Assessing the effect of mine subsidence on dwarf shrub ericoid heath communities within a site of national importance

DOE Office of Scientific and Technical Information (OSTI.GOV)

Humphries, R.N.; Wessemann, H.; Benyon, P.R.

1998-12-31

Planning consent was applied for in 1997 to extract coal from the Stanley Main seam beneath Skipwith Common, North Yorkshire in the United Kingdom. The 293ha Common is of national importance for its dwarf shrub ericoid heath communities, and has statutory protection under UK law as a Site of Special Scientific Interest (SSSI). Current planning guidance requires the effects of the mining proposals to be rigorously examined. The distribution of the heath vegetation is largely determined by the surface topography and sub-surface clay features, these determine relative site subsidence on drainage, and hence soil wetness and heath vegetation. Up tomore » date topographical, soil and vegetation surveys were undertaken. This data was used in conjunction with the mining company`s subsidence predictions to model the effects of the mining of the previous and deeper Barnsley seam, as well as the proposed extraction of the Stanley Main seam. Overall, the model predicted there would be no adverse effect of subsidence from the mining of the Barnsley seam or cumulative effects following the extraction of the Stanley Main seam on the site features which determine relative wetness and heath distribution. The prediction for the Barnsley seam was tested using past and current vegetation and soil wetness records. On a broad scale, there was no field evidence that the previous mining has resulted in a reduction in the extent of ericiod heath communities within the SSSI. On a local scale, there was some evidence for a very small effect at the one location where a potential effect was predicted. As the principal physical changes to the SSSI are induced by the previous mining of the Barnsley seam, no further effects were predicted for extracting the Stanley Main seam. The modelling approach has proved to be valuable, both technically and as a means of explaining the potential effects of mining on a nationally important nature conservation site to various interested parties, including the regulatory bodies.« less

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

NASA Astrophysics Data System (ADS)

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.

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

PubMed Central

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

Ground penetrating radar coal measurements demonstration at the U.S. Bureau of Mines Research Center, Pittsburgh, Pennsylvania. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gardner, D.; Guerrier, J.; Martinez, M.

1994-01-04

In situ and near real-time measurements of coal seam thickness have been identified by industry as a highly desirable component of robotic mining systems. With it, a continuous mining machine can be guided close to the varying boundary of the seam while the cutting operation is underway. This provides the mining operation the ability to leave behind the high-sulfur, high-particulate coal which is concentrated near the seam boundary. The result is near total recovery of high quality coal resources, an increase in mining efficiency, and opportunities for improved safety through reduction in personnel in the most hazardous coal cutting areas.more » In situ, real-time coal seam measurements using the Special Technologies Laboratory (STL) ground penetrating radar (GPR) technology were shown feasible by a demonstration in a Utah coal mine on April 21, 1994. This report describes the October 18, 1994 in situ GPR measurements of coal seam thickness at the US Bureau of Mines (USBM) robotic mining testing laboratory. In this report, an overview of the measurements at the USBM Laboratory is given. It is followed by a description of the technical aspects of the STL frequency modulated-continuous wave (FM-CW) GPR system. Section 4 provides a detailed description of the USBM Laboratory measurements and the conditions under which they were taken. Section 5 offers conclusions and possibilities for future communications.« less

Corner-cutting mining assembly

DOEpatents

Bradley, J.A.

1981-07-01

This invention resulted from a contract with the United States Department of Energy and relates to a mining tool. More particularly, the invention relates to an assembly capable of drilling a hole having a square cross-sectional shape with radiused corners. In mining operations in which conventional auger-type drills are used to form a series of parallel, cylindrical holes in a coal seam, a large amount of coal remains in place in the seam because the shape of the holes leaves thick webs between the holes. A higher percentage of coal can be mined from a seam by a means capable of drilling holes having a substantially square cross section. It is an object of this invention to provide an improved mining apparatus by means of which the amount of coal recovered from a seam deposit can be increased. Another object of the invention is to provide a drilling assembly which cuts corners in a hole having a circular cross section. These objects and other advantages are attained by a preferred embodiment of the invention.

30 CFR 75.501-1 - Coal seams above the water table.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Coal seams above the water table. 75.501-1 Section 75.501-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.501...

30 CFR 75.501-1 - Coal seams above the water table.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Coal seams above the water table. 75.501-1 Section 75.501-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.501...

30 CFR 75.501-1 - Coal seams above the water table.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Coal seams above the water table. 75.501-1 Section 75.501-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.501...

30 CFR 75.501-1 - Coal seams above the water table.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Coal seams above the water table. 75.501-1 Section 75.501-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.501...

30 CFR 75.501-1 - Coal seams above the water table.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Coal seams above the water table. 75.501-1 Section 75.501-1 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Electrical Equipment-General § 75.501...

Methane Content Estimation in DuongHuy Coal Mine

NASA Astrophysics Data System (ADS)

Nguyen, Van Thinh; Mijał, Waldemar; Dang, Vu Chi; Nguyen, Thi Tuyet Mai

2018-03-01

Methane hazard has always been considered for underground coal mining as it can lead to methane explosion. In Quang Ninh province, several coal mines such as Mạo Khe coal mine, Khe Cham coal mine, especially Duong Huy mine that have high methane content. Experimental data to examine contents of methane bearing coal seams at different depths are not similar in Duong coal mine. In order to ensure safety, this report has been undertaken to determine a pattern of changing methane contents of coal seams at different exploitation depths in Duong Huy underground coal mine.

The migration law of overlay rock and coal in deeply inclined coal seam with fully mechanized top coal caving.

PubMed

Liu, Jian; Chen, Shan-Le; Wang, Hua-Jun; Li, Yu-Cheng; Geng, Xiaowei

2015-07-01

In a mine area, some environment geotechnics problems always occure, induced by mined-out region such as the subsidence and cracks at ground level, deformation and destruction of buildings, landslides destruction of water resources and the ecological environment. In order to research the migration of surrounding rock and coal in steeply inclined super high seams which used fully mechanized top coal caving, a working face of a certain mine was made as an example, analyzed the migration law of the overlay rock and coal under different caving ratio of fully mechanized top coal caving with numerical simulation analysis. The results suggest that the laws of overlay rock deformation caused by deeply inclined coal seam were different from horizontal coal seam. On the inclined direction, with an increase of dip angle and caving ratio, the vertical displacement of overlay rock and coal became greater, the asymmetric phenomenon of vertical displacement became obvious. On the trend direction, active region and transition region in goaf became smaller along with the increase of mining and caving ratio. On the contrary, the stable region area became greater. Therefore, there was an essential difference between the mechanism of surface movement deformation with deeply inclined coal seam and that with horizontal coal seam.

Assessment of practicality of remote sensing techniques for a study of the effects of strip mining in Alabama

NASA Technical Reports Server (NTRS)

Hughes, T. H.; Dillion, A. C., III; White, J. R., Jr.; Drummond, S. E., Jr.; Hooks, W. G.

1975-01-01

Because of the volume of coal produced by strip mining, the proximity of mining operations, and the diversity of mining methods (e.g. contour stripping, area stripping, multiple seam stripping, and augering, as well as underground mining), the Warrior Coal Basin seemed best suited for initial studies on the physical impact of strip mining in Alabama. Two test sites, (Cordova and Searles) representative of the various strip mining techniques and environmental problems, were chosen for intensive studies of the correlation between remote sensing and ground truth data. Efforts were eventually concentrated in the Searles Area, since it is more accessible and offers a better opportunity for study of erosional and depositional processes than the Cordova Area.

Influence of Geological Structure on Coal and Gas Outburst Occurrences in Turkish Underground Coal Mines

NASA Astrophysics Data System (ADS)

Esen, Olgun; Özer, Samet Can; Fişne, Abdullah

2015-04-01

Coal and gas outbursts are sudden and violent releases of gas and in company with coal that result from a complex function of geology, stress regime with gas pressure and gas content of the coal seam. The phenomena is referred to as instantaneous outbursts and have occurred in virtually all the major coal producing countries and have been the cause of major disasters in the world mining industry. All structures from faults to joints and cleats may supply gas or lead to it draining away. Most geological structures influence the way in which gas can drain within coal seams. From among all the geological factors two groups can be distinguished: parameters characterising directly the occurrence and geometry of the coal seams; parameters characterising the tectonic disturbances of the coal seams and neighbouring rocks. Also dykes may act as gas barriers. When the production of the coal seam is advanced in mine working areas, these barriers are failed mostly in the weak and mylonitized zones. Geology also plays a very important role in the outburst process. Coal seams of complex geological structure including faults, folds, and fractured rocks are liable to outbursts if coal seams and neighbouring rocks have high gas content level. The purpose of the study is to enlighten the coal industry in Turkey to improving mine safety in underground coal production and decrease of coal and gas outburst events due to increasing depth of mining process. In Turkey; the years between 1969 and 2013, the number of 90 coal and gas outbursts took place in Zonguldak Hard Coal Basin in both Kozlu and Karadon Collieries. In this study the liability to coal and gas outburst of the coal seams are investigated by measuring the strength of coal and the rock pressure. The correlation between these measurements and the event locations shows that the geological structures resulted in 52 events out of 90 events; 19 events close to the fault zones, 25 events thorough the fault zones and 8 events in the zones where sudden changes of inclination and/or thickness of the coal seam.

Mechanism of Rock Burst Occurrence in Specially Thick Coal Seam with Rock Parting

NASA Astrophysics Data System (ADS)

Wang, Jian-chao; Jiang, Fu-xing; Meng, Xiang-jun; Wang, Xu-you; Zhu, Si-tao; Feng, Yu

2016-05-01

Specially thick coal seam with complex construction, such as rock parting and alternative soft and hard coal, is called specially thick coal seam with rock parting (STCSRP), which easily leads to rock burst during mining. Based on the stress distribution of rock parting zone, this study investigated the mechanism, engineering discriminant conditions, prevention methods, and risk evaluation method of rock burst occurrence in STCSRP through setting up a mechanical model. The main conclusions of this study are as follows. (1) When the mining face moves closer to the rock parting zone, the original non-uniform stress of the rock parting zone and the advancing stress of the mining face are combined to intensify gradually the shearing action of coal near the mining face. When the shearing action reaches a certain degree, rock burst easily occurs near the mining face. (2) Rock burst occurrence in STCSRP is positively associated with mining depth, advancing stress concentration factor of the mining face, thickness of rock parting, bursting liability of coal, thickness ratio of rock parting to coal seam, and difference of elastic modulus between rock parting and coal, whereas negatively associated with shear strength. (3) Technologies of large-diameter drilling, coal seam water injection, and deep hole blasting can reduce advancing stress concentration factor, thickness of rock parting, and difference of elastic modulus between rock parting and coal to lower the risk of rock burst in STCSRP. (4) The research result was applied to evaluate and control the risk of rock burst occurrence in STCSRP.

Determination of Destress Blasting Effectiveness Using Seismic Source Parameters

NASA Astrophysics Data System (ADS)

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.

Time-lapse analysis of methane quantity in Mary Lee group of coal seams using filter-based multiple-point geostatistical simulation

USGS Publications Warehouse

Karacan, C. Özgen; Olea, Ricardo A.

2013-01-01

The systematic approach presented in this paper is the first time in literature that history matching, TIs of GIPs and filter simulations are used for degasification performance evaluation and for assessing GIP for mining safety. Results from this study showed that using production history matching of coalbed methane wells to determine time-lapsed reservoir data could be used to compute spatial GIP and representative GIP TIs generated through Voronoi decomposition. Furthermore, performing filter simulations using point-wise data and TIs could be used to predict methane quantity in coal seams subjected to degasification. During the course of the study, it was shown that the material balance of gas produced by wellbores and the GIP reductions in coal seams predicted using filter simulations compared very well, showing the success of filter simulations for continuous variables in this case study. Quantitative results from filter simulations of GIP within the studied area briefly showed that GIP was reduced from an initial ∼73 Bcf (median) to ∼46 Bcf (2011), representing a 37 % decrease and varying spatially through degasification. It is forecasted that there will be an additional ∼2 Bcf reduction in methane quantity between 2011 and 2015. This study and presented results showed that the applied methodology and utilized techniques can be used to map GIP and its change within coal seams after degasification, which can further be used for ventilation design for methane control in coal mines.

An analysis of injury claims from low-seam coal mines

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gallagher, S.; Moore, S.; Dempsey, P.G.

2009-07-01

The restricted workspace present in low-seam coal mines forces workers to adopt awkward working postures (kneeling and stooping), which place high physical demands on the knee and lower back. This article provides an analysis of injury claims for eight mining companies operating low-seam coal mines during calendar years 1996-2008. All cost data were normalized using data on the cost of medical care (MPI) as provided by the U.S. Bureau of Labor Statistics. Results of the analysis indicate that the knee was the body part that led in terms of claim cost ($4.2 million), followed by injuries to the lower backmore » ($2.7 million). While the average cost per injury for these body parts was $13,100 and $14,400, respectively (close to the average cost of an injury overall), the high frequency of these injuries resulted in their pre-eminence in terms of cost. Analysis of data from individual mining companies suggest that knee and lower back injuries were a consistent problem across companies, as these injuries were each among the top five most costly part of body for seven out of eight companies studied. Results of this investigation suggest that efforts to reduce the frequency of knee and low back injuries in low-seam mines have the potential to create substantial cost savings.« less

Petrographic and geochemical contrasts and environmentally significant trace elements in marine-influenced coal seams, Yanzhou mining area, China

USGS Publications Warehouse

Liu, Gaisheng; Yang, P.; Peng, Z.; Chou, C.-L.

2004-01-01

The Yanzhou mining area in west Shandong Province, China contains coals of Permian and Carboniferous age. The 31 and 32 seams of the Permian Shanxi Formation and seams 6, 15-17 of the Carboniferous Taiyuan Formation were analyzed for coal petrology, mineralogy and geochemical parameters. The parameters indicate that the coal is high volatile bituminous in rank. The coal is characterized by high vitrinite and low to medium inertinite and liptinite contents. These properties may be related to evolution of the coal forming environment from more reducing conditions in a marine influenced lower delta plain environment for the early Taiyuan coals to more oxidizing paleoenvironments in an upper delta plain for the upper Shanxi coal seams. The major mineral phases present in the coal are quartz, kaolinite, pyrite and calcite. Sulfur is one of the hazardous elements in coal. The major forms of sulfur in coal are pyritic, organic and sulfate sulfur. Pyritic and organic sulfur generally account for the bulk of the sulfur in coal. Elemental sulfur also occurs in coal, but only in trace to minor amounts. In this paper, the distribution and concentration of sulfur in the Yanzhou mining district are analyzed, and the forms of sulfur are studied. The sulfur content of the Taiyuan coal seams is considerably higher than that of the Shanxi coals. Organic sulfur content is positively correlated to total and pyritic sulfur. The vertical variation of Cu, Zn, Pb, As, Th, U and sulfur contents in coal seam 3 of the Shanxi Formation in the Xinglongzhuang mine show that all these trace elements, with the exception of Th, are enriched in the top and bottom plies of the seam, and that their concentrations are also relatively high in the dirt bands within the seam. The pyritic sulfur is positively correlated with total sulfur, and both are enriched in the top, bottom and parting plies of the seam. The concentrations of the trace elements are closely related to sulfur and ash contents. Most of the trace elements are correlated with the ash content, and may be associated with the mineral matter in the coal. ?? 2004 Elsevier Ltd. All rights reserved.

Characteristics of the Roof Behaviors and Mine Pressure Manifestations During the Mining of Steep Coal Seam

NASA Astrophysics Data System (ADS)

Hong-Sheng, Tu; Shi-Hao, Tu; Cun, Zhang; Lei, Zhang; Xiao-Gang, Zhang

2017-12-01

A steep seam similar simulation system was developed based on the geological conditions of a steep coal seam in the Xintie Coal Mine. Basing on similar simulation, together with theoretical analysis and field measurement, an in-depth study was conducted to characterize the fracture and stability of the roof of steep working face and calculate the width of the region backfilled with gangue in the goaf. The results showed that, as mining progressed, the immediate roof of the steep face fell upon the goaf and backfilled its lower part due to gravity. As a result, the roof in the lower part had higher stability than the roof in the upper part of the working face. The deformation and fracture of main roof mainly occurred in the upper part of the working face; the fractured main roof then formed a "voussoir beam" structure in the strata's dip direction, which was subjected to the slip- and deformation-induced instability. The stability analysis indicated that, when the dip angle increased, the rock masses had greater capacity to withstand slip-induced instability but smaller capacity to withstand deformation-induced instability. Finally, the field measurement of the forces exerted on the hydraulic supports proved the characteristics of the roof's behaviors during the mining of a steep seam.

Study on Resources Assessment of Coal Seams covered by Long-Distance Oil & Gas Pipelines

NASA Astrophysics Data System (ADS)

Han, Bing; Fu, Qiang; Pan, Wei; Hou, Hanfang

2018-01-01

The assessment of mineral resources covered by construction projects plays an important role in reducing the overlaying of important mineral resources and ensuring the smooth implementation of construction projects. To take a planned long-distance gas pipeline as an example, the assessment method and principles for coal resources covered by linear projects are introduced. The areas covered by multiple coal seams are determined according to the linear projection method, and the resources covered by pipelines directly and indirectly are estimated by using area segmentation method on the basis of original blocks. The research results can provide references for route optimization of projects and compensation for mining right..

Underground gas storage in the Leyden lignite mine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Meddles, R.M.

1978-01-01

Underground gas storage in the Leyden lignite mine by Public Service Co. of Colorado was preceded by careful studies of mine records with respect to geologic conditions and investigation of the gas-sealing potential of the rocks surrounding the cavern. The water level in shaft No. 3 in Sept. 1958 was about 100 ft above the coal seam at that point. Wells were drilled into the mine up-dip (east) of the structurally highest point that a mine shaft intersected the coal seams, and gas was injected into the mine, using the mine water as a seal. At least the up-dip partmore » of the mine was gas-tight, and tests were expanded to the rest of the mine, which also proved to be gas-tight. All that remained to complete the preparation of the mine for permanent gas storage was sealing of the old mine shafts.« less

Spatial Variation of Selenium in Appalachian Coal Seams

NASA Astrophysics Data System (ADS)

Le, L.; Tyner, J. S.; Perfect, E.; Yoder, D. C.

2013-12-01

The potential environmental impacts from coal extraction have led to many investigations of the geochemistry of coal. Previous studies have shown that selenium (Se) is an environmental contaminant due to its mutagenic effects on sensitive macro-organisms as a result of bioaccumulation in affected waters. Some regulatory authorities have responded by requiring the sampling of coal seams and adjacent rock for Se prior to authorizing a given coal mining permit. In at least one case, a single continuous rock core was sampled for Se to determine the threshold of Se across a 2.2 square kilometer proposed surface coal mine. To examine the adequacy of such an approach, we investigated the spatial variability and correlation of a West Virginia Geological and Economic Survey (WVGES) dataset of Se concentrations from coal seams collected within Appalachia (1088 samples). We conducted semi-variogram and Kriging cross-validation analyses on six coal seams from the dataset. Our findings suggest no significant spatial correlation of Se within a given coal seam.

Microcomputer keeps watch at Emerald Mine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1987-04-01

Where there's smoke, there's fire. Take the old adage a step further: ''Where there's carbon monoxide, there's likely to be a fire.'' That's the principle behind the mine monitoring system being used at the Emerald Mine operated by Emway Resources. Instead of watching for smoke or temperature rises, the system uses carbon monoxide (CO) sensors to detect fires - before they break out. CO, a gaseous product of incomplete combustion, is present in the early stages of a fire. Carried by the mine ventilation air, CO can be quickly traced by electrochemical gas sensors that are wired to a centralmore » computer. When preset levels are reached, alarms can alert mine personnel of the trouble. The Emerald Mine is located in southwestern Pennsylvania, near Waynesburg, and mines the Pittsburgh Seam, the nation's most heavily mined seam. Emerald is one of a number of progressive mines that are turning to computers to improve safety and productivity.« less

Rational Use of Land Resource During the Implementation of Transportless System of Coal Strata Surface Mining

NASA Astrophysics Data System (ADS)

Gvozdkova, T.; Tyulenev, M.; Zhironkin, S.; Trifonov, V. A.; Osipov, Yu M.

2017-01-01

Surface mining and open pits engineering affect the environment in a very negative way. Among other pollutions that open pits make during mineral deposits exploiting, particular problem is the landscape changing. Along with converting the land into pits, surface mining is connected with pilling dumps that occupy large ground. The article describes an analysis of transportless methods of several coal seams strata surface mining, applied for open pits of South Kuzbass coal enterprises (Western Siberia, Russia). To improve land-use management of open pit mining enterprises, the characteristics of transportless technological schemes for several coal seams strata surface mining are highlighted and observed. These characteristics help to systematize transportless open mining technologies using common criteria that characterize structure of the bottom part of a strata and internal dumping schemes. The schemes of transportless systems of coal strata surface mining implemented in South Kuzbass are given.

Adult Education and Radical Habitus in an Environmental Campaign: Learning in the Coal Seam Gas Protests in Australia

ERIC Educational Resources Information Center

Ollis, Tracey; Hamel-Green, Michael

2015-01-01

This paper examines the adult learning dimensions of protestors as they participate in a campaign to stop coal seam gas exploration in Gippsland in Central Victoria, Australia. On a global level, the imposition of coal seam gas exploration by governments and mining companies has been the trigger for movements of resistance from environmental…

Methane drainage at the Minerales Monclova mines in the Sabinas coal basin, Coahuila, Mexico

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brunner, D.J.; Ponce, J.R.

Minerales Monclova S.A. De C.V. (MIMOSA) operates five underground longwall mines in the Gassy Los Olmos Coals of the Sabinas Basin in the state of Coahuila in Northern Mexico. Because of high in-situ gas contents and high cleat and natural fracture permeability, MIMOSA has had to incorporate a system of methane drainage in advance of mining in order to safely and cost effectively exploit their reserves. In the early 1990s Resource Enterprises (REI) conducted reservoir characterization tests, numerical simulations, and Coal Mine Methane (CMM) production tests at a nearby mine property in the same basin. Using this information REI approachedmore » MIMOSA and recommended the mine-wide implementation of a degasification system that involves long in-seam directionally drilled boreholes. REI was contracted to conduct the drilling, and to date has drilled over 26,000 m (85,000 ft) of in-seam borehole in advance of mining developments, reducing gas contents significantly below in-situ values. This paper discusses the basis for the degasification program recommended at the MIMOSA mines, and presents the impact of its mine-wide application on MIMOSA's mining operations over the last six years. The paper focuses on the degasification system's impacts on methane emissions into mine workings, coal production, and ventilation demands. It also presents lessons learned by the degasification planners in implementing in-seam methane drainage. The paper presents actual CMM production data, measurements of methane emissions and advance rates at development sections, and mine methane liberations.« less

Analysis of alternatives for using cable bolts as primary support at two low-seam coal mines

PubMed Central

Esterhuizen, Gabriel S.; Tulu, Ihsan B.

2016-01-01

Cable bolts are sometimes used in low-seam coal mines to provide support in difficult ground conditions. This paper describes cable bolting solutions at two low-seam coal mines in similar ground conditions. Both mines used support systems incorporating cable bolts as part of the primary support system. Two original cable bolt based support systems as well as two modified systems are evaluated to estimate their ability to prevent large roof falls. One of the support systems incorporated passive cable bolts, while the other used pre-tensioned cable bolts. The results and experience at the mines showed that the modified systems provided improved stability over the original support systems. The presence of the cable bolts is the most important contribution to stability against large roof falls, rather than the details of the support pattern. It was also found that a heavy steel channel can improve the safety of the system because of the ‘sling’ action it provides. Additionally, the analysis showed that fully-grouted rebar bolts load much earlier than the cable bolts, and pre-tensioning of the cable bolts can result in a more uniform distribution of loading in the roof. PMID:27722019

Variability of Mercury Content in Coal Matter From Coal Seams of The Upper Silesia Coal Basin

NASA Astrophysics Data System (ADS)

Wierzchowski, Krzysztof; Chećko, Jarosław; Pyka, Ireneusz

2017-12-01

The process of identifying and documenting the quality parameters of coal, as well as the conditions of coal deposition in the seam, is multi-stage and extremely expensive. The taking and analyzing of seam samples is the method of assessment of the quality and quantity parameters of coals in deep mines. Depending on the method of sampling, it offers quite precise assessment of the quality parameters of potential commercial coals. The main kind of seam samples under consideration are so-called "documentary seam samples", which exclude dirt bands and other seam contaminants. Mercury content in coal matter from the currently accessible and exploited coal seams of the Upper Silesian Coal Basin (USCB) was assessed. It was noted that the mercury content in coal seams decreases with the age of the seam and, to a lesser extent, seam deposition depth. Maps of the variation of mercury content in selected lithostratigraphic units (layers) of the Upper Silesian Coal Basin have been created.

Explosive fluid transmitted shock method for mining deeply buried coal

DOEpatents

Archibald, Paul B.

1976-06-22

A method for recovering coal from deeply buried deposits comprising drilling a hole down into a coal seam, filling the hole with water, and periodically detonating an explosive charge at the bottom of the water-filled hole. The water transmits the explosive shock wave to the face of the coal seam, thereby fracturing and dislodging the coal. The resulting suspension of loose coal in water is then pumped to the surface where the coal is recovered and the water is recycled to the mining operation.

Longevity of acid discharges from underground mines located above the regional water table.

PubMed

Demchak, J; Skousen, J; McDonald, L M

2004-01-01

The duration of acid mine drainage flowing out of underground mines is important in the design of watershed restoration and abandoned mine land reclamation projects. Past studies have reported that acid water flows from underground mines for hundreds of years with little change, while others state that poor drainage quality may last only 20 to 40 years. More than 150 above-drainage (those not flooded after abandonment) underground mine discharges from Pittsburgh and Upper Freeport coal seams were located and sampled during 1968 in northern West Virginia, and we revisited 44 of those sites in 1999-2000 and measured water flow, pH, acidity, Fe, sulfate, and conductivity. We found no significant difference in flows between 1968 and 1999-2000. Therefore, we felt the water quality data could be compared and the data represented real changes in pollutant concentrations. There were significant water quality differences between year and coal seam, but no effect of disturbance. While pH was not significantly improved, average total acidity declined 79% between 1968 and 1999-2000 in Pittsburgh mines (from 66.8 to 14 mmol H+ L(-1)) and 56% in Upper Freeport mines (from 23.8 to 10.4 mmol H+ L(-1)). Iron decreased an average of about 80% across all sites (from an average of 400 to 72 mg L(-1)), while sulfate decreased between 50 and 75%. Pittsburgh seam discharge water was much worse in 1968 than Upper Freeport seam water. Twenty of our 44 sites had water quality information in 1980, which served as a midpoint to assess the slope of the decline in acidity and metal concentrations. Five of 20 sites (25%) showed an apparent exponential rate of decline in acidity and iron, while 10 of 20 sites (50%) showed a more linear decline. Drainage from five Upper Freeport sites increased in acidity and iron. While it is clear that surface mines and below-drainage underground mines improve in discharge quality relatively rapidly (20-40 years), above-drainage underground mines are not as easily predicted. In total, the drainage from 34 out of 44 (77%) above-drainage underground mines showed significant improvement in acidity over time, some exponentially and some linearly. Ten discharges showed no improvement and three of these got much worse.

30 CFR 75.381 - Escapeways; anthracite mines.

Code of Federal Regulations, 2010 CFR

2010-07-01

....381 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND HEALTH MANDATORY SAFETY STANDARDS-UNDERGROUND COAL MINES Ventilation § 75.381 Escapeways; anthracite... by 5 feet high. If the pitch or thickness of the coal seam does not permit these dimensions to be...

Coal deposits of the United States

USGS Publications Warehouse

John, Nelson W.

1987-01-01

The coal fields of the Unites States can be divided into six major provinces. The Appalachian and Interior Provinces contain dominantly bituminous coal in strata of Pennsylvanian age. The coal seams are relatively thin and are mined both by surface and underground methods. Sulfyur content is low to moderate in the Appalachian Province, generally high in the Interior province. The Gulf Coastal Plain Province, in Texas and neighboring states, contains lignite of Eocene age. The seams are 3-25 ft (0.9-7.5 m) thick and are minded in large open pits. The Northern Great Plains Province has lignite and subbituminous coal of Cretaceous, Paleocene and Eocene age. The coal, largely very low in sulfur, occurs in beds up to 100 ft (30 m) thick and is strip-mined. The Rocky Mountain Province contains a great variety of coal deposits in numerous separate intermontane basins. Most of it is low-sulfur subbituminous to bituminous coal iof Creatceous and early Tertiary age. The seams range from a few feet to over 100 ft (30 m) thick. Strip-mining dominates but underground mines are important in Utah and Colorado. The Pacific Coast Province, which includes Alaska, contains enormous cola resources but has seen little mining. The coal is highly diverse in physical character and geologic setting. ?? 1987.

Mining geology of the Pond Creek seam, Pikeville Formation, Middle Pennsylvanian, in part of the Eastern Kentucky Coal Field, USA

USGS Publications Warehouse

Greb, S.F.; Popp, J.T.

1999-01-01

The Pond Creek seam is one of the leading producers of coal in the Eastern Kentucky Coal Field. The geologic factors that affect mining were investigated in several underground mines and categorized in terms of coal thickness, coal quality, and roof control. The limits of mining and thick coal are defined by splitting along the margin of the coal body. Within the coal body, local thickness variation occurs because of (1) leader coal benches filling narrow, elongated depressions, (2) rider coal benches coming near to or merging with the main bench, (3) overthrust coal benches being included along paleochannel margins, (4) cutouts occuring beneath paleochannels, and (5) very hard and unusual rock partings occuring along narrow, elongated trends. In the study area, the coal is mostly mined as a compliance product: sulfur contents are less than 1% and ash yields are less than 10%. Local increases in sulfur occur beneath sandstones, and are inferred to represent post-depositional migration of fluids through porous sands into the coal. Run-of-mine quality is also affected by several mine-roof conditions and trends of densely concentrated rock partings, which lead to increased in- and out-of-seam dilution and overall ash content of the mined coal. Roof control is largely a function of a heterolithic facies mosaic of coastal-estuarine origin, regional fracture trends, and unloading stress related to varying mine depth beneath the surface. Lateral variability of roof facies is the rule in most mines. The largest falls occur beneath modern valleys and parallel fractures, along paleochannel margins, within tidally affected 'stackrock,' and beneath rider coals. Shale spalling, kettlebottoms, and falls within other more isolated facies also occur. Many of the lithofacies, and falls related to bedding weaknesses within or between lithofacies, occur along northeast-southwest trends, which can be projected in advance of mining. Fracture-related falls occur independently of lithofacies trends along northwest-southeast trends, especially beneath modern valleys where overburden thickness decreases sharply. Differentiating roof falls related to these trends can aid in predicting roof quality in advance of mining.The Pond Creek-Lower Elkhorn seam has been an important exploration target because it typically has very low sulfur contents and ash yields. Geologic research in several large Pond Creek mines suggested variability in roof quality and coal thickness. Due to mine access, geologic problems encountered during mining are documented and described.

Spiced-up ANFO mixture leads to super blasts for casting

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chironis, N.P.

1984-05-01

There is one problem common to many coal operators in the mountainous regions of western Pennsylvania. As coal seams nearer the crop lines of their mine sites are removed, the overburden heights and stripping ratios increase to about 20-to-1, the range where coal becomes uneconomical to mine. Faced with this situation, a mine operator usually pursues one of four options: 1. Drive a drift mine, which means switching to underground operations with all the complexity and costs involved; 2. Purchase a larger dragline, which involves huge capital expenditures; 3. Bring in an augering machine to auger the exposed seams, amore » technique effective only for a very limited distance into the highwalls; 4. Discontinue operations, the route most operators take.« less

Phosphorus minerals in tonstein; coal seam 405 at Sośnica-Makoszowy coal mine, Upper Silesia, southern Poland

NASA Astrophysics Data System (ADS)

Kokowska-Pawłowska, Magdalena; Nowak, Jacek

2013-06-01

Kokowska-Pawłowska, M. and Nowak, J. 2013. Phosphorus minerals in tonstein; coal seam 405 at Sośnica- Makoszowy coal mine, Upper Silesia, southern Poland. Acta Geologica Polonica, 63 (2), 271-281. Warszawa. The paper presents results of research on tonstein, which constitutes an interburden in coal seam 405 at the Sośnica- Makoszowy coal mine, Makoszowy field (mining level 600 m), Upper Silesia, southern Poland. The mineral and chemical compositions of the tonstein differ from the typical compositions described earlier for tonsteins from Upper Silesia Coal Basin area. Additionally, minerals present in the tonsteins include kaolinite, quartz, kaolinitised biotite and feldspars. The presence of the phosphatic minerals apatite and goyazite has been recognized. The presence of gorceixite and crandallite is also possible. The contents of CaO (5.66 wt%) and P2O5 (6.2 wt%) are remarkably high. Analysis of selected trace elements demonstrated high contents of Sr (4937 ppm) and Ba (4300 ppm), related to the phosphatic minerals. On the basis of mineral composition the tonstein has been identified as a crystalline tonstein, transitional to a multiplied one.

Subjacent support: A right afforded to surface estates alone?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shuman, R.L.

1995-11-01

The right of subjacent support that is enjoyed by surface estates is also enjoyed by subsurface horizontal estates, unless waived either expressly or by necessary implication. Whether the West Virginia Surface Coal Mining and Reclamation Act protects subsurfaces interests or not, the subjacent support rights of overlying coal seams is determined by the way of the following analysis. First, was the superincumbent coal seam severed first in time? If so, the right of subjacent support is intact and unwaived. Second, if the overlying seam was not severed first in time, did the earlier severance of the underlying seam waive themore » right to subjacent support for all overlying strata. If not, the right to subjacent support is maintained. If so, was the waiver specific and did it encompass matters within the contemplation of the parties at the time of its execution? In addition, can a substantial policy arguement be waged against the waiver? The analysis is one of {open_quotes}first in time.{close_quotes} As the search for new energy sources quickens and technology improves to the point where coal seams that were once uneconomical to mine become recoverable from a cost-benefit approach, the conflicts arising between the owners of overlying and underlying coal seams will become more frequent and more pertinent to the energy requirements of West Virginia and the nation.« less

Responses of Terrestrial Herpetofauna to Persistent, Novel Ecosystems Resulting from Mountaintop Removal Mining

Treesearch

Jennifer M. Williams; Donald J. Brown; Petra B. Wood

2017-01-01

Mountaintop removal mining is a large-scale surface mining technique that removes entire floral and faunal communities, along with soil horizons located above coal seams. In West Virginia, the majority of this mining occurs on forested mountaintops. However, after mining ceases the land is typically reclaimed to grasslands and shrublands, resulting in novel ecosystems...

Method of underground mining by pillar extraction

DOEpatents

Bowen, Ray J.; Bowen, William R.

1980-08-12

A method of sublevel caving and pillar and top coal extraction for mining thick coal seams includes the advance mining of rooms and crosscuts along the bottom of a seam to a height of about eight feet, and the retreat mining of the top coal from the rooms, crosscuts and portions of the pillars remaining from formation of the rooms and cross-cuts. In the retreat mining, a pocket is formed in a pillar, the top coal above the pocket is drilled, charged and shot, and then the fallen coal is loaded by a continuous miner so that the operator remains under a roof which has not been shot. The top coal from that portion of the room adjacent the pocket is then mined, and another pocket is formed in the pillar. The top coal above the second pocket is mined followed by the mining of the top coal of that portion of the room adjacent the second pocket, all by use of a continuous miner which allows the operator to remain under a roof portion which has not been shot.

A moving baseline for evaluation of advanced coal extraction systems

NASA Technical Reports Server (NTRS)

Bickerton, C. R.; Westerfield, M. D.

1981-01-01

Results from the initial effort to establish baseline economic performance comparators for a program whose intent is to define, develop, and demonstrate advanced systems suitable for coal resource extraction beyond the year 2000 are reported. Systems used were selected from contemporary coal mining technology and from conservation conjectures of year 2000 technology. The analysis was also based on a seam thickness of 6 ft. Therefore, the results are specific to the study systems and the selected seam extended to other seam thicknesses.

Robotic complex for the development of thick steeply-inclined coal seams and ore deposits

NASA Astrophysics Data System (ADS)

Nikitenko, M. S.; Malakhov, Yu V.; Neogi, Biswarup; Chakraborty, Pritam; Banerjee, Dipesu

2017-09-01

Proposal for the formulation of robotic complexes for steeply inclined coal seams as a basis of the supportive-enclosing walking module and power support with a controlled outlet for mining industry has been represented in this literature. In mining industry, the available resource base reserves and mineral deposits are concentrated deep down the earth crust leading towards a complicated geological condition i.e. abrupt ore bedding and steeply inclined strata with the high gas content and fire hazard of thick coal stratum, heading against an unfavorable and sometimes human labor life risk during subversive mining. Prevailing towards the development of effective robotic complexes based on the means of “unmanned technologies” for extraction of minerals from hard-to-reach deposits and make sure the safety of underground staff during sublevel mining technology.

78 FR 7458 - Petitions for Modification of Application of Existing Mandatory Safety Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2013-02-01

.... Petitioner: Sterling Mining Corporation, P.O. Box 217, North Lima, Ohio 44452. Mines: Shean Hill, MSHA I.D... outlets and valves. 6. Due to the thin coal seam and low mining height, the pipes placed along the roof... Granules (Ione) LLC, 1101 Opal Court, Suite 315, Hagerstown, Maryland 21740. Mine: Ione Mine, MSHA I.D. No...

Teleoperated control system for underground room and pillar mining

DOEpatents

Mayercheck, William D.; Kwitowski, August J.; Brautigam, Albert L.; Mueller, Brian K.

1992-01-01

A teleoperated mining system is provided for remotely controlling the various machines involved with thin seam mining. A thin seam continuous miner located at a mining face includes a camera mounted thereon and a slave computer for controlling the miner and the camera. A plurality of sensors for relaying information about the miner and the face to the slave computer. A slave computer controlled ventilation sub-system which removes combustible material from the mining face. A haulage sub-system removes material mined by the continuous miner from the mining face to a collection site and is also controlled by the slave computer. A base station, which controls the supply of power and water to the continuous miner, haulage system, and ventilation systems, includes cable/hose handling module for winding or unwinding cables/hoses connected to the miner, an operator control module, and a hydraulic power and air compressor module for supplying air to the miner. An operator controlled host computer housed in the operator control module is connected to the slave computer via a two wire communications line.

Influences Determining European Coal Seam Gas Deliverability

NASA Astrophysics Data System (ADS)

Clark, G.

2009-04-01

Technically the coal basins of Europe have generated significant Gas In Place figures that has historically generated investor's interest in the development of this potential coal seam gas (CSG) resource. In the early 1980's, a wave of international, principally American, companies arrived, established themselves, drilled and then left with a poor record of success and disappointed investors. Recently a second wave of investment started after 2002, with the smaller companies leading the charge but have the lesson been learned from the past failures? To select a CSG investment project the common European approach has been to: 1. Find an old mining region; 2. Look to see if it had a coal mine methane gas problem; 3. Look for the non-mined coal seams; and 4. Peg the land. This method is perhaps the reason why the history of CSG exploration in Europe is such a disappointment as generally the coal mining regions of Europe do not have commercial CSG reservoir attributes. As a result, investors and governments have lost confidence that CSG will be a commercial success in Europe. New European specific principles for the determination of commercial CSG prospects have had to be delineated that allow for the selection of coal basins that have a strong technical case for deliverability. This will result in the return of investor confidence.

Detecting voids in a 0.6 m coal seam, 7 m deep, using seismic reflection

USGS Publications Warehouse

Miller, R.D.; Steeples, D.W.

1991-01-01

Surface collapse over abandoned subsurface coal mines is a problem in many parts of the world. High-resolution P-wave reflection seismology was successfully used to evaluate the risk of an active sinkhole to a main north-south railroad line in an undermined area of southeastern Kansas, USA. Water-filled cavities responsible for sinkholes in this area are in a 0.6 m thick coal seam, 7 m deep. Dominant reflection frequencies in excess of 200 Hz enabled reflections from the coal seam to be discerned from the direct wave, refractions, air wave, and ground roll on unprocessed field files. Repetitive void sequences within competent coal on three seismic profiles are consistent with the "room and pillar" mining technique practiced in this area near the turn of the century. The seismic survey showed that the apparent active sinkhole was not the result of reactivated subsidence but probably erosion. ?? 1991.

Hydrology of the North Fork of the Right Fork of Miller Creek, Carbon County, Utah, before, during, and after underground coal mining

USGS Publications Warehouse

Slaughter, C.B.; Freethey, G.W.; Spangler, L.E.

1995-01-01

From 1988-92 the U.S. Geological Survey, in cooperation with the Utah Division of Oil, Gas, and Mining, studied the effects of underground coal mining and the resulting subsidence on the hydrologic system near the North Fork of the Right Fork of Miller Creek, Carbon County, Utah. The subsidence caused open fractures at land surface, debris slides, and rockfalls in the canyon above the mined area. Land surface subsided and moved several feet horizontally. The perennial stream and a tributary upstream from the mined area were diverted below the ground by surface fractures where the overburden thickness above the Wattis coal seam is 300 to 500 feet. The reach downstream was dry but flow resumed where the channel traversed the Star Point Sandstone, which forms the aquifer below the coal seams where ground-water discharge provides new base flow. Concentrations of dissolved constituents in the stream water sampled just downstream from the mined area increased from about 300 mg/L (milligrams per liter) to more than 1,500 mg/L, and the water changed from primarily a magnesium calcium bicarbonate to primarily a magnesium sulfate type. Monitored water levels in two wells completed in the perched aquifer(s) above the mine indicate that fractures from subsidence- related deformation drained the perched aquifer in the Blackhawk Formation. The deformation also could have contributed to the decrease in discharge of three springs above the mined area, but discharge from other springs in the area did not change ubstantially; thus, the relation between subsidence and spring discharge, if any, is not clear. No significant changes in the chemical character of water discharging from springs were detected, but the dissolved-solids concentration in water collected from a perched sandstone aquifer overlying the mined coal seams increased during mining activity.

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

NASA Astrophysics Data System (ADS)

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.

Vertical-Control Subsystem for Automatic Coal Mining

NASA Technical Reports Server (NTRS)

Griffiths, W. R.; Smirlock, M.; Aplin, J.; Fish, R. B.; Fish, D.

1984-01-01

Guidance and control system automatically positions cutting drums of double-ended longwall shearer so they follow coal seam. System determines location of upper interface between coal and shale and continuously adjusts cutting-drum positions, upward or downward, to track undulating interface. Objective to keep cutting edges as close as practicable to interface and thus extract as much coal as possible from seam.

77 FR 50166 - Petitions for Modification of Application of Existing Mandatory Safety Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-20

... less than one shot per 10 feet to permit expanding cement to infiltrate the annulus between the casing... mineable coal seam will be perforated with one shot at the elevation of each coal seam above the lowest... detected. The record will be retained at the mine for one year. The petitioner asserts that the proposed...

Knight Hawk adapts highwall mining for Southern Illinois

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buchsbaum, L.

2007-10-15

A few years ago while planning their first underground operation and trying to decide how to mine shallow seams, Knight Hawk purchased a 'Superior Highwall Miner' (SHM). Since then this small innovative company has been pioneering the use of highwall mining in a trenching application in for example the Illinois Basin. Highwall mining is very suitable for contour mining in Appalachia. The article discusses the recent improvements and the advantages of SHM mining systems. 3 photos.

