R Karl Zipf, W Marchewka, K Mohamed, J Addis, F Karnack
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.
{"title":"Tube bundle system: for monitoring of coal mine atmosphere.","authors":"R Karl Zipf, W Marchewka, K Mohamed, J Addis, F Karnack","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"65 5","pages":"57-63"},"PeriodicalIF":0.0,"publicationDate":"2013-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4545479/pdf/nihms706540.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33950552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In collaboration with Kennametal Inc. and Corry Rubber Corporation, the U.S. National Institute for Occupational Safety and Health (NIOSH) developed a drill bit isolator to address noise overexposures associated with roof bolting machines in underground coal mines. NIOSH laboratory studies confirmed that the drill bit isolator reduces noise during drilling. Field studies were needed to confirm that a noise reduction could be obtained under working conditions and that the device was sufficiently durable. This paper reports results of field tests of the device conducted at five underground coal mines. Noise reduction was assessed by comparing the operator's noise exposure during drilling with and without the drill bit isolator. Durability was assessed by recording the number of holes and total feet drilled with each bit isolator until either the test period ended or the device failed. The results from these tests showed that the device is an effective noise control in a mine environment. The field-tested drill bit isolators provided a noise reduction of 3-5 dB(A). Of nine devices tested for durability, five exceeded 610 m (2,000 ft) drilled and two exceeded 762 m (2,500 ft) drilled before failure. Durability issues found in the field tests led to final production optimizations that have resulted in a commercially available product for drilling with 35-mm- (1.3-in.-) diameter roof bits and hexagonal drill steels.
{"title":"Evaluations of a noise control for roof bolting machines.","authors":"A S Azman, D S Yantek, L A Alcorn","doi":"","DOIUrl":"","url":null,"abstract":"<p><p>In collaboration with Kennametal Inc. and Corry Rubber Corporation, the U.S. National Institute for Occupational Safety and Health (NIOSH) developed a drill bit isolator to address noise overexposures associated with roof bolting machines in underground coal mines. NIOSH laboratory studies confirmed that the drill bit isolator reduces noise during drilling. Field studies were needed to confirm that a noise reduction could be obtained under working conditions and that the device was sufficiently durable. This paper reports results of field tests of the device conducted at five underground coal mines. Noise reduction was assessed by comparing the operator's noise exposure during drilling with and without the drill bit isolator. Durability was assessed by recording the number of holes and total feet drilled with each bit isolator until either the test period ended or the device failed. The results from these tests showed that the device is an effective noise control in a mine environment. The field-tested drill bit isolators provided a noise reduction of 3-5 dB(A). Of nine devices tested for durability, five exceeded 610 m (2,000 ft) drilled and two exceeded 762 m (2,500 ft) drilled before failure. Durability issues found in the field tests led to final production optimizations that have resulted in a commercially available product for drilling with 35-mm- (1.3-in.-) diameter roof bits and hexagonal drill steels.</p>","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"64 12","pages":"64-70"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4524800/pdf/nihms706161.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"33970355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In collaboration with Kennametal Inc. and Corry Rubber Corporation, the U.S. National Institute for Occupational Safety and Health (NIOSH) developed a drill bit isolator to address noise overexposures associated with roof bolting machines in underground coal mines. NIOSH laboratory studies confirmed that the drill bit isolator reduces noise during drilling. Field studies were needed to confirm that a noise reduction could be obtained under working conditions and that the device was sufficiently durable. This paper reports results of field tests of the device conducted at five underground coal mines. Noise reduction was assessed by comparing the operator's noise exposure during drilling with and without the drill bit isolator. Durability was assessed by recording the number of holes and total feet drilled with each bit isolator until either the test period ended or the device failed. The results from these tests showed that the device is an effective noise control in a mine environment. The field-tested drill bit isolators provided a noise reduction of 3-5 dB(A). Of nine devices tested for durability, five exceeded 610 m (2,000 ft) drilled and two exceeded 762 m (2,500 ft) drilled before failure. Durability issues found in the field tests led to final production optimizations that have resulted in a commercially available product for drilling with 35-mm- (1.3-in.-) diameter roof bits and hexagonal drill steels.
