It is not an exact science and in the choice of a method each varying factor has a certain weight, which, in many cases, experience alone can determine. Types of mining methods coal mining methods youtube. Because dust sampling has so many pitfalls, a chapter on methods used to sample dust is included. The actual difference between surface and underground mining. Surface and underground coal mining are broad activities that incorporate numerous variations in equipment and methods, and the choice of which method to use in extracting a coal seam depends on many technological, economic, and social factors. Two main methods of underground mining are practiced in pennsylvania. This method is used to recover resources in open stopes. This includes underground coal and hardrock mines, as well as surface mines, stone mines, and hardrock tunnels. Generally used for seams that are relatively flat or gently dipping. Underground mining methods and technology 1st edition isbn. Because deposits in sedimentary rocks are commonly layered and relatively less hard, the mining methods used differ from those used to mine deposits in igneous or metamorphic rocks see underground mining.
Longwall mining and roomandpillar mining are the two basic methods of mining coal underground, with roomandpillar being the traditional method in the. Coal and oil sands mines mining methods 14 coal and tar sands operations typically involve moving large amounts of waste often called overburdento gain access to the economic mineral. Recognised standard 12 place change mining operations in underground coal mines, department of natural resources and mines, 2015 1. Disposal and utilization of mineral wastes as a mine backfill s. An underground mine consists of the portals entrance and exits to the mines, mains, submains, panels, and working faces. Opencast coal mining recovers a greater proportion of the coal deposit than underground methods, as more of the coal seams in the strata may be exploited. When coal seams are near the surface, it may be economical to extract the coal using open cut also referred to as open cast, open pit, mountaintop removal or strip mining methods. Increasing mechanization has resulted in an increasing production in the amount of the fine coal. Geological and geotechnical aspects of underground coal. Mining techniques can be divided into two common excavation types. Underground soft rock mining is a group of underground mining techniques used to extract coal, oil shale, potash and other minerals or geological materials from sedimentary soft rocks.
Underground mining methods usually leave a significant portion of the coal reserve in the ground, some under ground mines recover only 30 to 50 percent of the. The subsequent chapters describe dust control methods for different kinds of mines and mining equipment. Longwall mining is an automated form of underground coal mining characterized by high recovery and extraction rates, feasible only in relatively flatlying, thick, and uniform coal beds. Ataei synopsis mining method selection is the first and most important problem in mine design. Water is collected at the lowest point in the open pit or underground mine, then pumped to surface. The panels are the working sections of the production operation. It set of longwall mining equipment consists of a coal shear er mounted on convey or operating. In any discussion of methods of underground mining comparison, one is repeatedly confronted with the difficulty of dealing with so many variable conditions. Underground mining involves opening one or more portals or shafts into the earth that follow or intercept coal seams that are too deep for surface mining methods. Pdf underground mining methods download full pdf book. Underground mining is usually by the roomandpillar mining or longwall mining method. In underground coal mining, the working environment is completely enclosed by the geologic medium, which consists of the coal seam and the overlying and underlying strata.
In this selection some of the parameters such as geological and geotechnical properties, economic parameters and geographical factors are involved. Both longwall and roomandpillar mining methods were utilized with the longwall method being the predominant type. Underground coal mining methods to abate water pollution. Surface mining methods and underground mining method. Underground mining methods and technology, volume 1 1st edition. It is probable that total extraction using longwall will be the correct choice of mining method. Mining method selection by multiple criteria decision making tools by m. Types of underground mining and their applications youtube. Types of underground mining and their applications duration. In the method of secondary extraction known as longwall mining a relatively long mining face typically in the range 100 to 300m but may be longer is created by driving a roadway at right angles between two roadways that form the sides of the longwall block, with one rib of this new roadway forming the longwall face. Coal producers the largest coal producing countries are not confined to one region the top five hard coal. Among them, caving and slow caving methods could not control the goaf roof. In this selective mining method, the void created by mining is backfilled with a.