Underground mineral extraction

NASA Technical Reports Server (NTRS)

Miller, C. G.; Stephens, J. B.

1980-01-01

A method was developed for extracting underground minerals such as coal, which avoids the need for sending personnel underground and which enables the mining of steeply pitched seams of the mineral. The method includes the use of a narrow vehicle which moves underground along the mineral seam and which is connected by pipes or hoses to water pumps at the surface of the Earth. The vehicle hydraulically drills pilot holes during its entrances into the seam, and then directs sideward jets at the seam during its withdrawal from each pilot hole to comminute the mineral surrounding the pilot hole and combine it with water into a slurry, so that the slurried mineral can flow to a location where a pump raises the slurry to the surface.

78 FR 52967 - Notice of Intent To Initiate Public Scoping and Prepare an Environmental Impact Statement for...

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-27

... acres (4,287 acres would be disturbed by the mining operations, highwall reduction, soil storage, scoria... WECo currently uses in other permitted areas of the Rosebud Mine. In advance of each mining pass, soil... expose the coal seam. Overburden stockpiles, soil stockpiles, and scoria pits would be developed adjacent...

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

USGS Publications Warehouse

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 change up to 3. MMscf per acre and, in a multi-panel district, may total 9. Bcf of methane within the gas emission zone. Therefore, ventilation and gas capture systems should be designed accordingly. In addition, rock displacements within the gas emission zone are spatially distributed. From an engineering and practical point of view, spatial distributions of GIP and distributions of rock displacements should be correlated with in-mine emissions and gob gas venthole productions. ?? 2011.

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

PubMed Central

Karacan, C. Özgen; Olea, Ricardo A.; Goodman, Gerrit

2015-01-01

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 change up to 3 MMscf per acre and, in a multi-panel district, may total 9 Bcf of methane within the gas emission zone. Therefore, ventilation and gas capture systems should be designed accordingly. In addition, rock displacements within the gas emission zone are spatially distributed. From an engineering and practical point of view, spatial distributions of GIP and distributions of rock displacements should be correlated with in-mine emissions and gob gas venthole productions. PMID:26435558

Mine Water Treatment in Hongai Coal Mines

NASA Astrophysics Data System (ADS)

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.

Sensitivity Analysis of Mechanical Parameters of Different Rock Layers to the Stability of Coal Roadway in Soft Rock Strata

PubMed Central

Zhao, Zeng-hui; Wang, Wei-ming; Gao, Xin; Yan, Ji-xing

2013-01-01

According to the geological characteristics of Xinjiang Ili mine in western area of China, a physical model of interstratified strata composed of soft rock and hard coal seam was established. Selecting the tunnel position, deformation modulus, and strength parameters of each layer as influencing factors, the sensitivity coefficient of roadway deformation to each parameter was firstly analyzed based on a Mohr-Columb strain softening model and nonlinear elastic-plastic finite element analysis. Then the effect laws of influencing factors which showed high sensitivity were further discussed. Finally, a regression model for the relationship between roadway displacements and multifactors was obtained by equivalent linear regression under multiple factors. The results show that the roadway deformation is highly sensitive to the depth of coal seam under the floor which should be considered in the layout of coal roadway; deformation modulus and strength of coal seam and floor have a great influence on the global stability of tunnel; on the contrary, roadway deformation is not sensitive to the mechanical parameters of soft roof; roadway deformation under random combinations of multi-factors can be deduced by the regression model. These conclusions provide theoretical significance to the arrangement and stability maintenance of coal roadway. PMID:24459447

Effect of Water Invasion on Outburst Predictive Index of Low Rank Coals in Dalong Mine

PubMed Central

Jiang, Jingyu; Cheng, Yuanping; Mou, Junhui; Jin, Kan; Cui, Jie

2015-01-01

To improve the coal permeability and outburst prevention, coal seam water injection and a series of outburst prevention measures were tested in outburst coal mines. These methods have become important technologies used for coal and gas outburst prevention and control by increasing the external moisture of coal or decreasing the stress of coal seam and changing the coal pore structure and gas desorption speed. In addition, techniques have had a significant impact on the gas extraction and outburst prevention indicators of coal seams. Globally, low rank coals reservoirs account for nearly half of hidden coal reserves and the most obvious feature of low rank coal is the high natural moisture content. Moisture will restrain the gas desorption and will affect the gas extraction and accuracy of the outburst prediction of coals. To study the influence of injected water on methane desorption dynamic characteristics and the outburst predictive index of coal, coal samples were collected from the Dalong Mine. The methane adsorption/desorption test was conducted on coal samples under conditions of different injected water contents. Selective analysis assessed the variations of the gas desorption quantities and the outburst prediction index (coal cutting desorption index). Adsorption tests indicated that the Langmuir volume of the Dalong coal sample is ~40.26 m3/t, indicating a strong gas adsorption ability. With the increase of injected water content, the gas desorption amount of the coal samples decreased under the same pressure and temperature. Higher moisture content lowered the accumulation desorption quantity after 120 minutes. The gas desorption volumes and moisture content conformed to a logarithmic relationship. After moisture correction, we obtained the long-flame coal outburst prediction (cutting desorption) index critical value. This value can provide a theoretical basis for outburst prediction and prevention of low rank coal mines and similar occurrence conditions of coal seams. PMID:26161959

43 CFR 3930.13 - Performance standards for surface mines.

Code of Federal Regulations, 2011 CFR

2011-10-01

... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR RANGE MANAGEMENT (4000) MANAGEMENT OF OIL SHALE EXPLORATION AND LEASES Management of Oil Shale Exploration Licenses and Leases § 3930.13 Performance standards for surface mines. (a) Pit widths for each oil shale seam must be engineered and designed to eliminate...

43 CFR 3930.13 - Performance standards for surface mines.

Code of Federal Regulations, 2013 CFR

2013-10-01

... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MANAGEMENT OF OIL SHALE EXPLORATION AND LEASES Management of Oil Shale Exploration Licenses and Leases § 3930.13 Performance standards for surface mines. (a) Pit widths for each oil shale seam must be engineered and designed to eliminate...

43 CFR 3930.13 - Performance standards for surface mines.

Code of Federal Regulations, 2012 CFR

2012-10-01

... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MANAGEMENT OF OIL SHALE EXPLORATION AND LEASES Management of Oil Shale Exploration Licenses and Leases § 3930.13 Performance standards for surface mines. (a) Pit widths for each oil shale seam must be engineered and designed to eliminate...

43 CFR 3930.13 - Performance standards for surface mines.

Code of Federal Regulations, 2014 CFR

2014-10-01

... OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MANAGEMENT OF OIL SHALE EXPLORATION AND LEASES Management of Oil Shale Exploration Licenses and Leases § 3930.13 Performance standards for surface mines. (a) Pit widths for each oil shale seam must be engineered and designed to eliminate...

30 CFR 75.1315 - Boreholes for explosives.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND... thickness of the coal seam. (c) Each borehole in rock for explosives shall be at least 18 inches from any...

30 CFR 75.1315 - Boreholes for explosives.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND... thickness of the coal seam. (c) Each borehole in rock for explosives shall be at least 18 inches from any...

30 CFR 75.1315 - Boreholes for explosives.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND... thickness of the coal seam. (c) Each borehole in rock for explosives shall be at least 18 inches from any...

30 CFR 75.1315 - Boreholes for explosives.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND... thickness of the coal seam. (c) Each borehole in rock for explosives shall be at least 18 inches from any...

30 CFR 75.1315 - Boreholes for explosives.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Boreholes for explosives. 75.1315 Section 75.1315 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR COAL MINE SAFETY AND... thickness of the coal seam. (c) Each borehole in rock for explosives shall be at least 18 inches from any...

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

NASA Astrophysics Data System (ADS)

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).

Analysis of coal seam thickness and seismic wave amplitude: A wedge model

NASA Astrophysics Data System (ADS)

Zou, Guangui; Xu, Zhiliang; Peng, Suping; Fan, Feng

2018-01-01

Coal seam thickness is of great significance in mining coal resources. The focus of this study is to determine the relationship between coal seam thickness and seismic wave amplitude, and the factors influencing this relationship. We used a wedge model to analyze this relationship and its influencing factors. The results show that wave interference from the top and bottom interfaces is the primary reason for the linear relationship between seismic wave amplitude and wedge thickness, when the thickness of the wedge is less than one quarter of the wavelength. This relationship is influenced by the dominant frequency, reflection coefficients from the top and bottom boundaries, depth, thickness, and angle of the wedge. However, when the lateral shift between the reflected waves is smaller than the radius of the first Fresnel zone, the wedge angle and change in lithology at the top and bottom layers are considered to have little effect on the amplitude of the interference wave. The difference in the dominant frequency of seismic waves can be reduced by filtering, and the linear relationship between amplitude and coal thickness can be improved. Field data from Sihe coal mine was analyzed, and the error was found to be within 4% of the predicted seismic wave amplitude. The above conclusions could help predict the thickness of coal seam by seismic amplitude.

Analyses of geological and hydrodynamic controls on methane emissions experienced in a Lower Kittanning coal mine

PubMed Central

Karacan, C. Özgen; Goodman, Gerrit V.R.

2015-01-01

This paper presents a study assessing potential factors and migration paths of methane emissions experienced in a room-and-pillar mine in Lower Kittanning coal, Indiana County, Pennsylvania. Methane emissions were not excessive at idle mining areas, but significant methane was measured during coal mining and loading. Although methane concentrations in the mine did not exceed 1% limit during operation due to the presence of adequate dilution airflow, the source of methane and its migration into the mine was still a concern. In the course of this study, structural and depositional properties of the area were evaluated to assess complexity and sealing capacity of roof rocks. Composition, gas content, and permeability of Lower Kittanning coal, results of flotation tests, and geochemistry of groundwater obtained from observation boreholes were studied to understand the properties of coal and potential effects of old abandoned mines within the same area. These data were combined with the data obtained from exploration boreholes, such as depths, elevations, thicknesses, ash content, and heat value of coal. Univariate statistical and principal component analyses (PCA), as well as geostatistical simulations and co-simulations, were performed on various spatial attributes to reveal interrelationships and to establish area-wide distributions. These studies helped in analyzing groundwater quality and determining gas-in-place (GIP) of the Lower Kittanning seam. Furthermore, groundwater level and head on the Lower Kittanning coal were modeled and flow gradients within the study area were examined. Modeling results were interpreted with the structural geology of the Allegheny Group of formations above the Lower Kittanning coal to understand the potential source of gas and its migration paths. Analyses suggested that the source of methane was likely the overlying seams such as the Middle and Upper Kittanning coals and Freeport seams of the Allegheny Group. Simulated ground-water water elevations, gradients of groundwater flow, and the presence of recharge and discharge locations at very close proximity to the mine indicated that methane likely was carried with groundwater towards the mine entries. Existing fractures within the overlying strata and their orientation due to the geologic conditions of the area, and activation of slickensides between shale and sandstones due to differential compaction during mining, were interpreted as the potential flow paths. PMID:26478644

Hydrogeology, groundwater flow, and groundwater quality of an abandoned underground coal-mine aquifer, Elkhorn Area, West Virginia

USGS Publications Warehouse

Kozar, Mark D.; McCoy, Kurt J.; Britton, James Q.; Blake, B.M.

2017-01-01

The Pocahontas No. 3 coal seam in southern West Virginia has been extensively mined by underground methods since the 1880’s. An extensive network of abandoned mine entries in the Pocahontas No. 3 has since filled with good-quality water, which is pumped from wells or springs discharging from mine portals (adits), and used as a source of water for public supplies. This report presents results of a three-year investigation of the geology, hydrology, geochemistry, and groundwater flow processes within abandoned underground coal mines used as a source of water for public supply in the Elkhorn area, McDowell County, West Virginia. This study focused on large (> 500 gallon per minute) discharges from the abandoned mines used as public supplies near Elkhorn, West Virginia. Median recharge calculated from base-flow recession of streamflow at Johns Knob Branch and 12 other streamflow gaging stations in McDowell County was 9.1 inches per year. Using drainage area versus mean streamflow relationships from mined and unmined watersheds in McDowell County, the subsurface area along dip of the Pocahontas No. 3 coal-mine aquifer contributing flow to the Turkey Gap mine discharge was determined to be 7.62 square miles (mi2), almost 10 times larger than the 0.81 mi2 surface watershed. Results of this investigation indicate that groundwater flows down dip beneath surface drainage divides from areas up to six miles east in the adjacent Bluestone River watershed. A conceptual model was developed that consisted of a stacked sequence of perched aquifers, controlled by stress-relief and subsidence fractures, overlying a highly permeable abandoned underground coal-mine aquifer, capable of substantial interbasin transfer of water. Groundwater-flow directions are controlled by the dip of the Pocahontas No. 3 coal seam, the geometry of abandoned mine workings, and location of unmined barriers within that seam, rather than surface topography. Seven boreholes were drilled to intersect abandoned mine workings in the Pocahontas No. 3 coal seam and underlying strata in various structural settings of the Turkey Gap and adjacent down-dip mines. Geophysical logging and aquifer testing were conducted on the boreholes to locate the coal- mine aquifers, characterize fracture geometry, and define permeable zones within strata overlying and underlying the Pocahontas No. 3 coal-mine aquifer. Water levels were measured monthly in the wells and showed a relatively static phreatic zone within subsided strata a few feet above the top of or within the Pocahontas No. 3 coal-mine aquifer (PC3MA). A groundwater-flow model was developed to verify and refine the conceptual understanding of groundwater flow and to develop groundwater budgets for the study area. The model consisted of four layers to represent overburden strata, the Pocahontas No. 3 coal-mine aquifer, underlying fractured rock, and fractured rock below regional drainage. Simulation of flow in the flooded abandoned mine entries using highly conductive layers or zones within the model, was unable to realistically simulate interbasin transfer of water. Therefore it was necessary to represent the coal-mine aquifer as an internal boundary condition rather than a contrast in aquifer properties. By representing the coal-mine aquifer with a series of drain nodes and optimizing input parameters with parameter estimation software, model errors were reduced dramatically and discharges for Elkhorn Creek, Johns Knob Branch, and other tributaries were more accurately simulated. Flow in the Elkhorn Creek and Johns Knob Branch watersheds is dependent on interbasin transfer of water, primarily from up dip areas of abandoned mine workings in the Pocahontas No. 3 coal-mine aquifer within the Bluestone River watershed to the east. For the 38th, 70th, and 87th percentile flow duration of streams in the region, mean measured groundwater discharge was estimated to be 1.30, 0.47, and 0.39 cubic feet per square mile (ft3/s/mi2

Impacts of Coal Seam Gas (Coal Bed Methane) Extraction on Water Resources in Australia

NASA Astrophysics Data System (ADS)

Post, David

2017-04-01

While extraction of methane from shale gas deposits has been the principal source of the recent expansion of the industry in the United States, in Australia extraction of methane from coal bed methane deposits (termed 'coal seam gas' in Australia) has been the focus to date. The two sources of methane share many of the same characteristics including the potential requirement for hydraulic fracturing. However, as coal seam gas deposits generally occur at shallower depths than shale gas, the potential impacts of extraction on surface and groundwater resources may be of even greater concern. In Australia, an Independent Expert Scientific Committee (IESC) has been established to provide scientific advice to federal and state government regulators on the impact that coal seam gas and large coal mining developments may have on water resources. This advice is provided to enable decisions to be informed by the best available science about the potential water-related impacts associated with these developments. To support this advice, the Australian Government Department of the Environment has implemented a programme of research termed 'bioregional assessments' to investigate these potential impacts. A bioregional assessment is defined as a scientific analysis of the ecology, hydrology, geology and hydrogeology of a bioregion with explicit assessment of the potential direct, indirect and cumulative impacts of coal seam gas and large coal mining development on water resources. These bioregional assessments are currently being carried out across large portions of eastern Australia underlain by coal reserves. Further details of the programme and results to date can be found at http://www.bioregionalassessments.gov.au. The bioregional assessment programme has modelled the impacts of coal seam gas development on surface and groundwater resources in three regions of eastern Australia, namely the Clarence-Moreton, Gloucester, and Namoi regions. This presentation will discuss the overall approach taken, and discuss how the results of these modelling studies will be used to evaluate the impacts of the depressurisation of coal seams on ecological, economic and socio-cultural assets that are dependent on surface and/or groundwater.

Impacts of Coal Seam Gas (Coal Bed Methane) Extraction on Water Resources in Australia

NASA Astrophysics Data System (ADS)

Post, David

2016-04-01

While extraction of methane from shale gas deposits has been the principal source of the recent expansion of the industry in the United States and Europe, in Australia extraction of methane from coal bed methane deposits (termed 'coal seam gas' in Australia) has been the focus to date. The two sources of methane share many of the same characteristics including the potential requirement for hydraulic fracturing. However, as coal seam gas deposits generally occur at shallower depths than shale gas, the potential impacts of extraction on surface and groundwater resources may be of even greater concern. In Australia, an Independent Expert Scientific Committee (IESC) has been established to provide scientific advice to federal and state government regulators on the impact that coal seam gas and large coal mining developments may have on water resources. This advice is provided to enable decisions to be informed by the best available science about the potential water-related impacts associated with these developments. To support this advice, the Australian Government Department of the Environment has implemented a programme of research termed 'bioregional assessments' to investigate these potential impacts. A bioregional assessment is defined as a scientific analysis of the ecology, hydrology, geology and hydrogeology of a bioregion with explicit assessment of the potential direct, indirect and cumulative impacts of coal seam gas and large coal mining development on water resources. These bioregional assessments are currently being carried out across large portions of eastern Australia underlain by coal reserves. Further details of the programme and results to date can be found at http://www.bioregionalassessments.gov.au. Surface water and groundwater modelling is now complete for two regions where coal seam gas development may proceed, namely the Clarence-Moreton and Gloucester regions in eastern New South Wales. This presentation will discuss how the results of these modelling studies will be used to evaluate the impacts of the depressurisation of coal seams on ecological, economic and socio-cultural assets that are dependent on surface water and/or groundwater.

Impacts of Coal Seam Gas (Coal Bed Methane) Extraction on Water Resources in Australia

NASA Astrophysics Data System (ADS)

Post, David

2015-04-01

While extraction of methane from shale gas deposits has been the principal source of the recent expansion of the industry in the United States and Europe, in Australia extraction of methane from coal bed methane deposits (termed 'coal seam gas' in Australia) has been the focus to date. The two sources of methane share many of the same characteristics including the potential requirement for hydraulic fracturing. However as coal seam gas deposits generally occur at shallower depths than shale gas the potential impacts of extraction and hydraulic fracturing on surface and groundwater resources may be of even greater concern for coal seam gas than for shale gas. In Australia an Independent Expert Scientific Committee (IESC) has been established to provide scientific advice to federal and state government regulators on the impact that coal seam gas and large coal mining developments may have on water resources. This advice is provided to enable decisions to be informed by the best available science about the potential water-related impacts associated with these developments. To support this advice the Australian Government Department of the Environment has implemented a three-year programme of research termed 'bioregional assessments' to investigate these potential impacts. A bioregional assessment is defined as a scientific analysis of the ecology, hydrology, geology and hydrogeology of a bioregion with explicit assessment of the potential direct, indirect and cumulative impacts of coal seam gas and large coal mining development on water resources. These bioregional assessments are currently being carried out across large portions of eastern Australia underlain by coal reserves. Further details of the program and results to date can be found at http://www.bioregionalassessments.gov.au. In this presentation the methodology for undertaking bioregional assessments will be described and the application of this methodology to six priority bioregions in eastern Australia will be detailed. Results of the programme to date will be provided (being nearly two years into the three-year study) with a focus on the preliminary results of numerical groundwater modelling. Once completed this modelling will be used to evaluate the impacts of the depressurisation of coal seams on aquifers and associated ecological, economic and socio-cultural water-dependent assets.

Hydraulic characteristics of, and ground-water flow in, coal-bearing rocks of southwestern Virginia

USGS Publications Warehouse

Harlow, George E.; LeCain, Gary D.

1993-01-01

This report presents the results of a study by the U.S Geological Survey, in cooperation with the Virginia Department of Mines, Minerals, and Energy, Division of Mined Land Reclamation, and the Powell River Project, to describe the hydraulic characteristics of major water-bearing zones in the coal-bearing rocks of southwestern Virginia and to develop a conceptual model of the ground-water-flow system. Aquifer testing in1987 and 1988 of 9-ft intervals in coal-exploration coreholes indicates that transmissivity decreases with increasing depth. Most rock types are permeable to a depth of approximately 100 ft; however, only coal seams are consistently permeable (transmissivity greater than 0.001 ft/d) at depths greater than 200 ft . Constant-head injection testing of rock intervals adjacent to coal seams usually indicated lower values of transmissivity than those values obtained when coal seams were isolated within the test interval; thus, large values of horizontal hydraulic conductivity at depth are associated with coal seams. Potentiometric-head measurements indicate that high topographic areas (ridges) function as recharge areas; water infiltrates through the surface, percolates into regolith, and flows downward and laterally through fractures in the shallow bedrock. Hydraulic conductivity decreases with increasing depth, and ground water flows primarily in the lateral direction along fractures or bedding planes or through coal seams. If vertical hydraulic conductivity is negligible, ground water continues to flow laterally, discharging as springs or seeps on hill slopes. Where vertical hydraulic conductivity is appreciable, groundwater follows a stair step path through the regolith, fractures, bedding planes, and coal seams, discharging to streams and (or) recharging coal seams at depth. Permeable coal seams probably underlie valleys in the region; however, aquifer-test data indicate that the horizontal hydraulic conductivity of coal is a function of depth and probably decreases under ridges because of increased overburden pressures. Ground water beneath valleys that does not discharge to streams probably flows down gradient as underflow beneath the streams. Topographic relief in the area provides large hydraulic-head differences (greater than 300 ft in some instances) for the ground-water-flow system. Transmissivity data from the range of depths tested during this study indicate that most ground-water flow takes place at moderate depths (less than 300 ft) and that little deep regional ground-water flow occurs.

Electrical Resistivity Tomography for coal fire mapping over Jharia coal field, India

NASA Astrophysics Data System (ADS)

Pal, S. K.; Kumar, S.; Bharti, A. K.; Pathak, V. K.; Kumar, R.

2016-12-01

Over the decades, coal fires are serious global concern posing grievous hazards to the valuable energy resources, local environments and human life. The coal seam and coal mine fires may be initiated due to improper mining activities, exothermic reactions, lighting, forest fire and other anthropic activities, which burn the coal and may continue underground for decades. The burning of concealed coal seams is a complex process involving numerous ill-defined parameters. Generally, the coal exhibits resistivity of 100 to 500Ωm at normal temperature conditions. During the pyrolysis process, at temperatures greater than 6500C coal became a good conductor with a resistivity of approximately 1 Ωm. The present study deals with the mapping of coal fire over Jharia coal field, India using Electrical Resistivity Tomography (ERT). A state-of-the-art 61-channel 64 electrode FlashRES-Universal ERT data acquisition system has been used for data acquisition in the field. The ERT data have been collected using Gradient array and processed in FlashRES Universal survey data checking program for removing noisy data. Then, filtered output data have been inverted using a 2.5D resistivity inversion program. Low resistivity anomalies over 80m-125m and 320m-390m along the profile are inferred to be active coal fire in seam- XVI at a depth of 25m -35m(Figure 1). High resistivity anomaly over 445m - 510m at a depth of 25m -35m has been delineated, due to void associated with complete combustion of seam- XVI coal, followed by char and ash formation resulting from the coal seam fire. Results prove the efficacy of the ERT study comprising Gradient array for coal fire mapping over, Jharia coal field, India.

The Mine Working's Roof Stress-strain State Research in the Perspective of Development of New Coal Deposits of Kuzbass

NASA Astrophysics Data System (ADS)

Kostyuk, Svetlana; Bedarev, Nikolay; Lyubimov, Oleg; Shaikhislamov, Arthur

2017-11-01

The present now normative and information base is regulating of the Kuzbass coal seams treatment but is not considering of the mining-geological and mining-engineering conditions for new coal deposits. The analysis of works for the research of the rock pressure manifestation shows that in many cases numerous results require of the practical confirmation in mine conditions directly, and also confirmation by the physical models. This work reflects one of the stages of research on changing the stress-strain state of the massif with the formation of unloading zones, increased rock pressure, and recovery. As an example, the results of the information analysis obtained by means of contour and depth benchmarks on the ventilation drift in the course of the 34 seam treatment at the "Tagaryshskaya" mine are presented. The differences of the analyzed results from the results obtained in the conditions of other mines are established. The values of the drift's roof stratification on the contour and at the distance from the contour of 1.0 to 4.0 m are given. The revealed maximums of the rock pressure and pressure changes in the hydraulic supports of the complex used for movement are presented. Recommendations on the choice of the anchor's length taking into account the roof stratification size are given. The further research stages on models from equivalent materials at various geometric scales are proposed.

Automated Coal-Mining System

NASA Technical Reports Server (NTRS)

Gangal, M. D.; Isenberg, L.; Lewis, E. V.

1985-01-01

Proposed system offers safety and large return on investment. System, operating by year 2000, employs machines and processes based on proven principles. According to concept, line of parallel machines, connected in groups of four to service modules, attacks face of coal seam. High-pressure water jets and central auger on each machine break face. Jaws scoop up coal chunks, and auger grinds them and forces fragments into slurry-transport system. Slurry pumped through pipeline to point of use. Concept for highly automated coal-mining system increases productivity, makes mining safer, and protects health of mine workers.

Hybrid Technology of Hard Coal Mining from Seams Located at Great Depths

NASA Astrophysics Data System (ADS)

Czaja, Piotr; Kamiński, Paweł; Klich, Jerzy; Tajduś, Antoni

2014-10-01

Learning to control fire changed the life of man considerably. Learning to convert the energy derived from combustion of coal or hydrocarbons into another type of energy, such as steam pressure or electricity, has put him on the path of scientific and technological revolution, stimulating dynamic development. Since the dawn of time, fossil fuels have been serving as the mankind's natural reservoir of energy in an increasingly great capacity. A completely incomprehensible refusal to use fossil fuels causes some local populations, who do not possess a comprehensive knowledge of the subject, to protest and even generate social conflicts as an expression of their dislike for the extraction of minerals. Our times are marked by the search for more efficient ways of utilizing fossil fuels by introducing non-conventional technologies of exploiting conventional energy sources. During apartheid, South Africa demonstrated that cheap coal can easily satisfy total demand for liquid and gaseous fuels. In consideration of current high prices of hydrocarbon media (oil and gas), gasification or liquefaction of coal seems to be the innovative technology convergent with contemporary expectations of both energy producers as well as environmentalists. Known mainly from literature reports, underground coal gasification technologies can be brought down to two basic methods: - shaftless method - drilling, in which the gasified seam is uncovered using boreholes drilled from the surface, - shaft method, in which the existing infrastructure of underground mines is used to uncover the seams. This paper presents a hybrid shaft-drilling approach to the acquisition of primary energy carriers (methane and syngas) from coal seams located at great depths. A major advantage of this method is the fact that the use of conventional coal mining technology requires the seams located at great depths to be placed on the off-balance sheet, while the hybrid method of underground gasification enables them to become a source of additional energy for the economy. It should be noted, however, that the shaft-drilling method cannot be considered as an alternative to conventional methods of coal extraction, but rather as a complementary and cheaper way of utilizing resources located almost beyond the technical capabilities of conventional extraction methods due to the associated natural hazards and high costs of combating them. This article presents a completely different approach to the issue of underground coal gasification. Repurposing of the already fully depreciated mining infrastructure for the gasification process may result in a large value added of synthesis gas production and very positive economic effect.

Research on solvent-refined coal. Quarterly technical progress report, April 1, 1981-June 30, 1981

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-10-01

This report describes progress on the Research on Solvent Refined Coal project by The Pittsburg and Midway Coal Mining Co.'s Merriam Laboratory during the second quarter of 1981. Alexander Mine coal was evaluated as a feedstock for major liquefaction facilities and had a yield structure similar to other reactive Pittsburgh seam coals at standard SRC II conditions. Two lots of coal from the Ireland Mine (Pittsburgh seam) were found to be of nearly the same composition and produced essentially the same yields. Two experiments in which coal-derived nonvolatile organic matter was processed without fresh coal feed indicate constant rates ofmore » conversion of SRC to oil and gas. Insoluble organic matter (IOM) remained unconverted. The naphtha and middle distillate products from the deep conversion contained less sulfur but more nitrogen than those from conventional SRC II processing. Encouraging results were obtained when a very small amount of iron oxide dispersed on alumina was added to Kaiparowits coal which cannot be processed at normal SRC II conditions without added catalyst. Subbituminous coals from the McKinley and Edna Mines were processed successfully with added pyrite but would not run when the added catalyst was removed.« less

Economic baselines for current underground coal mining technology

NASA Technical Reports Server (NTRS)

Mabe, W. B.

1979-01-01

The cost of mining coal using a room pillar mining method with continuous miner and a longwall mining system was calculated. Costs were calculated for the years 1975 and 2000 time periods and are to be used as economic standards against which advanced mining concepts and systems will be compared. Some assumptions were changed and some internal model stored data was altered from the original calculations procedure chosen, to obtain a result that more closely represented what was considered to be a standard mine. Coal seam thicknesses were varied from one and one-half feet to eight feet to obtain the cost of mining coal over a wide range. Geologic conditions were selected that had a minimum impact on the mining productivity.

A novel method for estimating methane emissions from underground coal mines: The Yanma coal mine, China

NASA Astrophysics Data System (ADS)

Ji, Zhong-Min; Chen, Zhi-Jian; Pan, Jie-Nan; Niu, Qing-He

2017-12-01

As the world's largest coal producer and consumer, China accounts for a relatively high proportion of methane emissions from coal mines. Several estimation methods had been established for the coal mine methane (CMM) emission. However, with large regional differences, various reservoir formation types of coalbed methane (CBM) and due to the complicated geological conditions in China, these methods may be deficient or unsuitable for all the mining areas (e.g. Jiaozuo mining area). By combing the CMM emission characteristics and considering the actual situation of methane emissions from underground coal mine, we found that the methane pre-drainage is a crucial reason creating inaccurate evaluating results for most estimation methods. What makes it so essential is the extensive pre-drainage quantity and its irrelevance with annual coal production. Accordingly, the methane releases were divided into two categories: methane pre-drainage and methane release during mining. On this basis, a pioneering method for estimating CMM emissions was proposed. Taking the Yanma coal mine in the Jiaozuo mining area as a study case, the evaluation method of the pre-drainage methane quantity was established after the correlation analysis between the pre-drainage rate and time. Thereafter, the mining activity influence factor (MAIF) was first introduced to reflect the methane release from the coal and rock seams around where affected by mining activity, and the buried depth was adopted as the predictor of the estimation for future methane emissions. It was verified in the six coal mines of Jiaozuo coalfield (2011) that the new estimation method has the minimum errors of 12.11%, 9.23%, 5.77%, -5.20%, -8.75% and 4.92% respectively comparing with other methods. This paper gives a further insight and proposes a more accurate evaluation method for the CMM emissions, especially for the coal seams with low permeability and strong tectonic deformation in methane outburst coal mines.

Injection of coal combustion byproducts into the Omega Mine for the reduction of acid mine drainage

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gray, T.A.; Moran, T.C.; Broschart, D.W.

1998-12-31

The Omega Mine Complex is located outside of Morgantown, West Virginia. The mine is in the Upper Freeport Coal, an acid-producing coal seam. The coal was mined in a manner that has resulted in acid mine drainage (AMD) discharges at multiple points. During the 1990`s, the West Virginia Division of Environmental Protection (WVDEP) assumed responsibility for operating a collection and treatment system for the AMD. Collection and treatment costs are approximately $300,000 per year. An innovative procedure of injecting grout into the mine workings to reduce AMD and the resulting treatment costs is proposed. The procedure involves injecting grout mixesmore » composed primarily of coal combustion byproducts (CCB`s) and water, with a small quantity of cement. The intention of the injection program is to fill the mine voids in the north lobe of the Omega Mine (an area where most of the acidity is believed to be generated) with the grout, thus reducing the contact of air and water with potentially acidic material. The grout mix design consists of an approximate 1:1 ratio of fly ash to byproducts from fluidized bed combustion. Approximately 100 gallons of water per cubic yard of grout is used to help achieve flowability. Observation of the mine workings via subsurface borings and downhole video camera operation confirmed that first-mined areas were generally open while second-mined areas were generally partially collapsed. Closer injection hole spacing was used in second-mined areas to account for collapsed workings. The construction documents have been prepared with the project being bid in late 1997. The engineer`s cost estimate was approximately $2,500,000, with the low bid of approximately $2,300,000 being submitted by Howard Concrete Pumping of Bridgeville, PA.« less

Comments on Interior’s Surface Mining Regulations.

DTIC Science & Technology

1981-08-05

regulations and responses to pro- posed regulati n, (2) identified studies on cost/benefit analy- sis of environme ital regulations and selected ...agricultural production at the national level, in some rural counties essentially the entire area is underlain with strippable coal. obviously, surface mining...1980).) Illinois, which has the most strippable coal reserves underlying prime farmland, has two heavily worked coal seams which are continuous. One

Cutting sound enhancement system for mining machines

DOEpatents

Leigh, Michael C.; Kwitowski, August J.

1992-01-01

A cutting sound enhancement system (10) for transmitting an audible signal from the cutting head (101) of a piece of mine machinery (100) to an operator at a remote station (200), wherein, the operator using a headphone unit (14) can monitor the difference in sounds being made solely by the cutting head (101) to determine the location of the roof, floor, and walls of a coal seam (50).

Testing Seam Concepts for Advanced Multilayer Insulation

NASA Technical Reports Server (NTRS)

Chato, D. J.; Johnson, W. L.; Alberts, Samantha J.

2017-01-01

Multilayer insulation (MLI) is considered the state of the art insulation for cryogenic propellant tanks in the space environment. MLI traditionally consists of multiple layers of metalized films separated by low conductivity spacers. In order to better understand some of the details within MLI design and construction, GRC has been investigating the heat loads caused by multiple types of seams. To date testing has been completed with 20 layer and 50 layer blankets. Although a truly seamless blanket is not practical, a blanket lay-up where each individual layer was overlapped and tapped together was used as a baseline for the other seams tests. Other seams concepts tested included: an overlap where the complete blanket was overlapped on top of itself; a butt joint were the blankets were just trimmed and butted up against each other, and a staggered butt joint where the seam in the out layers is offset from the seam in the inner layers. Measured performance is based on a preliminary analysis of rod calibration tests conducted prior to the start of seams testing. Baseline performance for the 50 layer blanket showed a measured heat load of 0.46 Watts with a degradation to about 0.47 Watts in the seamed blankets. Baseline performance for the 20 layer blanket showed a measured heat load of 0.57 Watts. Heat loads for the seamed tests are still begin analyzed. So far analysis work has suggested the need for corrections due to heat loads from both the heater leads and the instrumentation wires. A careful re-examination of the calibration test results with these factors accounted for is also underway. This presentation will discuss the theory of seams in MLI, our test results to date, and the uncertainties in our measurements.

Process for hydraulically mining coal. [28 claims

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shoji, K.; Sieling, R.E.; Taylor, J.T.

The invention is a method for the hydraulic mining of coal of varying hardness. It is described in particular as to coal of the type occurring in the Balmer seam in British Columbia. By the method at least two parallel spaced entries are driven upward through a seam of coal. Monitors are positioned in each entry. Each monitor is horizontally and vertically pivotable, and has nozzle means from which a jet of water under a pressure of about 1900 to 2200 psi is emitted. The high pressure jet cuts the coal, which is then fed to a machine that breaksmore » and crushes the coal into sizes wherein the resultant coal/water slurry will flow down a sloped flume into a dewatering station. The method further embodies differentially retreating along adjacent parallel entries by increments of desirably at least about 40 feet each. By the different retreat system, as a panel of coal is hydraulically mined in one entry, the monitor and associated equipment in a second adjacent parallel entry are moved back the desired increment to the next working position (retreated). When the panel of coal in the first entry is mined, the monitor is retreated in the same manner and hydraulic mining commences in the second adjacent parallel entry. The operation is thus alternated along the length of the parallel entries. 28 claims, 4 figures.« less

Geochemistry of trace elements in coals from the Zhuji Mine, Huainan Coalfield, Anhui, China

USGS Publications Warehouse

Sun, R.; Liu, Gaisheng; Zheng, Lingyun; Chou, C.-L.

2010-01-01

The abundances of nine major elements and thirty-eight trace elements in 520 samples of low sulfur coals from the Zhuji Mine, Huainan Coalfield, Anhui, China, were determined. Samples were mainly collected from 10 minable coal seams of 29 boreholes during exploration. The B content in coals shows that the influence of brackish water decreased toward the top of coal seams; marine transgression and regression occurred frequently in the Lower Shihezi Formation. A wide range of elemental abundances is found. Weighted means of Na, K, Fe, P, Be, B, Co, Ni, Cr, Se, Sb, Ba, and Bi abundances in Zhuji coals are higher, and the remainder elements are either lower or equal to the average values of elements in coals of northern China. Compared to the Chinese coals, the Zhuji coals are higher in Na, K, Be, B, Cr, Co, Se, Sn, Sb, and Bi, but lower in Ti, P, Li, V and Zn. The Zhuji coals are lower only in S, P, V and Zn than average U.S. and world coals. Potassium, Mg, Ca, Mn, Sr, As, Se, Sb and light rare earth elements (LREE) had a tendency to be enriched in thicker coal seams, whereas Fe, Ti, P, V, Co, Ni, Y, Mo, Pb and heavy rare earth elements (HREE) were inclined to concentrate in thinner coal seams. The enrichment of some elements in the Shanxi or Upper Shihezi Formations is related to their depositional environments. The elements are classified into three groups based on their stratigraphic distributions from coal seams 3 to 11-2, and the characteristics of each group are discussed. Lateral distributions of selected elements are also investigated. The correlation coefficients of elemental abundances with ash content show that the elements may be classified into four groups related to modes of occurrence of these elements. ?? 2009 Elsevier B.V. All rights reserved.

A synoptic description of coal basins via image processing

NASA Technical Reports Server (NTRS)

Farrell, K. W., Jr.; Wherry, D. B.

1978-01-01

An existing image processing system is adapted to describe the geologic attributes of a regional coal basin. This scheme handles a map as if it were a matrix, in contrast to more conventional approaches which represent map information in terms of linked polygons. The utility of the image processing approach is demonstrated by a multiattribute analysis of the Herrin No. 6 coal seam in Illinois. Findings include the location of a resource and estimation of tonnage corresponding to constraints on seam thickness, overburden, and Btu value, which are illustrative of the need for new mining technology.

Kinetics of bed fracturing around mine workings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Veksler, Yu.A.

1988-03-01

A failure of the bed near the walls of the workings of a mine away from the face occurs gradually over time and in this paper the authors take a kinetic approach to evaluating its development. The influence of certain mine engineering factors on the pattern of bed fracturing is discussed. The effect of the depth of mining is shown. Cracking occurs in the portion of the seam at the face near the ground at some distance from it on the interface between soft and hard coal. The density of the fractured rocks and their response affect the bed fracturingmore » near the stope face.« less

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

NASA Astrophysics Data System (ADS)

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.

Research on preventive technologies for bed-separation water hazard in China coal mines

NASA Astrophysics Data System (ADS)

Gui, Herong; Tong, Shijie; Qiu, Weizhong; Lin, Manli

2018-03-01

Bed-separation water is one of the major water hazards in coal mines. Targeted researches on the preventive technologies are of paramount importance to safe mining. This article studied the restrictive effect of geological and mining factors, such as lithological properties of roof strata, coal seam inclination, water source to bed separations, roof management method, dimensions of mining working face, and mining progress, on the formation of bed-separation water hazard. The key techniques to prevent bed-separation water-related accidents include interception, diversion, destructing the buffer layer, grouting and backfilling, etc. The operation and efficiency of each technique are corroborated in field engineering cases. The results of this study will offer reference to countries with similar mining conditions in the researches on bed-separation water burst and hazard control in coal mines.

Coal Seam Methane Pressure as a Parameter Determining the Level of the Outburst Risk - Laboratory and in Situ Research / Ciśnienie Złożowe Jako Parametr Określający Stan Zagrożenia Wyrzutami Metanu I Skał - Badania Laboratoryjne I Kopalniane

NASA Astrophysics Data System (ADS)

Skoczylas, Norbert

2012-12-01

Scarcity of research focusing on the evaluation of the coal seam methane pressure as a parameter determining the outburst risk makes it difficult to assess the value for which the level of this risk increases considerably. It is obvious that, apart from the gas factor, the evaluation of the threat should also take into account the strength factor. The research presented in this paper attempted at estimating the level of the outburst risk on the basis of the coal seam methane pressure value and firmness of coal. In this work, the author seeks to present both the relevant laboratory research and the measurements carried out in mines.

Law of Strata Pressure Behavior in Shallow Coal Seam

NASA Astrophysics Data System (ADS)

Zhao, Jian; Liu, Leibin; Zheng, Zhiyang

2018-02-01

The law of strata pressure behavior in shallow coal seam is analyzed, according to the load data of Jinjie Coal Mine 31109 working face hydraulic supports. The first weighting distance of main roof is 80 m, and the periodic weighting distance of main roof is about 20 m. And according to the load data in the middle and both ends of the working face, the working resistance of hydraulic supports and the setting load are a bit small, so they couldn’t meet the needs of supporting roof. Then, the front abutment pressure of working face is analyzed by numerical simulation. It does not only explain the reason that the load is too big, but also explains the reason that the strata pressure behavior in shallow coal seam is serious. The length of undamaged main roof rock beam verifies the correctness of the periodic weighting distance.

Stress distribution characteristics in the vicinity of coal seam floor

NASA Astrophysics Data System (ADS)

Cui, Zimo; Chanda, Emmanuel; Zhao, Jingli; Wang, Zhihe

2018-01-01

Although longwall top-coal caving (LTCC) has been a popular, more productive and cost-effective method in recent years, roadway floor heave and rock bursts frequently appear when exploiting such coal seams with large dip angle. This paper proposes addressing this problem by adopting three-dimensional roadway layout of stagger arrangement (3-D RLSA). In this study, the first step was to analyse the stress distribution characteristics in the vicinity of coal seam floor based on the stress slip line field theory. In the second step, numerical calculation using FLAC3D was conducted. Finally, an evaluation of the 3-D RLSA for solving this particular issue was given. Results indicate that for this particular mine the proposed 3-D RLSA results in 24% increase in the coal recovery ratio and a modest reduction in excavation and maintenance costs compared to the conventional LTCC method.

Non-destructive testing principles and accurate evaluation of the hydraulic measure impact range using the DC method

NASA Astrophysics Data System (ADS)

Qiu, Liming; Shen, Rongxi; Song, Dazhao; Wang, Enyuan; Liu, Zhentang; Niu, Yue; Jia, Haishan; Xia, Shankui; Zheng, Xiangxin

2017-12-01

An accurate and non-destructive evaluation method for the hydraulic measure impact range in coal seams is urgently needed. Aiming at the application demands, a theoretical study and field test are presented using the direct current (DC) method to evaluate the impact range of coal seam hydraulic measures. We firstly analyzed the law of the apparent resistivity response of an abnormal conductive zone in a coal seam, and then investigated the principle of non-destructive testing of the coal seam hydraulic measure impact range using the DC method, and used an accurate evaluation method based on the apparent resistivity cloud chart. Finally, taking hydraulic fracturing and hydraulic flushing as examples, field experiments were carried out in coal mines to evaluate the impact ranges. The results showed that: (1) in the process of hydraulic fracturing, coal conductivity was enhanced by high-pressure water in the coal seam, and after hydraulic fracturing, the boundary of the apparent resistivity decrease area was the boundary impact range. (2) In the process of hydraulic flushing, coal conductivity was reduced by holes and cracks in the coal seam, and after hydraulic flushing, the boundary of the apparent resistivity increase area was the boundary impact range. (3) After the implementation of the hydraulic measures, there may be some blind zones in the coal seam; in hydraulic fracturing blind zones, the apparent resistivity increased or stayed constant, while in hydraulic flushing blind zones, the apparent resistivity decreased or stayed constant. The DC method realized a comprehensive and non-destructive evaluation of the impact range of the hydraulic measures, and greatly reduced the time and cost of evaluation.

