat habitat conservation and enhancement plans for active mining operations. It includes the creation of cost-effective artificial underground bat roosts using surplus mining materials such as old mine-truck tires and culverts buried beneath waste rock.

WIRELESS MINE-WIDE TELECOMMUNICATIONS TECHNOLOGY

Energy Technology Data Exchange (ETDEWEB)

Zvi H. Meiksin

2004-03-01

A comprehensive mine-wide, two-way wireless voice and data communication system for the underground mining industry was developed. The system achieves energy savings through increased productivity and greater energy efficiency in meeting safety requirements within mines. The mine-wide system is comprised of two interfaced subsystems: a through-the-earth communications system and an in-mine communications system. The mine-wide system permits two-way communication among underground personnel and between underground and surface personnel. The system was designed, built, and commercialized. Several systems are in operation in underground mines in the United States. The use of these systems has proven they result in considerable energy savings. A system for tracking the location of vehicles and people within the mine was also developed, built and tested successfully. Transtek's systems are being used by the National Institute of Occupational Safety and Health (NIOSH) in their underground mine rescue team training program. This project also resulted in a spin-off rescue team lifeline and communications system. Furthermore, the project points the way to further developments that can lead to a GPS-like system for underground mines allowing the use of autonomous machines in underground mining operations, greatly reducing the amount of energy used in these operations. Some products developed under this program are transferable to applications in fields other than mining. The rescue team system is applicable to use by first responders to natural, accidental, or terrorist-caused building collapses. The in-mine communications system can be installed in high-rise buildings providing in-building communications to security and maintenance personnel as well as to first responders.

Mine waste management legislation. Gold mining areas in Romania

Science.gov (United States)

Maftei, Raluca-Mihaela; Filipciuc, Constantina; Tudor, Elena

2014-05-01

Problems in the post-mining regions of Eastern Europe range from degraded land and landscapes, huge insecure dumps, surface cracks, soil pollution, lowering groundwater table, deforestation, and damaged cultural potentials to socio economic problems like unemployment or population decline. There is no common prescription for tackling the development of post-mining regions after mine closure nor is there a common definition of good practices or policy in this field. Key words : waste management, legislation, EU Directive, post mining Rosia Montana is a common oh 16 villages; one of them is also called Rosia Montana, a traditional mining Community, located in the Apuseni Mountains in the North-Western Romania. Beneath part of the village area lays one of the largest gold and silver deposits in Europe. In the Rosia Montana area mining had begun ever since the height of the Roman Empire. While the modern approach to mining demands careful remediation of environmental impacts, historically disused mines in this region have been abandoned, leaving widespread environmental damage. General legislative framework Strict regulations and procedures govern modern mining activity, including mitigation of all environmental impacts. Precious metals exploitation is put under GO no. 190/2000 re-published in 2004. The institutional framework was established and organized based on specific regulations, being represented by the following bodies: • The Ministry of Economy and Commerce (MEC), a public institution which develops the Government policy in the mining area, also provides the management of the public property in the mineral resources area; • The National Agency for the development and implementation of the mining Regions Reconstruction Programs (NAD), responsible with promotion of social mitigation measures and actions; • The Office for Industry Privatization, within the Education Ministry, responsible with privatization of companies under the CEM; • The National

30 CFR 77.1200 - Mine map.

Science.gov (United States)

2010-07-01

... SAFETY STANDARDS, SURFACE COAL MINES AND SURFACE WORK AREAS OF UNDERGROUND COAL MINES Maps § 77.1200 Mine...) The location of railroad tracks and public highways leading to the mine, and mine buildings of a permanent nature with identifying names shown; (k) Underground mine workings underlying and within 1,000...

Rapid Evaluation of Radioactive Contamination in Rare Earth Mine Mining

Science.gov (United States)

Wang, N.

2017-12-01

In order to estimate the current levels of environmental radioactivity in Bayan Obo rare earth mine and to study the rapid evaluation methods of radioactivity contamination in the rare earth mine, the surveys of the in-situ gamma-ray spectrometry and gamma dose rate measurement were carried out around the mining area and living area. The in-situ gamma-ray spectrometer was composed of a scintillation detector of NaI(Tl) (Φ75mm×75mm) and a multichannel analyzer. Our survey results in Bayan Obo Mine display: (1) Thorium-232 is the radioactive contamination source of this region, and uranium-238 and potassium - 40 is at the background level. (2) The average content of thorium-232 in the slag of the tailings dam in Bayan Obo is as high as 276 mg/kg, which is 37 times as the global average value of thorium content. (3) We found that the thorium-232 content in the soil in the living area near the mining is higher than that in the local soil in Guyang County. The average thorium-232 concentrations in the mining areas of the Bayan Obo Mine and the living areas of the Bayan Obo Town were 18.7±7.5 and 26.2±9.1 mg/kg, respectively. (4) It was observed that thorium-232 was abnormal distributed in the contaminated area near the tailings dam. Our preliminary research results show that the in-situ gamma-ray spectrometry is an effective approach of fast evaluating rare earths radioactive pollution, not only can the scene to determine the types of radioactive contamination source, but also to measure the radioactivity concentration of thorium and uranium in soil. The environmental radioactive evaluation of rare earth ore and tailings dam in open-pit mining is also needed. The research was supported by National Natural Science Foundation of China (No. 41674111).

Mine water treatment in Donbass

Energy Technology Data Exchange (ETDEWEB)

Azarenkov, P A; Anisimov, V M; Krol, V A

1980-10-01

About 2,000,000 m$SUP$3 of mine water are discharged by coal mines yearly to surface waters in the Donbass. Mine water in the region is rich in mineral salts and suspended matter (coal and rock particles). The DonUGI Institute developed a system of mine water treatment which permits the percentage of suspended matter to be reduced to 1.5 mg/l. The treated mine water can be used in fire fighting and in dust suppression systems in coal mines. A scheme of the water treatment system is shown. It consists of the following stages: reservoir of untreated mine water, chamber where mine water is mixed with reagents, primary sedimentation tanks, sand filters, and chlorination. Aluminium sulphate is used as a coagulation agent. To intensify coagulation polyacrylamide is added. Technical specifications of surface structures in which water treatment is carried out are discussed. Standardized mine water treatment systems with capacities of 600 m$SUP$3/h, with 900, 1200, 1500, 1800 and 2100 m$SUP$3/h capacities are used. (In Russian)

Open pit mining of uranium

International Nuclear Information System (INIS)

Wood, J.T.

1977-01-01

The Jackpile--Paquate Mines of the Anaconda Company are on the Laguna Indian Reservation midway between Grants and Albuquerque, New Mexico. The open pit mining of uranium ore at those mines is conducted in three separate operations (stripping, mining, and ore haul)

Radiation in mines

International Nuclear Information System (INIS)

Rose, H.J.M.

1982-01-01

Radiation in mines is primarily associated with, but not restricted to, the exploitation of uranium bearing orebodies. The intent of this chapter is to convey some aspects of radiation control in the mining industry, the behaviour of the parent radon and its daughter products. An attempt was made to demonstrate that anything less than complete diligence by the ventilation personnel could result in rapid deterioration of the mine environment, and consequently high exposure rates. When the maximum annual exposure limit is 4,0 WLM (Working level month exposure) the ventilation official is not allowed the privilege of making an error. Ventilation planning in uranium mines is of prime importance and is very much a group involvement

Geologic mapping around Mahoma mining. San Jose mining company

International Nuclear Information System (INIS)

Techera, J.; Arrighetii, R.

1993-01-01

This study has as main objective carry out a geological mapping as well as the structural analysis , in 1.5.000 scale in the zone where the gold benefit plant of San Jose mining company is settled (Mahoma Mining). From this study has been marked many drillings.

Ghana Mining Journal: Contact

African Journals Online (AJOL)

Principal Contact. Professor Daniel Mireku-Gyimah Editor-in-Chief University of Mines & Technology Ghana Mining Journal University of Mines & Technology P. O. BOX 237 Tarkwa Ghana Phone: +233 362 20280/20324. Fax: +233 362 20306. Email: dm.gyimah@umat.edu.gh ...

Mining in El Salvador

DEFF Research Database (Denmark)

Pacheco Cueva, Vladimir

2014-01-01

In this guest article, Vladimir Pacheco, a social scientist who has worked on mining and human rights shares his perspectives on a current campaign against mining in El Salvador – Central America’s smallest but most densely populated country.......In this guest article, Vladimir Pacheco, a social scientist who has worked on mining and human rights shares his perspectives on a current campaign against mining in El Salvador – Central America’s smallest but most densely populated country....