{"title":"Evaluations of a noise control for roof bolting machines.","authors":"A. Azman, D. Yantek, L. Alcorn","doi":"10.1121/1.4920642","DOIUrl":"https://doi.org/10.1121/1.4920642","url":null,"abstract":"In collaboration with Kennametal Inc. and Corry Rubber Corporation, the U.S. National Institute for Occupational Safety and Health (NIOSH) developed a drill bit isolator to address noise overexposures associated with roof bolting machines in underground coal mines. NIOSH laboratory studies confirmed that the drill bit isolator reduces noise during drilling. Field studies were needed to confirm that a noise reduction could be obtained under working conditions and that the device was sufficiently durable. This paper reports results of field tests of the device conducted at five underground coal mines. Noise reduction was assessed by comparing the operator's noise exposure during drilling with and without the drill bit isolator. Durability was assessed by recording the number of holes and total feet drilled with each bit isolator until either the test period ended or the device failed. The results from these tests showed that the device is an effective noise control in a mine environment. The field-tested drill bit isolators provided a noise reduction of 3-5 dB(A). Of nine devices tested for durability, five exceeded 610 m (2,000 ft) drilled and two exceeded 762 m (2,500 ft) drilled before failure. Durability issues found in the field tests led to final production optimizations that have resulted in a commercially available product for drilling with 35-mm- (1.3-in.-) diameter roof bits and hexagonal drill steels.","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"176 1","pages":"64-70"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"64421850","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Neural networks were used to calibrate an online ash analyzer at the Usibelli Coal Mine, Healy, Alaska, by relating the Americium and Cesium counts to the ash content. A total of 104 samples were collected from the mine, with 47 being from screened coal, and the rest being from unscreened coal. Each sample corresponded to 20 seconds of coal on the running conveyor belt. Neural network modeling used the quick stop training procedure. Therefore, the samples were split into training, calibration and prediction subsets. Special techniques, using genetic algorithms, were developed to representatively split the sample into the three subsets. Two separate approaches were tried. In one approach, the screened and unscreened coal was modeled separately. In another, a single model was developed for the entire dataset. No advantage was seen from modeling the two subsets separately. The neural network method performed very well on average but not individually, i.e. though each prediction was unreliable, the average of a few predictions was close to the true average. Thus, the method demonstrated that the analyzers were accurate at 2-3 minutes intervals (average of 6-9 samples), but not at 20 seconds (each prediction).
{"title":"CALIBRATION OF ONLINE ANALYZERS USING NEURAL NETWORKS","authors":"R. Ganguli, D. Walsh, Shaohai Yu","doi":"10.2172/823299","DOIUrl":"https://doi.org/10.2172/823299","url":null,"abstract":"Neural networks were used to calibrate an online ash analyzer at the Usibelli Coal Mine, Healy, Alaska, by relating the Americium and Cesium counts to the ash content. A total of 104 samples were collected from the mine, with 47 being from screened coal, and the rest being from unscreened coal. Each sample corresponded to 20 seconds of coal on the running conveyor belt. Neural network modeling used the quick stop training procedure. Therefore, the samples were split into training, calibration and prediction subsets. Special techniques, using genetic algorithms, were developed to representatively split the sample into the three subsets. Two separate approaches were tried. In one approach, the screened and unscreened coal was modeled separately. In another, a single model was developed for the entire dataset. No advantage was seen from modeling the two subsets separately. The neural network method performed very well on average but