A risk assessment for exposure to grunerite asbestos (amosite) in an iron ore mine

PubMed Central

Nolan, R. P.; Langer, A. M.; Wilson, Richard

1999-01-01

The potential for health risks to humans exposed to the asbestos minerals continues to be a public health concern. Although the production and use of the commercial amphibole asbestos minerals—grunerite (amosite) and riebeckite (crocidolite)—have been almost completely eliminated from world commerce, special opportunities for potentially significant exposures remain. Commercially viable deposits of grunerite asbestos are very rare, but it can occur as a gangue mineral in a limited part of a mine otherwise thought asbestos-free. This report describes such a situation, in which a very localized seam of grunerite asbestos was identified in an iron ore mine. The geological occurrence of the seam in the ore body is described, as well as the mineralogical character of the grunerite asbestos. The most relevant epidemiological studies of workers exposed to grunerite asbestos are used to gauge the hazards associated with the inhalation of this fibrous mineral. Both analytical transmission electron microscopy and phase-contrast optical microscopy were used to quantify the fibers present in the air during mining in the area with outcroppings of grunerite asbestos. Analytical transmission electron microscopy and continuous-scan x-ray diffraction were used to determine the type of asbestos fiber present. Knowing the level of the miner’s exposures, we carried out a risk assessment by using a model developed for the Environmental Protection Agency. PMID:10097051

Study on the change law of soil in subsidence area of horizontal coal seam

NASA Astrophysics Data System (ADS)

Li, Pengfeng; Wang, Shugang; Liu, Wei

2017-11-01

In order to provide theoretical basis for land reclamation in subsidence area, the mining subsidence area is divided into three areas: zone I (stretching zone), zone II (compression zone) and zone III (neutral zone). On this basis, the change characteristics of the soil in the three areas of the horizontal coal seam mining subsidence area are studied. The results show that: due to stretching, soil of zone I cracks was developed, the soil continuity damage, poor integrity, serious leakage of soil Water Leakage fertilizer, the area shows the soil water holding capacity decreased, the decline of soil fertility, soil coarsening and barren trend. The soil mass in zone II is compressed and the soil structure is relatively complete, but the soil bulk density increases correspondingly, while the soil porosity decreases gradually and the permeability decreases. The main soil layer in the zone III is vertical deformation, and the soil integrity is better. But the influence of mined out area leads to the movement of water and nutrients to the lower part of the soil. This paper suggests that in the land reclamation process should adopt corresponding reclamation method based on the variation law of the three soil area of reclamation area of mining subsidence, for improving soil physicochemical properties, so as to achieve the purpose of effective reclamation.

Potential Energy Sources Pose Mining Problem

ERIC Educational Resources Information Center

Chemical and Engineering News, 1974

1974-01-01

Summarizes the discussions of a Division of Industrial and Engineering Chemistry symposium on solids handling for synthetic fuels production. Included is a description of technical difficulties with the use of coal seams and deposits of oil shale and oil sand as potential sources of fuel. (CC)

Geophysical examination of coal deposits

NASA Astrophysics Data System (ADS)

Jackson, L. J.

1981-04-01

Geophysical techniques for the solution of mining problems and as an aid to mine planning are reviewed. Techniques of geophysical borehole logging are discussed. The responses of the coal seams to logging tools are easily recognized on the logging records. Cores for laboratory analysis are cut from selected sections of the borehole. In addition, information about the density and chemical composition of the coal may be obtained. Surface seismic reflection surveys using two dimensional arrays of seismic sources and detectors detect faults with throws as small as 3 m depths of 800 m. In geologically disturbed areas, good results have been obtained from three dimensional surveys. Smaller faults as far as 500 m in advance of the working face may be detected using in seam seismic surveying conducted from a roadway or working face. Small disturbances are detected by pulse radar and continuous wave electromagnetic methods either from within boreholes or from underground. Other geophysical techniques which explicit the electrical, magnetic, gravitational, and geothermal properties of rocks are described.

Environmental impact of coal mining and coal seam gas production on surface water quality in the Sydney basin, Australia.

PubMed

Ali, A; Strezov, V; Davies, P; Wright, I

2017-08-01

The extraction of coal and coal seam gas (CSG) will generate produced water that, if not adequately treated, will pollute surface and groundwater systems. In Australia, the discharge of produced water from coal mining and related activities is regulated by the state environment agency through a pollution licence. This licence sets the discharge limits for a range of analytes to protect the environment into which the produced water is discharged. This study reports on the impact of produced water from coal mine activities located within or discharging into high conservation environments, such as National Parks, in the outer region of Sydney, Australia. The water samples upstream and downstream from the discharge points from six mines were taken, and 110 parameters were tested. The results were assessed against a water quality index (WQI) which accounts for pH, turbidity, dissolved oxygen, biochemical oxygen demand, total dissolved solids, total phosphorus, nitrate nitrogen and E .coli. The water quality assessment based on the trace metal contents against various national maximum admissible concentration (MAC) and their corresponding environmental impacts was also included in the study which also established a base value of water quality for further study. The study revealed that impacted water downstream of the mine discharge points contained higher metal content than the upstream reference locations. In many cases, the downstream water was above the Australia and New Zealand Environment Conservation Council and international water quality guidelines for freshwater stream. The major outliers to the guidelines were aluminium (Al), iron (Fe), manganese (Mn), nickel (Ni) and zinc (Zn). The WQI of surface water at and downstream of the discharge point was lower when compared to upstream or reference conditions in the majority of cases. Toxicology indices of metals present in industrial discharges were used as an additional tool to assess water quality, and the newly proposed environmental water quality index (EWQI) lead to better trend in the impact of coal and coal seam gas mining activities on surface water quality when compared to the upstream reference water samples. Metal content limits were based on the impact points assigned by the Agency for Toxic Substances and Disease Registry, USA. For environmental and health impact assessment, the approach used in this study can be applied as a model to provide a basis to assess the anthropogenic contribution from the industrial and mining activities on the environment.

Fast and safe gas detection from underground coal fire by drone fly over.

PubMed

Dunnington, Lucila; Nakagawa, Masami

2017-10-01

Underground coal fires start naturally or as a result of human activities. Besides burning away the important non-renewable energy resource and causing financial losses, burning coal seams emit carbon dioxide, carbon monoxide, sulfur oxide and methane, and is a leading cause of smog, acid rain, global warming, and air toxins. In the U.S. alone, the combined cost of coal-fire remediation projects that have been completed, budgeted, or projected by the U.S. Department of the Interior's Office of Surface Mining Remediation and Enforcement (OSM), exceeds $1 billion. It is estimated that these fires generate as much as 3% of the world's annual carbon dioxide emissions and consume as much as 5% of its minable coal. Considering the magnitude of environmental impact and economic loss caused by burning underground coal seams, we have developed a new, safe, reliable surface measurement of coal fire gases to assess the nature of underground coal fires. We use a drone mounted with gas sensors. Drone collected gas concentration data provides a safe alternative for evaluating the rank of a burning coal seam. In this study, a new method of determining coal rank by gas ratios is developed. Coal rank is valuable for defining parameters of a coal seam such as burn temperature, burn rate, and volume of burning seam. Copyright © 2017 Elsevier Ltd. All rights reserved.

Coal workers' pneumoconiosis in the United States: regional differences 40 years after implementation of the 1969 Federal Coal Mine Health and Safety Act.

PubMed

Suarthana, Eva; Laney, A Scott; Storey, Eileen; Hale, Janet M; Attfield, Michael D

2011-12-01

To assess whether the recent increases in the prevalence of coal workers' pneumoconiosis (CWP) in the USA reflect increased measured exposures over recent decades, and to identify other potential causative factors. The observed CWP prevalence was calculated for 12,408 underground coal miner participants in the Coal Workers' Health Surveillance Program for the period 2005-2009, stratified by the Mine Safety and Health Administration (MSHA) geographical districts. The predicted prevalence was estimated using a published exposure-response model from a large epidemiological study among U.S. coal miners using dust exposure, tenure, miner's age and coal rank as predictors. χ2 Testing was performed to compare the observed versus predicted CWP prevalence. Observed prevalence was significantly higher than predicted prevalence in MSHA districts 4-7 (central Appalachian region) (10.1% vs. 4.2%; prevalence ratio (PR) 2.4; p<0.001) and significantly lower than predicted in other regions (1.6% vs. 3.6%; PR 0.4; p<0.001). The central Appalachian region had a significantly older workforce with greater mining tenure, a lower proportion of mines with 200 or more employees, and lower seam heights. Significant lower average compliance dust concentrations were reported for this region. The observed CWP prevalence substantially exceeded predicted levels in central Appalachia. However, the increased prevalence was not explained by the measured levels of dust exposures. Likely contributing factors include mine size and low seam mining, which may be associated with higher exposure to silica. Further study is needed to characterise the responsible factors for the elevated CWP rates in central Appalachia.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Williams, G.

About 40 miles outside of Price, UT, is Natomas Trail Mountain Coal Co. Owned and operated by Natomas Coal, Englewood, CO, Trail Mountain Coal is a two section mine using continuous miners, shuttle cars and belt haulage. Seam height averages about seven feet. Until about a year and a half ago, Trail Mountain Coal Co. was not much different from most mines. With about 120 employees, they were faced with the same problems seen throughout the industry such as high absenteeism, inexperience, poor communication and cooperation, and a host of other problems.

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

NASA Astrophysics Data System (ADS)

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.

Analysis of gob gas venthole production performances for strata gas control in longwall mining.

PubMed

Karacan, C Özgen

2015-10-01

Longwall mining of coal seams affects a large area of overburden by deforming it and creating stress-relief fractures, as well as bedding plane separations, as the mining face progresses. Stress-relief fractures and bedding plane separations are recognized as major pathways for gas migration from gas-bearing strata into sealed and active areas of the mines. In order for strata gas not to enter and inundate the ventilation system of a mine, gob gas ventholes (GGVs) can be used as a methane control measure. The aim of this paper is to analyze production performances of GGVs drilled over a longwall panel. These boreholes were drilled to control methane emissions from the Pratt group of coals due to stress-relief fracturing and bedding plane separations into a longwall mine operating in the Mary Lee/Blue Creek coal seam of the Upper Pottsville Formation in the Black Warrior Basin, Alabama. During the course of the study, Pratt coal's reservoir properties were integrated with production data of the GGVs. These data were analyzed by using material balance techniques to estimate radius of influence of GGVs, gas-in-place and coal pressures, as well as their variations during mining. The results show that the GGVs drilled to extract gas from the stress-relief zone of the Pratt coal interval is highly effective in removing gas from the Upper Pottsville Formation. The radii of influence of the GGVs were in the order of 330-380 m, exceeding the widths of the panels, due to bedding plane separations and stress relieved by fracturing. Material balance analyses indicated that the initial pressure of the Pratt coals, which was around 648 KPa when longwall mining started, decreased to approximately 150 KPa as the result of strata fracturing and production of released gas. Approximately 70% of the initial gas-in-place within the area of influence of the GGVs was captured during a period of one year.

Block coals from Indiana: Inferences on changing depositional environment

USGS Publications Warehouse

Mastalerz, Maria; Padgett, P.L.; Eble, C.F.

2000-01-01

Significant differences in coal petrography, palynology and coal quality were found between the Lower Block and Upper Block Coal Members (Brazil Formation, Pennsylvanian) in Daviess County, Indiana. The Lower Block Coal Member ranges in thickness from 51 to 74 cm and the Upper Block Coal Member ranges from 20 to 65 cm. Average sulfur content and ash yield of the Lower Block coal (0.98%, 7.65%) are lower than in the Upper Block coal. Megascopically, the coals show distinct differences. The Lower Block is a banded coal with numerous thin fusain horizons and a thin clay parting in the lower third of the seam. The Upper Block coal has a dulling-upward trend, with a bright clarain found at the base that grades into a clarain and then into a durain in the upper portion of the seam. Vitrinite content of the Lower Block coal ranges from 63% to 78%, with the highest vitrinite content found in the middle portion of the seam. In the Upper Block coal, vitrinite content ranges from 40% to 83%, with the highest values found in the lower part of the seam. Ash yield is higher in the upper part of the Upper Block coal, reaching up to 40%. The Lower Block coal is dominated by lycopod trees and tree ferns. The Upper Block coal shows marked differences in spore assemblages between lower and upper parts of the seam. The lower half is dominated by large lycopod trees and tree ferns, similar to the Lower Block coal. The upper half is dominated by small lycopods, mainly Densosporites and Radiizonates. These differences between the Lower Block and Upper Block Coal Members are significant correlation tools applicable to mining exploration and chronostratigraphy. (C) 2000 Elsevier Science B.V. All rights reserved.Significant differences in coal petrography, palynology and coal quality were found between the Lower Block and Upper Block Coal Members (Brazil Formation, Pennsylvanian) in Daviess County, Indiana. The Lower Block Coal Member ranges in thickness from 51 to 74 cm and the Upper Block Coal Member ranges from 20 to 65 cm. Average sulfur content and ash yield of the Lower Block coal (0.98%, 7.65%) are lower than in the Upper Block coal. Megascopically, the coals show distinct differences. The Lower Block is a banded coal with numerous thin fusain horizons and a thin clay parting in the lower third of the seam. The Upper Block coal has a dulling-upward trend, with a bright clarain found at the base that grades into a clarain and then into a durain in the upper portion of the seam. Vitrinite content of the Lower Block coal ranges from 63% to 78%, with the highest vitrinite content found in the middle portion of the seam. In the Upper Block coal, vitrinite content ranges from 40% to 83%, with the highest values found in the lower part of the seam. Ash yield is higher in the upper part of the Upper Block coal, reaching up to 40%. The Lower Block coal is dominated by lycopod trees and tree ferns. The Upper Block coal shows marked differences in spore assemblages between lower and upper parts of the seam. The lower half is dominated by large lycopod trees and tree ferns, similar to the Lower Block coal. The upper half is dominated by small lycopods, mainly Densosporites and Radiizonates. These differences between the Lower Block and Upper Block Coal members are significant correlation tools applicable to mining exploration and chronostratigraphy.

30 CFR 75.381 - Escapeways; anthracite mines.

Code of Federal Regulations, 2011 CFR

2011-07-01

... similar facilities where the escapeways cross over obstructions; and (4) Maintained at least 4 feet wide by 5 feet high. If the pitch or thickness of the coal seam does not permit these dimensions to be maintained other dimensions may be approved in the ventilation plan. (5) Provided with a continuous, durable...

Occurrence and morphology of carbonate concretions in the Beulah-Zap coal bed, Williston basin, North Dakota

USGS Publications Warehouse

Keighin, C.W.M.; Flores, R.M.; Rowland, T.

1996-01-01

Carbonate concretionary bodies were encountered during mining of the Beulah-Zap lignite seam in the Coteau Properties' Freedom mine, Mercer County, North Dakota. Preliminary studies show that areal and vertical distribution of the concretions are variable. All concretions examined are composed almost entirely of calcite. They occur as thin tabular bodies, as more or less elliptical forms, or as tear shaped bodies, and may occur individually or as clusters of buff-colored, poorly consolidated to solidly crystalline material. The carbonate masses vary in size from a few millimeters to tens of centimeters. Bedding in the lignite may display some compactional folding over dense spheroidal to elliptical concretions, indicating formation of the concretions prior to compaction. Internal morphology of the concretions is complex, and includes cone-in-cone structure, cross-cutting calcite veinlets, and multiple generations of calcite. Carbon isotope values suggest the concretions are composed of biogenic carbonate, probably related to early diagenesis and decomposition of organic matter (peat); oxygen isotope values are light, and consistent with a freshwater origin.

Thermodynamic Changes in the Coal Matrix - Gas - Moisture System Under Pressure Release and Phase Transformations of Gas Hydrates

NASA Astrophysics Data System (ADS)

Dyrdin, V. V.; Smirnov, V. G.; Kim, T. L.; Manakov, A. Yu.; Fofanov, A. A.; Kartopolova, I. S.

2017-06-01

The physical processes occurring in the coal - natural gas system under the gas pressure release were studied experimentally. The possibility of gas hydrates presence in the inner space of natural coal was shown, which decomposition leads to an increase in the amount of gas passing into the free state. The decomposition of gas hydrates can be caused either by the seam temperature increase or the pressure decrease to lower than the gas hydrates equilibrium curve. The contribution of methane released during gas hydrates decomposition should be taken into account in the design of safe mining technologies for coal seams prone to gas dynamic phenomena.

Exploring the determinants of health and wellbeing in communities living in proximity to coal seam gas developments in regional Queensland.

PubMed

Mactaggart, Fiona; McDermott, Liane; Tynan, Anna; Gericke, Christian A

2017-08-03

There is some concern that coal seam gas mining may affect health and wellbeing through changes in social determinants such as living and working conditions, local economy and the environment. The onward impact of these conditions on health and wellbeing is often not monitored to the same degree as direct environmental health impacts in the mining context, but merits attention. This study reports on the findings from a recurrent theme that emerged from analysis of the qualitative component of a comprehensive Health Needs Assessment (HNA) conducted in regional Queensland: that health and wellbeing of communities was reportedly affected by nearby coal seam gas (CSG) development beyond direct environmental impacts. Qualitative analysis was initially completed using the Framework Method to explore key themes from 11 focus group discussions, 19 in-depth interviews, and 45 key informant interviews with health and wellbeing service providers and community members. A key theme emerged from the analysis that forms the basis of this paper. This study is part of a larger comprehensive HNA involving qualitative and quantitative data collection to explore the health and wellbeing needs of three communities living in proximity to CSG development in regional Queensland, Australia. Communities faced social, economic and environmental impacts from the rapid growth of CSG development, which were perceived to have direct and indirect effects on individual lifestyle factors such as alcohol and drug abuse, family relationships, social capital and mental health; and community-level factors including social connectedness, civic engagement and trust. Outer regional communities discussed the effects of mining activity on the fabric of their town and community, whereas the inner regional community that had a longer history of industrial activity discussed the impacts on families and individual health and wellbeing. The findings from this study may inform future health service planning in regions affected by CSG in the development /construction phase and provide the mining sector in regional areas with evidence from which to develop social responsibility programs that encompass health, social, economic and environmental assessments that more accurately reflect the needs of the affected communities.

In Brief: Coal mining regulations

NASA Astrophysics Data System (ADS)

Showstack, Randy

2009-12-01

The U.S. Department of the Interior (DOI) announced on 18 November measures to strengthen the oversight of state surface coal mining programs and to promulgate federal regulations to protect streams affected by surface coal mining operations. DOI's Office of Surface Mining Reclamation and Enforcement (OSM) is publishing an advance notice of a proposed rule about protecting streams from adverse impacts of surface coal mining operations. A rule issued by the Bush administration in December 2008 allows coal mine operators to place excess excavated materials into streams if they can show it is not reasonably possible to avoid doing so. “We are moving as quickly as possible under the law to gather public input for a new rule, based on sound science, that will govern how companies handle fill removed from mountaintop coal seams,” according to Wilma Lewis, assistant secretary for Land and Minerals Management at DOI.

USA's Black Thunder mine: a truck and shovel operation

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dorling, I.

During 1966/1967, ARCO obtained over 2,631 hectares (6,500 acres) of federal and state coal leases, and initial exploration was started. A total of 312 coal core holes were drilled and logged to determine the reserves and quality of the coal. The results indicated that a large surface mine could be developed to exploit the substantial reserves. The application procedure for permits was started early in 1974. Thunder Basin Coal Company is mining the Wyodak-Anderson Seam where the coal is about 21 meters (69 feet) thick. It has been estimated that a total of 750,000,000 tons of coal exist with amore » 0.3 to 0.4 percent sulfur content and a heating value of about 8,600 Btu per pound. The seam is mined in one lift using electric shovels and trucks. There are many factors which govern the choice of either a dragline or a truck and shovel operation for removing overburden. At the Black Thunder mine the conditions which favored the choice of the truck and shovel method were topography and pit geometry. The run-of-mine coal is dumped into two 540-ton hoppers. Underground vibrating grizzly feeders (2,500 tph capacity) pass the coal into 2,500 tph primary single-roll crushers, where the ROM coal is reduced to minus 8 inches. A 72-inch-wide elevating conveyor carries the coal to a 110-ton surge hopper, and is then fed into two secondary crushers where the coal is further reduced to minus-2 inches. The system is able to handle 5,000 tons of ROM coal per hour. The total production of coal from the mine in 1978 is expected to be about 3,000,000 tons, depending on customer requirements. It is expected that in 1979 the output will rise to 8,000,000 tons, and by 1983 the full planned production of 20,000,000 tons a year will be reached. (LTN)« less

Seamless image stitching by homography refinement and structure deformation using optimal seam pair detection

NASA Astrophysics Data System (ADS)

Lee, Daeho; Lee, Seohyung

2017-11-01

We propose an image stitching method that can remove ghost effects and realign the structure misalignments that occur in common image stitching methods. To reduce the artifacts caused by different parallaxes, an optimal seam pair is selected by comparing the cross correlations from multiple seams detected by variable cost weights. Along the optimal seam pair, a histogram of oriented gradients is calculated, and feature points for matching are detected. The homography is refined using the matching points, and the remaining misalignment is eliminated using the propagation of deformation vectors calculated from matching points. In multiband blending, the overlapping regions are determined from a distance between the matching points to remove overlapping artifacts. The experimental results show that the proposed method more robustly eliminates misalignments and overlapping artifacts than the existing method that uses single seam detection and gradient features.

30 CFR 773.6 - Public participation in permit processing.

Code of Federal Regulations, 2010 CFR

2010-07-01

...) Information that pertains only to the analysis of the chemical and physical properties of the coal to be mined... operation, including the U.S. Department of Agriculture Soil Conservation Service district office, the local... pertaining to coal seams, test borings, core samplings, or soil samples in an application shall be made...

30 CFR 773.6 - Public participation in permit processing.

Code of Federal Regulations, 2011 CFR

2011-07-01

...) Information that pertains only to the analysis of the chemical and physical properties of the coal to be mined... operation, including the U.S. Department of Agriculture Soil Conservation Service district office, the local... pertaining to coal seams, test borings, core samplings, or soil samples in an application shall be made...

Permeability Prediction in Deep Coal Seam: A Case Study on the No. 3 Coal Seam of the Southern Qinshui Basin in China

PubMed Central

2013-01-01

The coal permeability is an important parameter in mine methane control and coal bed methane (CBM) exploitation, which determines the practicability of methane extraction. Permeability prediction in deep coal seam plays a significant role in evaluating the practicability of CBM exploitation. The coal permeability depends on the coal fractures controlled by strata stress, gas pressure, and strata temperature which change with depth. The effect of the strata stress, gas pressure, and strata temperature on the coal (the coal matrix and fracture) under triaxial stress and strain conditions was studied. Then we got the change of coal porosity with strata stress, gas pressure, and strata temperature and established a coal permeability model under tri-axial stress and strain conditions. The permeability of the No. 3 coal seam of the Southern Qinshui Basin in China was predicted, which is consistent with that tested in the field. The effect of the sorption swelling on porosity (permeability) firstly increases rapidly and then slowly with the increase of depth. However, the effect of thermal expansion and effective stress compression on porosity (permeability) increases linearly with the increase of depth. The most effective way to improve the permeability in exploiting CBM or extracting methane is to reduce the effective stress. PMID:24396293

Spatio-temporal evolution of apparent resistivity during coal-seam hydraulic flushing

NASA Astrophysics Data System (ADS)

Li, Dexing; Wang, Enyuan; Song, Dazhao; Qiu, Liming; Kong, Xiangguo

2018-06-01

Hydraulic flushing in gas predrainage is widely used, but the hydraulic-flushing effect is evaluated in a traditional way, by determining the desorption volume, moisture content, gas drainage rate and other conventional indices. To verify the rationality and feasibility of the multielectrode resistivity method in the evaluation of coal-seam hydraulic flushing and to research the spatio-temporal evolution of apparent resistivity during hydraulic flushing, a field test was conducted in 17# coal seam at Nuodong Mine, Guizhou. During hydraulic flushing, four stages were defined according to the variation in coal rock resistivity with time, namely, the preparation stage, the sharply decreasing stage, the rapidly increasing stage and the steady stage. The apparent resistivity of the coal rock mass is affected mainly by its own degree of fragmentation and flushing volume. A more serious rupture and a greater flushing volume yield a smaller apparent resistivity during the sharply decreasing stage and a higher resistivity during the stable stage. After three months of gas predrainage, the residual gas content and the gas pressure at different points in the expected affected area decrease below the critical value. Changes in the residual gas content and gas pressure at these points are consistent with the apparent resistivity, which validates the rationality and feasibility of the multielectrode resistivity method in evaluating coal-seam hydraulic flushing.

Total number of longwall faces drops below 50

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fiscor, S.

2009-02-15

For the first time since Coal Age began its annual Longwall Census the number of faces has dropped below 50. A total of five mines operate two longwall faces. CONSOL Energy remains the leader with 12 faces. Arch Coal operates five longwall mines; Robert E. Murray owns five longwall mines. West Virginia has 13 longwalls, followed by Pennsylvania (8), Utah (6) and Alabama (6). A detailed table gives for each longwall installation, the ownership, seam height, cutting height, panel width and length, overburden, number of gate entries, depth of cut, model of equipment used (shearer, haulage system, roof support, facemore » conveyor, stage loader, crusher, electrical controls and voltage to face). 2 tabs., 1 photo.« less

Triggering effect of mining at different horizons in the rock mass with excavations. Mathematical modeling

NASA Astrophysics Data System (ADS)

Eremin, M. O.; Makarov, P. V.

2017-12-01

On the basis of a quite simple structural model of rock mass, containing coal seams on two horizons, coal mining is numerically modeled. A finite difference numerical technique is applied. At first, mining starts at the upper horizon and then moves to the lower horizon. It is shown that a mining process at the lower horizon has a significant triggering influence on the growth of damage zones in the roof and floor at the upper horizon. The features of spatiotemporal migration of deformation activity are studied numerically. Foci of large-scale fracture are located at the boundary of the seismic silence zone and the zone where the deformation activity migrates. This boundary has an additional characteristic: the maximum gradient of rock pressure is observed in this zone.

Stochastic reservoir simulation for the modeling of uncertainty in coal seam degasification

PubMed Central

Karacan, C. Özgen; Olea, Ricardo A.

2018-01-01

Coal seam degasification improves coal mine safety by reducing the gas content of coal seams and also by generating added value as an energy source. Coal seam reservoir simulation is one of the most effective ways to help with these two main objectives. As in all modeling and simulation studies, how the reservoir is defined and whether observed productions can be predicted are important considerations. Using geostatistical realizations as spatial maps of different coal reservoir properties is a more realistic approach than assuming uniform properties across the field. In fact, this approach can help with simultaneous history matching of multiple wellbores to enhance the confidence in spatial models of different coal properties that are pertinent to degasification. The problem that still remains is the uncertainty in geostatistical simulations originating from the partial sampling of the seam that does not properly reflect the stochastic nature of coal property realizations. Stochastic simulations and using individual realizations, rather than E-type, make evaluation of uncertainty possible. This work is an advancement over Karacan et al. (2014) in the sense of assessing uncertainty that stems from geostatistical maps. In this work, we batched 100 individual realizations of 10 coal properties that were randomly generated to create 100 bundles and used them in 100 separate coal seam reservoir simulations for simultaneous history matching. We then evaluated the history matching errors for each bundle and defined the single set of realizations that would minimize the error for all wells. We further compared the errors with those of E-type and the average realization of the best matches. Unlike in Karacan et al. (2014), which used E-type maps and average of quantile maps, using these 100 bundles created 100 different history match results from separate simulations, and distributions of results for in-place gas quantity, for example, from which uncertainty in coal property realizations could be evaluated. The study helped to determine the realization bundle that consisted of the spatial maps of coal properties, which resulted in minimum error. In addition, it was shown that both E-type and the average of realizations that gave the best match for invidual approximated the same properties resonably. Moreover, the determined realization bundle showed that the study field initially had 151.5 million m3 (cubic meter) of gas and 1.04 million m3 water in the coal, corresponding to Q90 of the entire range of probability for gas and close to Q75 for water. In 2013, in-place fluid amounts decreased to 138.9 million m3 and 0.997 million m3 for gas and water, respectively. PMID:29563647

Applying robust design to study the effects of stratigraphic characteristics on brittle failure and bump potential in a coal mine

PubMed Central

Kim, Bo-Hyun; Larson, Mark K.; Lawson, Heather E.

2018-01-01

Bumps and other types of dynamic failure have been a persistent, worldwide problem in the underground coal mining industry, spanning decades. For example, in just five states in the U.S. from 1983 to 2014, there were 388 reportable bumps. Despite significant advances in mine design tools and mining practices, these events continue to occur. Many conditions have been associated with bump potential, such as the presence of stiff units in the local geology. The effect of a stiff sandstone unit on the potential for coal bumps depends on the location of the stiff unit in the stratigraphic column, the relative stiffness and strength of other structural members, and stress concentrations caused by mining. This study describes the results of a robust design to consider the impact of different lithologic risk factors impacting dynamic failure risk. Because the inherent variability of stratigraphic characteristics in sedimentary formations, such as thickness, engineering material properties, and location, is significant and the number of influential parameters in determining a parametric study is large, it is impractical to consider every simulation case by varying each parameter individually. Therefore, to save time and honor the statistical distributions of the parameters, it is necessary to develop a robust design to collect sufficient sample data and develop a statistical analysis method to draw accurate conclusions from the collected data. In this study, orthogonal arrays, which were developed using the robust design, are used to define the combination of the (a) thickness of a stiff sandstone inserted on the top and bottom of a coal seam in a massive shale mine roof and floor, (b) location of the stiff sandstone inserted on the top and bottom of the coal seam, and (c) material properties of the stiff sandstone and contacts as interfaces using the 3-dimensional numerical model, FLAC3D. After completion of the numerical experiments, statistical and multivariate analysis are performed using the calculated results from the orthogonal arrays to analyze the effect of these variables. As a consequence, the impact of each of the parameters on the potential for bumps is quantitatively classified in terms of a normalized intensity of plastic dissipated energy. By multiple regression, the intensity of plastic dissipated energy and migration of the risk from the roof to the floor via the pillars is predicted based on the value of the variables. The results demonstrate and suggest a possible capability to predict the bump potential in a given rock mass adjacent to the underground excavations and pillars. Assessing the risk of bumps is important to preventing fatalities and injuries resulting from bumps. PMID:29416902

Longwall gate road stability in a steeply pitching thick coal seam with a weak roof. Report of investigations/1995

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barron, L.R.; DeMarco, M.J.

1995-12-31

The U.S. Bureau of Mines conducted a ground pressure analysis of a wide abutment-type chain pillar in a two-entry gate road of a Western U.S. coal mine with an extremely weak immediate roof. This report discusses gate road layout and performance and secondary support effectiveness. The results of the pillar pressure study are compared to pillar loading predicted by a widely used pillar design method and to similar studies in other mines. A stability evaluation of the most recent longwall headgate, using the USBM Analysis of Longwall Pillar Stability (ALPS) indicates marginal stability in first-panel mining and instability in second-panelmore » mining. ALPS and the USBM Coal Mine Roof Rating (CMRR) system are used to evaluate tailgate-mining stability of the previous gate roads and to determine pillar and entry width and top coal thickness criteria for tailgate stability in future panels.« less

Pillar size optimization design of isolated island panel gob-side entry driving in deep inclined coal seam—case study of Pingmei No. 6 coal seam

NASA Astrophysics Data System (ADS)

Zhang, Shuai; Wang, Xufeng; Fan, Gangwei; Zhang, Dongsheng; Jianbin, Cui

2018-06-01

There is a perception that deep roadways are difficult to maintain. To reverse this and to improve the recovery rate of coal resources, gob-side entry driving is widely used in coal mines, especially deep-mining coal mines, in China. Determination of the reasonable pillar size through in situ observation and experimentation plays a vital role for roadway maintenance. Based on the geological conditions of Pingmei No.6 coal seam, a theoretical analysis, numerical simulation, and industrial experiments are carried out to calculate the reasonable width of chain pillars, analyze the lateral support stress distribution law near the gob side, investigate the relationship between the coal pillar stress distribution, roadway surrounding rock stress distribution, roadway surrounding rock deformation and the coal pillar width. The results indicate that 5 m wide coal pillars can ensure that the chain pillars are at a lower stress level and the deformation of roadway surrounding rock is in a more reasonable range. Industrial experiments show that when the chain pillar width is 5 m, the deformation of roadway surrounding rock can meet the requirements of working face safe production. The numerical results agreed well with field measurement and observations, and the industrial experiments results further validated the results of the numerical simulation.

Coal-Face Fracture With A Two-Phase Liquid

NASA Technical Reports Server (NTRS)

Collins, E. R., Jr.

1985-01-01

In new method for mining coal without explosive, two-phase liquid such as CO2 and water, injected at high pressure into deeper ends of holes drilled in coal face. Liquid permeates coal seam through existing microfractures; as liquid seeps back toward face, pressure eventually drops below critical value at which dissolved gas flashvaporizes, breaking up coal.

46 CFR 160.049-4 - Construction and workmanship.

Code of Federal Regulations, 2010 CFR

2010-10-01

... or less in each layer, cemented together with an all-purpose vinyl adhesive such as or equivalent to U.S. Rubber No. M-6256 or Minnesota Mining No. EC-870 and No. EC-1070; (ii) Three layers or less that may be cemented; and (iii) Staggered butts and seams of adjacent layers. (d) Grab Straps. Grab...

Studies of the phytoplankton and soil algae of two strip-mine impoundments in Tuscarawas County, Ohio

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richards, J.N.

1973-01-01

The process of strip-mining leaves vast areas that are denuded of vegetation and are open to primary succession by organisms such as algae. Acid strip-mine impoundments are either formed by man-made or natural processes. These impoundments are remnants of old strip-mine pits that have been filled with runoff water. The water chemistry of these ponds reflects the chemistry of the earth strata above the coal seam that was mined. These young impoundments or ponds are extremely low in pH and quite acidic due to the presence of great amounts of sulfuric acid. Algae that are found in these types ofmore » habitats exhibit a tolerance to acid conditions and are considered to be acidophilic. Few species of algae are known to be common componenets of these habitats.« less

From in-situ coal to fly ash: A study of coal mines and power plants from Indiana

USGS Publications Warehouse

Mastalerz, Maria; Hower, J.C.; Drobniak, A.; Mardon, S.M.; Lis, G.

2004-01-01

This paper presents data on the properties of coal and fly ash from two coal mines and two power plants that burn single-source coal from two mines in Indiana. One mine is in the low-sulfur (5%) Springfield Coal Member of the Petersburg Formation (Pennsylvanian). Both seams have comparable ash contents (???11%). Coals sampled at the mines (both raw and washed fractions) were analyzed for proximate/ultimate/sulfur forms/heating value, major oxides, trace elements and petrographic composition. The properties of fly ash from these coals reflect the properties of the feed coal, as well as local combustion and post-combustion conditions. Sulfur and spinel content, and As, Pb and Zn concentrations of the fly ash are the parameters that most closely reflect the properties of the source coal. ?? 2004 Elsevier B.V. All rights reserved.

Forecasting of Energy Expenditure of Induced Seismicity with Use of Artificial Neural Network

NASA Astrophysics Data System (ADS)

Cichy, Tomasz; Banka, Piotr

2017-12-01

Coal mining in many Polish mines in the Upper Silesian Coal Basin is accompanied by high levels of induced seismicity. In mining plants, the methods of shock monitoring are improved, allowing for more accurate localization of the occurring phenomena and determining their seismic energy. Equally important is the development of ways of forecasting seismic hazards that may occur while implementing mine design projects. These methods, depending on the length of time for which the forecasts are made, can be divided into: longterm, medium-term, short-term and so-called alarm. Long-term forecasts are particularly useful for the design of seam exploitations. The paper presents a method of predicting changes in energy expenditure of shock using a properly trained artificial neural network. This method allows to make long-term forecasts at the stage of the mine’s exploitation design, thus enabling the mining work plans to be reviewed to minimize the potential for tremors. The information given at the input of the neural network is indicative of the specific energy changes of the elastic deformation occurring in the selected, thick, resistant rock layers (tremor-prone layers). Energy changes, taking place in one or more tremor-prone layers are considered. These indicators describe only the specific energy changes of the elastic deformation accumulating in the rock as a consequence of the mining operation, but does not determine the amount of energy released during the destruction of a given volume of rock. In this process, the potential energy of elastic strain transforms into other, non-measurable energy types, including the seismic energy of recorded tremors. In this way, potential energy changes affect the observed induced seismicity. The parameters used are characterized by increases (declines) of specific energy with separation to occur before the hypothetical destruction of the rock and after it. Additional input information is an index characterizing the rate of tectonic faults. This parameter was not included in previous research by authors. At the output of the artificial neural network, the values of the energy density of the mining tremors [J/m3] are obtained. An example of the predicted change in seismicity induced for a highly threatened region is presented. Relatively good predicted and observed energy expenditure of tremors was obtained. The presented method can complement existing methods (analytical and geophysical) forecasting seismic hazard. This method can be used primarily in those areas where the seismic level is determined by the configuration of the edges and residues in the operating seam, as well as in adjacent seams, and to a lesser extent, the geological structure of the rock The method is local, it means that the artificial neural network prediction can only be performed for the region from which the data have been used for its originated learning. The developed method cannot be used in areas where mining is just beginning and it is not possible to predict the level of seismicity induced in areas where no mining tremors have been recorded so far.

Loss of effectiveness of protective clothing after its use in pesticide sprays and its multiple washes.

PubMed

Espanhol-Soares, Melina; Teodoro de Oliveira, Manuela; Machado-Neto, Joaquim Gonçalves

2017-02-01

Protective clothing is used as a barrier against pesticides when working with agricultural sprays. The aim of this study was to evaluate the pesticide penetration, retention, and repellence of the material and seams of a whole-body protective garment used by applicators of pesticides. The efficiency of the material and seams of the whole-body garment were determined for its classification as proposed by ISO 27065 (ISO, 2011). The evaluation method used was the pipette test of ISO 22608. The efficiency of the material and seams of the garment (100% cotton) were tested by contamination with formulations of Roundup Original® SL; Nufos EC® and Supera SC®. The presence of the seams in the protective clothing reduced its efficiency in the control of dermal exposure, except when protecting against the Supera SC® formulation. The number of washes and uses affected the efficiency of the material and seams of the garment. The type of formulation interfered significantly in the penetration of pesticides into the material and seams. Thus, the laboratory efficiency assessment of protective clothing is necessary to determine what types of formulations and use conditions are appropriate for workers.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Thompson, D.

The coal seams uplifted by the Perija and Sierra Nevada de Santa marta Mountains along the border of Colombia and Venezuela are high quality reserves with low mining ratios that are in close proximity to the coast. Since the late 70`s and early 80`s, various mining developments have increased the production of these reserves to its current level of 37 million tons per year. Most of the production is shipped to European and to North and South American markets. Further exploitation of these reserves will require significant investments in mine development, inland transportation, and port facilities. This paper will summarizemore » the current status of the Colombian and Venezuelan coal industry, as well as the potential and challenges for increased production and exportation.« less

A Unified Overset Grid Generation Graphical Interface and New Concepts on Automatic Gridding Around Surface Discontinuities

NASA Technical Reports Server (NTRS)

Chan, William M.; Akien, Edwin (Technical Monitor)

2002-01-01

For many years, generation of overset grids for complex configurations has required the use of a number of different independently developed software utilities. Results created by each step were then visualized using a separate visualization tool before moving on to the next. A new software tool called OVERGRID was developed which allows the user to perform all the grid generation steps and visualization under one environment. OVERGRID provides grid diagnostic functions such as surface tangent and normal checks as well as grid manipulation functions such as extraction, extrapolation, concatenation, redistribution, smoothing, and projection. Moreover, it also contains hyperbolic surface and volume grid generation modules that are specifically suited for overset grid generation. It is the first time that such a unified interface existed for the creation of overset grids for complex geometries. New concepts on automatic overset surface grid generation around surface discontinuities will also be briefly presented. Special control curves on the surface such as intersection curves, sharp edges, open boundaries, are called seam curves. The seam curves are first automatically extracted from a multiple panel network description of the surface. Points where three or more seam curves meet are automatically identified and are called seam corners. Seam corner surface grids are automatically generated using a singular axis topology. Hyperbolic surface grids are then grown from the seam curves that are automatically trimmed away from the seam corners.

Optimizing longwall mine layouts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Minkel, M.J.

1996-12-31

Before spending the time to design an underground mine in detail, the mining engineer should be assured of the economic viability of the location of the layout. This has historically been a trial-and-error, iterative process. Traditional underground mine planning usually bases the layout on the geological characteristics of a deposit such as minimum seam height, quality, and the absence of faults. Whether one attempts to make a decision manually. or use traditional mine planning software, the process works something like this: First you build geological model. Then you impose a {open_quotes}best guess{close_quotes} as to which geological layers will become partmore » of the mined product, or will influence mining. Next you place your design where you believe is the best location to make a mine. Then you select equipment which you believe will cost-effectively mine the area. Finally, you schedule your equipment selection through the design over the mine life, run financial analyses and see if the rate of return is acceptable. If the NPV is acceptable, the design is accepted. If the NPV is not acceptable, the engineer has to restart the cycle of redesigning the layout, rescheduling the equipment, and restudying the economics again.« less

A review of nickel toxicity to marine and estuarine tropical biota with particular reference to the South East Asian and Melanesian region.

PubMed

Gissi, Francesca; Stauber, Jennifer L; Binet, Monique T; Golding, Lisa A; Adams, Merrin S; Schlekat, Christian E; Garman, Emily R; Jolley, Dianne F

2016-11-01

The South East Asian Melanesian (SEAM) region contains the world's largest deposits of nickel lateritic ores. Environmental impacts may occur if mining operations are not adequately managed. Effects data for tropical ecosystems are required to assess risks of contaminant exposure and to derive water quality guidelines (WQG) to manage these risks. Currently, risk assessment tools and WQGs for the tropics are limited due to the sparse research on how contaminants impact tropical biota. As part of a larger project to develop appropriate risk assessment tools to ensure sustainable nickel production in SEAM, nickel effects data were required. The aim of this review was to compile data on the effects of nickel on tropical marine, estuarine, pelagic and benthic species, with a particular focus on SEAM. There were limited high quality chronic nickel toxicity data for tropical marine species, and even fewer for those relevant to SEAM. Of the data available, the most sensitive SEAM species to nickel were a sea urchin, copepod and anemone. There is a significant lack of high quality chronic data for several ecologically important taxonomic groups including cnidarians, molluscs, crustaceans, echinoderms, macroalgae and fish. No high quality chronic nickel toxicity data were available for estuarine waters or marine and estuarine sediments. The very sparse toxicity data for tropical species limits our ability to conduct robust ecological risk assessment and may require additional data generation or read-across from similar species in other databases (e.g. temperate) to fill data gaps. Recommendations on testing priorities to fill these data gaps are presented. Copyright © 2016 Elsevier Ltd. All rights reserved.