Mine for sale

International Nuclear Information System (INIS)

Beer, G.

2006-01-01

The newest Slovak brown coal mine - Bana Zahorie is in crisis. Despite the fact that experts believe that along with Bana Novaky, it has the most potential. The owners have started its liquidation. One of the walls has collapsed and another part flooded. Nobody was hurt, but some equipment is still underground. The mine had already lost equipment in the past. During an accident in 2000, equipment worth several tens of millions was destroyed. 'After the accident, mining had to be stopped and from a technical point of view that was the end of the joint stock company, Bana Zahorie Cary. The company could not raise the funds necessary to recover from the accident,' stated the Director of the mine, Jan Palkovic. But he stressed that only the joint stock company is in liquidation, the mine is still being ventilated and the water is being pumped out. But the company management still does not want to specify who will become the new owner of the lignite deposits in Zahorie. The Director promised to publish more details within several weeks. All competencies and mining rights of the former Bana Zahorie are being transferred to a new company - joint stock company Bana Cary. (author)

Mining in 2015

Energy Technology Data Exchange (ETDEWEB)

Hood, M.; Hatherly, P.; Gurgenci, H. [Centre for Mining Technology and Equipment (Australia)

1999-10-01

New technology in open-pit and underground hard rock mining in 2015 is anticipated in this article, based on a paper presented to the 1998 invitation symposium - 'Technology - Australia's future: new technology for traditional industry', held in Freemantle, WA, 24-25 November 1998. It is expected that essential mining operations of rock breakage and transport and ore processing will still exist but the use of drills, shovels/LHDs and trucks is likely to be replaced by continuous, intelligent, automated mining systems. Rock blasting models need to be fed data on rock properties at each blasthole for high accuracy. The authors believe that in 2015 measurements of rock properties will be a routine part of the drilling process. Blasthole drills will be fitted with a range of mechanical and geophysical sensors. New, non-explosive methods of rock breaking such as oscillating disc cutting, may be available. Mining automation will improve safety and productivity, perhaps with the automation of dragline swing LHDs and trucks may be able to drive themselves, with operators monitoring and intervening when necessary. Performance and machine condition data may be applied to improve equipment design. Australian mining stands to gain by these advances in mining technology. 1 fig., 3 photos.

Preparatory mining and geotechnical work for safe closure of the Asse mine

International Nuclear Information System (INIS)

Schmidt, M.W.; Schauermann, V.; Kappei, G.

2002-01-01

After the GSF Research Centre for Environment and Health discontinued its own research into the safe ultimate storage of waste hazardous to the environment in deep geological formations and the work of the Institute for Deep Storage was likewise suspended there is no longer any need to continue operation of the Asse mine for research purposes. Hence the closure of the mine is being prepared on the basis of the Federal Mining Act. The GSF accordingly has to submit a final operating plan, with which a comprehensive safety report containing inter alia proof of the long-time safety should be enclosed. The proof should be furnished according to the specific location and takes into account the geological, hydrogeological, geochemical, geotechnical, mining-related conditions and the radionuclide inventory in the Asse mine. (orig.) [de

Environmental geochemistry of acid mine drainage water at Indus coal mine at Lakhra, Sindh Pakistan

International Nuclear Information System (INIS)

Siddique, I.; Shah, M.T.

2000-01-01

The annual coal production of Pakistan is about 3,637, 825 tones which is about 6% of the country's energy resources, out of this 1,241, 965 tones of coal was produced/ mined from the Lakhra coal field, District Dadu, Sindh which after the Thar coal field is the second largest coal field of Pakistan. At this coal field more than 58 mining companies are engaged in exploring the hidden wealth of the country. The problem of acid mine drainage, is caused by the passage or seepage of water, through mines where iron disulfides, usually pyrites, are exposed to the oxidizing action of water, air and bacteria, is the main problem faced by the mining companies. The geochemical analysis of acid mine drainage water collected from Indus coal mine no. 6 shows that beside its higher pH, total Dissolved Solids and Sulfates, it also posses higher amount of heavy metals like Cd, Cu, Pb, Co, Ni and Fe. This acid mine drainage water not only damages the mine structures but is also harmful to soil and ecology. (author)

Influence of Mining Thickness on the Rationality of Upward Mining in Coal Seam Group

Directory of Open Access Journals (Sweden)

Y. Li

2016-04-01

Full Text Available This study aimed to determine the influence of mining thickness on the rationality of upward mining in coal seam group. Numerical simulation and theoretical analysis were performed to investigate the influence of the mining thicknesses of initial mining seam on the destruction and pressure relief effect of the upper coal seam in a high-gas coal seam group. The mechanical model of the roof failure based on the mining thickness was established by assuming that the gob formed after adjacent panels have fully been caved is the infinite plane. On the basis of this model, an equation was derived to calculate the roof failure height of the panel. Considering the geological conditions of No. 9 and No. 12 coal seams of Zhaogezhuang Coal Mine, economic effectiveness, and proposed techniques, we concluded that the top layer (4 m of the No. 12 coal seam should be mined first. The top layer of the No. 9 coal seam should be subsequently mined. The topcaving technique was applied to the exploitation of the lower layer of the No. 12 coal seam. Practically monitored data revealed that the deformation and failure of the No. 2699 panel roadway was small and controllable, the amount of gas emission was reduced significantly, and the effect of upward mining was active. The results of this study provide theory basics for mine designing, and it is the provision of a reference for safe and efficient coal exploitation under similar conditions.

Mining compressing sequential problems

NARCIS (Netherlands)

Hoang, T.L.; Mörchen, F.; Fradkin, D.; Calders, T.G.K.

2012-01-01

Compression based pattern mining has been successfully applied to many data mining tasks. We propose an approach based on the minimum description length principle to extract sequential patterns that compress a database of sequences well. We show that mining compressing patterns is NP-Hard and

Construction over abandoned mine workings

Energy Technology Data Exchange (ETDEWEB)

Healy, P R; Head, J M

1984-01-01

Guidance is given for engineers involved with the planning and development of sites previously undermined for coal and other minerals. Past methods of mining employed in Britain are described, and their short- and long-term effects on surface stability are assessed. Where modern methods of mining are relevant, or where structural design techniques for the surface effects of mining can be applied, these are included for illustration and completeness. Additional objectives over and above those for conventional site investigations are identified, and details are provided for the planning and execution of a mining investigation. Techniques for consolidation of old mine workings and remedial measures for mine shafts are described. Foundation design options are included for cases where expected ground movements can be accommodated. A comprehensive guide to sources of information on previous mining is presented, together with an example of a specification suitable for the consolidation of old shallow mine workings. (50 refs.)

Personal continuous route pattern mining

Institute of Scientific and Technical Information of China (English)

Qian YE; Ling CHEN; Gen-cai CHEN

2009-01-01

In the daily life, people often repeat regular routes in certain periods. In this paper, a mining system is developed to find the continuous route patterns of personal past trips. In order to count the diversity of personal moving status, the mining system employs the adaptive GPS data recording and five data filters to guarantee the clean trips data. The mining system uses a client/server architecture to protect personal privacy and to reduce the computational load. The server conducts the main mining procedure but with insufficient information to recover real personal routes. In order to improve the scalability of sequential pattern mining, a novel pattern mining algorithm, continuous route pattern mining (CRPM), is proposed. This algorithm can tolerate the different disturbances in real routes and extract the frequent patterns. Experimental results based on nine persons' trips show that CRPM can extract more than two times longer route patterns than the traditional route pattern mining algorithms.

Post-mining safety implementations and environmental aspects of abandoned mine sites in Limousin. 2006 status (and perspectives 2007)

International Nuclear Information System (INIS)

2007-01-01

This document summarizes the actions carried out in 2006 at some French abandoned mine sites: 1 - safety implementations and risks abatement in the framework of post-mining actions: coal mines of Ahun (23) and Argentat (19), antimony mines of Biard (87); 2 - remedial actions at the tin/tungsten mine of Puy-les-Vignes (87) and at the gold mine of Chatelet (23); 3 - 2007 post-mining perspectives; 4 - environmental aspects of abandoned mine sites: gold mines of Chatelet (23), Cheni and Bourneix (87), uranium mines of Haute-Vienne (expertise, control of effluents, financial warranties about tailings storage sites maintenance). (J.S.)

Economic impact of world mining

International Nuclear Information System (INIS)

Walser, G.