More than 40 chapters covering such underground mining topics as sampling, planning, reserve analysis, cost calculations, various methods of support, block and panel caving, and sublevel caving make up this comprehensive text. Schematic diagram of an underground coal mine, showing surface facilities, access shaft, and the roomandpillar and longwall mining methods. The indian coal industry is the worlds third largest in terms of production and fourth largest in terms of. Figure f1 schematic of a roomandpillar coal mine section. Exploring abandoned mines and unusual places 1,667,926 views. These are the methods techniques employed when the depth of the deposit,the stripping ratio of the overburden to ore,or both becomes excessive to surface exploitation. Risk rate values are derived, and ignition source, methods of fire detection and suppression, and other variables are examined. Longwall mining is a form of underground coal mining where a long wall of coal is mined in a single slice.
Eagle mountain is part of the fording river operations in southeastern british columbia. Designs for coal, gold and diamond open pits are very similar. Advances in longwall mining method have made this system more economically attractive because of its efficiency and production potential. Underground coal mines of centerville, iowa and vicinity. Advancements in technology primarily hydraulics and explosives and expansion of mining activities in the west particularly in the prb, have shifted mining trends from underground to surface production over the past 40 years. Longwall mining and roomandpillar mining are the two basic methods of mining coal underground, with roomandpillar being the traditional method in the united states. The current methods must be judged on the economic factors and their advantages and disadvantages. Both methods are well suited to extracting the relatively flat coalbeds or coal seams typical of the united states.
Past coal mining practice left much coal in the ground as pillars that are difficult to recover. Longwall mining is a highly mechaniz ed underground mining sys tem for mining coal. An underground mine consists of the portals entrance and exits to the mines, mains. It consists of selected material from the outofprint industry standard, underground mining methods handbook. They prove particularly useful when their results are used for comparison with the results of observations under. Monitoring and sampling approaches to assess underground coal mine dust exposures compares the monitoring technologies and sampling protocols currently used or required by the united states, and in similarly industrialized countries for the control of rcmd exposure in underground coal mines. This handbook on surface strip coal mining serves as a general introduction to the subject of mining, specifically surface strip coal mining. A highpowered cutting machine the shearer is passed across the exposed face of coal, shearing away broken coal, which is continuously hauled away by a floor.
However, where profit is sensitive to the cost of extraction of water, there are often innovations, notably in the coal mining environment. Annual coal reports energy information administration. Underground mining methods and applications production headframe hans hamrin 1. A longwall miner shearing coal at the face of a coal seam. Coal mine safety achievements in the usa and the contribution. As can be seen, surface mining is much more advantageous than its counterpart. Pdf mining methods underground mining mayra garcia. The first step in selecting the most appropriate mining method is to compare the economic efficiency of extraction of the deposit by surface and underground mining methods. The contribution of niosh research includes products for prevention and survival of mine fires, methane control measures, design procedure for underground coal mines, methods for excavation surface controls, methods and procedures for blasting, laser usage in underground mines and prevention of.
The high productivity being achieved by longwall mining demonstrates its potential for being a substantial segment of underground coal production. Mining method selection by multiple criteria decision making. Appendix funderground coal mining methods and engineering dust controls. Information circular 9465 centers for disease control and. In underground coal mining, the working environment is completely enclosed by the g eologic medium, which consists of the coal seam and the ov erlying and. For each state, stand alone preparation plant hours are distributed across mining methods by the proportion of underground hours for. Damage repair underground bituminous coal mining operations pdf. Numerical modeling of open pit op to underground ug transition in coal mining 37 in recent years, with the development of computer science, numerical methods become more and more popular in solving problems of geoengineering. Ppt coal mining powerpoint presentation free to download. It is defined as a concentration of minerals that can be exploited and turned into a saleable product to generate a financially acceptable profit under existing economic conditions. Finally, this dissertation has illustrated the essential need for fundamental research if. Once the economic feasibility has been verified, the most appropriate mining methods must be selected according to the.