Hydromechanical planer with cutting and breaking heads

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goris, H.; Gunther, R.; Ogorek, K.

1980-12-16

A hydromatic planer particularly for mining materials in a mining seam is comprised of a planer housing which advantageously has a cutting and breaking head on each end thereof, each of which includes a substantially identical construction. Each cutting head includes a vertically arranged support member which is mounted on the housing of the planer by a parallel linkage so that it may be moved upwardly and downwardly under the control of an adjustment means such as a fluid pressure operated piston and cylinder combination. Each cutting and breaking head also includes a first substantially vertically arranged support member whichmore » is connected by the linkage for upward and downward movement relative to the housing and a second support member which is movable relative to the first and mounted on this first in vertical guides for upward and downward movement. A second fluid pressure operated piston and cylinder combination is connected between first and second support members so that they may be shifted relative to each other. A second support member advantageously carries a cutting and breaking wedge which is oriented to engage the mining seam, for example, on a side thereof, and which may be adjusted relative to a similarly oriented cutting and breaking wedge carried by the first member. In addition, a separate cutting and breaking wedge is carried by the first member and it may be engaged for example against the floor thereof in a plane different from the other two wedges.« less

Structural analysis of the Tabaco anticline, Cerrejón open-cast coal mine, Colombia, South America

NASA Astrophysics Data System (ADS)

Cardozo, Néstor; Montes, Camilo; Marín, Dora; Gutierrez, Iván; Palencia, Alejandro

2016-06-01

The Tabaco anticline is a 15 km long, south plunging, east-vergent anticline in northern Colombia, close to the transpressional collisional margin between the Caribbean and South American plates. In the Cerrejón open-cast coal mine, systematic mapping of coal seams in the middle to upper Paleocene Cerrejón Formation has yielded an exceptional dataset consisting of 10 horizontal slices (sea level to 90 m elevation, regularly spaced at 10 m intervals) through the anticline. Coal seams and fault traces in these slices are used to construct a 3D model of the anticline. This 3D model shows tighter folds within lower coal seams, NW-vergent thrusts and related folds on the gentler western limb, and strike-slip faults on the steeper eastern limb. Fault slip-tendency analysis is used to infer that these two faulting styles resulted from two different stress fields: an earlier one consistent with thrusting and uplift of the Perijá range, and a later one consistent with strike-slip faulting (Oca, Ranchería and Samán faults). Our preferred interpretation is that the anticline developed its eastern vergence during the early stages (late Paleocene-early Eocene) of tilting of the Santa Marta massif. Later NW-vergent thrusting on the western limb (early to middle Eocene) was related to western propagation of the Perijá thrust system. These results contribute to the understanding of the structural evolution of the area. They are also a good example of the complex interplay between detachment folding, thrusting, and strike-slip faulting during the growth of a km-size fold in a transpressive setting.

Bioregional Assessments: Determining the Impacts of Coal Resource Development on Water Resources in Australia through Groundwater, Surface Water and Ecological Modelling

NASA Astrophysics Data System (ADS)

Peeters, L. J.; Post, D. A.; Crosbie, R.; Holland, K.

2017-12-01

While extraction of methane from shale gas deposits has been the principal source of the recent expansion of the industry in the United States, in Australia extraction of methane from coal bed methane deposits (termed `coal seam gas' in Australia) has been the focus to date. The two sources of methane share many of the same characteristics including the potential requirement for hydraulic fracturing. However, as coal seam gas deposits generally occur at shallower depths than shale gas, the potential impacts of extraction on surface and groundwater resources may be of even greater concern. The Australian Federal Government commissioned a multi-disciplinary programme of bioregional assessments to improve understanding of the potential impacts of coal seam gas and large coal mining activities on water resources and water-dependent assets across six bioregions Australia. A bioregional assessment is a transparent scientific analysis of the ecology, hydrology, geology and hydrogeology of a bioregion with explicit assessment of the potential direct, indirect and cumulative impacts of coal seam gas and large coal mining development on water resources. The first step in the analysis is to establish the most likely scenario for coal development in each region and establish a causal pathway linking coal development to impacts to the social, economic and ecological functioning of water resources. This forms the basis for a sequence of probabilistic geological, hydrogeological, hydrological and ecological models to quantify the probability of potential impacts. This suite of models is developed independent of the proponents and regulators of coal resource developments and so can provide unbiased information to all stakeholders. To demonstrate transparency of the modelling, all inputs, outputs and executables will be available from http://www.bioregionalassessments.gov.au. The analysis delineated a zone of potential hydrological change for each region, outside of which impacts from coal development are very unlikely. Within each zone, the analysis provides a regional estimate of the likely impacts and identifies the major knowledge and data gaps. This information provides a framework for further local study.

Study on the special vision sensor for detecting position error in robot precise TIG welding of some key part of rocket engine

NASA Astrophysics Data System (ADS)

Zhang, Wenzeng; Chen, Nian; Wang, Bin; Cao, Yipeng

2005-01-01

Rocket engine is a hard-core part of aerospace transportation and thrusting system, whose research and development is very important in national defense, aviation and aerospace. A novel vision sensor is developed, which can be used for error detecting in arc length control and seam tracking in precise pulse TIG welding of the extending part of the rocket engine jet tube. The vision sensor has many advantages, such as imaging with high quality, compactness and multiple functions. The optics design, mechanism design and circuit design of the vision sensor have been described in detail. Utilizing the mirror imaging of Tungsten electrode in the weld pool, a novel method is proposed to detect the arc length and seam tracking error of Tungsten electrode to the center line of joint seam from a single weld image. A calculating model of the method is proposed according to the relation of the Tungsten electrode, weld pool, the mirror of Tungsten electrode in weld pool and joint seam. The new methodologies are given to detect the arc length and seam tracking error. Through analyzing the results of the experiments, a system error modifying method based on a linear function is developed to improve the detecting precise of arc length and seam tracking error. Experimental results show that the final precision of the system reaches 0.1 mm in detecting the arc length and the seam tracking error of Tungsten electrode to the center line of joint seam.

Performance evaluation of a cable bolted yield-abutment gate road system at the Crandall Canyon No. 1 Mine, Genwal Resources, Inc., Huntington, Utah

DOE Office of Scientific and Technical Information (OSTI.GOV)

Koehler, J.R.; DeMarco, M.J.; Marshall, R.J.

1996-12-01

Although two-entry yield pillar-based gate roads supported by wooden cribs have been commonly used throughout longwalling in the Wasatch Plateau/Roan Cliffs coalfield of central Utah, a three-entry yield-abutment gate road configuration was recently trialed in the Hiawatha Seam at the Genwal Resources (GRI) Crandall Canyon No. 1 Mine, near Huntington, UT. Pillar, entry, and cable bolt performance were monitored through second panel mining using a fairly extensive array of geomechanical instruments installed over a span of four crosscuts. Ground pressure and entry closure measurements confirmed that the 9.1-m-wide (30-ft) yield pillar was partially shielded from first panel longwall loads bymore » the 36.6-m-wide (120-ft) abutment pillar, and consequently, experienced only minor yielding until the approach of the second panel face. Complete yielding of the 9.1-m-wide (30-ft) pillar occurred when the second panel was approximately 6.1 m (20 ft) in by the instrumentation site. Average cable bolt loads and differential roof sag remained low through second panel mining and tailgate entry ground conditions were excellent; however, very high ground pressures in the abutment and yield pillars, and second panel rib strongly suggest a high potential for coal bumps utilizing this gate road configuration at mining cover depths in excess of 396 to 457 m (1300 to 1500 ft). This conclusion is supported by the suspected occurrence of small coal bumps along the abutment pillar ribs, observed indirectly as fresh debris in the middle entry just behind the second face. This paper presents a case history developed from the geotechnical measurements and on-site observations of this unique application of a yield-abutment gate road configuration and cable support system in the Hiawatha Seam.« less

Line Segmentation in Handwritten Assamese and Meetei Mayek Script Using Seam Carving Based Algorithm

NASA Astrophysics Data System (ADS)

Kumar, Chandan Jyoti; Kalita, Sanjib Kr.

Line segmentation is a key stage in an Optical Character Recognition system. This paper primarily concerns the problem of text line extraction on color and grayscale manuscript pages of two major North-east Indian regional Scripts, Assamese and Meetei Mayek. Line segmentation of handwritten text in Assamese and Meetei Mayek scripts is an uphill task primarily because of the structural features of both the scripts and varied writing styles. Line segmentation of a document image is been achieved by using the Seam carving technique, in this paper. Researchers from various regions used this approach for content aware resizing of an image. However currently many researchers are implementing Seam Carving for line segmentation phase of OCR. Although it is a language independent technique, mostly experiments are done over Arabic, Greek, German and Chinese scripts. Two types of seams are generated, medial seams approximate the orientation of each text line, and separating seams separated one line of text from another. Experiments are performed extensively over various types of documents and detailed analysis of the evaluations reflects that the algorithm performs well for even documents with multiple scripts. In this paper, we present a comparative study of accuracy of this method over different types of data.

Underground coal operators install several new longwall mining systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fiscor, S.

2008-02-15

Several new names appear in the annual US Longwall Census, but the population remains the same: 52 although the number of longwall mines dropped from 40 to 47. CONSOL Energy remains the leader with 12 faces. Robert E. Murray owns 8 longwall mines followed by Arch Coal with 5 and Foundation Coal with 3. West Virginia has 13 longwalls followed by 9 in Pennsylvania, 7 in Utah and 6 in Alabama. The article describes CONSOL Energy's operations. A detailed table gives for each longwall installation, the ownership, seam height, cutting height, panel width and length, overburden, number of gate entries,more » depth of cut, model of equipment used (shearer, haulage system, roof support, face conveyor, stage loader, crusher, electrical controls and voltage to face). 2 tabs.« less

Key Technologies and Applications of Gas Drainage in Underground Coal Mine

NASA Astrophysics Data System (ADS)

Zhou, Bo; Xue, Sheng; Cheng, Jiansheng; Li, Wenquan; Xiao, Jiaping

2018-02-01

It is the basis for the long-drilling directional drilling, precise control of the drilling trajectory and ensuring the effective extension of the drilling trajectory in the target layer. The technology can be used to complete the multi-branch hole construction and increase the effective extraction distance of the coal seam. The gas drainage and the bottom grouting reinforcement in the advanced area are realized, and the geological structure of the coal seam can be proved accurately. It is the main technical scheme for the efficient drainage of gas at home and abroad, and it is applied to the field of geological structure exploration and water exploration and other areas. At present, the data transmission method is relatively mature in the technology and application, including the mud pulse and the electromagnetic wave. Compared with the mud pulse transmission mode, the electromagnetic wave transmission mode has obvious potential in the data transmission rate and drilling fluid, and it is suitable for the coal mine. In this paper, the key technologies of the electromagnetic wave transmission mode are analyzed, including the attenuation characteristics of the electromagnetic transmission channel, the digital modulation scheme, the channel coding method and the weak signal processing technology. A coal mine under the electromagnetic wave drilling prototype is developed, and the ground transmission experiments and down hole transmission test are carried out. The main work includes the following aspects. First, the equivalent transmission line method is used to establish the electromagnetic transmission channel model of coal mine drilling while drilling, and the attenuation of the electromagnetic signal is measured when the electromagnetic channel measured. Second, the coal mine EM-MWD digital modulation method is developed. Third, the optimal linear block code which suitable for EM-MWD communication channel in coal mine is proposed. Fourth, the noise characteristics of well near horizontal directional drilling are analyzed, and the multi-stage filter method is proposed to suppress the natural potential and strong frequency interference signal. And the weak electromagnetic communication signal is extracted from the received signal. Finally, the detailed design of the electromagnetic wave while drilling is given.

Method for assessing coal-floor water-inrush risk based on the variable-weight model and unascertained measure theory

NASA Astrophysics Data System (ADS)

Wu, Qiang; Zhao, Dekang; Wang, Yang; Shen, Jianjun; Mu, Wenping; Liu, Honglei

2017-11-01

Water inrush from coal-seam floors greatly threatens mining safety in North China and is a complex process controlled by multiple factors. This study presents a mathematical assessment system for coal-floor water-inrush risk based on the variable-weight model (VWM) and unascertained measure theory (UMT). In contrast to the traditional constant-weight model (CWM), which assigns a fixed weight to each factor, the VWM varies with the factor-state value. The UMT employs the confidence principle, which is more effective in ordered partition problems than the maximum membership principle adopted in the former mathematical theory. The method is applied to the Datang Tashan Coal Mine in North China. First, eight main controlling factors are selected to construct the comprehensive evaluation index system. Subsequently, an incentive-penalty variable-weight model is built to calculate the variable weights of each factor. Then, the VWM-UMT model is established using the quantitative risk-grade divide of each factor according to the UMT. On this basis, the risk of coal-floor water inrush in Tashan Mine No. 8 is divided into five grades. For comparison, the CWM is also adopted for the risk assessment, and a differences distribution map is obtained between the two methods. Finally, the verification of water-inrush points indicates that the VWM-UMT model is powerful and more feasible and reasonable. The model has great potential and practical significance in future engineering applications.

Longwall top coal caving (LTCC) mining technologies with roof softening by hydraulic fracturing method

NASA Astrophysics Data System (ADS)

Klishin, V.; Nikitenko, S.; Opruk, G.

2018-05-01

The paper discusses advanced top coal caving technologies for thick coal seams and addresses some issues of incomplete coal extraction, which can result in the environmental damage, landscape change, air and water pollution and endogenous fires. The authors put forward a fundamentally new, having no equivalent and ecology-friendly method to difficult-to-cave roof coal – directional hydraulic fracturing and nonexplosive disintegration.

Stress analysis of three-dimensional roadway layout of stagger arrangement with field observation

NASA Astrophysics Data System (ADS)

Cui, Zimo; Chanda, Emmanuel; Zhao, Jingli; Wang, Zhihe

2018-01-01

Longwall top-coal caving (LTCC) has been a popular, more productive and cost-effective method for extracting thick (> 5 m) to ultra-thick coal seams in recent years. However, low-level recovery ratio of coal resources and top-coal loss above the supports at both ends of working face are long-term problems. Geological factors, such as large dip angle, soft rock, mining depth further complicate the problems. This paper proposes addressing this issue by adopting three-dimensional roadway layout of stagger arrangement (3-D RLSA). In this study, the first step was to analyse the stress environment surrounding head entry in the replacing working face based on the stress distribution characteristics at the triangular coal-pillar side in gob and the stress slip line field theory. In the second step, filed observation was conducted. Finally, an economic evaluation of the 3-D RLSA for extracting thick to ultra-thick seams was conducted.

Convergence at the faces of development workings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borisenko, A.A.

1977-07-01

Since 1963 we have been carrying out investigations in pits of the Pechora coalfield to establish the general laws of roof-floor convergence in the face areas of development workings and their role in gas bursts. We also considered how various methods of working on the seam influence the amount of type of convergence. The observations were made in 20 workings in five pits of Vorkutaugol Group, cut by cutter-loaders and by drilling and blasting at depths between 350 and 600 m; the cross-sectional areas of the workings ranged frm 3.7 to 12.0 m/sup 2/. The aggregated data on daily convergencemore » values was analyzed by the multiple correlation method with the aid of a computer. The aim of the analysis was to elucidate the influence of six factors on the daily convergence values: the depth below the surface, the corrected seam strength, the cross-sectional area of the working, the initial distance from the face to the measurement prop, the daily advance, and the thickness of the seam. The combined correlation coefficient was rather low - 0.49 with a reliability of 9.13. The greatest influence on the convergence values is exerted by the cross-sectional area and by the distance from the face (the partial correlation coefficients being 0.281 and 0.310, respectively), and lesser influences are exerted by the depth below the surface and by the corrected strength of the seam (partial correlationcoefficients 0.164 and 0.178); the influences of seam thickness and daily face advance are very slight. The multiple correlation results indicate that a very great influence is exerted by disregarded factors, among which the most important are undoubtedly the properties of the surrounding rocks.« less

Coal Mine Roadway Stability in Soft Rock: A Case Study

NASA Astrophysics Data System (ADS)

Shen, Baotang

2014-11-01

Roadway instability has always been a major concern in deep underground coal mines where the surrounding rock strata and coal seams are weak and the in situ stresses are high. Under the high overburden and tectonic stresses, roadways could collapse or experience excessive deformation, which not only endangers mining personnel but could also reduce the functionality of the roadway and halt production. This paper describes a case study on the stability of roadways in an underground coal mine in Shanxi Province, China. The mine was using a longwall method to extract coal at a depth of approximately 350 m. Both the coal seam and surrounding rock strata were extremely weak and vulnerable to weathering. Large roadway deformation and severe roadway instabilities had been experienced in the past, hence, an investigation of the roadway failure mechanism and new support designs were needed. This study started with an in situ stress measurement programme to determine the stress orientation and magnitude in the mine. It was found that the major horizontal stress was more than twice the vertical stress in the East-West direction, perpendicular to the gateroads of the longwall panel. The high horizontal stresses and low strength of coal and surrounding rock strata were the main causes of roadway instabilities. Detailed numerical modeling was conducted to evaluate the roadway stability and deformation under different roof support scenarios. Based on the modeling results, a new roadway support design was proposed, which included an optimal cable/bolt arrangement, full length grouting, and high pre-tensioning of bolts and cables. It was expected the new design could reduce the roadway deformation by 50 %. A field experiment using the new support design was carried out by the mine in a 100 m long roadway section. Detailed extensometry and stress monitorings were conducted in the experimental roadway section as well as sections using the old support design. The experimental section produced a much better roadway profile than the previous roadway sections. The monitoring data indicated that the roadway deformation in the experimental section was at least 40-50 % less than the previous sections. This case study demonstrated that through careful investigation and optimal support design, roadway stability in soft rock conditions can be significantly improved.

Overall requirements for an advanced underground coal extraction system. [environment effects, miner health and safety, production cost, and coal conservation

NASA Technical Reports Server (NTRS)

Goldsmith, M.; Lavin, M. L.

1980-01-01

Underground mining systems suitable for coal seams expoitable in the year 2000 are examined with particular relevance to the resources of Central Appalachia. Requirements for such systems may be summarized as follows: (1) production cost; (2)miner safety; (3) miner health; (4) environmental impact; and (5) coal conservation. No significant trade offs between production cost and other performance indices were found.

The environmental costs of mountaintop mining valley fill operations for aquatic ecosystems of the Central Appalachians.

PubMed

Bernhardt, Emily S; Palmer, Margaret A

2011-03-01

Southern Appalachian forests are recognized as a biodiversity hot spot of global significance, particularly for endemic aquatic salamanders and mussels. The dominant driver of land-cover and land-use change in this region is surface mining, with an ever-increasing proportion occurring as mountaintop mining with valley fill operations (MTVF). In MTVF, seams of coal are exposed using explosives, and the resulting noncoal overburden is pushed into adjacent valleys to facilitate coal extraction. To date, MTVF throughout the Appalachians have converted 1.1 million hectares of forest to surface mines and buried more than 2,000 km of stream channel beneath mining overburden. The impacts of these lost forests and buried streams are propagated throughout the river networks of the region as the resulting sediment and chemical pollutants are transmitted downstream. There is, to date, no evidence to suggest that the extensive chemical and hydrologic alterations of streams by MTVF can be offset or reversed by currently required reclamation and mitigation practices. © 2011 New York Academy of Sciences.

Prediction of groundwater inrush into coal mines from aquifers underlying the coal seams in China: application of vulnerability index method to Zhangcun Coal Mine, China

NASA Astrophysics Data System (ADS)

Wu, Qiang; Zhou, Wanfang; Wang, Jinhua; Xie, Shuhan

2009-05-01

Groundwater inrush is a geohazard that can significantly impact safe operations of the coal mines in China. Its occurrence is controlled by many factors and processes are often not amenable to mathematical expressions. To evaluate the water inrush risk, Professor Wu and his colleagues have proposed the vulnerability index approach by coupling the artificial neural network (ANN) and geographic information system (GIS). The detailed procedures of using this innovative approach are shown in a case study. Firstly, the powerful spatial data analysis functions of GIS was used to establish the thematic layer of each of the main factors that control the water inrush, and then to choose the training sample on the thematic layer with the ANN-BP Arithmetic. Secondly, the ANN evaluation model of the water inrush was established to determine the threshold value for each risk level with a histogram of the water inrush vulnerability index. As a result, the mine area was divided into four regions with different vulnerability levels and they served as the general guidelines for the mine operations.

CoalVal-A coal resource valuation program

USGS Publications Warehouse

Rohrbacher, Timothy J.; McIntosh, Gary E.

2010-01-01

CoalVal is a menu-driven Windows program that produces cost-of-mining analyses of mine-modeled coal resources. Geological modeling of the coal beds and some degree of mine planning, from basic prefeasibility to advanced, must already have been performed before this program can be used. United States Geological Survey mine planning is done from a very basic, prefeasibility standpoint, but the accuracy of CoalVal's output is a reflection of the accuracy of the data entered, both for mine costs and mine planning. The mining cost analysis is done by using mine cost models designed for the commonly employed, surface and underground mining methods utilized in the United States. CoalVal requires a Microsoft Windows? 98 or Windows? XP operating system and a minimum of 1 gigabyte of random access memory to perform operations. It will not operate on Microsoft Vista?, Windows? 7, or Macintosh? operating systems. The program will summarize the evaluation of an unlimited number of coal seams, haulage zones, tax entities, or other area delineations for a given coal property, coalfield, or basin. When the reader opens the CoalVal publication from the USGS website, options are provided to download the CoalVal publication manual and the CoalVal Program. The CoalVal report is divided into five specific areas relevant to the development and use of the CoalVal program: 1. Introduction to CoalVal Assumptions and Concepts. 2. Mine Model Assumption Details (appendix A). 3. CoalVal Project Tutorial (appendix B). 4. Program Description (appendix C). 5. Mine Model and Discounted Cash Flow Formulas (appendix D). The tutorial explains how to enter coal resource and quality data by mining method; program default values for production, operating, and cost variables; and ones own operating and cost variables into the program. Generated summary reports list the volume of resource in short tons available for mining, recoverable short tons by mining method; the seam or property being mined; operating cost per ton; and discounted cash flow cost per ton to mine and process the resources. Costs are calculated as loaded in a unit train, free-on-board the tipple, at a rate of return prescribed by the evaluator. The recoverable resources (in short tons) may be grouped by incremental cost over any range chosen by the user. For example, in the Gillette coalfield evaluation, the discounted cash flow mining cost (at an 8 percent rate of return) and its associated tonnage may be grouped by any applicable increment (for example, $0.10 per ton, $0.20 per ton, and so on) and using any dollar per ton range that is desired (for example, from $4.00 per ton to $15.00 per ton). This grouping ability allows the user to separate the coal reserves from the nonreserve resources and to construct cost curves to determine the effects of coal market fluctuations on the availability of coal for fuel whether for the generation of electricity or for coal-to-liquids processes. Coking coals are not addressed in this report.

Petrography of Permian "Gondwana" coals from boreholes in northwestern Bangladesh, based on semiautomated reflectance scanning

USGS Publications Warehouse

Bostick, N.H.; Betterton, W.J.; Gluskoter, H.J.; Nazrul, Islam M.

1991-01-01

Drilling through Quaternary alluvium and Tertiary cover at low-gravity anomalies in northwestern Bangladesh showed the presence of Permian sedimentary rocks in depressions that may be as much as a thousand meters deep in the crystalline basement. These Permian strata include low-sulfur, high-volatile bituminous coals in beds as thick as 15 m. The maceral group composition of these coals was determined by semiautomated reflectance scanning with a motorized microscope stage, rather than by point counting. This method was chosen to give objectively recorded raw analytical data and to provide a graphical picture of each sample. The coals are mostly "Gondwana" type (poorly layered "plum pudding" with abundant minerals and inertinite in a vitrinite groundmass) that would be classed as semi-dull (inerto-gelitite) coals. However, six samples have more than 70% vitrinite. None of the samples would be classed as sapropelic (liptinitic). The upper, middle, and lower main seams in borehole GDH-45 were sampled in 10 benches (0.1-3 m thick) each. Inertinite ranges from 7 to 100 vol% (mineral free basis) in individual benches, but composite seam averages are 41, 54 and 67%. Inertinite increases toward the top of two main seams so the bottom would yield the most valuable first mine slices. Some benches with extremely high inertinite content, such as the top 7 m of the lower thick seam, might be mined specially for blending with foreign low-inert coals to increase coke strength. The free swelling index reaches 7.5 in several vitrinite-rich benches, which can indicate good coking coal. Much of the vitrinite is fluorescent, which indicates secondary bituminization characteristic of vitrinite in good coking coals. Ash yields range from 8 to 52%, with composite seam averages of 15, 14 and 24%. Rare visible pyrite is in veinlets or small nodules; framboids and dispersed pyrite are absent. In borehole GDH-40 near Barapukuria (200-500 m depth), the mean random reflectance of vitrinite "A" ranges from 0.60 to 0.80% Ro and vitrinite "B" ranges from 0.55 to 0.65%. In borehole GDH-45 near Khalaspir (287-442 m), the reflectance of vitrinite ranges from 0.79 to 0.94%. In individual cases, the vitrinite is difficult to define because of semivitrinite at higher reflectance (forming a separate peak on several reflectograms) and because of surface bitumen films or resinous (?) inclusions at lower reflectance. On the basis of vitrinite reflectance, the coals can be considered to have entered the "main phase of bitumen generation" of organic thermal maturation as understood in petroleum geochemistry. ?? 1991.

Assessment of pore pressures and specific storage within sedimentary strata overlying underground mines

NASA Astrophysics Data System (ADS)

Timms, W.; David, K.; Barbour, L. S.

2016-12-01

Realistic values of specific storage (Ss) for groundwater systems are important to determine the spatial extent and timing of c pore pressure changes when the groundwater system is stressed. However, numerical groundwater models of underground excavations typically assume constant literature values of Ss. One part of our research program utilised high frequency pore pressure data to evaluate variability and changes in Ss within sedimentary strata overlying a longwall coal mine. Pore pressure data from a vertical series of 6 vibrating wire piezometers (50 to 278 m depth) recording at hourly intervals were compared with barometric pressure data over a period of several years, including data before and during mining. The site was located near the centre of a longwall panel that extracted 3 m of coal at a depth of 330 m. The data was processed to calculate loading efficiency and Ss values by multi-method analyses of barometric and earth tide responses. In situ Ss results varied over one to two orders of magnitude and indicated that Ss changed before and after excavation of underlying coal seams. The vertical leakage of groundwater within the constrained zone ( 10 to 150 m depth) was found to be limited, although some degree of vertical hydraulic connectivity was observed. Depressurization was evident in the fractured zone directly overlying the coal seam, and Ss changes at 250 m depth indicated this confined aquifer may have become unconfined. Our results demonstrate that high frequency pore pressure data can provide realistic Ss values. In situ Ss values were an order of magnitude lower than Ss measured by geomechnical tests of cores, and were significantly different to textbook values set in most local groundwater models. The timing and extent of groundwater level drawdown predicted by models may therefore be underestimated. We have shown, for the first time, that variability of Ss can be significant, and that these changes can provide important insights into how shallow and deep groundwater systems respond to underground mining.

Detection of smoldering combustion of coal with an odor meter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Edwards, J.C.

1995-05-01

A commercially available odor meter was evaluated as a detector of smoldering coal combustion, and compared with incipient carbon monoxide (CO) and hydrogen sulfide (H{sub 2}S) detection and a commercially available ionization-type smoke detector. Ten smoldering coal combustion experiments were conducted. For eight of the experiments, Pittsburgh seam coal with an average particle diameter of approximately 5 cm was heated by embedded electrical strip heaters. For two of the experiments mine size Pittsburgh seam coal was heated. Heating rates of 0.5, 0.8, and 1.1. kw were selected to provide experimental conditions characteristic of very slow and moderately fast heating formore » coal sample mass between 3 and 10 kg. It was found that the odor meter and smoke detector alarm had a good correlation, with the odor meter alarm occurring prior to the smoke alarm in four of the ten experiments. The odor meter gave an increase in its output signal above ambient equivalent to detecting 1 ppm of H{sub 2}S (ten times the odor threshold of H{sub 2}S) as an alarm value. This observed odor meter response occurred prior to the electrochemical detection of H{sub 2}S for five of the six experiments for which it was evaluated. In all six experiments for which the smoke optical density was evaluated, it was less than 0.023 m{sup -1} prior to the odor meter reaching alarm. In each of the eight experiments with 5 cm diameter coal particles the CO exceeded 5 ppm at odor meter alarm, while for the two experiments with mine size coal the CO was less than 3 ppm at odor meter alarm. The odor meter, as tested, is not a significant improvement over smoke and CO detectors. Because the odor meter responds to a variety of chemical compounds, with suitable modification and increased sensitivity it may be useful for detection of mine fires and thereby enhance mine safety.« less

The determination of methane resources from liquidated coal mines

NASA Astrophysics Data System (ADS)

Trenczek, Stanisław

2017-11-01

The article refers to methane presented in hard coal seams, which may pose a serious risk to workers, as evidenced by examples of incidents, and may also be a high energy source. That second issue concerns the possibility of obtaining methane from liquidated coal mines. There is discussed the current methodology for determination of methane resources from hard coal deposits. Methods of assessing methane emissions from hard coal deposits are given, including the degree of rock mass fracture, which is affected and not affected by mining. Additional criteria for methane recovery from the methane deposit are discussed by one example (of many types) of methane power generation equipment in the context of the estimation of potential viable resources. Finally, the concept of “methane resource exploitation from coal mine” refers to the potential for exploitation of the resource and the acquisition of methane for business purposes.

Control technique of spontaneous combustion in fully mechan ized stope during period of end caving under complex mining influence

NASA Astrophysics Data System (ADS)

Yuan, Benqing

2018-01-01

In view of the phenomenon of spontaneous combustion of coal seam occurring during the period of end caving under complex mining conditions, taking the 1116 (3) stope of Guqiao mine as the object of study, the causes of spontaneous combustion during the period of end caving are analyzed, according to the specific geological conditions of the stope to develop corresponding fire prevention measures, including the reduction of air supply and air leakage in goaf, reduce the amount of coal left, reasonable drainage, nitrogen injection for spontaneous combustion prevention, grouting for spontaneous combustion prevention and permanent closure, fundamentally eliminates the potential for spontaneous combustion during the period of 1116(3) stope end caving. The engineering practice shows that this kind of measure has reference value for the prevention and control of spontaneous combustion during the period of stope end caving.

Optimised layout and roadway support planning with integrated intelligent software

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kouniali, S.; Josien, J.P.; Piguet, J.P.

1996-12-01

Experience with knowledge-based systems for Layout planning and roadway support dimensioning is on hand in European coal mining since 1985. The systems SOUT (Support choice and dimensioning, 1989), SOUT 2, PLANANK (planning of bolt-support), Exos (layout planning diagnosis. 1994), Sout 3 (1995) have been developed in close cooperation by CdF{sup 1}. INERIS{sup 2} , EMN{sup 3} (France) and RAG{sup 4}, DMT{sup 5}, TH - Aachen{sup 6} (Germany); ISLSP (Integrated Software for Layout and support planning) development is in progress (completion scheduled for July 1996). This new software technology in combination with conventional programming systems, numerical models and existing databases turnedmore » out to be suited for setting-up an intelligent decision aid for layout and roadway support planning. The system enhances reliability of planning and optimises the safety-to-cost ratio for (1) deformation forecast for roadways in seam and surrounding rocks, consideration of the general position of the roadway in the rock mass (zones of increased pressure, position of operating and mined panels); (2) support dimensioning; (3) yielding arches, rigid arches, porch sets, rigid rings, yielding rings and bolting/shotcreting for drifts; (4) yielding arches, rigid arches and porch sets for roadways in seam; and (5) bolt support for gateroads (assessment of exclusion criteria and calculation of the bolting pattern) bolting of face-end zones (feasibility and safety assessment; stability guarantee).« less

Coal companies invest in more longwall capacity

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fiscor, S.

2006-02-15

This year's annual survey shows not much has changed since last year. The overall population stands at 47 mines operating 53 longwalls. CONSOL Energy remains the leading US longwall operator with 13 installations, followed by Arch Coal (5), Robert E. Murray (5) and Massey Energy (4). West Virginia remains the leading longwall mining state with 14 faces in 2005, followed by Pennsylvania (8), Alabama (7), Utah (7) and Colorado (5). A detailed table gives for each longwall installation, the ownership, seam height, cutting height, panel width and length, overburden, number of gate entries, depth of cut, model of equipment usedmore » (shearer, haulage system, roof support, face conveyor, stage loader, crusher, electrical controls and voltage to face). 1 photos., 2 tabs.« less

Evaluation of Rare Earth Element Extraction from North Dakota Coal-Related Feed Stocks

NASA Astrophysics Data System (ADS)

Laudal, Daniel A.

The rare earth elements consist of the lanthanide series of elements with atomic numbers from 57-71 and also include yttrium and scandium. Due to their unique properties, rare earth elements are crucial materials in an incredible array of consumer goods, energy system components and military defense applications. However, the global production and entire value chain for rare earth elements is dominated by China, with the U.S. currently 100% import reliant for these critical materials. Traditional mineral ores including previously mined deposits in the U.S., however, have several challenges. Chief among these is that the content of the most critical and valuable of the rare earths are deficient, making mining uneconomical. Further, the supply of these most critical rare earths is nearly 100% produced in China from a single resource that is only projected to last another 10 to 20 years. The U.S. currently considers the rare earths market an issue of national security. It is imperative that alternative domestic sources of rare earths be identified and methods developed to produce them. Recently, coal and coal byproducts have been identified as one of these promising alternative resources. This dissertation details a study on evaluation of the technical and economic feasibility of rare earth element recovery from North Dakota lignite coal and lignite-related feedstocks. There were four major goals of this study: i) identify lignite or lignite-related feedstocks with total rare earth element content above 300 parts per million, a threshold dictated by the agency who funded this research as the minimum for economic viability, ii) determine the geochemistry of the feedstocks and understand the forms and modes of occurrence of the rare earth elements, information necessary to inform the development of extraction and concentration methods, iii) identify processing methods to concentrate the rare earth elements from the feedstocks to a target of two weight percent, a value that would be sufficient to leverage existing separation and refining methods developed for the traditional mineral ore industry, and iv) develop a process that is economically viable and environmentally benign. To achieve these overall goals, and to prove or disprove the research hypotheses, the research scope was broken down into three main efforts: i) sampling and characterization of potential feedstocks, ii) laboratory-scale development and testing of rare earth element extraction and concentration methods, and iii) process design and technical and economic feasibility evaluation. In total, 174 unique samples were collected, and several locations were identified that exceeded the 300 ppm total rare earth elements target. The results showed that on a whole sample basis, the rare earths are most concentrated in the clay-rich sediments associated with the coal seams, but on an ash basis in certain locations within certain coal seams the content is significantly higher, an unexpected finding given prior research. At Falkirk Mine near Underwood, North Dakota three coal seams were found to have elevated levels of rare earths, ranging from about 300 to 600 ppm on an ash basis. Additionally, exceptionally high rare earths content was found in samples collected from an outcropping of the Harmon-Hansen coal zone in southwestern North Dakota that contained 2300 ppm on an ash basis. The results dictated that extraction and concentration methods be developed for these rare earth element-rich coals, instead of the mineral-rich sediments. This effort also found that at a commercial-scale, due to non-uniformity of the rare earths content stratigraphically in the coal seams, selective mining practices will be needed to target specific locations within the seams. The bulk mining and blending practices as Falkirk Mine result in a relatively low total rare earths content in the feed coal entering the Coal Creek Power Station adjacent to the mine. Characterization of the coal samples identified that the predominant modes of rare earths occurrence in the lignite coals are associations with the organic matter, primarily as coordination complexes and a lesser amount as ion-exchangeable cations on oxygen functional groups. Overall it appears that about 80-95% of rare earths content in North Dakota lignite is organically associated, and not present in mineral forms, which due to the weak organic bonding, presented a unique opportunity for extraction. The process developed for extraction of rare earths was applied to the raw lignite coals instead of fly ash or other byproducts being investigated extensively in the literature. Rather, the process uses a dilute acid leaching process to strip the organically associated rare earths from the lignite with very high efficiency of about 70-90% at equilibrium contact times. Although the extraction kinetics are quite fast given commercial leaching operations, there is some tradeoff between extraction efficiency and contact time. (Abstract shortened by ProQuest.).

Horizontal EDNA miner

DOE Office of Scientific and Technical Information (OSTI.GOV)

Justice, J.C.; Delli-Gatti, F.A.

1985-12-03

A mining machine is utilized for making original generally horizontal bores in coal seams, and for enlarging preexisting bores. A single cutting head is mounted for rotation about a first horizontal axis generally perpendicular to the dimension of elongation of the horizontal bore, and is pivotal about a second horizontal axis, parallel to the first axis, to change its cutting, vertical position within the bore. A non-rotatable body member, with side wall supports, is mounted posteriorly of the cutting head, and includes a conveyor mechanism and a power mechanism operatively connected to it. The machine can be sumped into amore » bore and then the cutting head rotated about the second axis to change the vertical position thereof, and then moved rearwardly, any cut material being continuously conveyed to the bore mouth by the conveyor mechanism. The amount of vertical movement during the pivoting action about the second axis is controlled in response to the automatic sensing of the thickness of the coal seam in which the machine operates.« less

Managing produced water from coal seam gas projects: implications for an emerging industry in Australia.

PubMed

Davies, Peter J; Gore, Damian B; Khan, Stuart J

2015-07-01

This paper reviews the environmental problems, impacts and risks associated with the generation and disposal of produced water by the emerging coal seam gas (CSG) industry and how it may be relevant to Australia and similar physical settings. With only limited independent research on the potential environmental impacts of produced water, is it necessary for industry and government policy makers and regulators to draw upon the experiences of related endeavours such as mining and groundwater extraction accepting that the conclusions may not always be directly transferrable. CSG is widely touted in Australia as having the potential to provide significant economic and energy security benefits, yet the environmental and health policies and the planning and regulatory setting are yet to mature and are continuing to evolve amidst ongoing social and environmental concerns and political indecision. In this review, produced water has been defined as water that is brought to the land surface during the process of recovering methane gas from coal seams and includes water sourced from CSG wells as well as flowback water associated with drilling, hydraulic fracturing and gas extraction. A brief overview of produced water generation, its characteristics and environmental issues is provided. A review of past lessons and identification of potential risks, including disposal options, is included to assist in planning and management of this industry.

Effects of strong mining tremors, and assessment of the buildings' resistance to the dynamic impacts

NASA Astrophysics Data System (ADS)

Bryt-Nitarska, Izabela

2018-04-01

A particularly important element in the assessment of the actual state of the threats which is caused by conducting the mining exploitation of seams bumping under the urban areas is to diagnose the condition of the land development after hard shocks. In the buildings, for which the impact of the mining activities, including the tremors, is not taken into account at the stage of design and formulation of the strength and use conditions, conclusions from the structure behaviour under the tremor influence are an essential part of the assessment of the possibility for transferring the further dynamic impacts. The use of conclusions from the in situ research has its role in anticipating the behaviour of the buildings in case of the forecast of the mining tremors effects in the regions of their impacts. These conclusions should also provide ground for the assumptions to the scope of the building prevention necessary to be taken in case of forecasting the tremors with big intensity. Based on the analysis of effects which occurred in the land development after the highenergy mining tremors, the elements of the dynamic resistance assessment for the buildings with traditional structure were discussed.

The exploration and prevention of mine water invasion in Feicheng area based on RS

NASA Astrophysics Data System (ADS)

Zheng, Yong-Guo; Wang, Ping; Ting, He

2004-10-01

Recently, when the ninth and tenth were mined in Feiching city mining area, several mine wells occurred on water invasion. Based on systematic interpretation of TMimages in Fei Cheng mining area, authors find that there are five zones of NS trending lineaments, which nearly distribute in radial in TM images. Image processing can be divided into three types, they are spectrum enhancement, spatial filtering and data fusion, the useful methods in this area are auto-adaptive enhancement, density slicing and K-L transform. With ninth and tenth seam coals mined, three mines of east area have broken out serious accidents of water. Statistical materials and the test of water quality drawing off five limestone indicates water-yielding zone near NS, NNE, and NW trending faults, or near intersection point of its and others. In order to solve the problem, using remote sensing and other techniques, we try to find some influential factors on mine flow. Further analyses, such as, the exploration of geology on earth, and microcosmic from rock slice, the authors find that there are some reasons which lead to water invasion such as geological structure, karsts, index and so on, in which the main reason might be north-south deep fracture which is the pathway of well water's distribution, migration and recharge of mine water. There being more complicate geologic structure in the west of mine area, at last, with RS authors point out important zone of mine water invasion which the prevention-control of hazards from mine water and some measures to avoid water blast in future.

Regional price targets appropriate for advanced coal extraction

NASA Technical Reports Server (NTRS)

Terasawa, K. L.; Whipple, D. M.

1980-01-01

A methodology is presented for predicting coal prices in regional markets for the target time frames 1985 and 2000 that could subsequently be used to guide the development of an advanced coal extraction system. The model constructed is a supply and demand model that focuses on underground mining since the advanced technology is expected to be developed for these reserves by the target years. Coal reserve data and the cost of operating a mine are used to obtain the minimum acceptable selling price that would induce the producer to bring the mine into production. Based on this information, market supply curves can be generated. Demand by region is calculated based on an EEA methodology that emphasizes demand by electric utilities and demand by industry. The demand and supply curves are then used to obtain the price targets. The results show a growth in the size of the markets for compliance and low sulphur coal regions. A significant rise in the real price of coal is not expected even by the year 2000. The model predicts heavy reliance on mines with thick seams, larger block size and deep overburden.

Ground-water hydrology and quality before and after strip mining of a small watershed in Jefferson County, Ohio

USGS Publications Warehouse

Razem, A.C.

1984-01-01

Ground-water conditions before and after surface mining of a small watershed are described as part of a study to determine the effects of mining on hydrologic systems. The watershed was underlain by stratified sedimentary rocks containing local aquifers above shaley clay beds associated with the major coal seams. Mining involved removing the overburden rocks, including most of the top aquifer, stripping the coal, and recontouring the overburden spoils to the approximate premining shape of the watershed. Replacement of the top aquifer by spoils during regrading has caused many changes in recharge and discharge rates, saturated thickness, aquifer characteristics, and water quality. In the middle aquifer there were changes in saturated thickness and water quality. Resaturation of the top-aquifer spoils during and after reclamation has been slow. Saturated thicknesses have ranged from zero initially after mining to 4 feet after 1 1/2 years. Water levels in the middle aquifer have risen from a few feet to 40 feet. Water quality generally has been degraded: concentrations of bicarbonate, calcium, magnesium , chloride, iron, manganese, sulfate, and dissolved solids have increased. Premining water types remained about the same after mining, except for some changes from bicarbonate type to sulfate type. (USGS)

The Effects of Mountaintop Mines and Valley Fills on Aquatic ...