2002-01-01

Mining plays a vital role in the economic development of many countries. The emerging economies are now major players in the production and availability of key commodities such as copper (70%), bauxite (40%), iron ore and precious metals. Mining also has a positive impact on the economy of many countries. Another impact of mining can be measured in terms of employment opportunities and income generation. Commercial scale mining provides employment and skills transfer to more than 2 million workers. The multiplier effect increases this benefit by a factor of between 2 and 5. The World Bank Mining Department has carried out an in-depth study on economic and social impact of mining at the community level in Chile, Peru, Bolivia, Papua New Guinea and Mali. This study demonstrates that there are substantial social and economic benefits to the community. The most positive cases are related to the growth of local small- and micro-enterprise activities. However, mining remains controversial, as true sustainable development is not only a matter of financial flows. Mining has also been associated with a number of economic and social problems. As a result there are questions about the sustainability of the economic outcome of mining. The contribution of mining to sustainable development needs to be considered in terms of economic and technical viability, ecological sustainability and social equity. To achieve this, governments, mining companies and local communities must work together to address these issues. (author)

Applications of Geomatics in Surface Mining

Science.gov (United States)

Blachowski, Jan; Górniak-Zimroz, Justyna; Milczarek, Wojciech; Pactwa, Katarzyna

2017-12-01

In terms of method of extracting mineral from deposit, mining can be classified into: surface, underground, and borehole mining. Surface mining is a form of mining, in which the soil and the rock covering the mineral deposits are removed. Types of surface mining include mainly strip and open-cast methods, as well as quarrying. Tasks associated with surface mining of minerals include: resource estimation and deposit documentation, mine planning and deposit access, mine plant development, extraction of minerals from deposits, mineral and waste processing, reclamation and reclamation of former mining grounds. At each stage of mining, geodata describing changes occurring in space during the entire life cycle of surface mining project should be taken into consideration, i.e. collected, analysed, processed, examined, distributed. These data result from direct (e.g. geodetic) and indirect (i.e. remote or relative) measurements and observations including airborne and satellite methods, geotechnical, geological and hydrogeological data, and data from other types of sensors, e.g. located on mining equipment and infrastructure, mine plans and maps. Management of such vast sources and sets of geodata, as well as information resulting from processing, integrated analysis and examining such data can be facilitated with geomatic solutions. Geomatics is a discipline of gathering, processing, interpreting, storing and delivering spatially referenced information. Thus, geomatics integrates methods and technologies used for collecting, management, processing, visualizing and distributing spatial data. In other words, its meaning covers practically every method and tool from spatial data acquisition to distribution. In this work examples of application of geomatic solutions in surface mining on representative case studies in various stages of mine operation have been presented. These applications include: prospecting and documenting mineral deposits, assessment of land accessibility

Environmental laws for mining activities in Provincia de San Juan (Argentina), gravel mines exploitation

International Nuclear Information System (INIS)

Ramirez, M.; Carrascosa, H.

2007-01-01

This paper analyses San Juan Province - Argentina prevailing environmental legislation for mining activity and gravel mines. The study focuses the subject from a mining engineering point of view. (author)

Abandoned Uranium Mine (AUM) Trust Mine Points, Navajo Nation, 2016, US EPA Region 9

Data.gov (United States)

U.S. Environmental Protection Agency — This GIS dataset contains point features that represent mines included in the Navajo Environmental Response Trust. This mine category also includes Priority mines....

Steam coal mines of tomorrow

Energy Technology Data Exchange (ETDEWEB)

McCloskey, G

1986-07-01

A comprehensive review of new steam coal mines being planned or developed worldwide. It shows that at least 20 major mines with a combined annual output of 110 million tonnes per annum, could add their coal to world markets in the next 10 years. The review highlights: substantial activity in Australia with at least four major mines at advanced planning stages; a strengthening of the South American export industry with 4 major mines operating in 10 years compared with just one today; no major export mines being developed in the traditional US mining areas; and the emergence of Indonesia as a major steam coal producer/exporter. The review also shows a reduction in cost/output ratios, and also the proximity of the new mines to existing infrastructure (e.g. export terminals, rail links).

Application of EREP imagery to fracture-related mine safety hazards and environmental problems in mining

Science.gov (United States)

Wier, C. E.; Wobber, F. J.; Amato, R. V.; Russell, O. R. (Principal Investigator)

1973-01-01

The author has identified the following significant results. Numerous fracture traces were detected on both the color transparencies and black and white spectral bands. Fracture traces of value to mining hazards analysis were noted on the EREP imagery which could not be detected on either the ERTS-1 or high altitude aircraft color infrared photography. Several areas of mine subsidence occurring in the Busseron Creek area near Sullivan, Indiana were successfully identified using color photography. Skylab photography affords an increase over comparable scale ERTS-1 imagery in level of information obtained in mined lands inventory and reclamation analysis. A review of EREP color photography permitted the identification of a substantial number of non-fuel mines within the Southern Indiana test area. A new mine was detected on the EREP photography without prior data. EREP has definite value for estimating areal changes in active mines and for detecting new non-fuel mines. Gob piles and slurry ponds of several acres could be detected on the S-190B color photography when observed in association with large scale mining operations. Apparent degradation of water quality resulting from acid mine drainage and/or siltation was noted in several ponds or small lakes and appear to be related to intensive mining activity near Sullivan, Indiana.

Data mining applications in healthcare.

Science.gov (United States)

Koh, Hian Chye; Tan, Gerald

2005-01-01

Data mining has been used intensively and extensively by many organizations. In healthcare, data mining is becoming increasingly popular, if not increasingly essential. Data mining applications can greatly benefit all parties involved in the healthcare industry. For example, data mining can help healthcare insurers detect fraud and abuse, healthcare organizations make customer relationship management decisions, physicians identify effective treatments and best practices, and patients receive better and more affordable healthcare services. The huge amounts of data generated by healthcare transactions are too complex and voluminous to be processed and analyzed by traditional methods. Data mining provides the methodology and technology to transform these mounds of data into useful information for decision making. This article explores data mining applications in healthcare. In particular, it discusses data mining and its applications within healthcare in major areas such as the evaluation of treatment effectiveness, management of healthcare, customer relationship management, and the detection of fraud and abuse. It also gives an illustrative example of a healthcare data mining application involving the identification of risk factors associated with the onset of diabetes. Finally, the article highlights the limitations of data mining and discusses some future directions.

Security Measures in Data Mining

OpenAIRE

Anish Gupta; Vimal Bibhu; Rashid Hussain

2012-01-01

Data mining is a technique to dig the data from the large databases for analysis and executive decision making. Security aspect is one of the measure requirement for data mining applications. In this paper we present security requirement measures for the data mining. We summarize the requirements of security for data mining in tabular format. The summarization is performed by the requirements with different aspects of security measure of data mining. The performances and outcomes are determin...

Injection of FGD Grout to Abate Acid Mine Drainage in Underground Coal Mines

Energy Technology Data Exchange (ETDEWEB)

Mafi, S.; Damian, M.T.; Senita, R.E.; Jewitt, W.C.; Bair, S.; Chin, Y.C.; Whitlatch, E.; Traina, S.; Wolfe, W.

1997-07-01

Acid Mine Drainage (AMD) from abandoned underground coal mines in Ohio is a concern for both residents and regulatory agencies. Effluent from these mines is typically characterized by low pH and high iron and sulfate concentrations and may contaminate local drinking-water supplies and streams. The objective of this project is to demonstrate the technical feasibility of injecting cementitious alkaline materials, such as Flue Gas Desulfurization (FGD) material to mitigate current adverse environmental impacts associated with AMD in a small, abandoned deep mine in Coshocton County Ohio. The Flue Gas Desulfurization material will be provided from American Electric Power`s (AEP) Conesville Plant. It will be injected as a grout mix that will use Fixated Flue Gas Desulfurization material and water. The subject site for this study is located on the border of Coshocton and Muskingum Counties, Ohio, approximately 1.5 miles south-southwest of the town of Wills Creek. The study will be performed at an underground mine designated as Mm-127 in the Ohio Department of Natural Resources register, also known as the Roberts-Dawson Mine. The mine operated in the mid-1950s, during which approximately 2 million cubic feet of coal was removed. Effluent discharging from the abandoned mine entrances has low pH in the range of 2.8-3.0 that drains directly into Wills Creek Lake. The mine covers approximately 14.6 acres. It is estimated that 26,000 tons of FGD material will be provided from AEP`s Conesville Power Plant located approximately 3 miles northwest of the subject site.

Injection of FGD Grout to Abate Acid Mine Drainage in Underground Coal Mines

International Nuclear Information System (INIS)

Mafi, S.; Damian, M.T.; Senita, R.E.; Jewitt, W.C.; Bair, S.; Chin, Y.C.; Whitlatch, E.; Traina, S.; Wolfe, W.