not individually, i.e. though each prediction was unreliable, the average of a few predictions was close to the true average. Thus, the method demonstrated that the analyzers were accurate at 2-3 minutes intervals (average of 6-9 samples), but not at 20 seconds (each prediction).","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"56 1","pages":"99-99"},"PeriodicalIF":0.0,"publicationDate":"2003-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68238096","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Management of mineral resources","authors":"J. Camus","doi":"10.18356/12ba2e67-en","DOIUrl":"https://doi.org/10.18356/12ba2e67-en","url":null,"abstract":"","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"54 1","pages":"17-25"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"67675185","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2002-01-01DOI: 10.1016/s0140-6701(03)90607-2
J. J. Graham
{"title":"Nuclear energy industry: Past, present and future","authors":"J. J. Graham","doi":"10.1016/s0140-6701(03)90607-2","DOIUrl":"https://doi.org/10.1016/s0140-6701(03)90607-2","url":null,"abstract":"","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"54 1","pages":"25-30"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/s0140-6701(03)90607-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"55842137","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"United States, 2001:","authors":"R. F. Balazik, L. Mccartan, D. Morse, S. Sibley","doi":"10.2307/j.ctv125jvcb.13","DOIUrl":"https://doi.org/10.2307/j.ctv125jvcb.13","url":null,"abstract":"","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"102 1","pages":"17-26"},"PeriodicalIF":0.0,"publicationDate":"2002-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68773171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2001-03-01DOI: 10.5791/0882-2875-20.1.18
G. Davis
Traditional finance theory recommends discounted cash flow analysis as the tool to value mineral properties, yet the calculated values are usually lower than the market value. Finance theory also advises us to develop an undeveloped project immediately if its net present value is positive. Most projects are, however, only developed when the economics are highly favorable. This paper uses insights from option pricing theory to explain these divergences between market behavior and finance theory, and presents simple modifications to discounted cash flow analyses that will lead them to produce correct valuation and development timing advice.
{"title":"ONE PROJECT, TWO DISCOUNT RATES","authors":"G. Davis","doi":"10.5791/0882-2875-20.1.18","DOIUrl":"https://doi.org/10.5791/0882-2875-20.1.18","url":null,"abstract":"Traditional finance theory recommends discounted cash flow analysis as the tool to value mineral properties, yet the calculated values are usually lower than the market value. Finance theory also advises us to develop an undeveloped project immediately if its net present value is positive. Most projects are, however, only developed when the economics are highly favorable. This paper uses insights from option pricing theory to explain these divergences between market behavior and finance theory, and presents simple modifications to discounted cash flow analyses that will lead them to produce correct valuation and development timing advice.","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"50 1","pages":"70-74"},"PeriodicalIF":0.0,"publicationDate":"2001-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71042930","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Dense sludge is an innovative and improved method for treating acidic metal bearing streams in a manner which minimizes volumetric generation of sludge for disposal. In the Dense Sludge process, the alkali source is combined with recycled sludge before being introduced into raw water influent, thus forming metal particles with a low affinity for water. The sludge density of clarifier underflow has in some cases increased from the usual 1--2% to nearly 35% solids. This paper will describe installation and operating data from a 9,000 gpm Dense Sludge AMD Treatment Facility at a coal mine in Northern West Virginia.