EPA Pesticide Factsheets

This report assesses the state of the science on the environmental impacts of mountaintop mines and valley fills (MTM-VF) on streams in the Central Appalachian Coalfields. Our review focused on the aquatic impacts of mountaintop removal coal mining, which, as its name suggests, involves removing all or some portion of the top of a mountain or ridge to expose and mine one or more coal seams. The excess overburden is disposed of in constructed fills in small valleys or hollows adjacent to the mining site. MTM-VF lead directly to five principal alterations of stream ecosystems: (1) springs, intermittent streams, and small perennial streams are permanently lost with the removal of the mountain and from burial under fill, (2) concentrations of major chemical ions are persistently elevated downstream, (3) degraded water quality reaches levels that are acutely lethal to standard laboratory test organisms, (4) selenium concentrations are elevated, reaching concentrations that have caused toxic effects in fish and birds and (5) macroinvertebrate and fish communities are consistently and significantly degraded. This report assesses the state of the science on the environmental impacts of Mountaintop Mines and Valley Fills (MTM-VF) on streams in the Central Appalachian Coalfields. The draft report will be externally peer reviewed by EPA's Science Advisory Board in early 2010.

Novel ultra-wideband (UWB) photonic generation through photodetection and cross-absorption modulation in a single electroabsorption modulator.

PubMed

Wu, Tsu-Hsiu; Wu, Jui-pin; Chiu, Yi-Jen

2010-02-15

We propose and demonstrate, by proof of concept, a novel method of ultra-wide band (UWB) photonic generation using photodetection and cross-absorption modulation (XAM) of multiple quantum wells (MQW) in a single short-terminated electroabsorption modulator (SEAM). As an optical pump pulse excite the MQWs of SEAM waveguide, the probe light pulse with the same polarity can be generated through XAM, simultaneously creating photocurrent pulse propagating along the waveguide. Using the short termination of SEAM accompanied by the delayed microwave line, the photocurrent pulse can be reversed in polarity and re-modulated the waveguide, forming a monocycle UWB optical pulse. An 89 ps cycle of monocycle pulse with 114% fractional bandwidth is obtained, where the electrical power spectrum centered at 4 GHz of frequency ranges from 0.1 GHz to 8 GHz for -10 dB drops. Meanwhile, the generation processing is also confirmed by observing the same cycle of monocycle electrical pulse from the photodetection of SEAM. The whole optical processing is performed inside a compact semiconductor device, suggesting the optoelectronic integration template has a potential for the application of UWB photonic generation.

Predicting ground-water movement in large mine spoil areas in the Appalachian Plateau

USGS Publications Warehouse

Wunsch, D.R.; Dinger, J.S.; Graham, C.D.R.

1999-01-01

Spoil created by surface mining can accumulate large quantities of ground-water, which can create geotechnical or regulatory problems, as well as flood active mine pits. A current study at a large (4.1 km2), thick, (up to 90 m) spoil body in eastern Kentucky reveals important factors that control the storage and movement of water. Ground-water recharge occurs along the periphery of the spoil body where surface-water drainage is blocked, as well as from infiltration along the spoil-bedrock contact, recharge from adjacent bedrock, and to a minor extent, through macropores at the spoil's surface. Based on an average saturated thickness of 6.4 m for all spoil wells, and assuming an estimated porosity of 20%, approximately 5.2 x 106 m3 of water is stored within the existing 4.1 km2 of reclaimed spoil. A conceptual model of ground-water flow, based on data from monitoring wells, dye-tracing data, discharge from springs and ponds, hydraulic gradients, chemical data, field reconnaissance, and aerial photographs indicate that three distinct but interconnected saturated zones have been established: one in the spoil's interior, and others in the valley fills that surround the main spoil body at lower elevations. Ground-water movement is sluggish in the spoil's interior, but moves quickly through the valley fills. The conceptual model shows that a prediction of ground-water occurrence, movement, and quality can be made for active or abandoned spoil areas if all or some of the following data are available: structural contour of the base of the lowest coal seam being mined, pre-mining topography, documentation of mining methods employed throughout the mine, overburden characteristics, and aerial photographs of mine progression.Spoil created by surface mining can accumulate large quantities of ground-water, which can create geotechnical or regulatory problems, as well as flood active mine pits. A current study at a large (4.1 km2), thick, (up to 90 m) spoil body in eastern Kentucky reveals important factors that control the storage and movement of water. Ground-water recharge occurs along the periphery of the spoil body where surface-water drainage is blocked, as well as from infiltration along the spoil-bedrock contact, recharge from adjacent bedrock, and to a minor extent, through macropores at the spoil's surface. Based on an average saturated thickness of 6.4 m for all spoil wells, and assuming an estimated porosity of 20%, approximately 5.2 ?? 106 m3 of water is stored within the existing 4.1 km2 of reclaimed spoil. A conceptual model of ground-water flow, based on data from monitoring wells, dye-tracing data, discharge from springs and ponds, hydraulic gradients, chemical data, field reconnaissance, and aerial photographs indicate that three distinct but interconnected saturated zones have been established: one in the spoil's interior, and others in the valley fills that surround the main spoil body at lower elevations. Ground-water movement is sluggish in the spoil's interior, but moves quickly through the valley fills. The conceptual model shows that a prediction of ground-water occurrence, movement, and quality can be made for active or abandoned spoil areas if all or some of the following data are available: structural contour of the base of the lowest coal seam being mined, pre-mining topography, documentation of mining methods employed throughout the mine, overburden characteristics, and aerial photographs of mine progression.

What happened to the TSM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brezovec, D.

1983-11-01

A new coal mining machine that was going to pull some 40 million tons of coal from the Appalachian coalfields by 1986 has had more than its share of start-up problems. The machine, known as the Thin Seam Miner (TSM), is a $2.7-million auger-type mining machine that is designed to bore 220 ft into new or abandoned highwalls (CA 5/82 p. 106). Gamma-ray sensors located near the continuous drum miner-type cutter head monitor for rock and other sensors monitor for methane. The machines are designed to produce about 425 tons per shift from a 36-in.-thick coal seam. The machines weremore » introduced officially to the American coal industry at a luncheon Aug. 19, 1981, in a ballroom at the Lexington, Ky., Hyatt Regency Hotel. At the luncheon, some 200 coal industry executives and others sipped champagne and listened to glowing reports of how 24 of the machines would produce 2.2 million tons of coal by the end of 1981 and 64 of the machines would produce 6.6 million tons by the end of 1982. The machines would be built in Holland by RijnSchelde-Verolme (RSV), a major Dutch shipbuilder, and managed in the United States by Advanced Coal Management (ACM), a company formed for the purpose by James D. Stacy, a colorful, cigar-smoking stock car owner whose experience in the coal business dated from only the mid-1970s.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kirhan, S.; Inaner, H.; Nakoman, E.

This study focuses on some lignite properties and calculation of lignite reserves with two classical (isopach and polygon) methods in the Aydin-Sahinali field, Turkey, which is located in the western Turkey. This field has been mined by a private coal company since 1960 by open-cast and mainly underground mining methods. The producing lignites are consumed in domestic heating and industrial factories around Aydin. The metamorphic rocks of Palaezoic age form the basement of the coal field. The lignite-bearing unit of Miocene age, from bottom to the top, consists mainly of pebblestone, lignite and clayey lignite, siltstone with sandstone lenses, whitemore » colored claystone, clayey limestone and silisified limestone lenses. This unit in the lignite field was unconformably overlain by Pliocene unconsolidated sands and gravels. Three hundred seventy-three borehole data have been evaluated, and this study shows that a relatively thick and lateral extensive lignite seam has a mineable thickness of 1.6-14.4 m. The core samples from boreholes in panels in the lignite field indicate that the coal seam, on an as-received basis, contains high moisture contents (17.95-23.45%, average), high ash yields (16.30-26.03%, average), relatively high net calorific values (3,281-3,854 kcal/kg, average), and low total sulfur contents (1.00-1.22%, average). The remaining lignite potential in the Aydin-Sahinali lignite field was calculated as a 4.7 Mt of measured and a 2.9 Mt of mineable lignite-reserves.« less

The Effects of Mountaintop Mines and Valley Fills on Aquatic ...

EPA Pesticide Factsheets

EPA announced the availability of the final report, The Effects of Mountaintop Mines and Valley Fills on Aquatic Ecosystems of the Central Appalachian Coalfields. This report assesses the state of the science on the environmental impacts of mountaintop mines and valley fills (MTM-VF) on streams in the central Appalachian coalfields. These coalfields cover about 48,000 square kilometers (122 million acres) in West Virginia, Kentucky, Virginia and Tennessee, USA. Our reviews focused on the impacts on mountaintop removal coal mining, which as its name suggests, involves removing all or some portion of the top of a mountain or ridge to expose and mine one or more coal seams. The excess overburden is disposed of in constructed fills in small valleys or hollows adjacent to the mining site. Our conclusions, based on evidence from the peer-reviewed literature and from the U.S. Environmental Protection Agency's Programmatic Environmental Impact Statement released in 2005, are that mountaintop mines and valley fills lead directly to five principal alterations of stream ecosystems: springs and ephemeral, intermittent and perennial streams are permanently lost with the removal of the mountain and from burial under fill, concentrations of major chemical ions are persistently elevated downstream, degraded water quality reaches levels that are acutely lethal to organisms in standard aquatic toxicity tests, selenium concentrations are elevated, reaching concentrations t

Development of technical means for directional hydraulic fracturing with shearing loading of borehole walls

NASA Astrophysics Data System (ADS)

Rybalkin, LA; Patutin, AV; Patutin, DV

2018-03-01

During the process of mineral deposits’ mining one of the most important conditions for safe and economically profitable work of a mining enterprise is obtaining timely information on the stress state of the developed massif. One of the most common methods of remote study of the geomechanical state of the rock massif is hydraulic fracturing of the formation. Directional hydraulic fracturing is a type of the method employed to form cracks across production wells. This technology was most widely used in the gas industry to extract gas from shale formations. In mining, this technology is used to set up filtration screens, to integrate degassing, to soften the hard roof of coal seams. Possible practical appliance is the expansion of the application field of this technology to intensify the production of viscous oil, to leach non-ferrous metals, to create in the rock massif anti-filtration screens for various purposes, as well as to measure stresses acting along the wells.

Rock burst governance of working face under igneous rock

NASA Astrophysics Data System (ADS)

Chang, Zhenxing; Yu, Yue

2017-01-01

As a typical failure phenomenon, rock burst occurs in many mines. It can not only cause the working face to cease production, but also cause serious damage to production equipment, and even result in casualties. To explore how to govern rock burst of working face under igneous rock, the 10416 working face in some mine is taken as engineering background. The supports damaged extensively and rock burst took place when the working face advanced. This paper establishes the mechanical model and conducts theoretical analysis and calculation to predict the fracture and migration mechanism and energy release of the thick hard igneous rock above the working face, and to obtain the advancing distance of the working face when the igneous rock fractures and critical value of the energy when rock burst occurs. Based on the specific conditions of the mine, this paper put forward three kinds of governance measures, which are borehole pressure relief, coal seam water injection and blasting pressure relief.

Example Building Damage Caused by Mining Exploitation in Disturbed Rock Mass

NASA Astrophysics Data System (ADS)

Florkowska, Lucyna

2013-06-01

Issues concerning protection of buildings against the impact of underground coal mining pose significant scientific and engineering challenges. In Poland, where mining is a potent and prominent industry assuring domestic energy security, regions within reach of mining influences are plenty. Moreover, due to their industrial character they are also densely built-up areas. Because minerals have been extracted on an industrial scale in majority of those areas for many years, the rock mass structure has been significantly disturbed. Hence, exploitation of successive layers of multi-seam deposits might cause considerable damage - both in terms of surface and existing infrastructure networks. In the light of those facts, the means of mining and building prevention have to be improved on a regular basis. Moreover, they have to be underpinned by reliable analyses holistically capturing the comprehensive picture of the mining, geotechnical and constructional situation of structures. Scientific research conducted based on observations and measurements of mining-induced strain in buildings is deployed to do just that. Presented in this paper examples of damage sustained by buildings armed with protection against mining influences give an account of impact the mining exploitation in disturbed rock mass can have. This paper is based on analyses of mining damage to church and Nursing Home owned by Evangelical Augsburg Parish in Bytom-Miechowice. Neighbouring buildings differ in the date they were built, construction, building technology, geometry of the building body and fitted protection against mining damage. Both the buildings, however, have sustained lately significant deformation and damage caused by repeated mining exploitation. Selected damage has been discussed hereunder. The structures have been characterised, their current situation and mining history have been outlined, which have taken their toll on character and magnitude of damage. Description has been supplemented with photographic documentation.

Lateral variation in geochemistry, petrology, and palynology in the Elswick coal bed, Pike County, Kentucky

USGS Publications Warehouse

Hower, J.C.; Ruppert, L.F.; Eble, C.F.

2007-01-01

The Middle Pennsylvanian/Langsettian (Westphalian A) Elswick coal bed, correlative to the Upper Banner of Virginia, is a rare example of a mined high-sulfur (> 2%) coal in Eastern Kentucky, a region known for low-sulfur coals. To characterize lateral variation in the geochemistry, petrography, and palynology of the Elswick coal bed, three sites were sampled along a southeast-northwest transect within a single mine. At the southeastern site, the lower 101??cm of the 116-cm thick coal is dull, generally dominated by durain and dull clarain. While all benches at this site fit within the previously-defined "mixed palynoflora - moderate/low vitrinite group," suggesting a stressed environment of deposition, the palynology of the benches of the dull interval show greater diversity than might be expected just from the petrology. Lithology is generally similar between the sites, but each site has some differences in the petrology. Overall, the coal bed shows significant lateral variation in properties at the mine scale, some of which can be attributed to the gain or loss of upper and lower lithologies, either through an actual physical merging or through the change in character of lithotypes. Sulfur content varies between the three sites examined for this study. Site 3, located in the northwestern portion of the study area is characterized by a strikingly high sulfur zone (7.45%) in the middle of the coal bed, a feature missing at the other sites. Pyrite and marcasite, in a mid-seam lithotype at the northwestern site (site 3), show signs of overgrowths, indicating multiple generations of sulfide emplacement. The high-sulfur site 3 lithologies all have massive overgrowths of euhedral and framboidal pyrite, fracture- and cleat-fill pyrite, and sulfide emplacement in fusinite lumens. Sulfur is high throughout the mine area, but variations are evident in the extent of secondary growth of sulfides. ?? 2006 Elsevier B.V. All rights reserved.

Love-type seam-waves in washout models of coal seams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Breitzke, M.; Dresen, L.

The propagation of Love seam-waves across washouts of coal seams was studied by calculating synthetic seismograms with a finite-difference method. Seam interruption, seam end and seam thinning models ere investigated. The horizontal offset, the dip of the discontinuities and the degree of erosion served as variable parameters. Maximum displacement amplitudes, relative spectral amplitudes and phase and group slowness curves were extracted from the synthetic seismograms. Both seam interruption and seam thinning reduce the maximum displacement amplitudes of the transmitted Love seam-waves. The degree of amplitude reduction depends on the horizontal offset and the degree of erosion. It is four timesmore » greater for a total seam interruption than for an equivalent seam thinning with a horizontal offset of four times the seam thickness. In a seam cut vertically, the impedance contrast between the coal and the washout filling determines the maximum displacement amplitudes of the reflected Love seam-waves. They diminish by a maximum factor of four in oblique interruption zone discontinuities with a dip of maximum 27/sup 0/, and by a maximum factor of ten in a seam thinning with a degree of erosion of at least 22%.« less

Production history matching to determine reservoir properties of important coal groups in the Upper Pottsville formation, Brookwood and Oak Grove fields, Black Warrior Basin, Alabama

PubMed Central

Karacan, C. Özgen

2015-01-01

The Black Warrior Basin of Alabama is one of the most important coal mining and coalbed methane production areas in the United States. Methane control efforts through degasification that started almost 25 years ago for the sole purpose of ensuring mining safety resulted in more than 5000 coalbed methane wells distributed within various fields throughout the basin. The wells are completed mostly in the Pratt, Mary Lee, and Black Creek coal groups of the Upper Pottsville formation and present a unique opportunity to understand methane reservoir properties of these coals and to improve their degasification performances. The Brookwood and Oak Grove fields in the Black Warrior Basin are probably two of the most important fields in the basin due to current longwall coal mining activities. In this work, methane and water productions of 92 vertical wellbores drilled, some completed 20 years ago, over a current large coal mine district located in these two fields, were analyzed by history matching techniques. The boreholes were completed at the Mary Lee coal group, or at combinations of the Pratt, Mary Lee, and Black Creek groups. History matching models were prepared and performed according to properties of each coal group. Decline curve analyses showed that effective exponential decline rates of the wells were between 2% and 25% per year. Results of production history matching showed, although they varied by coal group, that pressure decreased as much as 80% to nearly 25 psi in some areas and resulted in corresponding decreases in methane content. Water saturation in coals decreased from 100% to between 20 and 80%, improving gas relative permeabilities to as much as 0.8. As a result of primary depletion, permeability of coal seams increased between 10 and 40% compared to their original permeability, which varied between 1 and 10 md depending on depth and coal seam. These results not only can be used for diagnostic and interpretation purposes, but can be used as parameter distributions in probabilistic simulations, as illustrated in the last section of this paper. They can also be used in conjunction with spatial modeling and geological considerations to calculate potential methane emissions in operating mines. PMID:26191096

Methane emissions and airflow patterns on a longwall face: Potential influences from longwall gob permeability distributions on a bleederless longwall panel.

PubMed

Schatzel, S J; Krog, R B; Dougherty, H

2017-01-01

Longwall face ventilation is an important component of the overall coal mine ventilation system. Increased production rates due to higher-capacity mining equipment tend to also increase methane emission rates from the coal face, which must be diluted by the face ventilation. Increases in panel length, with some mines exceeding 6,100 m (20,000 ft), and panel width provide additional challenges to face ventilation designs. To assess the effectiveness of current face ventilation practices at a study site, a face monitoring study with continuous monitoring of methane concentrations and automated recording of longwall shearer activity was combined with a tracer gas test on a longwall face. The study was conducted at a U.S. longwall mine operating in a thick, bituminous coal seam and using a U-type, bleederless ventilation system. Multiple gob gas ventholes were located near the longwall face. These boreholes had some unusual design concepts, including a system of manifolds to modify borehole vacuum and flow and completion depths close to the horizon of the mined coalbed that enabled direct communication with the mine atmosphere. The mine operator also had the capacity to inject nitrogen into the longwall gob, which occurred during the monitoring study. The results show that emission rates on the longwall face showed a very limited increase in methane concentrations from headgate to tailgate despite the occurrence of methane delays during monitoring. Average face air velocities were 3.03 m/s (596 fpm) at shield 57 and 2.20 m/s (433 fpm) at shield 165. The time required for the sulfur hexafluoride (SF 6 ) peak to occur at each monitoring location has been interpreted as being representative of the movement of the tracer slug. The rate of movement of the slug was much slower in reaching the first monitoring location at shield 57 compared with the other face locations. This lower rate of movement, compared with the main face ventilation, is thought to be the product of a flow path within and behind the shields that is moving in the general direction of the headgate to the tailgate. Barometric pressure variations were pronounced over the course of the study and varied on a diurnal basis.

Long-term effects of surface coal mining on ground-water levels and quality in two small watersheds in eastern Ohio

USGS Publications Warehouse

Cunningham, W.L.; Jones, R.L.

1990-01-01

Two small watersheds in eastern Ohio that were surface mined for coal and reclaimed were studied during 1986-89. Water-level and water-quality data were compared with similar data collected during previous investigations conducted during 1976-83 to determine long-term effects of surface mining on the hydrologic system. Before mining, the watersheds were characterized by sequences of flat-lying sedimentary rocks containing two major coal seams and underclays. An aquifer was present above each of the underclays. Surface mining removed the upper aquifer, stripped the coal seam, and replaced the sediment. This created a new upper aquifer with different hydraulic and chemical characteristics. Mining did not disturb the middle aquifer. A third, deeper aquifer in each watershed was not studied. Water levels were continuously recorded in one well in each aquifer. Other wells were measured every 2 months. Water levels in the upper aquifers reached hydraulic equilibrium from 2 to 5 years after mining ceased. Water levels in the middle aquifers increased more than 5 feet during mining and reached equilibrium almost immediately thereafter. Water samples were collected from three upper-aquifer well, a seep from the upper aquifer, and the stream in each watershed. Two samples were collected in 1986 and 1987, and one each in 1988 and 1989. In both watersheds, sulfate replaced bicarbonate as the dominant upper-aquifer and surface-water anion after mining. For the upper aquifer of a watershed located in Muskingum County, water-quality data were grouped into premining and late postmining time periods (1986-89). The premining median pH and concentration of dissolved solids and sulfate were 7.6, 378 mg/L (milligrams per liter), and 41 mg/L, respectively. The premining median concentrations of iron and manganese were 10? /L (micrograms per liter) and 25?, respectively. The postmining median values of pH, dissolved solids, and sulfate were 6.7, 1,150 mg/L, and 560 mg/L, respectively. The postmining median concentrations of iron and manganese were 3,900?g/L and 1,900? g/L, respectively. For the upper aquifer of a watershed located in Jefferson County, the water-quality data were grouped into three time periods of premining, early postmining, and late postmining. The premining median pH and concentrations of dissolved solids and sulfate were 7.0, 335 mg/L, and 85 mg/L, respectively. The premining median concentrations of iron and manganese were 30? g/L for each constituent. Late postmining median pH and concentrations of dissolved solids and sulfate were 6.7, 1,495 mg/L, and 825 mg/L, respectively. The postmining median concentrations of iron and manganese were 31? g/L and 1,015? g/L, respectively. Chemistry of water in the middle aquifer in each watershed underwent similar changes. In general, statistically significant increases in concentrations of dissolved constituents occurred because of surface mining. In some constituents, concentrations increased by more than an order of magnitude. The continued decrease in pH indicated that ground water had no reached geochemical equilibrium in either watershed more than 8 years after mining.

Analysis of the current rib support practices and techniques in U.S. coal mines

PubMed Central

Mohamed, Khaled M.; Murphy, Michael M.; Lawson, Heather E.; Klemetti, Ted

2016-01-01

Design of rib support systems in U.S. coal mines is based primarily on local practices and experience. A better understanding of current rib support practices in U.S. coal mines is crucial for developing a sound engineering rib support design tool. The objective of this paper is to analyze the current practices of rib control in U.S. coal mines. Twenty underground coal mines were studied representing various coal basins, coal seams, geology, loading conditions, and rib control strategies. The key findings are: (1) any rib design guideline or tool should take into account external rib support as well as internal bolting; (2) rib bolts on their own cannot contain rib spall, especially in soft ribs subjected to significant load—external rib control devices such as mesh are required in such cases to contain rib sloughing; (3) the majority of the studied mines follow the overburden depth and entry height thresholds recommended by the Program Information Bulletin 11-29 issued by the Mine Safety and Health Administration; (4) potential rib instability occurred when certain geological features prevailed—these include draw slate and/or bone coal near the rib/roof line, claystone partings, and soft coal bench overlain by rock strata; (5) 47% of the studied rib spall was classified as blocky—this could indicate a high potential of rib hazards; and (6) rib injury rates of the studied mines for the last three years emphasize the need for more rib control management for mines operating at overburden depths between 152.4 m and 304.8 m. PMID:27648341

Dynamical correlation effects on photoisomerization: Ab initio multiple spawning dynamics with MS-CASPT2 for a model trans-protonated Schiff base

DOE PAGES

Liu, Lihong; Liu, Jian; Martinez, Todd J.

2015-12-17

Here, we investigate the photoisomerization of a model retinal protonated Schiff base (trans-PSB3) using ab initio multiple spawning (AIMS) based on multi-state second order perturbation theory (MSPT2). Discrepancies between the photodynamical mechanism computed with three-root state-averaged complete active space self-consistent field (SA-3-CASSCF, which does not include dynamic electron correlation effects) and MSPT2 show that dynamic correlation is critical in this photoisomerization reaction. Furthermore, we show that the photodynamics of trans-PSB3 is not well described by predictions based on minimum energy conical intersections (MECIs) or minimum energy conical intersection (CI) seam paths. Instead, most of the CIs involved in the photoisomerizationmore » are far from MECIs and minimum energy CI seam paths. Thus, both dynamical nuclear effects and dynamic electron correlation are critical to understanding the photochemical mechanism.« less

Use of Landsat thermal imagery for dynamically monitoring spontaneous combustion of Datong Jurassic coalfields in China

NASA Astrophysics Data System (ADS)

Xue, Yongan; Liu, Jin; Li, Jun; Shang, Changsheng; Zhao, Jinling; Zhang, Mingmei

2018-06-01

It is highly helpful and necessary to investigate and monitor the status of coal seam. Fortunately, remote sensing has facilitated the identification and dynamical monitoring of spontaneous combustion for a large area coal mining area, especially using the time series remotely-sensed datasets. In this paper, Datong Jurassic coal mining area is used as the study area, China, and an exclusion method and a multiple-factor analysis method are jointly used to identify the spontaneous combustion, including land surface temperature (LST), burnt rocks, and land use and land cover change (LUCC). The LST is firstly retrieved using a single-window algorithm due to a thermal infrared band of Landsat-5 TM (Thematic Mapper). Burnt rocks is then extracted using a decision-tree classification method based on a high-resolution SPOT-5 image. The thermal anomaly areas are identified and refined by the spatial overlay analysis of the above affecting factors. Three-period maps of coal fire areas are obtained and dynamically analyzed in 2007, 2009 and 2010. The results show that a total of 12 coal fire areas have been identified, which account for more than 1% of the total area of the study area. In general, there is an increasing trend yearly and a total of 771,970 m2 is increased. The average annual increase is 257,320 m2, the average annual growth rate is 3.78%, and the dynamic degree is 11.29%.

Simulation of Asymmetric Destabilization of Mine-void Rock Masses Using a Large 3D Physical Model

NASA Astrophysics Data System (ADS)

Lai, X. P.; Shan, P. F.; Cao, J. T.; Cui, F.; Sun, H.

2016-02-01

When mechanized sub-horizontal section top coal caving (SSTCC) is used as an underground mining method for exploiting extremely steep and thick coal seams (ESTCS), a large-scale surrounding rock caving may be violently created and have the potential to induce asymmetric destabilization from mine voids. In this study, a methodology for assessing the destabilization was developed to simulate the Weihuliang coal mine in the Urumchi coal field, China. Coal-rock mass and geological structure characterization were integrated with rock mechanics testing for assessment of the methodology and factors influencing asymmetric destabilization. The porous rock-like composite material ensured accuracy for building a 3D geological physical model of mechanized SSTCC by combining multi-mean timely track monitoring including acoustic emission, crack optical acquirement, roof separation observation, and close-field photogrammetry. An asymmetric 3D modeling analysis for destabilization characteristics was completed. Data from the simulated hydraulic support and buried pressure sensor provided effective information that was linked with stress-strain relationship of the working face in ESTCS. The results of the 3D physical model experiments combined with hybrid statistical methods were effective for predicting dynamic hazards in ESTCS.

Quality of Selected Hungarian Coals

USGS Publications Warehouse

Landis, E.R.; Rohrbacher, T.J.; Gluskoter, H.J.; Fodor, B.; Gombar, G.

2007-01-01

As part of a program conducted jointly by the U.S. Geological Survey and the Hungarian Geological Survey under the auspices of the United States-Hungarian Science and Technology Fund, a total of 39 samples from five coal mines in Hungary were selected for analysis. The mine areas sampled represent most of the coal mined recently in Hungary. Almost all the coal is used to generate electricity. Coals from the five mines (four underground, one surface) reflect differences in age, depositional setting, organic and inorganic components of the original sediments, and deformational history. Classified according to the ranking system of the American Society for Testing and Materials, the coals range in rank from lignite B (Pliocene[?] coals) to high volatile A bituminous (Jurassic coals). With respect to grade classification, based on seam-weighted averages of moisture, ash, and sulfur contents: (1) all contain high moisture (more than 10 percent), (2) all except the Eocene coals are high (more than 15 percent) in ash yield, and (3) two (Jurassic and Eocene coals) are high in sulfur (more than 3 percent) and three (Cretaceous, Miocene, and Pliocene coals) have medium sulfur contents (1 to 3 percent). Average heat values range from 4,000 to 8,650 British thermal units per pound.

Geomorphology of coal seam fires

NASA Astrophysics Data System (ADS)

Kuenzer, Claudia; Stracher, Glenn B.

2012-02-01

Coal fires occur in underground natural coal seams, in exposed surface seams, and in coal storage or waste piles. The fires ignite through spontaneous combustion or natural or anthropogenic causes. They are reported from China, India, USA, South Africa, Australia, and Russia, as well as many other countries. Coal fires lead to loss of a valuable resource (coal), the emission of greenhouse-relevant and toxic gases, and vegetation deterioration. A dangerous aspect of the fires is the threat to local mines, industries, and settlements through the volume loss underground. Surface collapse in coal fire areas is common. Thus, coal fires are significantly affecting the evolution of the landscape. Based on more than a decade of experience with in situ mapping of coal fire areas worldwide, a general classification system for coal fires is presented. Furthermore, coal seam fire geomorphology is explained in detail. The major landforms associated with, and induced by, these fires are presented. The landforms include manifestations resulting from bedrock surface fracturing, such as fissures, cracks, funnels, vents, and sponges. Further manifestations resulting from surface bedrock subsidence include sinkholes, trenches, depressions, partial surface subsidence, large surface subsidence, and slides. Additional geomorphologic coal fire manifestations include exposed ash layers, pyrometamorphic rocks, and fumarolic minerals. The origin, evolution, and possible future development of these features are explained, and examples from in situ surveys, as well as from high-resolution satellite data analyses, are presented. The geomorphology of coal fires has not been presented in a systematic manner. Knowledge of coal fire geomorphology enables the detection of underground coal fires based on distinct surface manifestations. Furthermore, it allows judgments about the safety of coal fire-affected terrain. Additionally, geomorphologic features are indicators of the burning stage of fires. Finally, coal fire geomorphology helps to explain landscape features whose occurrence would otherwise not be understood. Although coal fire-induced thermal anomalies and gas release are also indications of coal fire activity, as addressed by many investigators, no assessment is complete without sound geomorphologic mapping of the fire-induced geomorphologic features.

Suitability of ponds formed by strip mining in eastern Oklahoma for public water supply, aquatic life, waterfowl habitat, livestock watering, irrigation, and recreation

USGS Publications Warehouse

Parkhurst, Renee S.

1994-01-01

A study of coal ponds formed by strip mining in eastern Oklahoma included 25 ponds formed by strip mining from the Croweburg, McAlester, and Iron Post coal seams and 6 noncoal-mine ponds in the coal-mining area. Water-quality samples were collected in the spring and summer of 1985 to determine the suitability of the ponds for public water supply, aquatic life, waterfowl habitat, livestock watering, irrigation, and recreation. The rationale for water-quality criteria and the criteria used for each proposed use are discussed. The ponds were grouped by the coal seam mined or as noncoal-mine ponds, and the number of ponds from each group containing water that exceeded a given criterion is noted. Water in many of the ponds can be used for public water supplies if other sources are not available. Water in most of these ponds exceeds one or more secondary standards, but meets all primary standards. Water samples from the epilimnion (shallow strata as determined by temperature) of six ponds exceeded one or more primary standards, which are criteria protective of human health. Water samples from five of eight Iron Post ponds exceeded the selenium criterion. Water samples from all 31 ponds exceeded one or more secondary standards, which are for the protection of human welfare. The criteria most often exceeded were iron, manganese, dissolved solids, and sulfate, which are secondary standards. The criteria for iron and manganese were exceeded more frequently in the noncoal-mine ponds, whereas ponds formed by strip mining were more likely to exceed the criteria for dissolved solids and sulfate. The ponds are marginally suited for aquatic life. Water samples from the epilimnion of 18 ponds exceeded criteria protective of aquatic life. The criteria for mercury and iron were exceeded most often. Little difference was detected between mine ponds and noncoal-mine ponds. Dissolved oxygen concentrations in the hypolimnion (deepest strata) of all the ponds were less than the minimum criterion during the summer. This decreases available fish habitat and affects the type and number of benthic invertebrates. The ponds are generally well suited for use by wintering and migrating waterfowl. Thirteen of the ponds contained water that exceeded the pH, alkalinity, and selenium criteria. The noncoal-mine ponds had the largest percentage of ponds exceeding pH and alkalinity criteria. Water samples from five of eight Iron Post ponds exceeded the selenium criterion. All ponds are generally unsuitable as waterfowl habitat during the summer because of high temperatures and low dissolved oxygen. Most of the ponds are well suited for livestock watering. Water samples from the epilimnion of 29 ponds met all chemical and physical criteria. Water samples from five ponds exceeded the criteria in the hypolimnion. Mine ponds exceeded chemical and physical criteria more often than noncoal-mine ponds. All the ponds contained phytoplankton species potentially toxic to livestock. Water from most of the ponds is marginally suitable for irrigation of sensitive crops, but is more suitable for irrigation of semitolerant and tolerant crops. Most major cash crops grown in eastern Oklahoma are semitolerant and tolerant crops. Water from the epilimnion of 14 ponds was suitable for irrigation under almost all conditions. Water from the epilimnion of 20 ponds was suitable for irrigation of semitolerant crops, and water from the epilimnion of 25 ponds is suitable for irrigation of tolerant crops. The dissolved solids criterion was exceeded the most often. Most of the ponds would not be suitable for swimming. The pH criterion was exceeded in 17 ponds and turbidity restricts visibility needed for diving in 23 ponds. Little difference was detected between mine ponds and noncoal-mine ponds. Many of the ponds formed by strip mining have steep banks that may be dangerous to swimmers.

Application of Foam-gel Technique to Control CO Exposure Generated During Spontaneous Combustion of Coal in Coal Mines.

PubMed

Ren, Xing W; Wang, Feng Z; Guo, Qing; Zuo, Zhao B; Fang, Qi S

2015-01-01

In China, 47.3% of state-owned coal mines are located in coal seams that are prone to spontaneous combustion. The spontaneous combustion of coal is the main cause of the generation of a large amount of carbon monoxide, which can cause serious health issues to miners. A new technique using foam-gel formation was developed to effectively control the spontaneous combustion of coal. The gel can capture more than 90% of the water in the grout and at the same time the foam can cover dangerous areas in the goaf by stacking and cooling of foam in all directions. In this study, a mechanism of foam-gel formation was introduced and the optimal proportions of additives were defined based on experiments of different foaming properties, gelling time and water loss rate as the main index parameters. The results of a field application in a coal mine promise that this new technique would effectively prevent coal oxidation in the goaf and reduce the generation of carbon monoxide.

Efficiency of Low-Profile External Dumping at Open Pit Coal Mining in Kemerovo Region

NASA Astrophysics Data System (ADS)

Selyukov, Alexey; Ermolaev, Vyacheslav; Kostinez, Irina

2017-11-01

Kemerovo region is one of the largest industrial regions of Russia, with a raw material specialization. The rapid growth of the coal industry in recent years has been greatly facilitated by the expansion and development of open pit mining for coal seams extraction, accompanied by an increase in the volumes of overburden and the height of the dumps. There are about 400 objects in the Russian Federation Government Register of Waste Disposal Facilities 80% of which are dumps. Approaches both to external dumping and to the technical stage of reclamation currently contribute to the growth of geomorphic system's instability. Thus, it is proposed to slightly change the approaches to external dumping: the essence consists in the formation of an external dump of overburden, which in future would represent a favorable landscape unit of a flat surface relief used for subsequent differently directed purposes.

Requirements for the conceptual design of advanced underground coal extraction systems

NASA Technical Reports Server (NTRS)

Gangal, M. D.; Lavin, M. L.

1981-01-01

Conceptual design requirements are presented for underground coal mining systems having substantially improved performance in the areas of production cost and miner safety. Mandatory performance levels are also set for miner health, environmental impact, and coal recovery. In addition to mandatory design goals and constraints, a number of desirable system characteristics are identified which must be assessed in terms of their impact on production cost and their compatibility with other system elements. Although developed for the flat lying, moderately thick seams of Central Appalachia, these requirements are designed to be easily adaptable to other coals.

Application of growing nested Petri nets for modeling robotic systems operating under risk

NASA Astrophysics Data System (ADS)

Sorokin, E. V.; Senkov, A. V.

2017-10-01

The paper studies the peculiarities of modeling robotic systems engaged in mining. Existing modeling mechanisms are considered, which are based on nested Petri nets, and a new formalism of growing Petri nets is presented that allows modeling robotic systems operating under risk. Modeling is provided both for the regular operation mode and for non-standard modes in which individual elements of the system can perform uncharacteristic functions. The example shows growing Petri nets that are used for modeling extraction of flat coal seams by a robotic system consisting of several different-type autonomous robots.

Mineralogical and microstructural investigations of fractures in Permian z2 potash seam and surrounding salt rocks

NASA Astrophysics Data System (ADS)

Mertineit, Michael; Grewe, Wiebke; Schramm, Michael; Hammer, Jörg; Blanke, Hartmut; Patzschke, Mario

2017-04-01

Fractures occur locally in the z2 potash seam (Kaliflöz Staßfurt). Most of them extend several centimeter to meter into the surrounding salt rocks. The fractures are distributed on all levels in an extremely deformed area of the Morsleben salt mine, Northern Germany. The sampling site is located within a NW-SE trending synclinal structure, which was reverse folded (Behlau & Mingerzahn 2001). The samples were taken between the -195 m and - 305 m level at the field of Marie shaft. In this area, more than 200 healed fractures were mapped. Most of them show opening widths of only a few millimeters to rarely 10 cm. The fractures in rock salt are filled with basically polyhalite, halite and carnallite. In the potash seam, the fractures are filled with kainite, halite and minor amounts of carnallite and polyhalite. In some cases the fracture infill changes depending on the type of surrounding rocks. There are two dominant orientations of the fractures, which can be interpreted as a conjugated system. The main orientation is NE-SW trending, the dip angles are steep (ca. 70°, dip direction NW and SE, respectively). Subsequent deformation of the filled fractures is documented by a strong grain shape fabric of kainite, undulatory extinction and subgrain formation in kainite, and several mineral transformations. Subgrain formation in halite occurred in both, the fracture infill and the surrounding salt rocks. The results correlate in parts with investigations which were carried out at the close-by rock salt mine Braunschweig-Lüneburg (Horn et al. 2016). The development of the fractures occurred during compression of clayey salt rocks. However, the results are only partly comparable due to different properties (composition, impurities) of the investigated stratigraphic units. Further investigations will focus on detailed microstructural and geochemical analyses of the fracture infill and surrounding salt rocks. Age dating of suitable minerals, e.g. polyhalite (Leitner et al. 2013), could help to reconstruct the formation conditions. Behlau, J. & Mingerzahn, G. 2001. Geological and tectonic investigations in the former Morsleben salt mine (Germany) as a basis for the safety assessment of a radioactive waste repository. Engineering Geology 61, 83-97. Leitner, C., Neubauer, F., Genser, J., Borojevic-Sostaric, S. & Rantitsch, G. 2013. 40Ar/39Ar ages of crystallization and recrystallization of rock-forming polyhalite in Alpine rocksalt deposits. In: Jourdan, F., Mark, D.F. & Verati, C. (eds.): Advances in 40Ar/39Ar dating from archaeology to planetary sciences. - Geological Society of London, Special Publications 378, 207-224. Horn, M., Barnasch, J., Bode, J., Stanek, K. & Zeibig, S. 2016. Erscheinungsformen der bruchlosen Deformation und Bruchdeformation im Salinar des Steinsalzbergwerkes Braunschweig-Lüneburg. Kali und Steinsalz 02/2016, 30-42.

Microbially-Enhanced Coal Bed Methane: Strategies for Increased Biogenic Production

NASA Astrophysics Data System (ADS)

Davis, K.; Barhart, E. P.; Schweitzer, H. D.; Cunningham, A. B.; Gerlach, R.; Hiebert, R.; Fields, M. W.

2014-12-01

Coal is the largest fossil fuel resource in the United States. Most of this coal is deep in the subsurface making it costly and potentially dangerous to extract. However, in many of these deep coal seams, methane, the main component of natural gas, has been discovered and successfully harvested. Coal bed methane (CBM) currently accounts for approximately 7.5% of the natural gas produced in the U.S. Combustion of natural gas produces substantially less CO2 and toxic emissions (e.g. heavy metals) than combustion of coal or oil thereby making it a cleaner energy source. In the large coal seams of the Powder River Basin (PRB) in southeast Montana and northeast Wyoming, CBM is produced almost entirely by biogenic processes. The in situ conversion of coal to CBM by the native microbial community is of particular interest for present and future natural gas sources as it provides the potential to harvest energy from coal seams with lesser environmental impacts than mining and burning coal. Research at Montana State University has shown the potential for enhancing the subsurface microbial processes that produce CBM. Long-term batch enrichments have investigated the methane enhancement potential of yeast extract as well as algal and cyanobacterial biomass additions with increased methane production observed with all three additions when compared to no addition. Future work includes quantification of CBM enhancement and normalization of additions. This presentation addresses the options thus far investigated for increasing CBM production and the next steps for developing the enhanced in situ conversion of coal to CBM.

The Census of Marine Life on Seamounts: results from a global science program

NASA Astrophysics Data System (ADS)

Stocks, K.; Clark, M.; Rowden, A.; Consalvey, M.

2010-12-01

CenSeam (a Global Census of Marine Life on Seamounts) is a network of more than 500 scientists, policy makers and conservationists around the world. These participants are collaborating to increase our understanding of the factors driving seamount community composition and diversity, such that we can better understand and manage the effects of human activities. The major scientific outcomes of the CenSeam community include the findings that 1) Seamount community composition is often similar to surrounding habitats; however, community structure can be different. 2) Contrary to conventional wisdom, few seamounts follow island biogeography predictions. 3) Seamounts can support a higher benthic biomass than surrounding habitats. 4) Seamounts can support species and communities new to science, and represent range extensions for known species, which are being described from CenSeam voyages. 5) For the first time, the extent of the vulnerability and risk to seamount benthic communities from fishing has been quantified. 6) Whilst long assumed, CenSeam researchers have demonstrated that seamount communities are disturbed by fishing and are slow to recover. And 7) Seamounts might act as repositories of biodiversity during future periods of extreme environmental change, as they have likely done in the past. The major products of Censeam include 1) a book synthesizing seamount knowledge: Seamounts: Ecology, Fisheries and Conservation (from Blackwell Publishing); 2) a recent review of the structure and function of seamount benthic communities, human impacts, and seamount management and conservation (Ann Rev Mar Sci); 3) hundreds of scientific publications, including Special Issues in Marine Ecology and Oceanography (in collaboration with the Seamount Biogeogsciences Network), and a Special Collection in PLoSONE; 4) guidance documents and formal advising for seamount management communities, including the United Nations Environment Program, International Seabed Authority, Convention on Biological Diversity, and Regional Fisheries Management Organizations; 5) protocols manuals and guides to facilitate standardization of methodology, including a Wiley Blackwell book, Biological Sampling in the Deep-Sea, due to be published 2011; and 6) SeamountsOnline, a central database of global seamount data (5500 taxa from 258 seamounts) to support research and management (seamounts.sdsc.edu). CenSeam has also had Societal impacts. It has fostered collaborative research to expand global seamount sampling to previously understudied regions. It has increased public awareness of seamounts and the wider deep-sea, for example through expedition web logs to share the experiences of researchers at sea. And CenSeam has provided quality science to inform the management of commercial fisheries and mining, such as a practical seamount classification scheme for protected area planning, and maps of predicted coral habitat suitability.