1997-07-01

Acid Mine Drainage (AMD) from abandoned underground coal mines in Ohio is a concern for both residents and regulatory agencies. Effluent from these mines is typically characterized by low pH and high iron and sulfate concentrations and may contaminate local drinking-water supplies and streams. The objective of this project is to demonstrate the technical feasibility of injecting cementitious alkaline materials, such as Flue Gas Desulfurization (FGD) material to mitigate current adverse environmental impacts associated with AMD in a small, abandoned deep mine in Coshocton County Ohio. The Flue Gas Desulfurization material will be provided from American Electric Power's (AEP) Conesville Plant. It will be injected as a grout mix that will use Fixated Flue Gas Desulfurization material and water. The subject site for this study is located on the border of Coshocton and Muskingum Counties, Ohio, approximately 1.5 miles south-southwest of the town of Wills Creek. The study will be performed at an underground mine designated as Mm-127 in the Ohio Department of Natural Resources register, also known as the Roberts-Dawson Mine. The mine operated in the mid-1950s, during which approximately 2 million cubic feet of coal was removed. Effluent discharging from the abandoned mine entrances has low pH in the range of 2.8-3.0 that drains directly into Wills Creek Lake. The mine covers approximately 14.6 acres. It is estimated that 26,000 tons of FGD material will be provided from AEP's Conesville Power Plant located approximately 3 miles northwest of the subject site

Methane emissions from coal mining

International Nuclear Information System (INIS)

Boyer, C.M.; Kelafant, J.R.; Kuuskraa, V.A.; Manger, K.C.; Kruger, D.

1990-09-01

The report estimates global methane emissions from coal mining on a country specific basis, evaluates the technologies available to degasify coal seams and assesses the economics of recovering methane liberated during mining. 33 to 64 million tonnes were liberated in 1987 from coal mining, 75 per cent of which came from China, the USSR, Poland and the USA. Methane emissions from coal mining are likely to increase. Emission levels vary between surface and underground mines. The methane currently removed from underground mines for safety reasons could be used in a number of ways, which may be economically attractive. 55 refs., 19 figs., 24 tabs

Data mining in Cloud Computing

Directory of Open Access Journals (Sweden)

Ruxandra-Ştefania PETRE

2012-10-01

Full Text Available This paper describes how data mining is used in cloud computing. Data Mining is used for extracting potentially useful information from raw data. The integration of data mining techniques into normal day-to-day activities has become common place. Every day people are confronted with targeted advertising, and data mining techniques help businesses to become more efficient by reducing costs.Data mining techniques and applications are very much needed in the cloud computing paradigm. The implementation of data mining techniques through Cloud computing will allow the users to retrieve meaningful information from virtually integrated data warehouse that reduces the costs of infrastructure and storage.

Mining highly stressed areas, part 2.

CSIR Research Space (South Africa)

Johnson, R

1995-12-01

Full Text Available A questionnaire related to mining at great depth and in very high stress conditions has been completed with the assistance of mine rock mechanics personnel on over twenty mines in all mining districts, and covering all deep level mines...

Factors influencing mine rescue team behaviors.

Science.gov (United States)

Jansky, Jacqueline H; Kowalski-Trakofler, K M; Brnich, M J; Vaught, C

2016-01-01

A focus group study of the first moments in an underground mine emergency response was conducted by the National Institute for Occupational Safety and Health (NIOSH), Office for Mine Safety and Health Research. Participants in the study included mine rescue team members, team trainers, mine officials, state mining personnel, and individual mine managers. A subset of the data consists of responses from participants with mine rescue backgrounds. These responses were noticeably different from those given by on-site emergency personnel who were at the mine and involved with decisions made during the first moments of an event. As a result, mine rescue team behavior data were separated in the analysis and are reported in this article. By considering the responses from mine rescue team members and trainers, it was possible to sort the data and identify seven key areas of importance to them. On the basis of the responses from the focus group participants with a mine rescue background, the authors concluded that accurate and complete information and a unity of purpose among all command center personnel are two of the key conditions needed for an effective mine rescue operation.

Underground mining of the lower 163 zone through groundwater drainage at the Eagle Point Mine

International Nuclear Information System (INIS)

Robson, D.M.; Bashir, R.; Thomson, J.; Klemmer, S.; Rigden, A.

2010-01-01

The Eagle Point Mine is part of the Cameco Rabbit Lake Operation. The mine produces uranium ore using the long-hole, vertical and horizontal retreat mining method. The majority of the mine workings are under Wollaston Lake and cementitious grouting is used as one of the water control measures. Historical groundwater table in the mining area was close to ground surface. The Lower 163 Zone encompasses an estimated 4.2 million pounds U_3O_8 geological resource that was not considered feasible to mine due to the expected groundwater flows in the area. Cross-hole testing was conducted to better understand the groundwater flow through various geologic units. A local depressurization test was conducted to assess the potential for lowering the water table. Following testing an active depressurization was conducted to lower the groundwater table below the planned mining areas. This resulted in safe and drier mining conditions and allowed for the successful extraction of the ore body. (author)

A partition enhanced mining algorithm for distributed association rule mining systems

Directory of Open Access Journals (Sweden)

A.O. Ogunde

2015-11-01

Full Text Available The extraction of patterns and rules from large distributed databases through existing Distributed Association Rule Mining (DARM systems is still faced with enormous challenges such as high response times, high communication costs and inability to adapt to the constantly changing databases. In this work, a Partition Enhanced Mining Algorithm (PEMA is presented to address these problems. In PEMA, the Association Rule Mining Coordinating Agent receives a request and decides the appropriate data sites, partitioning strategy and mining agents to use. The mining process is divided into two stages. In the first stage, the data agents horizontally segment the databases with small average transaction length into relatively smaller partitions based on the number of available sites and the available memory. On the other hand, databases with relatively large average transaction length were vertically partitioned. After this, Mobile Agent-Based Association Rule Mining-Agents, which are the mining agents, carry out the discovery of the local frequent itemsets. At the second stage, the local frequent itemsets were incrementally integrated by the from one data site to another to get the global frequent itemsets. This reduced the response time and communication cost in the system. Results from experiments conducted on real datasets showed that the average response time of PEMA showed an improvement over existing algorithms. Similarly, PEMA incurred lower communication costs with average size of messages exchanged lower when compared with benchmark DARM systems. This result showed that PEMA could be efficiently deployed for efficient discovery of valuable knowledge in distributed databases.

The mines of Jackymov

International Nuclear Information System (INIS)

Ramsey, L.J.

1985-01-01

The history of the mines in the vicinity of Jackymov, a small town in Central Europe is given. These mines have been worked for several hundred years and from them has been brought forth a variety of products including silver, uranium and radium, the latter being isolated from Jackymov pitch-blende and identified by Marie Curie. The health effects of the miners mining radioactive ores are briefly discussed. The development of Jackymov as a spa resort using the mine water containing radium is also described. (U.K.)

Uranium mining and milling

International Nuclear Information System (INIS)

Floeter, W.

1976-01-01

In this report uranium mining and milling are reviewed. The fuel cycle, different types of uranium geological deposits, blending of ores, open cast and underground mining, the mining cost and radiation protection in mines are treated in the first part of this report. In the second part, the milling of uranium ores is treated, including process technology, acid and alkaline leaching, process design for physical and chemical treatment of the ores, and the cost. Each chapter is clarified by added figures, diagrams, tables, and flowsheets. (HK) [de

Leaching characteristics of vanadium in mine tailings and soils near a vanadium titanomagnetite mining site

Energy Technology Data Exchange (ETDEWEB)

Yang, Jinyan; Tang, Ya; Yang, Kai [College of Architecture and Environment, Sichuan University, Chengdu 610065 (China); Rouff, Ashaki A. [School of Earth and Environmental Sciences, Queens College City University of New York, 65-30 Kissena Boulevard, Flushing, NY 11367 (United States); Elzinga, Evert J. [Department of Earth and Environmental Sciences, Rutgers University, Newark, NJ (United States); Huang, Jen-How, E-mail: jen-how.huang@unibas.ch [Institute of Environmental Geosciences, University of Basel, CH-4056 Basel (Switzerland)

2014-01-15

Highlights: • Vanadium in the soil and mine tailings has low solubility. • The leachability of vanadium in the mine tailings is lower than in the soil. • Low risk of vanadium migrating from the soil and mine tailings into the surrounding environment. • Drought and rewetting increase vanadium release from the soil and mine tailings. • Soil leaching processes control vanadium transport in soils overlain with mine tailings. -- Abstract: A series of column leaching experiments were performed to understand the leaching behaviour and the potential environmental risk of vanadium in a Panzhihua soil and vanadium titanomagnetite mine tailings. Results from sequential extraction experiments indicated that the mobility of vanadium in both the soil and the mine tailings was low, with <1% of the total vanadium readily mobilised. Column experiments revealed that only <0.1% of vanadium in the soil and mine tailing was leachable. The vanadium concentrations in the soil leachates did not vary considerably, but decreased with the leachate volume in the mine tailing leachates. This suggests that there was a smaller pool of leachable vanadium in the mine tailings compared to that in the soil. Drought and rewetting increased the vanadium concentrations in the soil and mine tailing leachates from 20 μg L{sup −1} to 50–90 μg L{sup −1}, indicating the potential for high vanadium release following periods of drought. Experiments with soil columns overlain with 4, 8 and 20% volume mine tailings/volume soil exhibited very similar vanadium leaching behaviour. These results suggest that the transport of vanadium to the subsurface is controlled primarily by the leaching processes occurring in soils.