{"title":"DENSE-SLUDGE PROCESS FOR REDUCED AMD SLUDGE DISPOSAL","authors":"R. Zick, M. H. Leon, D. Finn","doi":"10.21000/JASMR98010257","DOIUrl":"https://doi.org/10.21000/JASMR98010257","url":null,"abstract":"Dense sludge is an innovative and improved method for treating acidic metal bearing streams in a manner which minimizes volumetric generation of sludge for disposal. In the Dense Sludge process, the alkali source is combined with recycled sludge before being introduced into raw water influent, thus forming metal particles with a low affinity for water. The sludge density of clarifier underflow has in some cases increased from the usual 1--2% to nearly 35% solids. This paper will describe installation and operating data from a 9,000 gpm Dense Sludge AMD Treatment Facility at a coal mine in Northern West Virginia.","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"51 1","pages":"26-30"},"PeriodicalIF":0.0,"publicationDate":"1999-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68226179","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
W. Daniels, P. Schroeder, S. Nagle, L. Zelazny, M. Alley
Significant deposits of mineral sands were discovered in Virginia's Upper Coastal Plain in 1989. The Old Hickory deposit is the largest ore body in the state (>2,000 ha) and supports a productive rowcrop agriculture on prime farmlands. field experiments were installed on pilot-scale (25 m x 60 m) mining pits in the late summer of 1995 and replicated on an adjacent undisturbed area. Half of each mining pit was topsoiled (25 cm) while the remaining half was left as either (1) mixed tails/slimes or (2) re-graded subsoil over tails/slimes to simulate various pit closure scenarios. Both non-topsoiled areas received 112 Mg/ha of yard waste compost as a soil building amendment. The entire area was ripped/disked to ameliorate compaction and incorporate lime and fertilizer additions. The experiment was cropped through a wheat/soybeans/corn/cotton rotation over the 1995 to 1998 growing seasons. Taken as a whole, these combined results clearly indicate that mining and reclamation of these prime farmlands will lead to a substantial decrease in rowcrop productivity, at least over the initial years following pit closure and reclamation. For the rotation studied, post-mining productivity was estimated by this experiment to be reduced by 23%, 3%, 27%, and 20% for each crop (wheat/soybeans/corn/cotton)more » in sequence. For a given crop in a given year, response to topsoiling versus compost addition to the surface varied, and neither treatment appeared superior. Corn and cotton yields on the mined land treatments were reduced despite the application of irrigation. Cotton quality was also adversely affected by the mining reclamation treatments. Results of these controlled experiments are somewhat encouraging. However, the implementation of protocols will be complicated in practice if tailings and slimes cannot be re-blended to generate a reasonably uniform final reclaimed surface.« less
{"title":"Reclamation of prime farmland following mineral sands mining in Virginia","authors":"W. Daniels, P. Schroeder, S. Nagle, L. Zelazny, M. Alley","doi":"10.21000/JASMR99010146","DOIUrl":"https://doi.org/10.21000/JASMR99010146","url":null,"abstract":"Significant deposits of mineral sands were discovered in Virginia's Upper Coastal Plain in 1989. The Old Hickory deposit is the largest ore body in the state (>2,000 ha) and supports a productive rowcrop agriculture on prime farmlands. field experiments were installed on pilot-scale (25 m x 60 m) mining pits in the late summer of 1995 and replicated on an adjacent undisturbed area. Half of each mining pit was topsoiled (25 cm) while the remaining half was left as either (1) mixed tails/slimes or (2) re-graded subsoil over tails/slimes to simulate various pit closure scenarios. Both non-topsoiled areas received 112 Mg/ha of yard waste compost as a soil building amendment. The entire area was ripped/disked to ameliorate compaction and incorporate lime and fertilizer additions. The experiment was cropped through a wheat/soybeans/corn/cotton rotation over the 1995 to 1998 growing seasons. Taken as a whole, these combined results clearly indicate that mining and reclamation of these prime farmlands will lead to a substantial decrease in rowcrop productivity, at least over the initial years following pit closure and reclamation. For the rotation studied, post-mining productivity was estimated by this experiment to be reduced by 23%, 3%, 27%, and 20% for each crop (wheat/soybeans/corn/cotton)more » in sequence. For a given crop in a given year, response to topsoiling versus compost addition to the surface varied, and neither treatment appeared superior. Corn and cotton yields on the mined land treatments were reduced despite the application of irrigation. Cotton quality was also adversely affected by the mining reclamation treatments. Results of these controlled experiments are somewhat encouraging. However, the implementation of protocols will be complicated in practice if tailings and slimes cannot be re-blended to generate a reasonably uniform final reclaimed surface.« less","PeriodicalId":91142,"journal":{"name":"Mining engineering","volume":"55 1","pages":"27-33"},"PeriodicalIF":0.0,"publicationDate":"1999-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"68225726","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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