This method of mining was developed in the late 1960s to take advantage of the then recent development of suitable hydraulic longwall supports, coupled with the productivity and low capital cost of continuous miners and shuttle cars. Even in mines where the longwall method is the principal extraction method, the development of the mine and the longwall panels is accomplished by roomandpillar continuous mining. Both methods are well suited to extracting the relatively flat coalbeds or coal seams typical of. The contribution of niosh research includes products for prevention and survival of mine fires, methane control measures, design procedure for underground coal mines, methods for excavation surface controls, methods and procedures for blasting, laser usage in underground. The various methods of mining a coal seam can be classified under two headings, surface mining and underground mining. Numerous coal winning methods have been used on the mine during its four years of existence. Draglines which operate by removing the overburden, power shovels, large trucks in which transport overburden and coal, bucket wheel excavators, and. Underground mining methods while most mineral deposits can be mined by either surface or underground methods, some minerals can only be recovered in a hybrid manner, usually by initial extracted by open pit mining, followed by underground methods.
Coal production was exclusively from the mystic coal member of the labette shale pennsylvanian. Surface coal mining methods in australia intechopen. The various methods of mining a coal seam can be classified under two headings, surface. A manual of underground surveying civil engineering. Coal mining methods can be broadly divided into two types viz. Underground mining methods and equipment encyclopedia of life. A coal mining method that accounts f or less than 1% of deep coal production, shortwall involves the use of a continuous mining machine with mov eable roof supports, similar to longwall. Extensive underground mining occurred in the centerville area, appanoose county, iowa between 1850 and 1971. Criterion for the assessment of the cuttability of coal s. However, ever since the introduction of continuous miners in the late 1940s, roomandpillar continuous mining has been gaining ground over conventional roomandpillar mining. Pre sentday emphasis is on improving extraction per centage. In open pit mining, thick seams tens of meters are mined by traditional quarrying techniques. During the history of the mine, rapid variations in seam heights.
Most aspects of alternative cutting methods and cutting procedures have been referred to in the longwall section of the fundamentals of coal mining module of this web site and little can be added here. Although both crater and trough subsidence have occurred in. Geological and geotechnical aspects of underground coal mining methods within australia. Underground mining methods vary according to the site conditions, but all. Continuous mining also called bord and pillar is a mining system in which the mined material is extracted across a horizontal plane while leaving pillars of untouched material to support the. Underground mining is used for gold, platinum, zinc, lead, and increasingly, coal. Longwall mines produce more than 30 pct of all underground. Pdf coal mining methods underground mining longwall. Overall mining sequence of a typical surface coal mine in australia after westcott et al. Year ug production mm percentage underground surface production mm 1930. Apr 03, 2017 the first published, reference to the mining of coal in india dates back to the year 1774 in the raniganj coal field. Coal producers the largest coal producing countries are not confined to one region the top five hard coal producers are china, india, usa, indonesia and australia.
Longwall mining overview introduction underground coal. Comparison of designs for the dewatering of coal, gold and. This presentation explores the recent history and current trend of underground coal mining methods and production, planning and timing, and. Underground mining methods vary according to the site conditions, but all involve the removal of. Underground mining methods and technology, volume 1 1st. However, when an outcropping ore body stretches deep inside the earth, surface methods can be used to begin the mining operation, which then need to be continued further by underground. Jul 24, 2016 4100 feet underground in the massive, abandoned admiral aaron ward mine duration. Classification of underground mining methods mineral production in which all extracting operations are conducted beneath the ground. Underground mining methods are usually employed when the depth of the deposit andor the waste to ore ratio stripping ratio are too great to commence a surface operation. It is intended as handbook for engineers who are new to the field of mining engineering, or for students. Recognised standard 12 department of natural resources. With the use of a costing framework developed by the author incorporating new thinking to eliminate the shortcomings identified in the traditional costing approach, a comparison of two types of underground coal mining systems, viz. Depending on the mining method, a working section can have one or more working faces.