Results 1 - 10 of 1887
Results 1 - 10 of 1887. Search took: 0.022 seconds
|Sort by: date | relevance|
[en] This article presents the general flow chart of stripping, mining, processing and handling of coal at Maamba Collieries. Major sources of environmental degradation starting from the Open Pit, Coal Preparation Plant(CCP), Aerial Ropewayup to the Screening Plantand dispatch facilities located some eleven kilometres away at Masuku Rail Terminalare pointed out. Past and on-going efforts by Maamba Collieries at ameliorating and, where feasible, mitigating of adverse environmental impact of mining, processing and handling of coal as well as limitations of these measures as applied at Maamba are presented and discussed. (author)
[en] Due to the inability of the single line of sight D-InSAR to monitor the three-dimensional deformation of the surface, the conventional methods are unable to obtain the prediction parameters (probability integral parameters) of surface subsidence in coal mining. In this paper, a calculation method of simulated annealing (SA) for probability integral parameters based on single line of sight D-InSAR is proposed. Firstly, the method predicts the subsidence, the horizontal movement in the north–south direction and the horizontal movement in the east–west direction of the target pixel by using the probability integral method. Based on the projection relationship between the three-dimensional deformation and the LOS deformation, the predicted movement and deformation of the target pixel in LOS direction () are calculated. Using the measured movement and deformation of the target pixel in LOS direction (), the residuals of the target pixel are calculated () and the error function of the parameter is constructed (). Then based on the criteria (), all the probability integral parameters are obtained accurately by the SA method. The accuracy and robustness of the proposed method are verified by simulation experiments. At last, the predicted parameters of mining subsidence in 9310 working face of Nantun Coal Mine are calculated by this method, and the characteristics of probability integral parameters are analyzed.
[en] We would like to test the concept that induced seismicity prior to relatively large mining tremor (ML > 2.5, E > 106J) can be inferred from the cumulative Benioff strain release (BSR) as power law time-to-failure before the strong event. This study presents the application of accelerating BSR prior to a large earthquake, widely used in natural seismicity, for analysis of this phenomenon in induced seismicity. The Benioff strain release is quantified as accelerated releases of cumulative (square root sum) of seismic energy in the time series. During the study, five sequences were extracted from the seismic catalogues from two Polish hard coal mines: exhausted Bobrek Mine (data form the IS-EPOS Platform) and from a mine belonging to the Polish Mining Group. Next, a search radius was used to select precursory events and to indicate the type of processes occurring in the coal seam and its vicinity. The fitted power law of cumulative Benioff strain release showed changes of m-parameter. If the value of m was lower than 1.0, the process was regarded as an accelerating-like and if m was higher than 1.0—as a quiescence-like. The investigation of m-parameter vs. the search radius showed the general behaviour of the rock mass in the studied areas and allowed to evaluate the relationship between the critical radius and magnitude of the target event. The obtained scaling relation log(Rc) ~ 0.35 ML is similar to these reported by other authors who analysed natural seismicity which might suggest that the scaling relation works in a wide range of magnitudes.
[en] In recent years, environment concerns have attracted a great deal of attention worldwide. It has been acknowledged that the danger of environmental degradation is threatening the very existence of mining industry. Simultaneously ecological awareness and sensitivity have spawned a new commitment, on part of the industry, towards the environment. Pertinent to note in this paper is that an economic model has also been developed, which describes the exploitation of Lignite and its interaction with rest of the economy, including the environmental consequences, to ensure that the damage caused to the environment and society is contained within acceptable limits. This model has been implemented as a workable and viable alternative for environment protection in a lignite mine in India. 5 refs
[en] The French Society Miniere et Metallurgique de Panarroya mining railway, 241 km long, was the second largest private narrow gauge railway in Spain. Located in the inland. linked the coal and galena mines with foundries and also with the national railroads grid, to transport the minerals to national and foreign markets. (Author)
[en] Small scale coal mines (SCMs) have played an important role in China’s energy supply. At the same time, they also suffer from many social, economic, environmental, and safety problems. The Chinese government has made considerable efforts to strengthen the safety regulation of the coal mining industry. Yet, few of these efforts have proven to be very effective. This paper analyzes the interests and influences of key stakeholders in the safety regulation of SCMs, which includes the safety regulator, the local government, the mine owner, and mineworkers. We argue that the effective regulation of coal mine safety must both engage and empower mineworkers. - Highlights: ► Small scale coal mines have played an important role in China's energy supply. ► We analyze the interests and influences of key stakeholders in the safety regulation of small coal mines. ► The mineworkers have the strongest interest but least influence. ► An effective regulation must engage the mineworkers, organize, and empower them.
[en] Small-scale mining for coal is practiced all over the world. But major proportions of these mines are located in developing countries in Asia. China, India and Pakistan are the main producers of coal from small- scale mines. Due to prevailing poor safety conditions in these mines, a large number of workers receive injuries ranging from minor to fatal. Gas explosions/outbursts, roof falls, material handling, etc. are the main causes of majority of accidents occurring in small-scale mines. In China, thousands of workers are killed due to gas explosions/outbursts every year. Lack of financial resources, inadequate education and training of workers, contractual labour systems and lack of commitment to improve safety and health are the reasons that mainly contribute to the poor safety performance in this sector of mining. (author)
[en] Johannes Rau (SPD), the Prime Minister of North-Rhine Westphalia, and Michael Vesper, member of the Greens and his opposite number in the coalition negotiations, demonstrate placability. But on the subject of Garzweiler II, opinions are divided in the red-and-green coalition talks: while the party 'Buendnis 90/Die Gruenen' are uncompromising about abandoning Europe's largest brown-coal open-pit mining project, the SPD still sticks to it. (orig.)
[de]Nordrhein-Westfalens Ministerpaesident Johannes Rau (SPD) und der gruene Verhandlungspartner Michael Vesper zeigen sich versoehnlich. Doch in den rot-gruenen Koalitionsgespraechen scheiden sich beim Thema Garzweiler II die Geister: Waehrend die Buendnisgruenen Europas groesstes Braunkohletagebau-Projekt kompromisslos kippen wollen, steht die SPD nach wie vor dazu. (orig.)
[en] Lost-time accidents frequently occur in underground coal mining, which result in a substantial amount of lost workdays. In order to evaluate injury risks for the underground mining industry in Pakistan, two years record of lost time accidents were collected and analysed. Risk indices were computed for different variables, such as cause of accidents; age and job of the injured person; place of accidents; and part of the body injured. These indices incorporate information that has not been used in traditional accident analysis. Fall of ground type accidents were the major cause followed by haulage and transport. More than 50 % of accidents occurred at or Near the working faces and coal cutters/ face workers were found to be at a higher risk as compared to all other job categories. Injuries to hand and foot for all group of workers were comparatively higher than those to all other parts of the body; Workers in the age group of (21-30) years were involved in the majority of the lost time accidents. Regular and systematic analysis of lost time accidents should be made which may be helpful in reducing the frequency and severity of these accidents. (author)