Coal Mines, Reclamation Sites - Mine Drainage Treatment/Land Recycling Project Locations

Data.gov (United States)

NSGIC Education | GIS Inventory — Mine Drainage Treatment/Land Reclamation Locations are clean-up projects that are working to eliminate some form of abandoned mine. The following sub-facility types...

Introduction of an automated mine surveying system - a method for effective control of mining operations

Energy Technology Data Exchange (ETDEWEB)

Mazhdrakov, M.

1987-04-01

Reviews developments in automated processing of mine survey data in Bulgaria for 1965-1970. This development has occurred in three phases. In the first phase, computers calculated coordinates of mine survey points; in the second phase, these data were electronically processed; in the third phase, surface and underground mine development is controlled by electronic data processing equipment. Centralized and decentralized electronic processing of data has been introduced at major coal mines. The Bulgarian Pravets 82 microcomputer and the ASMO-MINI program package are in current use at major coal mines. A lack of plotters, due to financial limitations, handicaps large-scale application of automated mine surveying in Bulgaria.

Data Mining for CRM

Science.gov (United States)

Thearling, Kurt

Data Mining technology allows marketing organizations to better understand their customers and respond to their needs. This chapter describes how Data Mining can be combined with customer relationship management to help drive improved interactions with customers. An example showing how to use Data Mining to drive customer acquisition activities is presented.

Implications of Emerging Data Mining

Science.gov (United States)

Kulathuramaiyer, Narayanan; Maurer, Hermann

Data Mining describes a technology that discovers non-trivial hidden patterns in a large collection of data. Although this technology has a tremendous impact on our lives, the invaluable contributions of this invisible technology often go unnoticed. This paper discusses advances in data mining while focusing on the emerging data mining capability. Such data mining applications perform multidimensional mining on a wide variety of heterogeneous data sources, providing solutions to many unresolved problems. This paper also highlights the advantages and disadvantages arising from the ever-expanding scope of data mining. Data Mining augments human intelligence by equipping us with a wealth of knowledge and by empowering us to perform our daily tasks better. As the mining scope and capacity increases, users and organizations become more willing to compromise privacy. The huge data stores of the ‚master miners` allow them to gain deep insights into individual lifestyles and their social and behavioural patterns. Data integration and analysis capability of combining business and financial trends together with the ability to deterministically track market changes will drastically affect our lives.

Impact of type of the roof rocks on location and range of endogenous fires particular hazard zone by in goaf with caving

Science.gov (United States)

Tutak, Magdalena; Brodny, Jarosław

2018-01-01

Hazard of endogenous fires is one of the basic and common presented occupational safety hazards in coal mine in Poland and in the world. This hazard means possibility of coal self-ignition as the result of its self-heating process in mining heading or its surrounding. In underground coal-mining during ventilating of operating longwalls takes place migration of parts of airflow to goaf with caving. In a case when in these goaf a coal susceptible to self-ignition occurs, then the airflow through these goaf may influence on formation of favorable conditions for coal oxidation and subsequently to its self-heating and self-ignition. Endogenous fire formed in such conditions can pose a serious hazards for the crew and for continuity of operation of mining plant. From the practical point of view a very significant meaning has determination of the zone in the goaf with caving, in which necessary conditions for occurence of endogenous fire are fulfilled. In the real conditions determination of such a zone is practically impossible. The main aim of the analysis was to determine the impact of type of the roof rocks forming the goaf on the location and range of endogenous fires particular hazard zone by in these goaf. For determined mining-geological conditions, the critical value of velocity of airflow and oxygen concentration in goaf, conditioning initiation of coal oxidation process were determined.

Mining toward the year 2000

International Nuclear Information System (INIS)

Anon.

1981-01-01

Mining in South Africa to this present day has not been a case of dramatic development, rather a steady technical progress, assisted by a rising product market price. Prominent men in the mining industry look at the future in terms of that logical development. Coverage is given to gold, mine unionization, coal, rock bursts, ventilation, uranium and ocean mining

Prairie of mine(s) : cultural reclamation of the Estevan/Bienfait Coalfields

Energy Technology Data Exchange (ETDEWEB)

Baxter, S.

2010-07-01

A cultural reclamation project was launched in the Bienfait region of southern Saskatchewan where lignite mining has been ongoing since the 1800s. Evidence of 5 surface mines, 2 power stations and thousands of acres of spoil piles remain at the abandoned site. The region also comprises 140 abandoned underground mines and 4 mined-out townsites. The project introduced cultural reclamation into the role of landscape architecture, specifically in the planning and design of reclaimed mining lands. At the present time, the reclamation of post-extractive sites is limited to focusing almost exclusively on ecological factors, but failing to recognize the people and the industrial processes that actively transformed the landscape can disengage people from their past. The project concludes with a proposed master plan in addition to a few site-specific interventions that interrogate and explore the role of experiential, cultural, and historical elements in the reclamation of a site. In doing so, awareness is created about the ways in which various landscapes are manipulated every day in order for people to live in greater comfort.

Coal mine subsidence

International Nuclear Information System (INIS)

Rahall, N.J.

1991-05-01

This paper examines the efficacy of the Department of the Interior's Office of Surface Mining Reclamation and Enforcement's (OSMRE) efforts to implement the federally assisted coal mine subsidence insurance program. Coal mine subsidence, a gradual settling of the earth's surface above an underground mine, can damage nearby land and property. To help protect property owners from subsidence-related damage, the Congress passed legislation in 1984 authorizing OSMRE to make grants of up to $3 million to each state to help the states establish self-sustaining, state-administered insurance programs. Of the 21 eligible states, six Colorado, Indiana, Kentucky, Ohio, West Virginia, and Wyoming applied for grants. This paper reviews the efforts of these six states to develop self-sustaining insurance programs and assessed OSMRE's oversight of those efforts

Safety Research and Experimental Coal Mines

Data.gov (United States)

Federal Laboratory Consortium — Safety Research and Experimental Coal MinesLocation: Pittsburgh SiteThe Safety Research Coal Mine and Experimental Mine complex is a multi-purpose underground mine...

The accident analysis of mobile mine machinery in Indian opencast coal mines.

Science.gov (United States)

Kumar, R; Ghosh, A K

2014-01-01

This paper presents the analysis of large mining machinery related accidents in Indian opencast coal mines. The trends of coal production, share of mining methods in production, machinery deployment in open cast mines, size and population of machinery, accidents due to machinery, types and causes of accidents have been analysed from the year 1995 to 2008. The scrutiny of accidents during this period reveals that most of the responsible factors are machine reversal, haul road design, human fault, operator's fault, machine fault, visibility and dump design. Considering the types of machines, namely, dumpers, excavators, dozers and loaders together the maximum number of fatal accidents has been caused by operator's faults and human faults jointly during the period from 1995 to 2008. The novel finding of this analysis is that large machines with state-of-the-art safety system did not reduce the fatal accidents in Indian opencast coal mines.

Mine Waste Disposal and Managements

Energy Technology Data Exchange (ETDEWEB)

Cheong, Young-Wook; Min, Jeong-Sik; Kwon, Kwang-Soo [Korea Institute of Geology Mining and Materials, Taejon (KR)] (and others)

1999-12-01

This research project deals with: Analysis and characterization of mine waste piles or tailings impoundment abandoned in mining areas; Survey of mining environmental pollution from mine waste impounds; Modelling of pollutants in groundwater around tailings impoundment; Demonstration of acid rock drainage from coal mine waste rock piles and experiment of seeding on waste rock surface; Development of a liner using tailings. Most of mine wastes are deposited on natural ground without artificial liners and capping for preventing contamination of groundwater around mine waste piles or containments. In case of some mine waste piles or containments, pollutants have been released to the environment, and several constituents in drainage exceed the limit of discharge from landfill site. Metals found in drainage exist in exchangeable fraction in waste rock and tailings. This means that if when it rains to mine waste containments, mine wastes can be pollutant to the environment by release of acidity and metals. As a result of simulation for hydraulic potentials and groundwater flow paths within the tailings, the simulated travel paths correlated well with the observed contaminant distribution. The plum disperse, both longitudinal and transverse dimensions, with time. Therefore liner system is a very important component in tailings containment system. As experimental results of liner development using tailings, tailings mixed with some portion of resin or cement may be used for liner because tailings with some additives have a very low hydraulic conductivity. (author). 39 refs.