Interconnections Seam Study | Energy Analysis | NREL

Science.gov Websites

Interconnections Seam Study Interconnections Seam Study Through the Interconnections Seam Study between the interconnections. This study will quantify the value of strengthening the connections (or Peer Review - Interconnections Seam Study to learn more. Our Approach To quantify the value of

Roof instability characteristics and pre-grouting of the roof caving zone in residual coal mining

NASA Astrophysics Data System (ADS)

Zhao, Tong; Liu, Changyou

2017-12-01

Abandoned roadways and roof caving zones are commonly found in residual coal, and can destroy the integrity of the coal seam and roof. Resulting from mining-induced stress, continuous collapse and fracture instability in roof caving zones (RCZs) jeopardize the safety and efficiency of residual coal mining. Based on the engineering geology conditions of remining face 3101 in Shenghua Mine, the roof fracture and instability features of the RCZ were analyzed through physical simulation, theoretical analysis, and field measurements. In this case, influenced by the RCZ, the main roof across the RCZ fractured and rotated towards the goaf, greatly increasing the working resistance, and crushing the supports. The sudden instability of the coal pillars weakened its support of the main roof, thus resulting in long-key blocks across the RCZ and hinged roof structures, which significantly decreased the stability of the underlying immediate roof. This study establishes a mechanical model for the interactions between the surrounding rock and the supports in the RCZ, determines the reasonable working resistance, and examines the use of pre-grouting solidification restoration technology (PSRT) to solidify the RCZ and reinforce the coal pillars—thus increasing their bearing capacity. Field measurements revealed no roof flaking, inhomogeneous loading or support crushing, indicating that the PSRT effectively controlled the surrounding rock of the RCZ.

Determination of technological parameters in strip mining by time-of-flight and image processing

NASA Astrophysics Data System (ADS)

Elandaloussi, Frank; Mueller, B.; Osten, Wolfgang

1999-09-01

The conveying and dumping of earth masses lying over the coal seam in lignite surface mining is done usually by overburden conveyor bridges. The overburden, obtained from connected excavators, is transported over the bridge construction using a conveyor belt system and poured into one front dump and three surface dumps. The shaping of the dump growth is of great importance both to guaranty the stability of the masses dumped to earth stocks as well as the whole construction and to prepare the area for re-cultivation. This article describes three measurement systems: one to determine the impact point of the dumped earth masses, one to determine the shape of the entire mining process and the other a sensor for the loading of the conveyor belt. For the first measurement system, a real-time video system has been designed, set-up and installed that is capable to determine the impact point of all three dumps simultaneously. The second measurement system is a connection of 5 special designed laser distance measuring instruments, that are able to measure the shape of the mining process under unfavorable environmental conditions like dust, high temperature changes, heavy shocks etc. The third sensor is designed for monitoring the transportation of the masses via the conveyor belt system.

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

NASA Astrophysics Data System (ADS)

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.

Using Drone Imagery and Photogrammetry to Map Basin Stratigraphy and Structures Exposed in Mine, Road, and Arroyo Outcrops, Santa Rosalia, Baja California Sur, Mexico

NASA Astrophysics Data System (ADS)

Banes, A.; Alvarez Ortega, K. G.; Henry, M.; Niemi, T.

2017-12-01

During the 2017 Baja Basins Research Experience for Undergraduates (REU), a DJI Phantom 3 Advanced Quadcopter drone equipped with a GPS-enabled, 12 Megapixel camera was manually flown to collect aerial photographs of several geologic outcrops on the Minera Boléo and Lucifer mines in central Baja California Sur. The strip mine faces, roadcuts, and arroyos exposed Neogene to Quaternary sediments of the Santa Rosalía basin including the basal Cu-Zn-Mn-Co-bearing Miocene Boléo Formation that is actively being mined. It is overlain by Plio-Quaternary marine and non-marine deposits. Photographs were collected with a 70% overlap and processed into geographically-referenced, orthophotomosaics using Agisoft Photoscan. The output models have an adequate resolution for viewing bedding and fault characteristics. Measurements can be made inside the 3D models, making drones a useful tool for studying the geometry of stratigraphic, structural, and geomorphologic features. The studied sites included: 1) roadcuts on Mesa Soledad that exposed oblique-slip faults and syntectonically deposited non-marine and marine conglomerates and sandy, fossil-rich Pliocene beach sediment; 2) outcrops of the Boléo Fm in the Texcoco mine area that showed the detailed stratigraphic relationship between ore seams (mantos) and faults; 3) outcrops where sandstone samples were collected for detrital zircon geochronology; 4) strip mine 3120 that exposed faults and folds in the Boléo Formation; and 5) faults in Miocene volcanic rocks in the Arroyo Infierno near the Lucifer mine. This study shows that photogrammetry and modeling of geologic structures exposed in mine and road outcrops can provide useful information for reconstructing basin architecture and clarifying structural evolution of the Santa Rosalia Basin.

Utilization of coal mine methane for methanol and SCP production. Topical report, May 5, 1995--March 4, 1996

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1998-12-31

The feasibility of utilizing a biological process to reduce methane emissions from coal mines and to produce valuable single cell protein (SCP) and/or methanol as a product has been demonstrated. The quantities of coal mine methane from vent gas, gob wells, premining wells and abandoned mines have been determined in order to define the potential for utilizing mine gases as a resource. It is estimated that 300 MMCFD of methane is produced in the United States at a typical concentration of 0.2-0.6 percent in ventilation air. Of this total, almost 20 percent is produced from the four Jim Walter Resourcesmore » (JWR) mines, which are located in very gassy coal seams. Worldwide vent gas production is estimated at 1 BCFD. Gob gas methane production in the U.S. is estimated to be 38 MMCFD. Very little gob gas is produced outside the U.S. In addition, it is estimated that abandoned mines may generate as much as 90 MMCFD of methane. In order to make a significant impact on coal mine methane emissions, technology which is able to utilize dilute vent gases as a resource must be developed. Purification of the methane from the vent gases would be very expensive and impractical. Therefore, the process application must be able to use a dilute methane stream. Biological conversion of this dilute methane (as well as the more concentrated gob gases) to produce single cell protein (SCP) and/or methanol has been demonstrated in the Bioengineering Resources, Inc. (BRI) laboratories. SCP is used as an animal feed supplement, which commands a high price, about $0.11 per pound.« less

Supporting technology of roadside in gob-side entry in 110 longwall mining method

NASA Astrophysics Data System (ADS)

He, Manchao; Guo, Pengfei; Chen, Shangyuan; Gao, Yubing; Wang, Yajun

2017-05-01

To get better results of shaping roadside in 110 longwall mining method, the roadside support can be reasonably choose and designed through theoretical analysis, engineering test and other methods. The roadway support need to be designed based on the mining height and influence of mining pressure, and it is necessary to consider the "limited deformation" but also "given deformation". Because of the small mining high and short time under mining pressure effect in thin coal seam, roadside support can meet the requirements of block rock from gob using I-steel, but I-steel can't satisfy the deformation of roadway roof and easily lead to I-steel flexural buckling. In that condition we should use the U-steel that can compatible deformation with subsidence of roadway roof and enough torque in overlapping part between tow U-steel should be given when the U-steel is used to support gangue from gob and the U steel assembling two cards can coordinal deformation in dynamic pressure area keeping constant resistance with the deformation of roadway roof and can get a good effect. Through field test, due to the great impact force of the gangue from gob, single props and I-steel and U-steel are easily knocked down when the mining height is more than 4m. For large mining height, gangue blocking hydraulic support is designed and developed which can guarantee the stability and integrity of the roadway roof in the dynamic pressure area and can prevent the impact of gangue from gob. So it has better effect of forming roadway side using gangue from gob. According to above classification, the field experiments were carried out and obtained satisfactory results.

Numerical Modeling of Exploitation Relics and Faults Influence on Rock Mass Deformations

NASA Astrophysics Data System (ADS)

Wesołowski, Marek

2016-12-01

This article presents numerical modeling results of fault planes and exploitation relics influenced by the size and distribution of rock mass and surface area deformations. Numerical calculations were performed using the finite difference program FLAC. To assess the changes taking place in a rock mass, an anisotropic elasto-plastic ubiquitous joint model was used, into which the Coulomb-Mohr strength (plasticity) condition was implemented. The article takes as an example the actual exploitation of the longwall 225 area in the seam 502wg of the "Pokój" coal mine. Computer simulations have shown that it is possible to determine the influence of fault planes and exploitation relics on the size and distribution of rock mass and its surface deformation. The main factor causing additional deformations of the area surface are the abandoned workings in the seam 502wd. These abandoned workings are the activation factor that caused additional subsidences and also, due to the significant dip, they are a layer on which the rock mass slides down in the direction of the extracted space. These factors are not taken into account by the geometrical and integral theories.

49 CFR 178.33-6 - Manufacture.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Seams when used must be as follows: (1) Circumferential seams: By welding, swedging, brazing, soldering, or double seaming. (2) Side seams: By welding, brazing, or soldering. (c) Ends: The ends shall be of...

49 CFR 178.33-6 - Manufacture.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Seams when used must be as follows: (1) Circumferential seams: By welding, swedging, brazing, soldering, or double seaming. (2) Side seams: By welding, brazing, or soldering. (c) Ends: The ends shall be of...

49 CFR 178.33-6 - Manufacture.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Seams when used must be as follows: (1) Circumferential seams: By welding, swedging, brazing, soldering, or double seaming. (2) Side seams: By welding, brazing, or soldering. (c) Ends: The ends shall be of...

49 CFR 178.33-6 - Manufacture.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Seams when used must be as follows: (1) Circumferential seams: By welding, swedging, brazing, soldering, or double seaming. (2) Side seams: By welding, brazing, or soldering. (c) Ends: The ends shall be of...

49 CFR 178.33a-6 - Manufacture.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Seams when used must be as follows: (1) Circumferential seams. By welding, swedging, brazing, soldering, or double seaming. (2) Side seams. By welding, brazing or soldering. (c) Ends. The ends shall be of...

49 CFR 178.33a-6 - Manufacture.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Seams when used must be as follows: (1) Circumferential seams. By welding, swedging, brazing, soldering, or double seaming. (2) Side seams. By welding, brazing or soldering. (c) Ends. The ends shall be of...

49 CFR 178.33a-6 - Manufacture.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Seams when used must be as follows: (1) Circumferential seams. By welding, swedging, brazing, soldering, or double seaming. (2) Side seams. By welding, brazing or soldering. (c) Ends. The ends shall be of...

49 CFR 178.33a-6 - Manufacture.

Code of Federal Regulations, 2011 CFR

2011-10-01

...) Seams when used must be as follows: (1) Circumferential seams. By welding, swedging, brazing, soldering, or double seaming. (2) Side seams. By welding, brazing or soldering. (c) Ends. The ends shall be of...

A Model of Equilibrium Conditions of Roof Rock Mass Giving Consideration to the Yielding Capacity of Powered Supports

NASA Astrophysics Data System (ADS)

Jaszczuk, Marek; Pawlikowski, Arkadiusz

2017-12-01

The work presents the model of interactions between the powered roof support units and the rock mass, while giving consideration to the yielding capacity of the supports - a value used for the analysis of equilibrium conditions of roof rock mass strata in geological and mining conditions of a given longwall. In the model, the roof rock mass is kept in equilibrium by: support units, the seam, goafs, and caving rocks (Fig. 1). In the assumed model of external load on the powered roof support units it is a new development - in relation to the model applied in selection of supports based on the allowable deflection of roof theory - that the load bearing capacity is dependent on the increment of the inclination of the roof rock mass and on the properties of the working medium, while giving consideration to the air pockets in the hydraulic systems, the load of the caving rocks on the caving shield, introducing the RA support value of the roof rock mass by the coal seam as a closed-form expression and while giving consideration to the additional support provided by the rocks of the goaf as a horizontal component R01H of the goaf reaction. To determine the roof maintenance conditions it is necessary to know the characteristics linking the yielding capacity of the support units with the heading convergence, which may be measured as the inclination angle of the roof rock mass. In worldwide mining, Ground Reaction Curves are used, which allow to determine the required yielding capacity of support units based on the relation between the load exerted on the unit and the convergence of the heading ensuring the equilibrium of the roof rock mass. (Figs. 4 and 8). The equilibrium of the roof rock mass in given conditions is determined at the displacement of the rock mass by the α angle, which impacts the following values: yielding capacity of units FN, vertical component of goaf reaction R01V and the horizontal component of goaf reaction R01H. In the model of load on the support units giving consideration to the load of the caving shield, a model of support unit was used that allows for unequivocal determination of the yielding capacity of the support with consideration given to the height of the unit in use and the change in the inclination of the canopy resulting from the displacement of the roof of the longwall. The yielding capacity of the support unit and its point of application on the canopy was determined using the method of units which allows for the internal forces to be manifested. The weight of the rock mass depends on the geological and mining conditions, for which the shape and dimensions of the rock mass affecting the support unit are determined. The resultant force of the pressure of gob on the gob shield was calculated by assuming that the load may be understood as a pressure of ground on a wall. This required the specification of the volume of the fallen rocks that affect the unit of powered roof supports (Fig. 2). To determine the support of the roof rock mass by the coal seam, experience of the Australian mining industry was used. Experiments regarding the strength properties of coal have exhibited that vertical deformation, at which the highest seam reaction occurs while supporting the roof rock mass, amounts to 0.5% of the longwall's height. The measure of the width of the contact area between the rock mass and the seam is the width of the additional uncovering of the face roof due to spalling of seam topcorners da (Fig. 2). With the above parameters and the value of the modulus of elasticity of coal in mind, the value of the seam's reaction may be estimated using the dependence (2). The vertical component of the goafs' reaction may be determined based on the strength characteristics of the fallen roof, the contact area of the rock mass with the fallen roof and the mean strain of the fallen roof at the area of contact. In the work by Pawlikowski (2014), a research procedure was proposed which encompasses model tests and exploitation tests of the loads exerted on the support units, aimed at the determination of the vertical component of the goaf reaction (Fig. 5). Based on duty cycles of powered roof support units, a mean value of the indicator of contact stiffness between the roof rock mass and the rocks constituting the caving is determined, assuming the linear dependence between the horizontal reaction and the heading convergence. The parameter allows for the determination of the horizontal component of the goafs' reaction in the external loading model of support units and allows for the determination of the required yielding capacity of supports, required to ensure the equilibrium of the roof rock mass. The experimentally verified model of the external loading of the units was used to conduct simulations of interactions between the KOPEX-095/17-POz support unit and the rock mass in a face characterized by the height of 1.6 m. Based on the data obtained in experiment, the variability of the yielding capacity of the support units was analyzed. A yielding capacity inclination angle of the units was determined for the registered curves (Figs. 6 and 7). At the same time, the presentation of the lines corresponding to the required yielding capacity of units and characterizing the deformability of the support units, allows for the prediction of the yielding capacity of the powered supports and the convergence of the heading in the conditions of a given face (Fig. 9).

Change in the magnetic properties of bituminous coal intruded by an igneous dike, Dutch Creek Mine, Pitkin County, Colorado

USGS Publications Warehouse

Thorpe, A.N.; Senftle, F.E.; Finkelman, R.B.; Dulong, F.T.; Bostick, N.H.

1998-01-01

Magnetization measurements have been made on natural coke-coal samples collected at various distances from a felsic porphyry dike in a coal seam in Dutch Creek Mine, Colorado to help characterize the nature and distribution of the iron-bearing phases. The magnetization passes through a maximum at the coke-to-coal transition about 31 cm from the dike contact. The magnetic measurements support the geochemical data indicating that magmatic fluids along with a high-temperature gas pulse moved into the coal bed. Interaction of the magmatic fluids with the coal diminished the reducing power of the thermal gas pulse from the dike to a point about 24 cm into the coal. The hot reducing gas penetrated further and produced a high temperature (~400-525??C) zone (at about 31 cm) just ahead of the magmatic fluids. Metallic iron found in this zone is the principal cause of the observed high magnetization. Beyond this zone, the temperature was too low to alter the coal significantly.Magnetization measurements have been made on natural coke-coal samples collected at various distances from a felsic porphyry dike in a coal seam in Dutch Creek Mine, Colorado to help characterize the nature and distribution of the iron-bearing phases. The magnetization passes through a maximum at the coke-to-coal transition about 31 cm from the dike contact. The magnetic measurements support the geochemical data indicating that magmatic fluids along with a high-temperature gas pulse moved into the coal bed. Interaction of the magmatic fluids with the coal diminished the reducing power of the thermal gas pulse from the dike to a point about 24 cm into the coal. The hot reducing gas penetrated further and produced a high temperature (approximately 400-525 ??C) zone (at about 31 cm) just ahead of the magmatic fluids. Metallic iron found in this zone is the principal cause of the observed high magnetization. Beyond this zone, the temperature was too low to alter the coal significantly.

Inorganic carbon and fossil organic carbon are source of bias for quantification of sequestered carbon in mine spoil

NASA Astrophysics Data System (ADS)

Vindušková, Olga; Frouz, Jan

2016-04-01

Carbon sequestration in mine soils has been studied as a possibility to mitigate the rising atmospheric CO2 levels and to improve mine soil quality (Vindu\\vsková and Frouz, 2013). Moreover, these soils offer an unique opportunity to study soil carbon dynamics using the chronosequence approach (using a set of sites of different age on similar parent material). However, quantification of sequestered carbon in mine soils is often complicated by fossil organic carbon (e.g., from coal or kerogen) or inorganic carbon present in the spoil. We present a methodology for quantification of both of these common constituents of mine soils. Our recommendations are based on experiments done on post-mining soils in Sokolov basin, Czech Republic. Here, fossil organic carbon is present mainly as kerogen Type I and II and represents 2-6 wt.% C in these soils. Inorganic carbon in these soils is present mainly as siderite (FeCO3), calcite (CaCO3), and dolomite (CaMg(CO3)2). All of these carbonates are often found in the overburden of coal seams thus being a common constituent of post-mining soils in the world. Vindu\\vsková O, Frouz J, 2013. Soil carbon accumulation after open-cast coal and oil shale mining in Northern Hemisphere: a quantitative review. ENVIRONMENTAL EARTH SCIENCES, 69: 1685-1698. Vindu\\vsková O, Dvořáček V, Prohasková A, Frouz J. 2014. Distinguishing recent and fossil organic matter - A critical step in evaluation of post-mining soil development - using near infrared spectroscopy. ECOLOGICAL ENGINEERING. 73: 643-648. Vindu\\vsková O, Sebag D, Cailleau G, Brus J, Frouz J. 2015. Methodological comparison for quantitative analysis of fossil and recently derived carbon in mine soils with high content of aliphatic kerogen. ORGANIC GEOCHEMISTRY, 89-90:14-22.

Depth-aware image seam carving.

PubMed

Shen, Jianbing; Wang, Dapeng; Li, Xuelong

2013-10-01

Image seam carving algorithm should preserve important and salient objects as much as possible when changing the image size, while not removing the secondary objects in the scene. However, it is still difficult to determine the important and salient objects that avoid the distortion of these objects after resizing the input image. In this paper, we develop a novel depth-aware single image seam carving approach by taking advantage of the modern depth cameras such as the Kinect sensor, which captures the RGB color image and its corresponding depth map simultaneously. By considering both the depth information and the just noticeable difference (JND) model, we develop an efficient JND-based significant computation approach using the multiscale graph cut based energy optimization. Our method achieves the better seam carving performance by cutting the near objects less seams while removing distant objects more seams. To the best of our knowledge, our algorithm is the first work to use the true depth map captured by Kinect depth camera for single image seam carving. The experimental results demonstrate that the proposed approach produces better seam carving results than previous content-aware seam carving methods.

Weaving Ecosystem Service Assessment into Environmental Impact Assessments of Thar Coal Field: Impact of Coal Mining on Socio-Ecological Systems of Rural Communities.

NASA Astrophysics Data System (ADS)

Hina, A.

2016-12-01

The Research takes into account Block II Mining and Power Plant Project of Thar Coal field in Pakistan by carrying out ecosystem service assessment of the region to identify the impact on important ecosystem service losses and the contribution of mining companies to mitigate the socio-economic problems as a part of their Corporate Social Responsibility (CSR). The study area includes 7 rural settlements, around 921 households and 7000 individuals, dependent on agriculture and livestock for their livelihoods. Currently, the project has adopted the methods of strip mining (also called open-cut mining, open-cast mining, and stripping), undergoing removing the overburden in strips to enable excavation of the coal seams. Since the consequences of mine development can easily spill across community and ecological boundaries, the rising scarcity of some ecosystem services makes the case to examine both project impact and dependence on ecosystem services. A preliminary Ecosystem Service review of Thar Coal Field identifies key ecosystems services owing to both high significance of project impact and high project dependence are highlighted as: the hydrogeological study results indicate the presence of at least three aquifer zones: one above the coal zone (the top aquifer), one within the coal and the third below the coal zone. Hence, Water is identified as a key ecosystem service to be addressed and valued due to its high dependency in the area for livestock, human wellbeing, agriculture and other purposes. Crop production related to agricultural services, in association with supply services such as soil quality, fertility, and nutrient recycling and water retention need to be valued. Cultural services affected in terms of land use change and resettlement and rehabilitation factors are recommended to be addressed.

Depositional setting, petrology and chemistry of Permian coals from the Paraná Basin: 2. South Santa Catarina Coalfield, Brazil

USGS Publications Warehouse

Kalkreuth, W.; Holz, M.; Mexias, A.; Balbinot, M.; Levandowski, J.; Willett, J.; Finkelman, R.; Burger, H.

2010-01-01

In Brazil economically important coal deposits occur in the southern part of the Paran?? Basin, where coal seams occur in the Permian Rio Bonito Formation, with major coal development in the states of Rio Grande de Sul and Santa Catarina. The current paper presents results on sequence stratigraphic interpretation of the coal-bearing strata, and petrological and geochemical coal seam characterization from the South Santa Catarina Coalfield, Paran?? Basin.In terms of sequence stratigraphic interpretation the precursor mires of the Santa Catarina coal seams formed in an estuarine-barrier shoreface depositional environment, with major peat accumulation in a high stand systems tract (Pre-Bonito and Bonito seams), a lowstand systems tract (Ponta Alta seam, seam A, seam B) and a transgressive systems tract (Irapu??, Barro Branco and Treviso seams).Seam thicknesses range from 1.70 to 2.39. m, but high proportions of impure coal (coaly shale and shaley coal), carbonaceous shale and partings reduce the net coal thickness significantly. Coal lithoypes are variable, with banded coal predominant in the Barro Branco seam, and banded dull and dull coal predominantly in Bonito and Irapu?? seams, respectively. Results from petrographic analyses indicate a vitrinite reflectance range from 0.76 to 1.63 %Rrandom (HVB A to LVB coal). Maceral group distribution varies significantly, with the Barro Branco seam having the highest vitrinite content (mean 67.5 vol%), whereas the Irapu?? seam has the highest inertinite content (33.8. vol%). Liptinite mean values range from 7.8. vol% (Barro Branco seam) to 22.5. vol% (Irapu?? seam).Results from proximate analyses indicate for the three seams high ash yields (50.2 - 64.2wt.%). Considering the International Classification of in-Seam Coals, all samples are in fact classified as carbonaceous rocks (>50wt.% ash). Sulfur contents range from 3.4 to 7.7 wt.%, of which the major part occurs as pyritic sulfur. Results of X-ray diffraction indicate the predominance of quartz and kaolinite (also pyrite). Gypsum, gibbsite, jarosite and calcite were also identified in some samples. Feldspar was noted but is rare. The major element distribution in the three seams (coal basis) is dominated by SiO2 (31.3wt.%, mean value), Al2O3 (14.5wt.%, mean value) and Fe2O3 (6.9 wt.%, mean value). Considering the concentrations of trace elements that are of potential environmental hazards the Barro Branco, Bonito and Irapu?? seams (coal base) are significantly enriched in Co (15.7ppm), Cr (54.5ppm), Li (59.3ppm), Mn (150.4ppm), Pb (58.0ppm) and V (99.6ppm), when compared to average trace elements contents reported for U. S. coals.Hierarchical cluster analysis identified, based on similarity levels, three groups of major elements and seven groups of trace elements. Applying discriminant analyses using trace and major element distribution, it could be demonstrated that the three seams from Santa Catarina show distinct populations in the discriminant analyses plots, and also differ from the coals of Rio Grande do Sul analyzed in a previous study. ?? 2010 Elsevier B.V.

A novel weld seam detection method for space weld seam of narrow butt joint in laser welding

NASA Astrophysics Data System (ADS)

Shao, Wen Jun; Huang, Yu; Zhang, Yong

2018-02-01

Structured light measurement is widely used for weld seam detection owing to its high measurement precision and robust. However, there is nearly no geometrical deformation of the stripe projected onto weld face, whose seam width is less than 0.1 mm and without misalignment. So, it's very difficult to ensure an exact retrieval of the seam feature. This issue is raised as laser welding for butt joint of thin metal plate is widely applied. Moreover, measurement for the seam width, seam center and the normal vector of the weld face at the same time during welding process is of great importance to the welding quality but rarely reported. Consequently, a seam measurement method based on vision sensor for space weld seam of narrow butt joint is proposed in this article. Three laser stripes with different wave length are project on the weldment, in which two red laser stripes are designed and used to measure the three dimensional profile of the weld face by the principle of optical triangulation, and the third green laser stripe is used as light source to measure the edge and the centerline of the seam by the principle of passive vision sensor. The corresponding image process algorithm is proposed to extract the centerline of the red laser stripes as well as the seam feature. All these three laser stripes are captured and processed in a single image so that the three dimensional position of the space weld seam can be obtained simultaneously. Finally, the result of experiment reveals that the proposed method can meet the precision demand of space narrow butt joint.

C. elegans GATA factors EGL-18 and ELT-6 function downstream of Wnt signaling to maintain the progenitor fate during larval asymmetric divisions of the seam cells.

PubMed

Gorrepati, Lakshmi; Thompson, Kenneth W; Eisenmann, David M

2013-05-01

The C. elegans seam cells are lateral epithelial cells arrayed in a single line from anterior to posterior that divide in an asymmetric, stem cell-like manner during larval development. These asymmetric divisions are regulated by Wnt signaling; in most divisions, the posterior daughter in which the Wnt pathway is activated maintains the progenitor seam fate, while the anterior daughter in which the Wnt pathway is not activated adopts a differentiated hypodermal fate. Using mRNA tagging and microarray analysis, we identified the functionally redundant GATA factor genes egl-18 and elt-6 as Wnt pathway targets in the larval seam cells. EGL-18 and ELT-6 have previously been shown to be required for initial seam cell specification in the embryo. We show that in larval seam cell asymmetric divisions, EGL-18 is expressed strongly in the posterior seam-fated daughter. egl-18 and elt-6 are necessary for larval seam cell specification, and for hypodermal to seam cell fate transformations induced by ectopic Wnt pathway overactivation. The TCF homolog POP-1 binds a site in the egl-18 promoter in vitro, and this site is necessary for robust seam cell expression in vivo. Finally, larval overexpression of EGL-18 is sufficient to drive expression of a seam marker in other hypodermal cells in wild-type animals, and in anterior hypodermal-fated daughters in a Wnt pathway-sensitized background. These data suggest that two GATA factors that are required for seam cell specification in the embryo independently of Wnt signaling are reused downstream of Wnt signaling to maintain the progenitor fate during stem cell-like divisions in larval development.

C. elegans GATA factors EGL-18 and ELT-6 function downstream of Wnt signaling to maintain the progenitor fate during larval asymmetric divisions of the seam cells

PubMed Central

Gorrepati, Lakshmi; Thompson, Kenneth W.; Eisenmann, David M.

2013-01-01

The C. elegans seam cells are lateral epithelial cells arrayed in a single line from anterior to posterior that divide in an asymmetric, stem cell-like manner during larval development. These asymmetric divisions are regulated by Wnt signaling; in most divisions, the posterior daughter in which the Wnt pathway is activated maintains the progenitor seam fate, while the anterior daughter in which the Wnt pathway is not activated adopts a differentiated hypodermal fate. Using mRNA tagging and microarray analysis, we identified the functionally redundant GATA factor genes egl-18 and elt-6 as Wnt pathway targets in the larval seam cells. EGL-18 and ELT-6 have previously been shown to be required for initial seam cell specification in the embryo. We show that in larval seam cell asymmetric divisions, EGL-18 is expressed strongly in the posterior seam-fated daughter. egl-18 and elt-6 are necessary for larval seam cell specification, and for hypodermal to seam cell fate transformations induced by ectopic Wnt pathway overactivation. The TCF homolog POP-1 binds a site in the egl-18 promoter in vitro, and this site is necessary for robust seam cell expression in vivo. Finally, larval overexpression of EGL-18 is sufficient to drive expression of a seam marker in other hypodermal cells in wild-type animals, and in anterior hypodermal-fated daughters in a Wnt pathway-sensitized background. These data suggest that two GATA factors that are required for seam cell specification in the embryo independently of Wnt signaling are reused downstream of Wnt signaling to maintain the progenitor fate during stem cell-like divisions in larval development. PMID:23633508

Cryogenic Testing of Different Seam Concepts for Multilayer Insulation Systems

NASA Technical Reports Server (NTRS)

Johnson, Wesley L.; Fesmire, J. E.

2009-01-01

Recent testing in a cylindrical, comparative cryostat at the Cryogenics Test Laboratory has focused on various seam concepts for multilayer insulation systems. Three main types of seams were investigated: straight overlap, fold-over, and roll wrapped. Each blanket was comprised of 40 layer pairs of reflector and spacer materials. The total thickness was approximately 12.5-mm, giving an average layer density of 32 layers per centimeter. The blankets were tested at high vacuum, soft vacuum, and no vacuum using liquid nitrogen to maintain the cold boundary temperature at 77 K. Test results show that all three seam concepts are all close in thermal performance; however the fold-over method provides the lowest heat flux. For the first series of tests, seams were located 120 degrees around the circumference of the cryostat from the previous seam. This technique appears to have lessened the degradation of the blanket due to the seams. In a follow-on test, a 20 layer blanket was tested in a roll wrapped configuration and then cut down the side of the cylinder, taped together, and re-tested. This test result shows the thermal performance impact of having the seams all in one location versus having the seams clocked around the vessel. This experimental investigation indicates that the method of joining the seams in multilayer insulation systems is not as critical as the quality of the installation process.

Cell contact regulates neuroblast formation in the Caenorhabditis elegans lateral epidermis.

PubMed

Austin, J; Kenyon, C

1994-02-01

A single line of epidermal seam cells lies along each side of the nematode C. elegans. During normal development, one of these cells, V5, produces a neuroblast that will give rise to a sensory structure, the postdeirid. If seam cells located either anterior or posterior to V5 are ablated however, this neuroblast formation is blocked. Because of this requirement for the presence of adjacent seam cells, we have asked whether V5's ability to produce a neuroblast depends on direct contact with its seam cell neighbors. We find that direct contact between seam cells is required for commitment to neuroblast production. Seam cells lose and reform their contacts with each other as they go through rounds of cell division during larval development. Signaling required for neuroblast formation occurs when the seam cells make contact after their first round of division. If this contact is prevented, no neuroblast is made; when it is delayed, the time of signaling is also delayed. The characteristics of these signals suggest that a seam cell must be part of a continuous epithelium in order to develop normally and that signaling may occur via a cell recognition/cell adhesion pathway. The effect of seam cell ablations on neuroblast formation is altered in mab-5(-) animals, suggesting that this HOM-C gene is part of the pathway by which seam cell signaling controls the decision to make a postdeirid neuroblast.

Use of barium-strontium carbonatite for flux welding and surfacing of mining machines

NASA Astrophysics Data System (ADS)

Kryukov, R. E.; Kozyrev, N. A.; Usoltsev, A. A.

2017-09-01

The results of application of barium-strontium carbonatite for modifying and refining iron-carbon alloys, used for welding and surfacing in ore mining and smelting industry, are generalized. The technology of manufacturing a flux additive containing 70 % of barium-strontium carbonatite and 30 % of liquid glass is proposed. Several compositions of welding fluxes based on silicomanganese slag were tested. The flux additive was introduced in an amount of 1, 3, 5 %. Technological features of welding with the application of the examined fluxes are determined. X-ray spectral analysis of the chemical composition of examined fluxes, slag crusts and weld metal was carried out, as well as metallographic investigations of welded joints. The principal possibility of applying barium-strontium carbonatite as a refining and gas-protective additive for welding fluxes is shown. The use of barium-strontium carbonatite reduces the contamination of the weld seam with nonmetallic inclusions: non-deforming silicates, spot oxides and brittle silicates, and increases the desulfurizing capacity of welding fluxes.

An Impact of Mechanical Stress in Coal Briquettes on Sorption of Carbon Dioxide

NASA Astrophysics Data System (ADS)

Wierzbicki, Mirosław

2017-09-01

The presence of gases (methane or carbon dioxide) in hard coal is connected with numerous threats for miners employed in underground mining facilities. When analyzing the coal-methane system, it is necessary to determine the relationship between pressure and gas sorption. Such a relationship should be determined under conditions similar to the natural ones - when it comes to both temperature and pressure. The present paper discusses the results of research conducted with the use of coal briquettes under the state of mechanical stress. Carbon dioxide sorption isotherms were determined for different values of stress affecting the coal material. For five coal samples collected in different mines of the Upper Silesian Coal Basin, Langmuir's sorption isotherms were determined. The results point to significant impact that mechanical stress has upon the sorption process. It is about 1 percent of the value obtained for coal not subjected to stress per 1 MPa. The research results can also prove useful when analyzing hard coal seams from the perspective of their carbon dioxide sequestration abilities.

18 CFR 270.302 - Occluded natural gas produced from coal seams.

Code of Federal Regulations, 2014 CFR

2014-04-01

... produced from coal seams. 270.302 Section 270.302 Conservation of Power and Water Resources FEDERAL ENERGY... produced from coal seams. A person seeking a determination that natural gas is occluded natural gas produced from coal seams must file an application with the jurisdictional agency which contains the...

18 CFR 270.302 - Occluded natural gas produced from coal seams.

Code of Federal Regulations, 2012 CFR

2012-04-01

... produced from coal seams. 270.302 Section 270.302 Conservation of Power and Water Resources FEDERAL ENERGY... produced from coal seams. A person seeking a determination that natural gas is occluded natural gas produced from coal seams must file an application with the jurisdictional agency which contains the...

18 CFR 270.302 - Occluded natural gas produced from coal seams.

Code of Federal Regulations, 2010 CFR

2010-04-01

... produced from coal seams. 270.302 Section 270.302 Conservation of Power and Water Resources FEDERAL ENERGY... produced from coal seams. A person seeking a determination that natural gas is occluded natural gas produced from coal seams must file an application with the jurisdictional agency which contains the...

18 CFR 270.302 - Occluded natural gas produced from coal seams.

Code of Federal Regulations, 2011 CFR

2011-04-01

... produced from coal seams. 270.302 Section 270.302 Conservation of Power and Water Resources FEDERAL ENERGY... produced from coal seams. A person seeking a determination that natural gas is occluded natural gas produced from coal seams must file an application with the jurisdictional agency which contains the...

18 CFR 270.302 - Occluded natural gas produced from coal seams.

Code of Federal Regulations, 2013 CFR

2013-04-01

... produced from coal seams. 270.302 Section 270.302 Conservation of Power and Water Resources FEDERAL ENERGY... produced from coal seams. A person seeking a determination that natural gas is occluded natural gas produced from coal seams must file an application with the jurisdictional agency which contains the...

49 CFR 230.30 - Lap-joint seam boilers.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 49 Transportation 4 2010-10-01 2010-10-01 false Lap-joint seam boilers. 230.30 Section 230.30..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Boilers and Appurtenances Inspection and Repair § 230.30 Lap-joint seam boilers. Every boiler having lap-joint longitudinal seams...

Dips, ramps, and rolls- Evidence for paleotopographic and syn-depositional fault control on the Western Kentucky No. 4 coal bed, tradewater formation (Bolsovian) Illinois Basin

USGS Publications Warehouse

Greb, S.F.; Eble, C.F.; Williams, D.A.; Nelson, W.J.

2001-01-01

The Western Kentucky No. 4 coal is a high-volatile B to high-volatile C bituminous coal that has been heavily mined along the southern margin of the Western Kentucky Coal Field. The seam has a reputation for rolling floor elevation. Elongate trends of floor depressions are referred to as "dips" and "rolls" by miners. Some are relatively narrow and straight to slightly curvilinear in plan view, with generally symmetric to slightly asymmetric cross-sections. Others are broader and asymmetric in section, with sharp dips on one limb and gradual, ramp-like dips on the other. Some limbs change laterally from gradual dip, to sharp dip, to offset of the coal. Lateral changes in the rate of floor elevation dip are often associated with changes in coal thickness, and in underground mines, changes in floor elevation are sometimes associated with roof falls and haulage problems. In order to test if coal thickness changes within floor depressions were associated with changes in palynology, petrography and coal quality, the coal was sampled at a surface mine across a broad. ramp-like depression that showed down-dip coal thickening. Increment samples of coal from a thick (150 cm), down-ramp and thinner (127 cm), up-ramp position at one surface mine correlate well between sample sites (a distance of 60 m) except for a single increment. The anomalous increment (31 cm) in the lower-middle part of the thick coal bed contained 20% more Lycospora orbicula spores. The rolling floor elevations noted in the study mines are inferred to have been formed as a result of pre-peat paleotopographic depressions, syn-depositional faulting, fault-controlled pre-peat paleotopography, and from compaction beneath post-depositional channels and slumps. Although the association of thick coal with linear trends and inferred faults has been used in other basins to infer syn-depositional faulting, changes in palynology within increment samples of the seam along a structural ramp in this study provide subtle evidence of faulting within a specific increment of the coal itself. The sudden increase in L. orbicula (produced by Paralycopodites) in a single increment of a down-ramp sample of the Western Kentucky No. 4 coal records the reestablishment of a rheotrophic mire following a sudden change in edaphic conditions. Paralycopodites was a colonizing lycopod, which in this case became locally abundant after the peat was well established along a fault with obvious growth during peat accumulation. Because many coal-mire plants were susceptible to sudden edaphic changes as might accompany faulting or flooding, changes in palynology would be expected in coals affected by syn-depositional faulting. ?? 2001 Elsevier Science B.V. All rights reserved.

Hydrologic investigation and remediation of a post-remining acidic seep

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aljoe, W.W.; Linberg, N.A.

1996-12-31

Surface remining of coal pillars in abandoned underground workings in the Pittsburgh seam in southwestern Pennsylvania has often resulted in post-remining discharges whose water quality is the same or better than the pre-existing discharges. However, at one such operation in Washington County, PA, an increase in contaminant loading occurred at an outcrop seep after remining. This problem was believed to be at least partly related to a small unstrapped area of the old deep mine workings immediately upgradient from the seep. A hydrologic investigation that included a chemical tracer test, slug tests in the remined spoil, and water quality monitoringmore » indicated that the mine pool in the old workings discharged through the seep. However, the water in the mine pool and much of the remined spoil was consistently alkaline; this suggested that the acidic water may have originated in other areas of the spoil and old workings, and passed rapidly to the seep through a highly transmissive portion of the spoil. Acting on this assumption, the mine operator successfully implemented a remediation scheme in which the spoil was excavated to intercept the acidic spoil water. The excavation was then re-emplaced with an anoxic limestone drain at its base. The drain now serves both to add alkalinity to the water and to divert the seep to an area where metals can be removed easily via precipitation in wetlands.« less

Beam/seam alignment control for electron beam welding

DOEpatents

Burkhardt, Jr., James H.; Henry, J. James; Davenport, Clyde M.

1980-01-01

This invention relates to a dynamic beam/seam alignment control system for electron beam welds utilizing video apparatus. The system includes automatic control of workpiece illumination, near infrared illumination of the workpiece to limit the range of illumination and camera sensitivity adjustment, curve fitting of seam position data to obtain an accurate measure of beam/seam alignment, and automatic beam detection and calculation of the threshold beam level from the peak beam level of the preceding video line to locate the beam or seam edges.

Coal Field Fire Fighting - Practiced methods, strategies and tactics

NASA Astrophysics Data System (ADS)

Wündrich, T.; Korten, A. A.; Barth, U. H.

2009-04-01

Subsurface coal fires destroy millions of tons of coal each year, have an immense impact to the ecological surrounding and threaten further coal reservoirs. Due to enormous dimensions a coal seam fire can develop, high operational expenses are needed. As part of the Sino-German coal fire research initiative "Innovative technologies for exploration, extinction and monitoring of coal fires in Northern China" the research team of University of Wuppertal (BUW) focuses on fire extinction strategies and tactics as well as aspects of environmental and health safety. Besides the choice and the correct application of different extinction techniques further factors are essential for the successful extinction. Appropriate tactics, well trained and protected personnel and the choice of the best fitting extinguishing agents are necessary for the successful extinction of a coal seam fire. The chosen strategy for an extinction campaign is generally determined by urgency and importance. It may depend on national objectives and concepts of coal conservation, on environmental protection (e.g. commitment to green house gases (GHG) reductions), national funding and resources for fire fighting (e.g. personnel, infrastructure, vehicles, water pipelines); and computer-aided models and simulations of coal fire development from self ignition to extinction. In order to devise an optimal fire fighting strategy, "aims of protection" have to be defined in a first step. These may be: - directly affected coal seams; - neighboring seams and coalfields; - GHG emissions into the atmosphere; - Returns on investments (costs of fire fighting compared to value of saved coal). In a further step, it is imperative to decide whether the budget shall define the results, or the results define the budget; i.e. whether there are fixed objectives for the mission that will dictate the overall budget, or whether the limited resources available shall set the scope within which the best possible results shall be achieved. For an effective and efficient fire fighting optimal tactics are requiered and can be divided into four fundamental tactics to control fire hazards: - Defense (digging away the coal, so that the coal can not begin to burn; or forming a barrier, so that the fire can not reach the not burning coal), - Rescue the coal (coal mining of a not burning seam), - Attack (active and direct cooling of burning seam), - Retreat (only monitoring till self-extinction of a burning seam). The last one is used when a fire exceeds the organizational and/or technical scope of a mission. In other words, "to control a coal fire" does not automatically and in all situations mean "to extinguish a coal fire". Best-practice tactics or a combination of them can be selected for control of a particular coal fire. For the extinguishing works different extinguishing agents are available. They can be applied by different application techniques and varying distinctive operating expenses. One application method may be the drilling of boreholes from the surface or covering the surface with low permeability soils. The mainly used extinction agents for coal field fire are as followed: Water (with or without additives), Slurry, Foaming mud/slurry, Inert gases, Dry chemicals and materials and Cryogenic agents. Because of its tremendous dimension and its complexity the worldwide challenge of coal fires is absolutely unique - it can only be solved with functional application methods, best fitting strategies and tactics, organisation and research as well as the dedication of the involved fire fighters, who work under extreme individual risks on the burning coal fields.

