Pdfminer is a text extraction tool for pdf documents. In longwall mining, a panel of coal, typically around 150 to 300 metres wide, to 3500 metres long and 2 to 5 metres thick, is totally removed by longwall shearing machinery, which travels back and forth across the coalface. Longwall mines produce more than 30 pct of all underground coal, up from 5 pct just 15 years ago. Unfortunately, this book cant be printed from the openbook. The shortwall mining technique is similar to longwall mining but with shorter face lengths, ranging between 40 and 90 m, with the aim of controlling the ca. Jun 23, 1998 accordingly, the present invention provides an equipment for shortwall mining useful for extraction of pillars in underground coal mines, the equipment comprising a series of selfadvancing powered roof supports 1 being placed along pillars 2 under extraction. Mining is the extraction of valuable mineral or any other geological mineral from the earth the first mining operation started at the beginning of human civilization modern mining operation consists of prospecting of ore bodies, reserve estimation. Mining software free download mining top 4 download. Equipment for shortwall mining useful for extraction of. The continuous miner shears coal panels 150 200 feet wide and more than a half. Sales tax notification pdf 117 kb ksb is one of the worlds leading manufacturers of pumps and industrial valves ksb is the brand with the greatest technical expertise in pumps and valves. Introduction to longwall mining and subsidence ver2.
Hustulid, editor society of mining engineers 1982 1794 pages. Web miningis the use of data mining techniques to automatically discover and extract information from web documentsservices etzioni, 1996, cacm 3911 3 what is web mining. An object of the present invention is to provide a shortwall mining machine which can be operated without the need for operators to be on the face during winning operations. Another shortwall mining method was developed in the 1980s as a means of realising the benefits of longwall mining in a shallow seam, partial extraction application where there were considerable subsidence constraints under a residential area. Text mining with comprehensible output is tantamount to summarizing salient features from a large body of text, which is a subfield in its own right. Fifteen has been adapted for shortwall work either as undercutter or as overcutter, particular care having been taken to give it increased manoauvrability by the provision of special pulleys, and increased mobility by the addition of a tilting underframe. Shortwall involves the use of a continuous mining machine with mov eable roof supports, similar to longwall. Apr 08, 1980 this invention relates to shortwall mining machines for mining underground mineral seams, and in particular, but not exclusively for use in retreat mining of coal seams. General description shortwall mining is one of the newest mining methods to be introduced into the world coal industry. Ep0795680a1 shortwall mining equipment for extraction of. Other articles where shortwall method is discussed. Comparative shortwall and roomandpillar mining costs by green, larry e. Shortwall stoping versus sublevel longwall cavingretreat in.
In the shortwall mining method, the layout is similar to the longwall method except that the block of coal is not more than 100 metres wide. Shortwall mining a coal mining method that accounts for less than 1% of deep coal production, shortwall involves the use of a continuous mining machine with moveable roof supports, similar to longwall. Exploitation of developed coal mine pillars by shortwall. It includes an explanation of the different productskey components of a longwall mining.
Text mining and natural language processing text mining appears to embrace the whole of automatic natural language processing and, arguably. Shortwall mining of the developed bord and pillar workings would be a good option to overcome the. Underground coal mining technology coal mining the. Because deposits in sedimentary rocks are commonly layered and relatively less hard, the mining methods used differ from those used to mine deposits in.
This invention relates to an equipment for shortwall mining useful for extraction of pillars 2 in underground coal mines, which comprises a series of selfadvancing powered supports 1 being placed along the pillars under extraction, the pillars being located within a panel 3 which is being surrounded by barrier pillars 4. Optimization of the mine design factors is arguably the primary means for controlling interactions between operations. Hr no pillar remnants costs lower especially support costs personnel concentrated in one place training easier method to learn roof can be weak but might affect gateroads product coal is easy to wash, less fines ventilation is more concentrated good air upwind of shearer. Jan 01, 2005 read exploitation of developed coal mine pillars by shortwall mininga case example, international journal of rock mechanics and mining sciences on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Fundamental concepts and algorithms, by mohammed zaki and wagner meira jr, to be published by cambridge university press in 2014. As explained above, during the formation of coal and subsequent geologic activities, a coal seam may acquire mineral matter, veins of clay, bands of rock, and igneous intrusions. An armoured face conveyor 5 is fixed to said barrier pillars.
Shortwall vs conventional practice essay longwall, shortwall,depillaring introduction. 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. Furthermore, the slices are as much as three metres thick and are taken by a continuous miner. Starting from version 20191010, pdfminer supports python 3 only. Shortwall mining machine coal industry patents limited.
Alternative shortwall mining method gretley colliery. Scribd is the worlds largest social reading and publishing site. Coal mining methods underground coal mining methods are classified according to the method of ground control an excellent description of all methods is provided in samuel m. Kolyshkina and rooyen 2006 presented the results of an analysis that applied text mining on an insurance claims database. The mining rate includes the mining of both waste and ore. Longwall and shortwall mining methods and equipment.
This video provides a basic description of the longwall mining method for extracting coal underground. If you need to print pages from this book, we recommend downloading it as a pdf. A textbook of mining geology for the use of mining students. International journal of rock mechanics and mining sciences. American institute of mining engineers, 1973 as either room and pillar or longwall shortwall is considered a. As of today we have 78,789,783 ebooks for you to download for free. The travelway shall be located to follow the most direct and safe practical route to a.
Mining software free download mining top 4 download offers free software downloads for windows, mac, ios and android computers and mobile devices. The technique of shortwalling seems to have a number of origins, but it is generally agreed that it is an outgrowth of pillarandstall mining where timbering was employed as the primary means of roof support. A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. Mining is accomplished by driving substantially parallel entries into the trona formation approximately 100 to 200 feet apart, connecting the entries by at least one primary passage which thereby defines a trona panel, supporting the roof of the primary passage by movable roof supporting structures, and mining the exposed short face or wall of. Shortwall mining the pittsburg coal seam in northern western virginia. A typical section through a coal face is shown in fig. The shortwall mining technique is similar to longwall mining but with shorter face lengths, ranging between 40 and 90 m 5. In addition, during the process of mining, a portion of the roof and floor material may be taken along with the coal seam in order to create adequate working height for.
They applied text mining to a freeform claim comment field to derive concepts from the description. Exploitation of developed coal mine pillars by shortwall mininga case example. Suggested method shortwall mining shortwall mining is a production method in which excavation and loading are carried out by continuous miner under the protection of roof supports. The field of text mining is rapidly evolving, but at this time is not yet widely used in insurance. This book is an outgrowth of data mining courses at rpi and ufmg. Comparative shortwall and roomandpillar mining costs. Downloads stay up to date with the latest versions of our software and information available from this section of the website. Motivation opportunity the www is huge, widely distributed, global information service centre and, therefore, constitutes a rich source. 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. This report highlights the coal mining methods, their significances, issues of concern and the stages of using coal after mining. Mining engineering download as powerpoint presentation.