75 FR 20918 - High-Voltage Continuous Mining Machine Standard for Underground Coal Mines

Science.gov (United States)

2010-04-22

... DEPARTMENT OF LABOR Mine Safety and Health Administration 30 CFR Parts 18 and 75 RIN 1219-AB34 High-Voltage Continuous Mining Machine Standard for Underground Coal Mines Correction In rule document 2010-7309 beginning on page 17529 in the issue of Tuesday, April 6, 2010, make the following correction...

36 CFR 6.7 - Mining wastes.

Science.gov (United States)

2010-07-01

... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false Mining wastes. 6.7 Section 6... DISPOSAL SITES IN UNITS OF THE NATIONAL PARK SYSTEM § 6.7 Mining wastes. (a) Solid waste from mining includes but is not limited to mining overburden, mining byproducts, solid waste from the extraction...

Remediation of acid mine drainage from the Santa Fe tin mine, Bolivia

Science.gov (United States)

Calvo, Daniel; Zamora Echenique, Gerardo; Alfonso, Pura; Casado, Jordi; Trujillo, Elvys; Jiménez-Franco, Abigail; Garcia-Valles, Maite

2015-04-01

The Santa Fe mine, department of Oruro, is located in the Andean Tin belt, is exploited for tin, zinc, lead and silver. This in an underground mine mined up to the -108 level. Today it is only mined up to the -50 level. Under this level the table water covers the mine. Water reaches the surface with a very acidic composition, with a high content in potentially toxic elements. This water drains directly to the Santa Fe River and contribute to the pollution present in this river that directly affect to the aquatic communities. In addition, population of this area have problems in the supply of drinking water, so remediation by obtaining cleaning water is a priority for this area. This study presents a neutralization-precipitation treatment with lime to the acid water inside the mine. The ore mineralogy of the Santa Fe mined deposit consists mainly in cassiterite, pyrite, sphalerite, galena, arsenopyrite argentite and sulphosalts. The host mineral is mainly quartz, with a minor content in feldspars and tourmaline. Alteration minerals as alunite, goethite and pumbojarosite are abundant and indicate the occurrence of reactions that lead to the formation of acid mine drainage. The mean pH of water drained from the Santa Fe mine is 2.2 and chemical analyses show high contents in potentially toxic elements: 27-295 ppm Zn, 0.05-0.2 ppm Pb, 0.06-0.09 ppm Cd, 04-0.12 ppm Cu, 113-165 ppm Fe, 4 ppm Mn and 564-664 ppm S. As and Sb were under 0.5 ppm. A settler tank inside the mine was designed by means of seal a selected gallery to clean the mine water. The function of this gallery is to sediment the sludge resulting from the neutralization - precipitation treatment process to obtain a clear water overflow continuously to the outside. The neutralization tests indicate that 0.65g/L of lime and 2ml of flocculant should be added to neutralize water up to pH 6-7. A flow rate of 80 L /s was considered. After a geotechnical study, a chamber located in the mine was selected to locate

A technology map to facilitate the process of mine modernization throughout the mining cycle

OpenAIRE

Jacobs, J.; Webber-Youngman, R.C.W.

2017-01-01

It is vital for organizations and individual operations to have access to a platform with technology-related information to consider for further research and development. This paper presents a technology map that was created with the purpose of facilitating mine modernization through technological advancement throughout the mining lifecycle/cycle. To achieve this, a platform was created to represent the mining life-cycle that incorporates each of the mining phases, i.e. exploration, project e...

ENVIRONMENTAL MANAGEMENT OF MINE WATER, CONSIDERING EUROPEAN WATER LEGISLATION. CASE STUDY OF MEGALOPOLIS MINES

OpenAIRE

Dimitrakopoulos, D.; Vassiliou, E.; Tsangaratos, P.; Ilia, I.

2017-01-01

Mining activities causes many environmental problems to the surrounding areas, as other industrial activities do also. However mine water pollution, is considered a tough task to handle, as it requires specific regulations, quite distinct from those applicable to most other industrial processes. Even though there are several federal laws and regulations in Greece and in the European Union that influences the mining industry and mine water management, still certain factors complicates their im...

The pit ventilation features and the design principle of ventilation system in trackless mining uranium mine

International Nuclear Information System (INIS)

Deng Wenhui; Zhou Xinghuo; Li Xianjie

2001-01-01

According to the pit arrangement features of trackless mining uranium mine, based on the fundamental of radon permeation and control, and analysis of radon pollution characteristics and radon education, the design principle of ventilation system in trackless mining uranium mine has been raised

Mining Pribram in science and technology. Proceedings of Session R - Mechanization of mine operations

International Nuclear Information System (INIS)

Kolar, J.; Bernatik, O.

1987-01-01

The proceedings contain 30 papers of which two deal with uranium mine problems, viz.: ''Current and prospective orientation of mechanized driving of mines and underground infrastructures'' and ''The operation of rail-less mine mechanization in the Hamr area''. (J.B.)

URL Mining Using Agglomerative Clustering Algorithm

Directory of Open Access Journals (Sweden)

Chinmay R. Deshmukh

2015-02-01

Full Text Available Abstract The tremendous growth of the web world incorporates application of data mining techniques to the web logs. Data Mining and World Wide Web encompasses an important and active area of research. Web log mining is analysis of web log files with web pages sequences. Web mining is broadly classified as web content mining web usage mining and web structure mining. Web usage mining is a technique to discover usage patterns from Web data in order to understand and better serve the needs of Web-based applications. URL mining refers to a subclass of Web mining that helps us to investigate the details of a Uniform Resource Locator. URL mining can be advantageous in the fields of security and protection. The paper introduces a technique for mining a collection of user transactions with an Internet search engine to discover clusters of similar queries and similar URLs. The information we exploit is a clickthrough data each record consist of a users query to a search engine along with the URL which the user selected from among the candidates offered by search engine. By viewing this dataset as a bipartite graph with the vertices on one side corresponding to queries and on the other side to URLs one can apply an agglomerative clustering algorithm to the graphs vertices to identify related queries and URLs.

Service mining framework and application

CERN Document Server

Chang, Wei-Lun

2014-01-01

The shifting focus of service from the 1980s to 2000s has proved that IT not only lowers the cost of service but creates avenues to enhance and increase revenue through service. The new type of service, e-service, is mobile, flexible, interactive, and interchangeable. While service science provides an avenue for future service researches, the specific research areas from the IT perspective still need to be elaborated. This book introduces a novel concept-service mining-to address several research areas from technology, model, management, and application perspectives. Service mining is defined as "a systematical process including service discovery, service experience, service recovery, and service retention to discover unique patterns and exceptional values within the existing services." The goal of service mining is similar to data mining, text mining, or web mining, and aims to "detect something new" from the service pool. The major difference is the feature of service is quite distinct from the mining targe...

Mine-built ponds economically clear acid mine waters

Energy Technology Data Exchange (ETDEWEB)

Chironis, N P

1987-01-01

One of the by-products of surface mining is acid mine drainage. Traditional treatment of acid drainage is the addition of a base chemical such as sodium hydroxide, soda ash or lime to neutralize the water and allow metals, such as iron and manganese, to settle out. However researchers were intrigued by the idea of using home-made wetlands containing bogs of sphagnum moss to do the job naturally and more cheaply without the heavy application of chemicals. Such plants as cattails were found to be very effective. Aspects considered are: the wetlands affinity for acid water; the aid of algae and bacteria; building a wetland; and recommendations by the Bureau of Mines for constructing wetlands including flow capacity, pH goal, minerals removal, design criteria, plant materials, growing media, plant settling, nutrients, water level and flow control.

Radiological characterization of a uranium mine with no mining activity

International Nuclear Information System (INIS)

Lozano, J.C.; Vera Tome, F.; Gomez Escobar, V.; Blanco Rodriguez, P.