Coal reserves and resources as well as potentials for underground coal gasification in connection with carbon capture and storage (CCS)

NASA Astrophysics Data System (ADS)

Ilse, Jürgen

2010-05-01

Coal is the energy source with the largest geological availability worldwide. Of all non-renewable energies coal and lignite accounting for 55 % of the reserves and some 76 % of the resources represent the largest potential. Reserves are those geological quantities of a mineral which can currently be mined under technically and economically viable conditions. Resources are those quantities which are either proven but currently not economically recoverable or quantities which can still be expected or explored on the basis of geological findings. The global availability of energy source does not only depend on geological and economic factors. The technical availability, e.g. mining and preparation capacities, the sufficient availability of land and sea-borne transportation as well as transloading capacities and also a political availability are required likewise. The latter may be disturbed by domestic-policy disputes like strikes or unrest or by foreign-policy disputes like embargos, trade conflicts or even tensions and wars in the producing regions. In the energy-economic discussion the reach of fossil primary energies plays a central role with the most important questions being: when will which energy source be exhausted, which impact will future developments have on the energy price, what does the situation of the other energies look like and which alternatives are there? The reach of coal can only be estimated because of the large deposits on the one hand and the uncertain future coal use and demand on the other. The stronger growth of population and the economic catching-up process in the developing and threshold countries will result in a shift of the production and demand centres in the global economy. However, also in case of further increases the geological potential will be sufficient to reliably cover the global coal demand for the next 100 years. The conventional mining of seams at great depths or of thin seams reaches its technical and economic limits. However, these otherwise unprofitable coal deposits can be mined economically by means of underground coal gasification, during which coal is converted into a gaseous product in the deposit. The synthesis gas can be used for electricity generation, as chemical base material or for the production of petrol. This increases the usability of coal resources tremendously. At present the CCS technologies (carbon capture and storage) are a much discussed alternative to other CO2 abatement techniques like efficiency impovements. The capture and subsequent storage of CO2 in the deposits created by the actual underground gasification process seem to be technically feasible.

Additional Samples: Where They Should Be Located

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pilger, G. G., E-mail: jfelipe@ufrgs.br; Costa, J. F. C. L.; Koppe, J. C.

2001-09-15

Information for mine planning requires to be close spaced, if compared to the grid used for exploration and resource assessment. The additional samples collected during quasimining usually are located in the same pattern of the original diamond drillholes net but closer spaced. This procedure is not the best in mathematical sense for selecting a location. The impact of an additional information to reduce the uncertainty about the parameter been modeled is not the same everywhere within the deposit. Some locations are more sensitive in reducing the local and global uncertainty than others. This study introduces a methodology to select additionalmore » sample locations based on stochastic simulation. The procedure takes into account data variability and their spatial location. Multiple equally probable models representing a geological attribute are generated via geostatistical simulation. These models share basically the same histogram and the same variogram obtained from the original data set. At each block belonging to the model a value is obtained from the n simulations and their combination allows one to access local variability. Variability is measured using an uncertainty index proposed. This index was used to map zones of high variability. A value extracted from a given simulation is added to the original data set from a zone identified as erratic in the previous maps. The process of adding samples and simulation is repeated and the benefit of the additional sample is evaluated. The benefit in terms of uncertainty reduction is measure locally and globally. The procedure showed to be robust and theoretically sound, mapping zones where the additional information is most beneficial. A case study in a coal mine using coal seam thickness illustrates the method.« less

Determination of the Zone Endangered by Methane Explosion in Goaf with Caving of Longwalls Ventilated on "Y" System

NASA Astrophysics Data System (ADS)

Brodny, Jarosław; Tutak, Magdalena

2016-12-01

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 occurrence of initials (e.g. spark or endogenous fire), it may come to the explosion of this gas. In the paper there are presented 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 heading 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 necessary 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 successfully used for the analysis of variants of processes related to ventilation of underground mining, and also in the analysis of emergency states.

Long Term Monitoring of Ground Motions in Upper Silesia Coal Basin (USCB) Using Satellite Radar Interferometry

NASA Astrophysics Data System (ADS)

Graniczny, Marek; Przylucka, Maria; Kowalski, Zbigniew

2016-08-01

Subsidence hazard and risk within the USCB are usually connected with the deep coal mining. In such cases, the surface becomes pitted with numerous collapse cavities or basins which depth may even reach tens of meters. The subsidence is particularly dangerous because of causing severe damage to gas and water pipelines, electric cables, and to sewage disposal systems. The PGI has performed various analysis of InSAR data in this area, including all three SAR bands (X, C and L) processed by DInSAR, PSInSAR and SqueeSAR techniques. These analyses of both conventional and advanced DInSAR approaches have proven to be effective to detect the extent and the magnitude of mining subsidence impact on urban areas. In this study an analysis of two series of subsequent differential interferograms obtained in the DInSAR technique are presented. SAR scenes are covering two periods and were acquired by two different satellites: ALOS-P ALSAR data from 22/02/2007- 27/05/2008 and TerraSAR-X data from 05/07/2011-21/06/2012. The analysis included determination of the direction and development of subsidence movement in relation to the mining front and statistic comparison between range and value of maximum subsidence detected for each mining area. Detailed studies were performed for Bobrek-Centrum mining area. They included comparison of mining fronts and location of the extracted coal seams with the observed subsidence on ALOS-P ALSAR InSAR interferograms. The data can help in estimation not only the range of the subsidence events, but also its value, direction of changes and character of the motion.

Coalbed methane: Clean energy for the world

USGS Publications Warehouse

Ahmed, A.-J.; Johnston, S.; Boyer, C.; Lambert, S.W.; Bustos, O.A.; Pashin, J.C.; Wray, A.

2009-01-01

Coalbed methane (CBM) has the potential to emerge as a significant clean energy resource. It also has the potential to replace other diminishing hydrocarbon reserves. The latest developments in technologies and methodologies are playing a key role in harnessing this unconventional resource. Some of these developments include adaptations of existing technologies used in conventional oil and gas generations, while others include new applications designed specifically to address coal's unique properties. Completion techniques have been developed that cause less damage to the production mechanisms of coal seams, such as those occurring during cementing operations. Stimulation fluids have also been engineered specifically to enhance CBM production. Deep coal deposits that remain inaccessible by conventional mining operations offer CBM development opportunities.

Environmental implications of material leached from coal.

PubMed

Moyo, Stanley; Mujuru, Munyaradzi; McCrindle, Rob I; Mokgalaka-Matlala, Ntebogeng

2011-05-01

Samples of coal were collected from different seams at a South African coal mine and comparative leaching experiments were carried out under various pH conditions and times to investigate the leaching behavior and potential environmental impact of possibly hazardous elements such as As, Cd, Co, Cr, Mn, Ni, Pb, Th and U. The calculated leaching intensities, sequential extraction results and cumulative percentages demonstrate that the leaching behavior of the elements is strongly influenced by the pH, the leaching time and the properties and occurrences of the elements. The leached concentrations of As, Cd, Co, Cr, Mn, Ni and Pb exceeded the maximum concentrations recommended by the Environmental Protection Agency (EPA) for surface water.

Yesterday's forest, tomorrow's savannah? Legacies in the man-made hills of Appalachia

NASA Astrophysics Data System (ADS)

Ross, M. R. V.; Nippgen, F.; McGlynn, B. L.; Bernhardt, E. S.

2017-12-01

Mountaintop removal coal mines have converted more than 6,000 km2 of the steep forested valleys of Central Appalachian into a landscape of rolling hills covered by shrubby grasslands. These landscapes were created as a byproduct of extracting shallow coal seams from beneath hundreds of meters of overlying bedrock. Once broken apart by explosives, this excess rock overburden is deposited into valley fills and incorporated into reconstructed ridges. The landscapes left behind after mining are flattened and overlies highly fractured fill material that can be 100-fold deeper than natural soil. This fractured bedrock material can store 2-10 years worth of average precipitation, where any stored water is in contact with a reactive mix of unweathered carbonate bedrock and pyrite rich coal and shale residues. As a result, mountaintop mined watersheds have novel hydrologic and biogeochemical regimes with increases in baseflow and extremely rapid weathering that increases salinity by 10-25-fold. To date, little research has characterized the longevity of these impacts. We employed a combination of remote sensing and hydrologic watershed monitoring approaches to examine the long-term and linked changes in vegetation, hydrology, and water quality in a post-mine landscapes that were constructed between 1990 and 2016. We find that forest recovery on mountaintop mines progresses at half the rate of forest regrowth following clearcutting with persistent low canopy-height sections, consistent more with grasslands than forests. These vegetative changes are associated with decreases in runoff ratios as mines age and water moves through flatter, vegetated landscapes. However, vegetation change appears to be uncoupled from biogeochemical processes, with saline mine drainage persisting for decades, even as vegetation regrows. Our work suggests that time-since-mining of a watershed does not predict downstream water quality, while total valley fill volume remains a strong predictor of mean salinity and total weathering rates. This research highlights the importance of understanding how deep changes to a landscape alters the basic hydrology and biogeochemistry over years to decades.

The C. elegans engrailed homolog ceh-16 regulates the self-renewal expansion division of stem cell-like seam cells.

PubMed

Huang, Xinxin; Tian, E; Xu, Yanhua; Zhang, Hong

2009-09-15

Stem cells undergo symmetric and asymmetric division to maintain the dynamic equilibrium of the stem cell pool and also to generate a variety of differentiated cells. The homeostatic mechanism controlling the choice between self-renewal and differentiation of stem cells is poorly understood. We show here that ceh-16, encoding the C. elegans ortholog of the transcription factor Engrailed, controls symmetric and asymmetric division of stem cell-like seam cells. Loss of function of ceh-16 causes certain seam cells, which normally undergo symmetric self-renewal expansion division with both daughters adopting the seam cell fate, to divide asymmetrically with only one daughter retaining the seam cell fate. The human engrailed homolog En2 functionally substitutes the role of ceh-16 in promoting self-renewal expansion division of seam cells. Loss of function of apr-1, encoding the C. elegans homolog of the Wnt signaling component APC, results in transformation of self-renewal maintenance seam cell division to self-renewal expansion division, leading to seam cell hyperplasia. The apr-1 mutation suppresses the seam cell division defect in ceh-16 mutants. Our study reveals that ceh-16 interacts with the Wnt signaling pathway to control the choice between self-renewal expansion and maintenance division and also demonstrates an evolutionarily conserved function of engrailed in promoting cell proliferation.

Publications - GMC 278 | Alaska Division of Geological & Geophysical

Science.gov Websites

DGGS GMC 278 Publication Details Title: High pressure methane adsorption analyses for coal samples of the Matanuska Valley coal-bed methane AK 94-CBM-1 hole as follows: Seam #1, Seam #6, Seam #9, and Seam , High pressure methane adsorption analyses for coal samples of the Matanuska Valley coal-bed methane AK

Feasibility of high recovery highwall mining equipment. Final report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1981-01-01

Three equipment systems exhibited significant promise: the RSV Miner, a surface longwall using standard underground equipment, and the variable angle auger. Other equipment systems showing considerable merit were the surface shortwall, and the two extended depth augers. Of the three most significant systems, the RSV Miner exhibits the greatest versatility and adaptability. It may be used competently in many surface mining applications and readily adapts to geologic anomalies and changing seam heights. The machine employs steering and guidance equipment and provides the necessary capabilities for extended depth operation. Safety is good, as no men are required to work underground. However,more » most important is the system's recovery factor of approximately 75% to 80% of the in-situ coal reserve within reach. The surface longwall system using standard underground equipment (preferably a ranging drum shearer in conjunction with shield supports) is most suited to either a trench mining or a modified area mining application. Both applications would allow the length of the face to be held constant. Another important consideration is legal requirements for a tailgate entry, which would necessitate additional equipment for development in a modified area mining application. When compared to surface shortwall, surface longwall exhibits higher productivity, a far greater equipment selection which allows system tailoring to geologic conditions, and greater roof control due to the significantly smaller section of overburden that must be supported. Recovery should approach, and possibly exceed, 90% of the coal in-place. The variable angle auger, which is currently only a concept, fills a very real need for which no other equipment is available at this time.« less

A Unified Framework for Street-View Panorama Stitching

PubMed Central

Li, Li; Yao, Jian; Xie, Renping; Xia, Menghan; Zhang, Wei

2016-01-01

In this paper, we propose a unified framework to generate a pleasant and high-quality street-view panorama by stitching multiple panoramic images captured from the cameras mounted on the mobile platform. Our proposed framework is comprised of four major steps: image warping, color correction, optimal seam line detection and image blending. Since the input images are captured without a precisely common projection center from the scenes with the depth differences with respect to the cameras to different extents, such images cannot be precisely aligned in geometry. Therefore, an efficient image warping method based on the dense optical flow field is proposed to greatly suppress the influence of large geometric misalignment at first. Then, to lessen the influence of photometric inconsistencies caused by the illumination variations and different exposure settings, we propose an efficient color correction algorithm via matching extreme points of histograms to greatly decrease color differences between warped images. After that, the optimal seam lines between adjacent input images are detected via the graph cut energy minimization framework. At last, the Laplacian pyramid blending algorithm is applied to further eliminate the stitching artifacts along the optimal seam lines. Experimental results on a large set of challenging street-view panoramic images captured form the real world illustrate that the proposed system is capable of creating high-quality panoramas. PMID:28025481

Novel approach for extinguishing large-scale coal fires using gas-liquid foams in open pit mines.

PubMed

Lu, Xinxiao; Wang, Deming; Qin, Botao; Tian, Fuchao; Shi, Guangyi; Dong, Shuaijun

2015-12-01

Coal fires are a serious threat to the workers' security and safe production in open pit mines. The coal fire source is hidden and innumerable, and the large-area cavity is prevalent in the coal seam after the coal burned, causing the conventional extinguishment technology difficult to work. Foams are considered as an efficient means of fire extinguishment in these large-scale workplaces. A noble foam preparation method is introduced, and an original design of cavitation jet device is proposed to add foaming agent stably. The jet cavitation occurs when the water flow rate and pressure ratio reach specified values. Through self-building foaming system, the high performance foams are produced and then infused into the blast drilling holes at a large flow. Without complicated operation, this system is found to be very suitable for extinguishing large-scale coal fires. Field application shows that foam generation adopting the proposed key technology makes a good fire extinguishment effect. The temperature reduction using foams is 6-7 times higher than water, and CO concentration is reduced from 9.43 to 0.092‰ in the drilling hole. The coal fires are controlled successfully in open pit mines, ensuring the normal production as well as the security of personnel and equipment.

Energy generation potential from coals of the Charqueadas Coalfield, RS, Brazil

NASA Astrophysics Data System (ADS)

Correa da Silva, Z. C.; Heemann, R.; Castro, L.; Ketzer, J. M.

2009-04-01

Three coal seams, I2B (Inferior 2), I1F (Inferior 1) and MB, from the Charqueadas Coalfield located in the central-east region of the State of Rio Grande do Sul, Southern Brazil were studied on the basis of geological, petrographic, chemical and geochemical techniques and correlated to the SR1, SR2 and SR3 coal seams from the Santa Rita Coalfield. The Charqueadas Coalfield reserves reach 2,993x106 metric tons of coal distributed in six coal seams. The study of sedimentary and organic facies is made on the subsurface data from five boreholes drilled in the area. There show a well marked lateral facies change from sub aquatic to sub aerial environment, conditioned by both the water level variations and the irregular palaeotopography of the basement. The coals change from limnic to forest-terrestrial moor types characterized by variations of composition in terms of macerals, microlithotypes and mineral matter. The coals are rich in mineral matter (28 to 40%); the vitrinite content reaches 50 %, inertinite 44 % and liptinite varies from 10 to 30 %, in mineral matter free basis. Among the microlithotypes carbominerite and vitrite are predominant. Rank studies carried out by different methods (vitrinite reflectance, max and red-green quotient among others) gave conflicting results, which are explained by the strong bituminization of the vitrinite. However, agreement between fluorescence measurements and organic geochemical parameters (e.g. CPI values) confirm that the coals are of a High Volatile Bituminous B/C (ASTM) or Gasflammkohle (DIN) rank. Based on these characteristics, the Charqueadas coal seams show great potential for use in Underground Coal Gasification (UCG) and Enhanced Coalbed Methane (ECBM) projects. Nowadays the state of Rio Grande do Sul is rapidly growing and needs to increase the energy efficiency to attend the industrial demands, filling the gap between supply and energy generation. As with conventional IGCC, UCG gas can be used to generate electricity with efficiency as high as 55% and overall UCG-IGCC process efficiency reaching 43%. Regarding to environmental problems the UCG minimize environmental impacts (waste piles/acid mine drainage) and reduce CO2 emissions because syngas contains CO2 that can be captured with relatively low-energy penalty. The Clean Coal Technologies (CCT), especially UCG and ECBM projects, will be a key factor to maintain the annual state's economy expansion associated with energy efficiency improvement programs.

Deconstructing the deconstruction of Appalachia: Mountaintop mining effects on hydrology across temporal and spatial scales

NASA Astrophysics Data System (ADS)

Nippgen, F.; Ross, M. R. V.; Bernhardt, E. S.; McGlynn, B. L.

2017-12-01

Mountaintop mining (MTM) is an especially destructive form of surface coal mining. It is widespread in Central Appalachia and is practiced around the world. In the process of accessing coal seams up to several hundred meters below the surface, mountaintops and ridges are removed via explosives and heavy machinery with the resulting overburden pushed into nearby valleys. This broken up rock and soil material represents a largely unknown amount of storage for incoming precipitation that facilitates enhanced chemical weathering rates and increased dissolved solids exports to streams. However, assessing the independent impact of MTM can be difficult in the presence of other forms of mining, especially underground mining. Here, we evaluate the effect of MTM on water quantity and quality on annual, seasonal, and event time scales in two sets of paired watersheds in southwestern West Virginia impacted by MTM. On an annual timescale, the mined watersheds sustained baseflow throughout the year, while the first order watersheds ceased flowing during the latter parts of the growing season. In fractionally mined watersheds that continued to flow, the water in the stream was exclusively generated from mined portions of the watersheds, leading to elevated total dissolved solids in the stream water. On the event time scale, we analyzed 50 storm events over a water year for a range of hydrologic response metrics. The mined watersheds exhibited smaller runoff ratios and longer response times during the wet dormant season, but responded similarly to rainfall events during the growing season or even exceeded the runoff magnitude of the reference watersheds. Our research demonstrates a clear difference in hydrologic response between mined and unmined watersheds during the growing season and the dormant season that are detectable at annual, seasonal, and event time scales. For larger spatial scales (up to 2,000km2) the effect of MTM on water quantity is not as easily detectable. At these larger scales, other land uses can mask possible alterations in hydrology or the percentage of MTM disturbed areas becomes negligible.

Investigation of Intrinsic and External Factors Contributing to the Occurrence of Coal Bumps in the Mining Area of Western Beijing, China

NASA Astrophysics Data System (ADS)

Wang, Hongwei; Jiang, Yaodong; Xue, Sheng; Pang, Xufeng; Lin, Zhinan; Deng, Daixin

2017-04-01

An investigation has been made to relate the occurrence of coal bumps to specific geological and mining conditions to the mining area of western Beijing. This investigation demonstrates that the high frequency of coal bumps in this area is due to four localized conditions, namely intrinsic coal properties, the presence of overturned strata and thrust faults, high in situ stress and the extraction of coal from island mining faces. Laboratory tests of coal samples indicated that the coals have a short duration of dynamic fracture, high bursting energy and high elastic strain energy, indicating that the coal is intrinsically prone to the occurrence of coal bumps. This investigation has also revealed that there are overturned strata and well-developed large- and medium-scale thrust faults in this area, and the presence of these structures results in plastic flow, severe discontinuities, rapid changes in overburden thickness and dipping of the coal seams. Well-developed secondary fold structures are also present in the axes and limbs of the primary folds. The instability of thrust faults, in combination with large-scale intrusion of igneous rocks, is closely associated with sudden roof breaking and induces sharp variations in electromagnetic radiation (EMR) and micro-seismic signals, which could be used to help predict coal bumps. In situ stress tests in the mining area demonstrate that the maximum and minimum principal stresses are nearly horizontal and that the intermediate principal stress is approximately vertical. The in situ stress level in the area is higher than the average in the Beijing area, North China and mainland China. In addition to the presence of overturned strata and thrust faults and high in situ stress levels, another external factor contributing to the frequency of coal bumps is coal extraction from island mining faces in this area. Island mining faces experience intermittent mining-induced abutment stress when a fault exists at one side of the island mining face due to reactivation of the fault, and this stress redistribution increases the likelihood of coal bumps during coal extraction from island mining faces.

Evaluation of bending rigidity behaviour of ultrasonic seaming on woven fabrics

NASA Astrophysics Data System (ADS)

Şevkan Macit, Ayşe; Tiber, Bahar

2017-10-01

In recent years ultrasonic seaming that is shown as an alternative method to conventional seaming has been investigated by many researchers. In our study, bending behaviour of this alternative method is examined by changing various parameters such as fabric type, seam type, roller type and seaming velocity. For this purpose fifteen types of sewn fabrics were tested according to bending rigidity test standard before and after washing processes and results were evaluated through SPSS statistical analyze programme. Consequently, bending length values of the ultrasonically sewn fabrics are found to be higher than the bending length values of conventionally sewn fabrics and the effects of seam type on bending length are seen statistically significant. Also it is observed that bending length values are in relationship with the rest of the parameters excluding roller type.

Pressure solution and microfracturing in primary oil migration, Upper Cretaceous Austin Chalk, Texas Gulf Coast

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chanchani, J.; Berg, R.R.; Lee, C.I.

1996-09-01

The Upper Cretaceous Austin Chalk is a well known source rock and fractured reservoir in the Gulf Coast. Production is mainly from tectonic fractures, and the mechanism by which oil migrated from the matrix into the fractures is poorly understood. Microfracturing due to oil generation offers a possible explanation for the mechanism of the primary migration of oil in the Austin Chalk. Petrographic study shows that the major components of the primary migration system are the solution seams and the associated microfractures. Pressure solution is manifest as centimeter to millimeter-scale solution seams and smaller microseams. The solution seams are compositesmore » formed by the superposition of the smaller microseams. A significant amount of organic matter was concentrated in the seams along with other insoluble residue. Swarms of horizontal microfractures, many of them filled with calcite and other residue, are associated with the seams. Vertical, tectonic fractures that constitute the reservoir porosity, intersect the solution seams. Pressure solution concentrated organic matter within the solution seams and oil was generated there. It is postulated that the accompanying increase in fluid volume raised the pore pressures and fractured the rock. The newly created microfractures were avenues for migration of fluids from the seams, perhaps by microfracture propagation.« less

From in situ coal to the final coal product: A case study of the Danville Coal Member (Indiana)

USGS Publications Warehouse

Mastalerz, Maria; Padgett, P.L.

1999-01-01

A surface coal mine operation and preparation plant in southwestern Indiana was sampled to examine variations in coal quality and coal petrography parameters for the Danville Coal Member of the Dugger Formation (Pennsylvanian-Desmoinesian, Westphalian D). Representative samples from in situ coal, preparation plant feeds, and a final coal product were collected in order to compare coal quality, coal petrography, trace element concentrations, and ash chemistry of the coal to those of the product. Coal quality parameters of the in situ samples and various feeds, coarse refuse, and final product were variable. The quality of the final coal product was best predicted by the coal quality of the clean coal feed (from the middle portions of the seam). Some trace element contents, especially lead and arsenic, varied between the coal feeds and the product. Lead contents increased in the feeds and product compared to the channel sample of the raw coal, possibly due to contamination in the handling process.A surface coal mine operation and preparation plant in southwestern Indiana was sampled to examine variations in coal quality and coal petrography parameters for the Danville Coal Member of the Dugger Formation (Pennsylvanian-Desmoinesian, Westphalian D). Representative samples from in situ coal, preparation plant feeds, and a final coal product were collected in order to compare coal quality, coal petrography, trace element concentrations, and ash chemistry of the coal to those of the product. Coal quality parameters of the in situ samples and various feeds, coarse refuse, and final product were variable. The quality of the final coal product was best predicted by the coal quality of the clean coal feed (from the middle portions of the seam). Some trace element contents, especially lead and arsenic, varied between the coal feeds and the product. Lead contents increased in the feeds and product compared to the channel sample of the raw coal, possibly due to contamination in the handling process.

A new optimal seam method for seamless image stitching

NASA Astrophysics Data System (ADS)

Xue, Jiale; Chen, Shengyong; Cheng, Xu; Han, Ying; Zhao, Meng

2017-07-01

A novel optimal seam method which aims to stitch those images with overlapping area more seamlessly has been propos ed. Considering the traditional gradient domain optimal seam method and fusion algorithm result in bad color difference measurement and taking a long time respectively, the input images would be converted to HSV space and a new energy function is designed to seek optimal stitching path. To smooth the optimal stitching path, a simplified pixel correction and weighted average method are utilized individually. The proposed methods exhibit performance in eliminating the stitching seam compared with the traditional gradient optimal seam and high efficiency with multi-band blending algorithm.

Water-quality data for two surface coal mines reclaimed with alkaline waste or urban sewage sludge, Clarion County, Pennsylvania, May 1983 through November 1989

USGS Publications Warehouse

Dugas, D.L.; Cravotta, C.A.; Saad, D.A.

1993-01-01

Water-quality and other hydrologic data for two surface coal mines in Clarion County, Pa., were collected during 1983-89 as part of studies conducted by the U.S. Geological Survey in cooperation with the Pennsylvania Department of Environmental Resources. Water samples were collected from streams, seeps, monitor wells, and lysimeters on a monthly basis to evaluate changes in water quality resulting from the addition of alkaline waste or urban sewage sludge to the reclaimed mine-spoil surface. The mines are about 3.5 miles apart and were mined for bituminous coal of the upper and lower Clarion seams of the Allegheny Group of Pennsylvanian age. The coal had high sulfur (greater than 2 weight percent) concentrations. Acidic mine drainage is present at both mines. At one mine, about 8 years after mining was completed, large quantities (greater than 400 tons per acre) of alkaline waste consisting of limestone and lime-kiln flue dust were applied on two 2.5-acre plots within the 65-acre mine area. Water-quality data for the alkaline-addition plots and surrounding area were collected for 1 year before and 3 years after application of the alkaline additives (May 1983-July 1987). Data collected for the alkaline-addition study include ground-water level, surface-water discharge rate, temperature, specific conductance, pH, and concentrations of alkalinity, acidity, sulfate, iron (total and ferrous), manganese, aluminum, calcium, and magnesium. At the other mine, about 3.5 years after mining was completed, urban sewage sludge was applied over 60 acres within the 150-acre mine area. Waterquality data for the sludge-addition study were collected for 3.5 years after the application of the sludge (June 1986-December 1989). Data collected for the sludge-addition study include the above constituents plus dissolved oxygen, redox potential (Eh), and concentrations of dissolved solids, phosphorus, nitrogen species, sulfide, chloride, silica, sodium, potassium, cyanide, arsenic, barium, boron, cadmium, chromium, copper, lead, mercury, molybdenum, nickel, selenium, strontium, and zinc. Climatic data, including monthly average temperature and cumulative precipitation, from a nearby weather station for the period January 1983 through December 1989 also are reported.

Combined mining: discovering informative knowledge in complex data.

PubMed

Cao, Longbing; Zhang, Huaifeng; Zhao, Yanchang; Luo, Dan; Zhang, Chengqi

2011-06-01

Enterprise data mining applications often involve complex data such as multiple large heterogeneous data sources, user preferences, and business impact. In such situations, a single method or one-step mining is often limited in discovering informative knowledge. It would also be very time and space consuming, if not impossible, to join relevant large data sources for mining patterns consisting of multiple aspects of information. It is crucial to develop effective approaches for mining patterns combining necessary information from multiple relevant business lines, catering for real business settings and decision-making actions rather than just providing a single line of patterns. The recent years have seen increasing efforts on mining more informative patterns, e.g., integrating frequent pattern mining with classifications to generate frequent pattern-based classifiers. Rather than presenting a specific algorithm, this paper builds on our existing works and proposes combined mining as a general approach to mining for informative patterns combining components from either multiple data sets or multiple features or by multiple methods on demand. We summarize general frameworks, paradigms, and basic processes for multifeature combined mining, multisource combined mining, and multimethod combined mining. Novel types of combined patterns, such as incremental cluster patterns, can result from such frameworks, which cannot be directly produced by the existing methods. A set of real-world case studies has been conducted to test the frameworks, with some of them briefed in this paper. They identify combined patterns for informing government debt prevention and improving government service objectives, which show the flexibility and instantiation capability of combined mining in discovering informative knowledge in complex data.

Isotopic evidence of enhanced carbonate dissolution at a coal mine drainage site in Allegheny County, Pennsylvania, USA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Shikha; Sack, Andrea; Adams, James P.

Stable isotopes were used to determine the sources and fate of dissolved inorganic C (DIC) in the circumneutral pH drainage from an abandoned bituminous coal mine in western Pennsylvania. The C isotope signatures of DIC (δ{sup 13}C{sub DIC}) were intermediate between local carbonate and organic C sources, but were higher than those of contemporaneous Pennsylvanian age groundwaters in the region. This suggests a significant contribution of C enriched in {sup 13}C due to enhanced carbonate dissolution associated with the release of H{sub 2}SO{sub 4} from pyrite oxidation. The Sr isotopic signature of the drainage was similar to other regional minemore » waters associated with the same coal seam and reflected contributions from limestone dissolution and cation exchange with clay minerals. The relatively high δ{sup 34}S{sub SO4} and δ{sup 18}O{sub SO4} isotopic signatures of the mine drainage and the presence of presumptive SO{sub 4}-reducing bacteria suggest that SO{sub 4} reduction activity also contributes C depleted in {sup 13}C isotope to the total DIC pool. With distance downstream from the mine portal, C isotope signatures in the drainage increased, accompanied by decreased total DIC concentrations and increased pH. These data are consistent with H{sub 2}SO{sub 4} dissolution of carbonate rocks, enhanced by cation exchange, and C release to the atmosphere via CO{sub 2} outgassing.« less

Design for Manufacturing and Assembly in Apparel. Part 1. Handbook

DTIC Science & Technology

1994-02-01

reduced and the inverted pleat was eliminated to take advantage of the automatic seam stitcher . The shape and size of the side back section seam...coin pocket. The size and shape of the pocket would be designed to best utilize the equipment. An automatic dart stitcher may be utilized to stitch the...with stacker Semi-automatic serging units with stacker Automatic seaming units/profile stitchers Programmable seaming units for various operations

Responses of terrestrial herpetofauna to persistent, novel ecosystems resulting from mountaintop removal mining

USGS Publications Warehouse

Williams, Jennifer M.; Brown, Donald J.; Wood, Petra B.

2017-01-01

Mountaintop removal mining is a large-scale surface mining technique that removes entire floral and faunal communities, along with soil horizons located above coal seams. In West Virginia, the majority of this mining occurs on forested mountaintops. However, after mining ceases the land is typically reclaimed to grasslands and shrublands, resulting in novel ecosystems. In this study, we examined responses of herpetofauna to these novel ecosystems 10–28 y postreclamation. We quantified differences in species-specific habitat associations, (sub)order-level abundances, and habitat characteristics in four habitat types: reclaimed grassland, reclaimed shrubland, forest fragments in mined areas, and nonmined intact forest. Habitat type accounted for 33.2% of the variation in species-specific captures. With few exceptions, forest specialists were associated with intact forest and fragmented forest sites, while habitat generalists were either associated with grassland and shrubland sites or were distributed among all habitat types. At the (sub)order level, salamander (Order Urodela) captures were highest at fragmented and intact forest sites, frog and toad (Order Anura) captures were lowest at intact forest sites, and snake (Suborder Serpentes) captures were highest at shrubland sites. Habitat type was a strong predictor for estimated total abundance of urodeles, but not for anurans or snakes. Tree stem densities in grasslands differed from the other three habitat types, and large trees (>38 cm diameter at breast height) were only present at forest sites. Overstory vegetation cover was greater in forested than in reclaimed habitat types. Ground cover in reclaimed grasslands was distinct from forest treatments with generally less woody debris and litter cover and more vegetative cover. It is important to consider the distributions of habitat specialists of conservation concern when delineating potential mountaintop mine sites, as these sites will likely contain unsuitable habitat for forest specialists for decades or centuries when reclaimed to grassland or shrubland.

On the development of an underground geoscience laboratory at Boulby in NE England (Invited)

NASA Astrophysics Data System (ADS)

Petley, D. N.; Rosser, N.; Barlow, J.; Brain, M. J.; Lim, M.; Sapsford, M.; Pybus, D.

2009-12-01

The Boulby Mine in NE England is a major potash extraction facility located in NE England. Opened in 1973, the mine extracts both potash and rock salt from Zechstein deposits located at a depth of about 1100 m below the land surface. For the last 20 years the mine has housed an important laboratory built to provide a base for Dark Matter research. However, in the last ten years the mine has progressively become been the site of research into geophysical and geological processes, primarily through a strategic partnership between the mine operators, Cleveland Potash Ltd, and the University of Durham. The site is now the base for an initial proof of concept project, funded by the Regional Development Agency One Northeast, to explore the viability of establishing a permanent geosciences research facility at Boulby. The vision is a facility that provides access for researchers into the range of geological environments at Boulby, extending from the coastal cliffs at the surface, through the access shafts to the deepest potash seams. The facility is designed to host research in geophysics, hydrology, geophysics, geomorphology, geochemistry, microbiology, rock mechanics, mining engineering, petrology and related fields. This proof of concept study has three key strategic aims: 1. To establish the range of uses of a research laboratory at Boulby and to determine the nature of the facilities required; 2. To initiate research programmes into: a. palaeoenvironmental reconstruction of the Zechstein deposits; b. the mechanics of the potash and halite rocks; and c. the mechanisms of failure of the coastal cliffs; 3. To construct an initial four serviced research caverns within the mine. The proof of concept stage of the project is intended to run until September 2010, with development of the facility being completed by 2015. However, the facility is currently in a position to host research projects across a wide range of disciplines.

Ground Penetrating Radar, a Method for Exploration and Monitoring of Coal Fires in China

NASA Astrophysics Data System (ADS)

Gundelach, Volker

2010-05-01

Due to the climate change it is a global task to fight against gas emission of coal fires. In China exists many burning coal seams which should be extinguished. A Chinese-German initiative tries to find new technologies and solutions to control these fires. Most of the fires are close to the surface in arid areas. In that case GPR is a possible geophysical method to get detailed information about the structure of the soil. Mining activities and the burning coal are leaving voids which collapse or still exist as dangerous areas. With GPR it is possible to detect voids and clefts. Crevices are potential paths for oxygen transport from the surface to the fire. The knowledge of these structures would help to extinguish the fire. The heat of the burning coal changes the permittivity and the conductivity of the rock. This affects the radar signal and makes it possible to separate burning zones from intact zones. Monitoring of the burning zones helps to find optimal solutions for fire extinguishing strategies. Several field campaigns were made in China. One campaign was in the province Xinjiang with a 50 MHz system from Mala on a steep dipping coal seam. Other campaigns were in the Inner Mongolia with 40 MHz to 200 MHz antennae from GSSI on shallow dipping coal seams. The experiences from these measurements will be shown. The surveys were collected in rough terrain. The data from the unshielded antennae contained a lot of effects coming through the air. The limits of detecting crevices with GPR will be demonstrated. Some parts of the measurements over burning coal were influenced by strong anomalies of the magnetization. Modeling of the radar signal helps at the interpretation. Parts of the interpretation from the surveys can be validated by the outcrop of the investigated structures. A spatial visualization of the results is the basis for discussions.

Calculation of optimal modes for electric-contact welding of rails of mine haulage tracks

NASA Astrophysics Data System (ADS)

Shevchenko, R. A.; Kozyrev, N. A.; Usoltsev, A. A.; Kriukov, R. E.; Shishkin, P. E.

2017-09-01

The choice of thermal regime is based on the exclusion of formation of quenching structures (martensite and bainite), causing additional stresses and cracks which lead to the destruction of rails. After welded joint upset and cooling at the time of reaching the required temperature it is proposed to perform quasi-isothermal exposure by passing pulses of alternating current through the welded joint. The method for calculating the quasi-isothermal exposure is described that depends on the strength of the welding current and different rails section. It is suggested that after welding the rails during quenching, a quasi-isothermal holding is carried out in the temperature range of the formation of the fine-dispersed structure by passing pulses of alternating electric current through the welded joint maintaining this temperature until the end of the transformation. It is shown that the use of quasi-isothermal exposure at a chosen temperature of 600 - 650 °C makes it possible to obtain a finely dispersed structure of the welded seam of rails of mine haulage tracks without additional heat treatment.

Health concerns associated with unconventional gas mining in rural Australia.

PubMed

Haswell, Melissa R; Bethmont, Anna

2016-01-01

Many governments globally are investigating the benefits and risks associated with unconventional gas mining for shale, tight and coal seam gas (coalbed methane) to determine whether the industry should proceed in their jurisdiction. Most locations likely to be developed are in rural areas, with potential impact on farmers and small communities. Despite significant health concerns, public health knowledge and growing evidence are often overlooked in decision-making. It is difficult to gain a broad but accurate understanding of the health concerns for rural communities because the evidence has grown very recently and rapidly, is complex and largely based in the USA, where the industry is advanced. In 2016, a concerned South Australian beef and lamb farmer in an area targeted for potential unconventional gas development organised visits to homes in developed unconventional gas areas of Pennsylvania and forums with leading researchers and lawyers in Pennsylvania and New York. Guided by priorities identified during this trip, this communication concisely distils the research evidence on these key concerns, highlighting the Australian situation where evidence exists. It summarises key information of particular concern to rural regions, using Australia as an example, to assist rural health professionals to be better prepared to engage in decision-making and address the challenges associated with this new industry. Discussions with communities and experts, supported by the expanding research from the USA and Australia, revealed increasing health concerns in six key areas. These are absence of a safe solution to the toxic wastewater management problems, air pollution, land and water competition, mental health and psychosocial wellbeing risks, fugitive methane emissions and lack of proven regulatory regimes. Emerging epidemiological studies suggesting interference with foetal development and birth outcomes, and exacerbation of asthma conditions, are particularly concerning to rural families and livestock. Rural residents in potentially affected areas should be supported to access and interpret the best current evidence regarding the multiple health concerns associated with unconventional gas mining. This knowledge should be part of wider discourse and decision-making processes driving local economic development and national and global energy choices.

Predicting temporal changes in total iron concentrations in groundwaters flowing from abandoned deep mines: a first approximation

NASA Astrophysics Data System (ADS)

Younger, Paul L.

2000-06-01

Discharges of contaminated groundwater from abandoned deep mines are a major environmental problem in many parts of the world. While process-based models of pollutant generation have been successfully developed for certain surface mines and waste rock piles of relatively simple geometry and limited areal extent, such models are not readily applicable to large systems of laterally extensive, interconnected, abandoned deep mines. As a first approximation for such systems, hydrological and lithological factors, which can reasonably be expected to influence pollutant release, have been assessed by empirically assessing data from 81 abandoned deep coal mine discharges in the UK. These data demonstrate that after flooding of a deep mine is complete and groundwater begins to migrate from the mine voids into surface waters or adjoining aquifers, flushing of the mine voids by fresh recharge results in a gradual improvement in the quality of groundwater (principally manifested as decreasing Fe concentrations and stabilisation of pH around 7). Alternative representations of the flushing process have been examined. While elegant analytical solutions of the advection-dispersion equation can be made to mimic the changes in iron concentration, parameterisation is tendentious in practice. Scrutiny of the UK data suggest that to a first approximation, the duration of the main period of flushing can be predicted to endure around four times as long as the foregoing process of mine flooding. Short- and long-term iron concentrations (i.e. at the start of the main period of flushing and after its completion, respectively) can be estimated from the sulphur content of the worked strata. If strata composition data are unavailable, some indication of pollution potential can be obtained from considerations of the proximity of worked strata to marine beds (which typically have high pyrite contents). The long-term concentrations of iron in a particular discharge can also be approximated on the basis of the proximity of the discharge location to the outcrop of the most closely associated coal seam (MCACS) and, thus, to zones of possible ongoing pyrite oxidation. The practical application of these simple predictive techniques is facilitated by means of a flowchart.

Automated Solvent Seaming of Large Polyimide Membranes

NASA Technical Reports Server (NTRS)

Rood, Robert; Moore, James D.; Talley, Chris; Gierow, Paul A.

2006-01-01

A solvent-based welding process enables the joining of precise, cast polyimide membranes at their edges to form larger precise membranes. The process creates a homogeneous, optical-quality seam between abutting membranes, with no overlap and with only a very localized area of figure disturbance. The seam retains 90 percent of the strength of the parent material. The process was developed for original use in the fabrication of wide-aperture membrane optics, with areal densities of less than 1 kg/m2, for lightweight telescopes, solar concentrators, antennas, and the like to be deployed in outer space. The process is just as well applicable to the fabrication of large precise polyimide membranes for flat or inflatable solar concentrators and antenna reflectors for terrestrial applications. The process is applicable to cast membranes made of CP1 (or equivalent) polyimide. The process begins with the precise fitting together and fixturing of two membrane segments. The seam is formed by applying a metered amount of a doped solution of the same polyimide along the abutting edges of the membrane segments. After the solution has been applied, the fixtured films are allowed to dry and are then cured by convective heating. The weld material is the same as the parent material, so that what is formed is a homogeneous, strong joint that is almost indistinguishable from the parent material. The success of the process is highly dependent on formulation of the seaming solution from the correct proportion of the polyimide in a suitable solvent. In addition, the formation of reliable seams depends on the deposition of a precise amount of the seaming solution along the seam line. To ensure the required precision, deposition is performed by use of an automated apparatus comprising a modified commercially available, large-format, ink-jet print head on an automated positioning table. The printing head jets the seaming solution into the seam area at a rate controlled in coordination with the movement of the positioning table.

Assessment of the Influence of Fractures on the Dynamics of Coal Seam Fires by Numerical Experiments

NASA Astrophysics Data System (ADS)

Wuttke, Manfred W.; Zeng, Qiang

2016-04-01

Uncontrolled burning coal seam fires still constitute major problems for the coal industry by destroying the resource, a serious hazard for the local people by severe environmental pollution, and a tremendous threat to the global environment by the emission of greenhouse gases and aerosols. In particular when the seams are lying shallow the alteration of the immediate surrounding of the coal seam fire feeds back on the dynamics of the fire. Thermal stress induced fracturing produces direct connections of the fire zone with the atmosphere. This influences the supply with oxygen, the venting of the exhaust gases, and the dissipation of heat. The first two processes are expected to enhance the fire propagation whereas the latter effect should slow it down. With our dedicated coal seam fire code ACME ("Amendable Coal-fire Modeling Exercise") we study these coupled effects of fractures in simulations of typical coal seam fire scenarios based on data from Xinjiang, China. Fractures are predefined as 1D/2D objects in a 2D/3D model geometry and are opened depending on the passage of the heat wave produced by the coal seam fire.

Automated flotation control at Jim Walter Resources, Mining Division

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burchfield, J.W.

1993-12-31

Jim Walter Resources (JWR), Mining Division, operates in west-central Alabama in Jefferson and Tuscaloosa Counties. Their products are divided into two grades, three to four million tons of high Btu, low sulfur steam coal, and five to six million tons of medium to low volatile metallurgical coal. Predominantly, the Blue Creek seam of coal in the Warrior Basin is mined. This coal is known for its high Btu content, low sulfur, and strong coking qualities, coupled with a very high grindability. This last quality of high grindability has been very challenging for their preparation plants. Normally, after some processing degradation,more » their clean coal product will range from 40--50% minus 28 mesh. One can easily see from these numbers that froth flotation is critical to clean coal recovery and mine cost. Flotation, unlike most processing equipment, keeps most of its activity and a lot of its chemistry under a bed of froth in the cells. there are many operating variables that are constantly changing, and Management, no matter how responsive they are, cannot react quickly enough. Therefore, automated flotation appeared to be the natural course of action for a mining company that produces a minimum of 40% of its marketable product from flotation cells. The two companies that were supply their flotation chemicals came forward with proposals to fill their needs. Nalco, who has for some time had their Opticus system being tested and utilized in the industry, and Stockhausen (formerly Betz Chemical Co.). Stockhausen had no system of their own, but acquired a system from Process Technology, Inc. (PTI). JWR assigned a plant to each vendor for installation of their systems. The paper describes both systems and their performance.« less

Use of modflow drain package for simulating inter-basin transfer in abandoned coal mines

USGS Publications Warehouse

Kozar, Mark D.; McCoy, Kurt J.