2000-01-01

We report a radiological study of a uranium mine located in Extremadura, in the south-west of Spain, in which mining work had ceased. One interest in the work is that the results can be used as a reference for the future evaluation of the effects produced by the restoration program. The radiological parameters selected to estimate the impact of the inactive mine were: 222 Rn in air and water, 222 Rn exhalation, effective 226 Ra in soils and sediments, and natural uranium and 226 Ra in water. Chemical analyses of water samples and measurements of meteorological variables were also made. Average values of these radiological parameters are presented. We characterize the zone radiologically and estimate the influence of the mine on the basis of some of these parameters, while others are used to reflect the status of the installation, information which could be very useful in the near future when restoration is complete

Exploration on feasibility of mining under pressure in depth at uranium mine No.711

International Nuclear Information System (INIS)

Xie Jun

1993-01-01

Through the analysis of mining practice in the mine No.711, it was found that it was technically feasible to mine the depth of the deposit suffering plenty underground hot water under pressure, and good economic benefits and environmental effects were obtained

WIRELESS MINE WIDE TELECOMMUNICATIONS TECHNOLOGY

International Nuclear Information System (INIS)

Zvi H. Meiksin

2002-01-01

Two industrial prototype units for through-the-earth wireless communication were constructed and tested. Preparation for a temporary installation in NIOSH's Lake Lynn mine for the through-the-earth and the in-mine system were completed. Progress was made in the programming of the in-mine system to provide data communication. Work has begun to implement a wireless interface between equipment controllers and our in-mine system

Mining software specifications methodologies and applications

CERN Document Server

Lo, David

2011-01-01

An emerging topic in software engineering and data mining, specification mining tackles software maintenance and reliability issues that cost economies billions of dollars each year. The first unified reference on the subject, Mining Software Specifications: Methodologies and Applications describes recent approaches for mining specifications of software systems. Experts in the field illustrate how to apply state-of-the-art data mining and machine learning techniques to address software engineering concerns. In the first set of chapters, the book introduces a number of studies on mining finite

False alarms and mine seismicity: An example from the Gentry Mountain mining region, Utah

International Nuclear Information System (INIS)

Taylor, S.R.

1992-01-01

Mining regions are a cause of concern for monitoring of nuclear test ban treaties because they present the opportunity for clandestine nuclear tests (i.e. decoupled explosions). Mining operations are often characterized by high seismicity rates and can provide the cover for excavating voids for decoupling. Chemical explosions (seemingly as part of normal mining activities) can be used to complicate the signals from a simultaneous decoupled nuclear explosion. Thus, most concern about mines has dealt with the issue of missed violations to a test ban treaty. In this study, we raise the diplomatic concern of false alarms associated with mining activities. Numerous reports and papers have been published about anomalous seismicity associated with mining activities. As part of a large discrimination study in the western US (Taylor et al., 1989), we had one earthquake that was consistently classified as an explosion. The magnitude 3.5 disturbance occurred on May 14, 1981 and was conspicuous in its lack of Love waves, relative lack of high- frequency energy, low Lg/Pg ratio, and high m b - M s . A moment-tensor solution by Patton and Zandt (1991) indicated the event had a large implosional component. The event occurred in the Gentry Mountain coal mining region in the eastern Wasatch Plateau, Utah. Using a simple source representation, we modeled the event as a tabular excavation collapse that occurred as a result of normal mining activities. This study raises the importance of having a good catalogue of seismic data and information about mining activities from potential proliferant nations

Granular-relational data mining how to mine relational data in the paradigm of granular computing ?

CERN Document Server

Hońko, Piotr

2017-01-01

This book provides two general granular computing approaches to mining relational data, the first of which uses abstract descriptions of relational objects to build their granular representation, while the second extends existing granular data mining solutions to a relational case. Both approaches make it possible to perform and improve popular data mining tasks such as classification, clustering, and association discovery. How can different relational data mining tasks best be unified? How can the construction process of relational patterns be simplified? How can richer knowledge from relational data be discovered? All these questions can be answered in the same way: by mining relational data in the paradigm of granular computing! This book will allow readers with previous experience in the field of relational data mining to discover the many benefits of its granular perspective. In turn, those readers familiar with the paradigm of granular computing will find valuable insights on its application to mining r...

Data Mining Aplications in Livestock

Directory of Open Access Journals (Sweden)

Feyza ALEV ÇETİN

2016-03-01

Full Text Available Data mining provides discovering the required and applicable knowledge from very large amounts of information collected in one centre. Data mining has been used in the information industry and society. Although many methods of data mining has been used, these techniques has been remarkable in animal husbandry in recent years. For the solution of complex problems in animal husbandry many methods were discussed and developed. Brief information on data mining techniques such as k-means approach, k-nearest neighbor approach, multivariate adaptive regression function (MARS, naive Bayesian classifiers (NBC, artificial neural networks (ANN, support vector machines (SVM, decision trees are given in the study. Some data mining methods are presented and examples of the application of data mining in the field of animal husbandry in the world are provided with this study.

Data mining for bioinformatics applications

CERN Document Server

Zengyou, He

2015-01-01

Data Mining for Bioinformatics Applications provides valuable information on the data mining methods have been widely used for solving real bioinformatics problems, including problem definition, data collection, data preprocessing, modeling, and validation. The text uses an example-based method to illustrate how to apply data mining techniques to solve real bioinformatics problems, containing 45 bioinformatics problems that have been investigated in recent research. For each example, the entire data mining process is described, ranging from data preprocessing to modeling and result validation. Provides valuable information on the data mining methods have been widely used for solving real bioinformatics problems Uses an example-based method to illustrate how to apply data mining techniques to solve real bioinformatics problems Contains 45 bioinformatics problems that have been investigated in recent research.

Single-section mines carve out a market

International Nuclear Information System (INIS)

Sanda, A.P.

1991-01-01

In the Appalachian states of Pennsylvania, West Virginia, Kentucky and Virginia there are large operations whose complexes are an agglomeration of one and two-section mines; large operators whose own mines are augmented by small contractors; small contractors whose one-section mines collectively make them large operators within this genre; and independent, sole-owner operators of single-contract mines. Finally, there is the totally independent operator who negotiates his own leases, mines his own coal and searches for his own markets. The article profiles 6 single section mines. Mines were chosen on criteria including: the equipment in use; obtaining a representive sample of the states with many small coal mines particularly West Virginia, Virginia and Kentucky; the divergence of operators and situations. The mines chosen were: Elk Run; Kinney Branch Coal Co. No. 5 mine; A ampersand G No. 1 mine; Dotson and Rife Coal Co.; Bullion Hollow Coal Co.; and Bruce Coal. The article includes production rates and mine specifications. 1 tab

Mine waste acidic potential and distribution of antimony and arsenic in waters of the Xikuangshan mine, China

International Nuclear Information System (INIS)

Zhou, Jianwei; Nyirenda, Mathews T.; Xie, Lina; Li, Yi; Zhou, Baolong; Zhu, Yue; Liu, Huilin

2017-01-01

The Xikuangshan (XKS) mine in China has vast quantities of waste material and reported antimony (Sb) and arsenic (As) contamination of water in the mine area. This study estimated the potential of acid mine drainage (AMD) generation by waste material at XKS mine by using paste pH, acid base accounting and net acid generation geochemical static tests. Distribution of Sb and As in surface and groundwater in relation to mine waste AMD producing potential was also investigated. Thirty four (34) water samples and representative samples of three mine wastes from different periods (fresh, 10 and 50 years) were collected for this study: waste rock, smelting slag and tailings. The AMD prediction shows that waste rock (from 10 year period) is acid producing while the fresh mine waste had alkaline paste pH indicating the presence of reactive carbonates. Hence AMD generation may have occurred after a long time due to dissolution of carbonates. Water analysis found Sb with higher concentration than As with means of 3.74 mg/L and 0.19 mg/L respectively. Highest Sb and As concentrations were observed in the North mine along the water flow path from waste heaps and tailing pond; Mine water in the South mine also had elevated Sb and As concentrations. Mining activities at the XKS mine have accelerated Sb and As releases because of the disturbed natural equilibrium. Proper mine waste management and collection and treatment of outflow from the waste rock heaps and tailing ponds seem to be a promising mitigation options. - Highlights: • High levels of Sb and As were detected in alkaline water at Xikuangshan mine. • Static test showed that mine waste aged over 10 years was acid generating. • Mine waste influenced the high concentration of Sb and As in water. • The Sb/As ratios in water favored Sb because of high Sb content in the ore body.

Data Mining Mining Data: MSHA Enforcement Efforts, Underground Coal Mine Safety, and New Health Implications

OpenAIRE

Kniesner, Thomas J.; Leeth, John D.

2003-01-01

Studies of industrial safety regulations, OSHA in particular, often find little effect on worker safety. Critics of the regulatory approach argue that safety standards have little to do with industrial injuries, and defenders of the regulatory approach cite infrequent inspections and low penalties for violating safety standards. We use recently assembled data from the Mine Safety and Health Administration (MSHA) concerning underground coal mine production, safety regulatory activities, and wo...

Geomorphological and hydrological transformation of the landscape due to mining activity in the mining area Bana Dolina

International Nuclear Information System (INIS)

Balga, J.; Hroncova, E.

2010-01-01

After more than 150 year history of mining activity in the brown coal mining area Bana Dolina have been produced a range of anthropogenic forms of relief. For reasons of underground coal mining to make interventions in the hydrographic network. Significant changes due to surface mining of coal seams should result in subsidence basins of different sizes, damage to buildings and roads. Mining activity was influenced by agricultural and forestry fund, gardening settlements. All these factors have contributed to the change in relief of the surrounding area. This study aims to research the effects of the largest mining Bana Dolina mining area reflecting the structure of land area. (authors)

Study of Coal Burst Source Locations in the Velenje Colliery

Directory of Open Access Journals (Sweden)

Goran Vižintin

2016-06-01

Full Text Available The Velenje coal mine (VCM is situated on the largest Slovenian coal deposit and in one of the thickest layers of coal known in the world. The thickness of the coal layer causes problems for the efficiency of extraction, since the majority of mining operations is within the coal layer. The selected longwall coal mining method with specific geometry, increasing depth of excavations, changes in stress state and naturally given geomechanical properties of rocks induce seismic events. Induced seismic events can be caused by caving processes, blasting or bursts of coal or the surrounding rock. For 2.5D visualization, data of excavations, ash content and calorific value of coal samples, hanging wall and footwall occurrence, subsidence of the surface and coal burst source locations were collected. Data and interpolation methods available in software package Surfer®12 were statistically analyzed and a Kriging (KRG interpolation method was chosen. As a result 2.5D visualizations of coal bursts source locations with geomechanical properties of coal samples taken at different depth in the coal seam in the VCM were made with data-visualization packages Surfer®12 and Voxler®3.

Report on a commercialization fundamental investigation (in Batulicin Area, Indonesia) in relation to FY 1997 investigations on geological structures in overseas countries; 1997 nendo kaigai chishitsu kozo nado chosa ni kakawaru kigyoka kiso chosa (Indonesia Batulicin chiku) hokokusho

Energy Technology Data Exchange (ETDEWEB)

NONE

1998-03-01

A fundamental coal mine development investigation was carried out in Batulicin Area, Kalimantan, the Republic of Indonesia. The investigation included ground surface surveys, preparation of topographical maps and geological maps, trial drilling investigation, physical logging, chemical analysis, and infrastructure investigation. The trial drilling investigation was intended to identify the existence conditions of coal beds and coal quality, and was performed by forming grids with about 500-meter interval, and using 21 trial drillings to depths of 104 to 240 meters for a total drilling length of 3463 meters. The physical logging included electric logging, radioactivity logging and pore size logging, and the trial drilling cores were subjected to chemical analysis. For infrastructures, investigations were carried out on necessity of modifying existing roads, privilege relationship, the current status of barge loading points, water depths, and land acquisition. The result of the investigation revealed that minable coal quantity in underground mining of the coal bed B would be 13.189 million tons, and that annual production of original coal at 733,000 tons would be possible by adopting a long-wall type mechanized coal mining system. 14 refs., 99 figs., 25 tabs.

Remote Sensing based multi-temporal observation of North Korea mining activities : A case study of Rakyeon mine

Science.gov (United States)

Lim, J. H.; Yu, J.; Koh, S. M.; Lee, G.

2017-12-01

Mining is a major industrial business of North Korea accounting for significant portion of an export for North Korean economy. However, due to its veiled political system, details of mining activities of North Korea is rarely known. This study investigated mining activities of Rakyeon Au-Ag mine, North Korea based on remote sensing based multi-temporal observation. To monitor the mining activities, CORONA data acquired in 1960s and 1970s, SPOT and Landsat data acquired in 1980s and 1990s and KOMPSAT-2 data acquired in 2010s are utilized. The results show that mining activities of Rakyeon mine continuously carried out for the observation period expanding tailing areas of the mine. However, its expanding rate varies between the period related to North Korea's economic and political situations.

Abandoned Smolník mine (Slovakia – a catchment area affected by mining activities

Directory of Open Access Journals (Sweden)

Lintnerová, Otília

2008-06-01

Full Text Available Smolník is a historical Cu-mining area that was exploited from the 14th century to 1990. The Smolník mine was definitively closed and flooded in 1990–1994. Acid mine drainage discharging from the flooded mine (pH = 3.83, Fe = 542 mg/l, SO42– = 3642 mg/l, Cu = 1880 µg/l, Zn = 9599 µg/l, As = 108 mg/l acidified and contaminated the Smolník Creek water, which transported pollution into the Hnilec River catchment. The Smolník mine waste area has been used as a model area to document pollution of waters, stream sediments, and soils by metals and other toxic elements. Major goals of this complex study were to document creek water transport of the main pollutants (Fe, sulphates, Cu, Al, As, etc. in the form of suspended solids, to investigate elements mobility in common mine waste (rock and processing waste heaps and tailing impoundment and in the soil on the basis of neutralization and leach experiments. Different methodologies and techniques for sampling and chemical and mineralogical characterization of samples were used and checked to evaluate environmental risk of this abandoned mine area.

Open Pit Mining & The Cost of Water Potential Opportunities Towards Sustainable Mining

OpenAIRE

Sébastien J.R. Fortin

2015-01-01

Mining operations require vast quantities of water to run ore processing facilities and thus have a responsibility to manage this critical resource. Operations are often located in areas of limited water supply, which may create a competitive climate for water consumption. Make-up water for mineral processing can represent a significant portion of production cost for mining companies. While necessary for mining, water in open pits is problematic for extraction activities and leads to increase...

WIRELESS MINE WIDE TELECOMMUNICATIONS TECHNOLOGY

Energy Technology Data Exchange (ETDEWEB)

Zvi H. Meiksin

2002-04-01

Two industrial prototype units for through-the-earth wireless communication were constructed and tested. Preparation for a temporary installation in NIOSH's Lake Lynn mine for the through-the-earth and the in-mine system were completed. Progress was made in the programming of the in-mine system to provide data communication. Work has begun to implement a wireless interface between equipment controllers and our in-mine system.

Application of analytic hierarchy process in mine environmental assesment-take Fuxin mines as example

International Nuclear Information System (INIS)

Kong Zhizhao; Jiang Xue; Dong Shuangfa; Zhao Zhao

2012-01-01

We taking mine environmental assessment work by analytic hierarchy process on the basis of results of remote sensing investigation in Fuxin Mines. Putting forward an assessing system consist of index, method and levels. This system makes the levels by weight percent calculated by judging matrixes. Taking Hebei Mines as an example test the system. It shows that the result by the system is credible and is reasonable. This provides a significant data for the second-mines-plan of Liaoning Province. (authors)

Data mining theories, algorithms, and examples

CERN Document Server

Ye, Nong

2013-01-01

AN OVERVIEW OF DATA MINING METHODOLOGIESIntroduction to data mining methodologiesMETHODOLOGIES FOR MINING CLASSIFICATION AND PREDICTION PATTERNSRegression modelsBayes classifiersDecision treesMulti-layer feedforward artificial neural networksSupport vector machinesSupervised clusteringMETHODOLOGIES FOR MINING CLUSTERING AND ASSOCIATION PATTERNSHierarchical clusteringPartitional clusteringSelf-organized mapProbability distribution estimationAssociation rulesBayesian networksMETHODOLOGIES FOR MINING DATA REDUCTION PATTERNSPrincipal components analysisMulti-dimensional scalingLatent variable anal

Data mining for service

CERN Document Server

2014-01-01

Virtually all nontrivial and modern service related problems and systems involve data volumes and types that clearly fall into what is presently meant as "big data", that is, are huge, heterogeneous, complex, distributed, etc. Data mining is a series of processes which include collecting and accumulating data, modeling phenomena, and discovering new information, and it is one of the most important steps to scientific analysis of the processes of services.  Data mining application in services requires a thorough understanding of the characteristics of each service and knowledge of the compatibility of data mining technology within each particular service, rather than knowledge only in calculation speed and prediction accuracy. Varied examples of services provided in this book will help readers understand the relation between services and data mining technology. This book is intended to stimulate interest among researchers and practitioners in the relation between data mining technology and its application to ...