2017-01-01

Simulation of groundwater flow in abandoned mines is difficult, especially where flux to and from mines is unknown or poorly quantified, and inter-basin transfer of groundwater occurs. A 3-year study was conducted in the Elkhorn area, West Virginia to better understand groundwater-flow processes and inter-basin transfer in above drainage abandoned coal mines. The study area was specifically selected, as all mines are located above the elevation of tributary receiving streams, to allow accurate measurements of discharge from mine portals and tributaries for groundwater model calibration. Abandoned mine workings were simulated in several ways, initially as a layer of high hydraulic conductivity bounded by lower permeability rock in adjacent strata, and secondly as rows of higher hydraulic conductivity embedded within a lower hydraulic conductivity coal aquifer matrix. Regardless of the hydraulic conductivity assigned to mine workings, neither approach to simulate mine workings could accurately reproduce the inter-basin transfer of groundwater from adjacent watersheds. To resolve the problem, a third approach was developed. The MODFLOW DRAIN package was used to simulate seepage into and through mine workings discharging water under unconfined conditions to Elkhorn Creek, North Fork, and tributaries of the Bluestone River. Drain nodes were embedded in a matrix of uniform hydraulic conductivity cells that represented the coal mine aquifer. Drain heads were empirically defined from well observations, and elevations were based on structure contours for the Pocahontas No. 3 mine workings. Use of the DRAIN package to simulate mine workings as an internal boundary condition resolved the inter-basin transfer problem, and effectively simulated a shift from a topographic- dominated to a dip-dominated flow system, by dewatering overlying unmined strata and shifting the groundwater drainage divide up dip within the Pocahontas No. 3 coal seam several kilometers into the adjacent Bluestone River Watershed. Model simulations prior to use of the DRAIN package for simulating mine workings produced estimated flows of 0.32 to 0.34 m3/s in each of the similar sized Elkhorn Creek and North Fork Watersheds, but failed to estimate inter-basin transfer of groundwater from the adjacent Bluestone River Watershed. The simulation of mine entries and discharge using the MODFLOW DRAIN package produced estimated flows of 0.46 and 0.26 m3/s for the Elkhorn Creek and North Fork watersheds respectively, which matched well measured flows for the respective watersheds of 0.47 and 0.26 m3/s.

TECHNIQUES FOR THE FABRICATION OF GEOMEMBRANE FILLED SEAMS

EPA Science Inventory

Geomembranes employed to overlay the excavation for landfills must be seamed together on-site at the landfill. To ensure the integrity of the containment system of the landfill, these sheets or blankets must be carefully seamed. Present methods in common use are: extrusion fil...

Influence of Joint Configuration on the Strength of Laser Welded Presshardened Steel

NASA Astrophysics Data System (ADS)

Kügler, H.; Mittelstädt, C.; Vollertsen, F.

Presshardened steel is used in nowadays automotive production. Due to its high strength, sheet thicknesses can be reduced which results in decreasing weight of car body components. However, because of microstructure softening and coating agglomerations in the seam, welding is still a challenge. In this paper laser beam welding of 22MnB5 with varying energy input per irradiated area is presented. It is found that increasing energy input per seam length reduces tensile strength. Using a small spot size of 200 μm, tensile strength of 1434 N/mm2 can be reached in bead on plate welds. In lap welds tensile strength is limited because of coating particles agglomerating at the melt pool border line. However, the resulting strength is higher when using several small weld seams than using one seam with the same total seam width. With three weld seams, each 0.5mm in width, tensile strength of 911N/mm2 is reached in lap welding.

Improved Seam-Line Searching Algorithm for UAV Image Mosaic with Optical Flow.

PubMed

Zhang, Weilong; Guo, Bingxuan; Li, Ming; Liao, Xuan; Li, Wenzhuo

2018-04-16

Ghosting and seams are two major challenges in creating unmanned aerial vehicle (UAV) image mosaic. In response to these problems, this paper proposes an improved method for UAV image seam-line searching. First, an image matching algorithm is used to extract and match the features of adjacent images, so that they can be transformed into the same coordinate system. Then, the gray scale difference, the gradient minimum, and the optical flow value of pixels in adjacent image overlapped area in a neighborhood are calculated, which can be applied to creating an energy function for seam-line searching. Based on that, an improved dynamic programming algorithm is proposed to search the optimal seam-lines to complete the UAV image mosaic. This algorithm adopts a more adaptive energy aggregation and traversal strategy, which can find a more ideal splicing path for adjacent UAV images and avoid the ground objects better. The experimental results show that the proposed method can effectively solve the problems of ghosting and seams in the panoramic UAV images.

Calculation of dispersion curves and amplitude-depth distributions of Love channel waves in horizontally-layered media. [In seam; various boundary conditions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rader, D.; Dresen, L.; Ruter, H.

We present dispersion curves, and amplitude-depth distributions of the fundamental and first higher mode of Love seam waves for two characteristic seam models. The first model consists of four layers, representing a coal seam underlain by a root clay of variable thickness. The second model consists of five layers, representing coal seams containing a dirt band with variable position and thickness. The simple three-layer model is used for reference. It is shown that at higher frequencies, depending on the thickness of the root clay and the dirt band, the coal layers alone act as a wave guide, whereas at lowmore » frequencies all layers act together as a channel. Depending on the thickness, and position of the dirt band and the root clay, in the dispersion curves of the group velocity, secondary minima grow in addition to the absolute minima. Furthermore, the dispersion curves of the group velocity of the two modes can overlap. In all these cases, wave groups in addition to the Airy phase of the fundamental mode (propagating with minimum group velocity) occur on the seismograms recorded in in-seam seismic surveys, thus impeding their interpretation. Hence, we suggest the estimation of the dispersion characteristics of Love seam waves in coal seams under investigation preceding actual field surveys. All numerical calculations were performed using a fast and stable phase recursion algorithm.« less

INSPECTION TECHNIQUES FOR THE FABRICATION OF GEOMEMBRANE FIELD SEAMS

EPA Science Inventory

Geomembranes employed to overlay the excavation for landfills must be seamed together at the site of the landfill. o ensure the integrity of the containment system of the landfill, these sheets or blankets must be carefully seamed. he methods in present, common use are extrusion ...

The Petrogenesis of the Unit 7/8 and 11/12 Chrome-spinel Seams of the Rum Eastern Layered Intrusion (NW Scotland) Re-evaluated

NASA Astrophysics Data System (ADS)

O'Driscoll, B.; Daly, J. S.; Emeleus, C. H.; Donaldson, C. H.

2007-12-01

Laterally extensive (~2 mm thick) chrome-spinel seams in the Rum Layered Suite, NW Scotland, occur at the junctions of several of the coupled peridotite-troctolite macro-rhythmic units that make up the bulk of the eastern part of the intrusion. A detailed petrographic study of the rocks immediately above and below two of these seams suggests that existing models for seam formation involving early crystallisation and gravitational settling of chrome-spinel crystals from a newly emplaced body of picritic magma may be flawed. Instead, the textural relationships between minerals suggest that olivine crystallisation in the peridotite above each of the seams occurred before that of most of the chrome-spinel. Reaction textures between olivine and chrome-spinel crystals are commonly observed, with plagioclase usually occurring as thin rims between both olivine and chrome-spinel where both are in close proximity. The textural evidence suggests a significant degree of olivine crystal-shape change; it seems that many of the olivine crystals immediately above the main seams may initially have had much more complex (harrisitic) crystal shapes before modification to simpler morphologies in a crystal mush. Plagioclase occurs in the peridotite as large oikocrysts up to several cm in size. Additionally, the chrome-spinel seams occur only in those units that display extensive evidence of syn-magmatic deformation of unconsolidated cumulate in the underlying troctolite, and the seams themselves often exhibit small-scale load structures. A model suggesting in-situ crystallisation of the chrome-spinel seams is proposed, whereby mixing of an evolved interstitial liquid with a primitive picritic melt occurred approximately at the crystal mush-magma interface. The former was released from the unconsolidated troctolite mush as a response to re-mobilization and chaotic slumping, possibly triggered by emplacement of some of the hot picrite into the crystal mush pile. Significant undercooling in the picrite due to emplacement-related cooling had already produced a crystal framework comprising complex skeletal olivine crystal morphologies with very fast growth rates. It is envisaged that the significantly modified olivine textures in the peridotite immediately above both seams can be attributed to upward- moving porosity waves of the same 'mixed' interstitial melt that precipitated the chrome-spinel seams. In addition to formation of the seams at the main unit junctions, 'necklace' or 'chain-like' distributions of chrome-spinel crystals around olivine crystals in the peridotite, as well as the large plagioclase oikocrysts, argue for the presence of a mobile interstitial melt with a protracted cooling history.

43 CFR 3802.4-3 - Multiple-use conflicts.

Code of Federal Regulations, 2011 CFR

2011-10-01

... MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINING CLAIMS UNDER THE GENERAL MINING LAWS Exploration and Mining, Wilderness Review Program § 3802.4-3 Multiple-use conflicts. In the event that uses...

Environmental risks associated with unconventional gas extraction: an Australian perspective

NASA Astrophysics Data System (ADS)

Mallants, Dirk; Bekele, Elise; Schmidt, Wolfgang; Miotlinski, Konrad; Gerke Gerke, Kirill

2015-04-01

Coal seam gas is naturally occurring methane gas (CH4) formed by the degradation of organic material in coal seam layers over geological times, typically over several millions of years. Unlike conventional gas resources, which occur as discrete accumulations in traps formed by folds and other structures in sedimentary layers, coal seam gas is generally trapped in low permeable rock by adsorption of the gas molecules within the rock formation and cannot migrate to a trap and form a conventional gas deposit. Extraction of coal seam gas requires producers to de pressurise the coal measures by abstracting large amounts of groundwater through pumping. For coal measures that have too low permeabilities for gas extraction to be economical, mechanical and chemical techniques are required to increase permeability and thus gas yield. One such technique is hydraulic fracturing (HF). Hydraulic fracturing increases the rate and total amount of gas extracted from coal seam gas reservoirs. The process of hydraulic fracturing involves injecting large volumes of hydraulic fracturing fluids under high pressure into the coal seam layers to open up (i.e. fracture) the gas-containing coal layers, thus facilitating extraction of methane gas through pumping. After a hydraulic fracturing operation has been completed in a coal seam gas well, the fracturing fluid pressure is lowered and a significant proportion of the injected fluid returns to the surface as "flowback" water via coal seam gas wells. Flowback water is fluid that returns to the surface after hydraulic fracturing has occurred but before the well is put into production; whereas produced water is fluid from the coal measure that is pumped to the surface after the well is in production. This paper summarises available literature data from Australian coal seam gas practices on i) spills from hydraulic fracturing-related fluids used during coal seam gas drilling and hydraulic fracturing operations, ii) leaks to soil and shallow groundwater of flowback water and produced water from surface impoundments, iii) risks from well integrity failure, and iv) increased gas in water bores.

Geology of the Shinarump No. 1 uranium mine, Seven Mile Canyon area, Grand County, Utah

USGS Publications Warehouse

Finch, Warren Irvin

1953-01-01

The Shinarump No. 1 uranium mine is located about 12 miles northwest of Moab, Utah, in the Seven Mile Canyon area, Grand County, Utah. A study was made of the geology of the Shinarump No. 1 mine in order to determine the habits, ore controls, and possible origin of the deposit. Rocks of Permain, Triassic, and Jurassic age crop out in the area mapped. Uranium deposits are found in three zones in the lower 25 feet of the Upper Triassic Chinle formation. The Shinarump No. 1 mine, which is in the lowermost zone, is located on the west flank of the Moab anticline near the Moab fault. The Shinarump No. 1 uranium deposit consists of discontinuous lenticular layers of mineralized rock, irregular in outline, that, in general, follow the bedding. Ore minerals, mainly uranite, impregnate the rock. High-grade seams of uranite and chalcocite occur along bedding planes. Formation of unraninite is later than or simultaneous with most sulfides. Chalcocite may be of two ages, with some being later than uraninite. Uraninite and chalcocite are concentrated in the poorer sorted parts of siltstones. Guides to ore in the Seven Mile Canyon area inferred from the study of the Shinarump No. 1 deposit are the presence of bleached siltstone, copper sulfides, and carbonaceous matter. Results of spectrographic analysis indicated that the mineralizing solutions contained important amounts of barium, vanadium, uranium, and copper as well as lesser amounts of strontium, chromium, boron, yttrium, lead, and zinc. The origin of the Shinarump No. 1 deposit is thought to be hydrothermal, dated as later or early.

The possibility of increasing the efficiency of accessible coal deposits by optimizing dimensions of protective pillars or the scope of exploitation

NASA Astrophysics Data System (ADS)

Bańka, Piotr; Badura, Henryk; Wesołowski, Marek

2017-11-01

One of the ways to protect objects exposed to the influences of mining exploitation is establishing protective pillars for them. Properly determined pillar provides effective protection of the object for which it was established. Determining correct dimensions of a pillar requires taking into account contradictory requirements. Protection measures against the excessive influences of mining exploitation require designing the largest possible pillars, whereas economic requirements suggest a maximum reduction of the size of resources left in the pillar. This paper presents algorithms and programs developed for determining optimal dimensions of protective pillars for surface objects and shafts. The issue of designing a protective pillar was treated as a nonlinear programming task. The objective function are the resources left in a pillar while nonlinear limitations are the deformation values evoked by the mining exploitation. Resources in the pillar may be weighted e.g. by calorific value or by the inverse of output costs. The possibility of designing pillars of any polygon shape was taken into account. Because of the applied exploitation technologies the rectangular pillar shape should be considered more advantageous than the oval one, though it does not ensure the minimization of resources left in a pillar. In this article there is also presented a different approach to the design of protective pillars, which instead of fixing the pillar boundaries in subsequent seams, the length of longwall panels of the designed mining exploitation is limited in a way that ensures the effective protection of an object while maximizing the extraction ratio of the deposit.

A techno-economic model for optimum regeneration of surface mined land

NASA Astrophysics Data System (ADS)

Mukhopadhyay, Manas K.; Sinha, Indra N.

2006-07-01

The recent global scenario in the mineral sector may be characterized by rising competitiveness, increasing production costs and a slump in market price. This has pushed the mineral sector in general and that in the developing countries in particular to a situation where the industry has a limited capacity to sustain unproductive costs. This, more often than not, results in a situation where the industry fails to ensure environmental safeguards during and after mineral extraction. The situation is conspicuous in the Indian coal mining industry where more than 73% production comes from surface operations. India has an ambitious power augmentation projection for the coming 10 years. A phenomenal increase in coal production is proposed from the power grade coalfields in India. One of the most likely fall-outs of land degradation due to mining in these areas would be significant reduction of agricultural and other important land-uses. Currently, backfilling costs are perceived as prohibitive and abandonment of land is the easy way out. This study attempts to provide mine planners with a mathematical model that distributes generated overburden at defined disposal options while ensuring maximization of backfilled land area at minimum direct and economic costs. Optimization has been accomplished by linear programming (LP) for optimum distribution of each year’s generated overburden. Previous year’s disposal quantity outputs are processed as one set of the inputs to the LP model for generation of current year’s disposal output. From various geo-mining inputs, site constants of the LP constraints are calculated. Arrived value of economic vectors, which guide the programming statement, decides the optimal overburden distribution in defined options. The case example (with model test run) indicates that overburden distribution is significantly sensitive to coal seam gradient. The model has universal applicability to cyclic system (shovel dumper combination) of opencast mining of stratified deposits.

Paleoslumps in coal-bearing strata of the Breathitt Group (Pennsylvanian), Eastern Kentucky Coal Field, U.S.A

USGS Publications Warehouse

Greb, S.F.; Weisenfluh, G.A.

1996-01-01

The benefits of geologic analysis for roof-control studies and hazard prediction in coal mines are well documented. Numerous case studies have illustrated the importance of recognizing geologic features such as paleochannels, coal riders, and kettlebottoms in mine roofs. Relatively understudied features, in terms of mining, are paleoslumps. Paleoslumps represent ancient movement and rotation of semi-consolidated sediment. Because bedding in paleoslumps is deformed or inclined, these features cause instability in mine roofs, haul roads, surface highwalls, and other excavations. Various types of paleoslumps above coals in the Eastern Kentucky Coal Field were studied in order to aid in their recognition and prediction in mines. The paleoslumps studied all showed characteristic slump-deformation features, although some differences in magnitude of deformation and overall slump size were noted. Coals beneath slumps often exhibited folding, reverse displacements, truncation, clastic dikes, and locally increased thickness. Slumps are inferred to have been triggered by a wide range of mechanisms, such as loading of water-saturated sediment on rigid substrates, synsedimentary faulting, and over-pressurization of channel margin and bar slopes. Analysis of paleoslumps in underground mines, where paleoslumps are viewed from beneath rather than in profile is difficult, since characteristic bed rotation may not be conspicuous. Sudden increases in bed-dip angle inferred from changes in rock type or bedding contacts in the roof; occurrence of bounding, polished rotation surfaces; or roof irregularity and occurrence of loading features may indicate the presence of paleoslumps. Another key to recognition may be the sudden appearance of over-thickened coal, which can occur because of slump-created paleotopography, synsedimentary faults, and slump-generated overthrusting. In addition, steeply inclined, folded, or transported coal marginal to paleoslumps can create apparent increases in coal thickness in cores. Although thick coals are obviously a target of exploration, anomalously thick coals may actually indicate adjacent paleoslumps accompanied by hazardous roof conditions and loss of seam thickness.

Modelling of Longwall Mining-Induced Strata Permeability Change

NASA Astrophysics Data System (ADS)

Adhikary, D. P.; Guo, H.

2015-01-01

The field measurement of permeability within the strata affected by mining is a challenging and expensive task, thus such tests may not be carried out in large numbers to cover all the overburden strata and coal seams being affected by mining. However, numerical modelling in conjunction with a limited number of targeted field measurements can be used efficiently in assessing the impact of mining on a regional scale. This paper presents the results of underground packer testing undertaken at a mine site in New South Wales in Australia and numerical simulations conducted to assess the mining-induced strata permeability change. The underground packer test results indicated that the drivage of main headings (roadways) had induced a significant change in permeability into the solid coal barrier. Permeability increased by more than 50 times at a distance of 11.2-11.5 m from the roadway rib into the solid coal barrier. The tests conducted in the roof strata above the longwall goaf indicated more than 1,000-fold increase in permeability. The measured permeability values varied widely and strangely on a number of occasions; for example the test conducted from the main headings at the 8.2-8.5 m test section in the solid coal barrier showed a decline in permeability value as compared to that at the 11.2-11.5 m section contrary to the expectations. It is envisaged that a number of factors during the tests might have had affected the measured values of permeability: (a) swelling and smearing of the borehole, possibly lowering the permeability values; (b) packer bypass by larger fractures; (c) test section lying in small but intact (without fractures) rock segment, possibly resulting in lower permeability values; and (d) test section lying right at the extensive fractures, possibly measuring higher permeability values. Once the anomalous measurement data were discarded, the numerical model results could be seen to match the remaining field permeability measurement data reasonably well.

Three-dimensional numerical modeling of full-space transient electromagnetic responses of water in goaf

NASA Astrophysics Data System (ADS)

Chang, Jiang-Hao; Yu, Jing-Cun; Liu, Zhi-Xin

2016-09-01

The full-space transient electromagnetic response of water-filled goaves in coal mines were numerically modeled. Traditional numerical modeling methods cannot be used to simulate the underground full-space transient electromagnetic field. We used multiple transmitting loops instead of the traditional single transmitting loop to load the transmitting loop into Cartesian grids. We improved the method for calculating the z-component of the magnetic field based on the characteristics of full space. Then, we established the fullspace 3D geoelectrical model using geological data for coalmines. In addition, the transient electromagnetic responses of water-filled goaves of variable shape at different locations were simulated by using the finite-difference time-domain (FDTD) method. Moreover, we evaluated the apparent resistivity results. The numerical modeling results suggested that the resistivity differences between the coal seam and its roof and floor greatly affect the distribution of apparent resistivity, resulting in nearly circular contours with the roadway head at the center. The actual distribution of apparent resistivity for different geoelectrical models of water in goaves was consistent with the models. However, when the goaf water was located in one side, a false low-resistivity anomaly would appear on the other side owing to the full-space effect but the response was much weaker. Finally, the modeling results were subsequently confirmed by drilling, suggesting that the proposed method was effective.

"Knitting Nannas" and "Frackman": A Gender Analysis of Australian Anti-Coal Seam Gas Documentaries (CSG) and Implications for Environmental Adult Education

ERIC Educational Resources Information Center

Larri, Larraine J.; Newlands, Maxine

2017-01-01

"Frackman" ("FM") and "Knitting Nannas" ("KN") are two documentaries about the anti-coal seam gas movement in Australia. "Frackman" features a former construction worker turned eco-activist, Dayne Pratzky (DP), fighting coal seam gas extraction. "Knitting Nannas" follows a group of women…

30 CFR 75.501 - Permissible electric face equipment; coal seams above water table.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Permissible electric face equipment; coal seams... Equipment-General § 75.501 Permissible electric face equipment; coal seams above water table. [Statutory Provision] On and after March 30, 1974, all electric face equipment, other than equipment referred to in...

Improved Seam-Line Searching Algorithm for UAV Image Mosaic with Optical Flow

PubMed Central

Zhang, Weilong; Guo, Bingxuan; Liao, Xuan; Li, Wenzhuo

2018-01-01

Ghosting and seams are two major challenges in creating unmanned aerial vehicle (UAV) image mosaic. In response to these problems, this paper proposes an improved method for UAV image seam-line searching. First, an image matching algorithm is used to extract and match the features of adjacent images, so that they can be transformed into the same coordinate system. Then, the gray scale difference, the gradient minimum, and the optical flow value of pixels in adjacent image overlapped area in a neighborhood are calculated, which can be applied to creating an energy function for seam-line searching. Based on that, an improved dynamic programming algorithm is proposed to search the optimal seam-lines to complete the UAV image mosaic. This algorithm adopts a more adaptive energy aggregation and traversal strategy, which can find a more ideal splicing path for adjacent UAV images and avoid the ground objects better. The experimental results show that the proposed method can effectively solve the problems of ghosting and seams in the panoramic UAV images. PMID:29659526

Modeling of Three Flat Coal Seams Strata Developing at Open Pit Miming

NASA Astrophysics Data System (ADS)

Gvozdkova, Tatiana; Markov, Sergey; Demirel, Nuray; Anyona, Serony

2017-11-01

The use of low-cost direct dumpling technology, as is well known, has a relatively limited field of application: flat coal seams, and the higher the dip angle of the seam, the more difficult it is to place the necessary volume of overburden rock in the dumping layers. For this, we have to pour four-tier dumps. In this article, four possible options for piling the dump have been studied and prerequisites have been made for further research aimed at improving the efficiency of the use of direct dumpling technology in the development of flat coal seams.

Weld repair method for aluminum lithium seam

NASA Technical Reports Server (NTRS)

McGee, William Floyd (Inventor); Rybicki, Daniel John (Inventor)

1998-01-01

Aluminum-lithium plates are butt-welded by juxtaposing the plates and making a preliminary weld from the rear or root side of the seam. An initial weld is then made from the face side of the seam, which may cause a defect in the root portion. A full-size X-ray is made and overlain over the seam to identify the defects. The defect is removed from the root side, and rewelded. Material is then removed from the face side, and the cavity is rewelded. The procedure repeats, alternating from the root side to the face side, until the weld is sound.

Fermentation Enhancement of Methanogenic Archaea Consortia from an Illinois Basin Coalbed via DOL Emulsion Nutrition

PubMed Central

Xiao, Dong; Peng, Su-Ping; Wang, En-Yuan

2015-01-01

Microbially enhanced coalbed methane technology must be used to increase the methane content in mining and generate secondary biogenic gas. In this technology, the metabolic processes of methanogenic consortia are the basis for the production of biomethane from some of the organic compounds in coal. Thus, culture nutrition plays an important role in remediating the nutritional deficiency of a coal seam. To enhance the methane production rates for microorganism consortia, different types of nutrition solutions were examined in this study. Emulsion nutrition solutions containing a novel nutritional supplement, called dystrophy optional modification latex, increased the methane yield for methanogenic consortia. This new nutritional supplement can help methanogenic consortia form an enhanced anaerobic environment, optimize the microbial balance in the consortia, and improve the methane biosynthesis rate. PMID:25884952

Numerical Modelling by FLAC on Coal Fires in North China

NASA Astrophysics Data System (ADS)

Gusat, D.; Drebenstedt, C.

2009-04-01

Coal fires occur in many countries all over the world (e.g. Australia, China, India, Indonesia, USA and Russia) in underground and on surface. In China the most coal fires occur especially in the North. Economical and environmental damages are the negative effects of the coal fires: coal fires induce open fractures and fissures within the seam and neighbouring rocks. So that these are the predominant pathways for oxygen flow and exhaust gases from a coal fire. All over northern China there are a large number of coal fires, which cause and estimated yearly coal loss of between 100 and 200 million tons ([1], [2], [3]). Spontaneous combustion is a very complicated process and is influenced by number of factors. The process is an exothermic reaction in which the heat generated is dissipated by conduction to the surrounding environment, by radiation, by convection to the ventilation flow, and in some cases by evaporation of moisture from the coal [4]. The coal fires are very serious in China, and the dangerous extent of spontaneous combustion is bad which occupies about 72.9% in mining coal seams. During coal mining in China, the coal fires of spontaneous combustion are quite severity. The dangerous of coal spontaneous combustion has been in 56% of state major coalmines [5]. The 2D and 3D-simulation models describing coal fire damages are strong tools to predict fractures and fissures, to estimate the risk of coal fire propagation into neighbouring seams, to test and evaluate coal fire fighting and prevention methods. The numerical simulations of the rock mechanical model were made with the software for geomechanical and geotechnical calculations, the programs FLAC and FLAC3D [6]. To fight again the coal fires, exist several fire fighting techniques. Water, slurries or liquefied nitrogen can be injected to cool down the coal or cut of air supply with the backfill and thereby extinct the fire. Air supply also can be cut of by covering the coal by soil or sealing of the coal mine with the backfill. A smaller fires can also be handled by taking out burning coal by bulldozing techniques described above are applicable to small fires, but they do not work well in extinction of large coal fires. References [1] http://www.coalfire.caf.dlr.de [2] Schalke, H.J.W.G.; Rosema, A.; Van Genderen, J.L. (1993): Environmental monitoring of coal fires in North China. Project Identification Mission Report. Report Remote Sensing Programme Board, Derft, the Netherlands. [3] Zhang, X.; Kroonenberg, S. B.; De Boer, C. B. (2004): Dating of coal fires in Xinjiang, north-west China. Terra Nova. Band 16, No 2, S. 68-74. DOI: 10.1111/j.1365-3121.2004.00532.x [4] Deng Jun, Hou Shuang, Li Huirong, e.t.c (2006): Oxidation Mechanism at Initial Stage of a Simulated Coal Molecule with -CH2O-[J]. Journal of Changchun University of Science and Technology, 29(2), P. 84-87. [5] Deng, Jun (2008): Presentation. Chinese Researches and Practical Experiences on Controlling Underground Coal Fires. The 2nd Australia-China Symposium on Science, Technology and Education. 15-18 October 2008, Courtyard Marriott, Surfers Paradise Beach, Gold Coast, Queensland, Australia. [6] Itasca (2003): FLAC, Fast Lagrangian Analysis of Continua. Itasca Consultants Group, Inc., Minneapolis.

76 FR 30241 - Pipeline Safety: Notice of Public Meetings on Managing Challenges With Pipeline Seam Welds and...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-05-24

... involving seam weld anomalies and gaps in data and recordkeeping are driving a stronger focus on better... measures. These public meetings are designed to provide an open forum for exchanging information on the... determining the nature and extent of the seam weld issue from industry and government data. 2. Presenting...

Vadose Zone Fate and Transport Simulation of Chemicals Associated with Coal Seam Gas Extraction

NASA Astrophysics Data System (ADS)

Simunek, J.; Mallants, D.; Jacques, D.; Van Genuchten, M.

2017-12-01

The HYDRUS-1D and HYDRUS (2D/3D) computer software packages are widely used finite element models for simulating the one-, and two- or three-dimensional movement of water, heat, and multiple solutes in variably-saturated media, respectively. While the standard HYDRUS models consider only the fate and transport of individual solutes or solutes subject to first-order degradation reactions, several specialized HYDRUS add-on modules can simulate far more complex biogeochemical processes. The objective of this presentation is to provide an overview of the HYDRUS models and their add-on modules, and to demonstrate applications of the software to the subsurface fate and transport of chemicals involved in coal seam gas extraction and water management operations. One application uses the standard HYDRUS model to evaluate the natural soil attenuation potential of hydraulic fracturing chemicals and their transformation products in case of an accidental release. By coupling the processes of retardation, first-order degradation and convective-dispersive transport of the biocide bronopol and its degradation products, we demonstrated how natural attenuation reduces initial concentrations by more than a factor of hundred in the top 5 cm of the vadose zone. A second application uses the UnsatChem module to explore the possible use of coal seam gas produced water for sustainable irrigation. Simulations with different irrigation waters (untreated, amended with surface water, and reverse osmosis treated) provided detailed results regarding chemical indicators of soil and plant health, notably SAR, EC and sodium concentrations. A third application uses the coupled HYDRUS-PHREEQC module to analyze trace metal transport involving cation exchange and surface complexation sorption reactions in the vadose zone leached with coal seam gas produced water following some accidental water release scenario. Results show that the main process responsible for trace metal migration is complexation of naturally present trace metals with inorganic ligands such as (bi)carbonate that enter the soil upon infiltration with alkaline produced water.

Study of in-situ formation of Fe-Mn-Si shape memory alloy welding seam by laser welding with filler powder

NASA Astrophysics Data System (ADS)

Ju, Heng; Lin, Chengxin; Liu, Zhijie; Zhang, Jiaqi

2018-08-01

To reduce the residual stresses and improve the mechanical properties of laser weldments, produced with the restrained mixing uniform design method, a Fe-Mn-Si shape memory alloy (SMA) welding seam was formed inside the 304 stainless steel by laser welding with powder filling. The mass fraction, shape memory effect, and phase composition of the welding seam was measured by SEM-EDS (photometric analyser), bending recovery method, and XRD, respectively. An optical microscope was used to observe the microstructure of the Fe-Mn-Si SMA welding seam by solid solution and pre-deformation treatment. Meanwhile, the mechanical properties (residual stress distribution, tensile strength, microhardness and fatigue strength) of the laser welded specimen with an Fe-Mn-Si SMA welding seam (experimental material) and a 304 stainless steel welding seam (contrast material) were measured by a tensile testing machine hole drilling method and full cycle bending fatigue test. The results show that Fe15Mn5Si12Cr6Ni SMA welding seam was formed in situ with shape memory effect and stress-induced γ → ε martensite phase transformation characteristic. The residual stress of the experimental material is lower than that of the contrast material. The former has larger tensile strength, longer elongation and higher microhardness than the latter has. The experimental material and contrast material possess 249 and 136 bending fatigue cycles at the strain of 6%, respectively. The mechanisms by which mechanical properties of the experimental material are strengthened includes (1) release of the residual stress inside the Fe-Mn-Si SMA welding seam due to the stress-induced γ → ε martensite phase transformation and (2) energy absorption and plastic slip restraint due to the deformations in martensite and reverse phase transformation.

The Method of Validity Evaluation of Hard Coal Excavation in Residual Seam Parts

NASA Astrophysics Data System (ADS)

Wodarski, Krzysztof; Bijańska, Jolanta; Gumiński, Adam

2017-12-01

The excavation of residual seam parts should be justified by positive assessment of the purposefulness, technical feasibility and economic effectiveness. The results of the profitability evaluation are crucial in a decision making process. The excavation of residual seam parts, even if it is possible from a technical point of view, should not be implemented if it is economically inefficient or when accompanied by a very high risk of non-recovery of invested capital resources. The article presents the evaluation method of possibilities of excavating hard coal from residual seam parts, and the example of its use in one of collieries in the Upper Silesian Coal Basin. Working in line with the developed method, allows to indicate the variant of residual seam part exploitation, which is feasible to implement from a technical point of view, and which is characterized by the highest economic effectiveness and lowest risk.

Shielding techniques tackle EMI excesses. V - EMI shielding

NASA Astrophysics Data System (ADS)

Grant, P.

1982-10-01

The utilization of shielding gaskets in EMI design is presented in terms of seam design, gasket design, groove design, and fastener spacing. The main function of seam design is to minimize the coupling efficiency of a seam, and for effective shielding, seam design should include mating surfaces which are as flat as possible, and a flange width at least five times the maximum anticipated separation between mating surfaces. Seam surface contact with a gasket should be firm, continuous, and uniform. Gasket height, closure pressure, and compression set as a function of the applied pressure parameters are determined using compression/deflection curves. Environmental seal requirements are given and the most common materials used are neoprene, silicone, butadiene-acrylonitrile, and natural rubber. Groove design is also discussed, considering gasket heights and cross-sectional areas. Finally, fastener spacing is considered, by examining deflection as a percentage of gasket height.

The Oligocene flora from the Uricani coalfield, Petrosani Basin, Romania

NASA Astrophysics Data System (ADS)

Pirnea, Roxana; Popa, Mihai E.

2017-04-01

The Petrosani Basin is a typical Oligocene - Miocene intramontaneous basin located in the South Carpathians. It has a SW-NE orientation and is 48-km long; its width is varying between 10 and 2 km, and it overlays the Danubian and Getic basements. The Oligocene sequences are filling the basin, with a thickness ranging between 300 and 500 m. They consist of clays, marls, bituminous shales, microconglomerates and limestones, including 22 coal beds. One essential feature of the Petrosani Basin is the occurrence of thick coal seams and the remains of a rich, 28 milion years old ecosystem. The studied material was collected from Uricani coal mine, from the „Lower Productive Horizon", Chattian in age (Upper Oligocene), and from Uricani coal waste dumps. The Lower Productive Horizon, also described as the Dalja-Uricani Formation, includes several coal seams and crops out in several areas (Buia et al., 2014). Collecting fossil plants from underground mining horizons represents a unique method for detailed understanding of coal bearing formations in a three-dimensional approach (Popa, 2011). Although the plant remains are represented by a large number of species, most specimens belong to the Family Lauraceae. The fossil flora is very well preserved, some of the leaves preserving their cuticles. The fossil plants from Uricani coal mine, Petro?ani Basin, are described, illustrated and discussed based on leaf impressions. The associated macroflora of Uricani coal mine comprises various leaf species of Daphnogene, Laurophyllum, Ocotea, Smilax and Alnus. Most of the studied woody plants are mesophytic, like Lauraceae (narrow-leaved Daphnogene, Laurophyllum), but the affinities of the plant remains from Uricani coalfield have not been clarified yet. Nonetheless, the taxonomic composition of the studied flora from Uricani coalfield points to a semi-tropical climate. The overall character of the depositional conditions of Petrosani Basin fit best to a flatland with surrounding uplands, within a typical intramontaneous depression. The fossil flora of the Petrosani Basin was first cited by Stur (1863). Pop (1975) contributed with a study on the geology of the Uricani mining field, with special emphasis on coalbeds. A paleobotanical overview of the plant remains from Petrosani Basin related to coal deposits was also published by Givulescu (1996). This paper refers to the Oligocene fossil flora of Uricani coalfield, as a part of the Petrosani Basin and to the reconstruction of its paleoenvironment. References: Buia, G., et al. (2014). Role of Jiu valley hard coal deposits between eastern and western european energetic constraints. 6th International Multidisciplinary Scientific Symposium „Universitaria Simpro 2014". Petrosani: 22-27. Givulescu, R. (1996). Flora Oligocena Superioara din Bazinul Petrosani (Flora fosila a Bazinului Vaii Jiului). Cluj-Napoca, Casa Cartii de Stiinta. Pop, E. (1975). Studiul geologic al campului minier Uricani cu privire speciala asupra caracteristicilor distinctive ale stratelor de carbuni si asupra tectonicii zacamantului: 206. Popa, M.E., 2011. Field and laboratory techniques in plant compressions: an integrated approach. Acta Palaeontologica Romaniae 7, 279-283. Stur, D. (1863). Bericht über die geoloische Übersichtsaufnahme des südliches Siebenbürgen im Sommer 1860. Jb. k.k. Geol. R.A. 13: 33-120.

The Spectral Element Method for Geophysical Flows

NASA Astrophysics Data System (ADS)

Taylor, Mark

1998-11-01

We will describe SEAM, a Spectral Element Atmospheric Model. SEAM solves the 3D primitive equations used in climate modeling and medium range forecasting. SEAM uses a spectral element discretization for the surface of the globe and finite differences in the vertical direction. The model is spectrally accurate, as demonstrated by a variety of test cases. It is well suited for modern distributed-shared memory computers, sustaining over 24 GFLOPS on a 240 processor HP Exemplar. This performance has allowed us to run several interesting simulations in full spherical geometry at high resolution (over 22 million grid points).

Conical intersection seams in polyenes derived from their chemical composition

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nenov, Artur; Vivie-Riedle, Regina de

2012-08-21

The knowledge of conical intersection seams is important to predict and explain the outcome of ultrafast reactions in photochemistry and photobiology. They define the energetic low-lying reachable regions that allow for the ultrafast non-radiative transitions. In complex molecules it is not straightforward to locate them. We present a systematic approach to predict conical intersection seams in multifunctionalized polyenes and their sensitivity to substituent effects. Included are seams that facilitate the photoreaction of interest as well as seams that open competing loss channels. The method is based on the extended two-electron two-orbital method [A. Nenov and R. de Vivie-Riedle, J. Chem.more » Phys. 135, 034304 (2011)]. It allows to extract the low-lying regions for non-radiative transitions, which are then divided into small linear segments. Rules of thumb are introduced to find the support points for these segments, which are then used in a linear interpolation scheme for a first estimation of the intersection seams. Quantum chemical optimization of the linear interpolated structures yields the final energetic position. We demonstrate our method for the example of the electrocyclic isomerization of trifluoromethyl-pyrrolylfulgide.« less

Characterization of Rare Earth Elements in in Clay Deposits Associated with Central Appalachian Coal Seams

NASA Astrophysics Data System (ADS)

Scott, M.; Verba, C.; Falcon, A.; Poston, J.; McKoy, M.

2017-12-01

Because of their multiple uses in clean energy technologies, rare earth elements (REE) are critical for national economic and energy security. With no current domestic source, supply remains a major concern for domestic security. Underclay - specifically the layer of stratum beneath a coal bed - is a potentially rich source of REE. This study focuses on the characterization and ion exchange recovery of REE from underclay samples from the Lower Freeport, Middle Kittanning, and Pittsburgh coal seams in West Virginia. Multimodal techniques provided quantitative assessments of REE-bearing mineral phases in select underclays and the influence of organic acid rock treatment on the recovery of REE from both exchangeable and crystalline mineral phases present. All samples are from extensively weathered horizons that contain abundant kaolinite and illite. Total REE concentrations range from 250-450 ppm and all samples have a HREE/LEEE ratio >20%. Rare earth element bearing minerals identified in the clay are monazite, xenotime, florencite, and crandallite. Our selective recovery approach is designed to isolate and recover REE through partial dissolution of the clay matrix and ion exchange rather than dissolution/recovery of phosphate or aluminosilicate bound REE. These results provide a better understanding of coal seam underclay, the affinity of REEs for specific ligands and colloids, and how the rock and ligands respond to different chemical treatments. These processes are important to the development and commercialization of efficient and cost effective methods to extract REE from domestic geologic deposits and recover into salable forms.

UNDERGROUNG PLACEMENT OF COAL PROCESSING WASTE AND COAL COMBUSTION BY-PRODUCTS BASED PASTE BACKFILL FOR ENHANCED MINING ECONOMICS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Y.P. Chugh; D. Biswas; D. Deb

2002-06-01

This project has successfully demonstrated that the extraction ratio in a room-and-pillar panel at an Illinois mine can be increased from the current value of approximately 56% to about 64%, with backfilling done from the surface upon completion of all mining activities. This was achieved without significant ground control problems due to the increased extraction ratio. The mined-out areas were backfilled from the surface with gob, coal combustion by-products (CCBs), and fine coal processing waste (FCPW)-based paste backfill containing 65%-70% solids to minimize short-term and long-term surface deformations risk. This concept has the potential to increase mine productivity, reduce miningmore » costs, manage large volumes of CCBs beneficially, and improve the miner's health, safety, and environment. Two injection holes were drilled over the demonstration panel to inject the paste backfill. Backfilling was started on August 11, 1999 through the first borehole. About 9,293 tons of paste backfill were injected through this borehole with a maximum flow distance of 300-ft underground. On September 27, 2000, backfilling operation was resumed through the second borehole with a mixture of F ash and FBC ash. A high-speed auger mixer (new technology) was used to mix solids with water. About 6,000 tons of paste backfill were injected underground through this hole. Underground backfilling using the ''Groutnet'' flow model was simulated. Studies indicate that grout flow over 300-foot distance is possible. Approximately 13,000 tons of grout may be pumped through a single hole. The effect of backfilling on the stability of the mine workings was analyzed using SIUPANEL.3D computer program and further verified using finite element analysis techniques. Stiffness of the backfill mix is most critical for enhancing the stability of mine workings. Mine openings do not have to be completely backfilled to enhance their stability. Backfill height of about 50% of the seam height is adequate to minimize surface deformations. Freeman United Coal Company performed engineering economic evaluation studies for commercialization. They found that the costs for underground management at the Crown III mine would be slightly higher than surface management at this time. The developed technologies have commercial potential but each site must be analyzed on its merit. The Company maintains significant interest in commercializing the technology.« less

Sorption characteristic of coal as regards of gas mixtures emitted in the process of the self-heating of coal

NASA Astrophysics Data System (ADS)

Wojtacha-Rychter, Karolina; Smoliński, Adam

2017-10-01

One of the most challenging tasks in the coal mining sector is the detection of endogenous fire risks. Under field conditions, the distance between the points where samples for the analyses are collected and the actual place where coal self-heating takes place may be quite remote. Coal is a natural sorbent with a diverse character of pore structures which are surrounded by fractures and cleavage planes constituting ideal spaces for the flow and adsorption of gases. The gases (methane, ethane, ethylene, propane, propylene, acetylene, carbon dioxide, carbon monoxide, hydrogen) released from the source of fire migrate through the seam and may be subject to adsorption, or they may cause the desorption of gases accumulated in coal. Therefore, the values of reference sample concentrations may be overstated or understated, respectively. The objective of this experimental study was to investigate the adsorption phenomena accompanying the flow of a multi-component gas mixture through a coal bed which may occur in situ. The research was conducted by means of a method based on a series of calorimetric/chromatographic measurements taken to determine the amount of gases released during coal heating at various temperatures under laboratory conditions. Based on the results obtained in the course of the experiments, it was concluded that the amount of gas adsorbed in the seam depends on the type of coal and the gas. Within the multi-component gas mixture, hydrocarbons demonstrated the largest sorption capacity, especially as concerns propylene.

Solvent Refined Coal (SRC) process. Research and development report No. 53, interim report No. 29, August-November, 1978. Volume VI. Process development unit studies. Part 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1980-01-01

This report presents the results of seven SRC-II runs on Process Development Unit P99 feeding Pittsburgh Seam coal. Four of these runs (Runs 41-44) were made feeding coal from the Robinson Run Mine and three (Runs 45-47) were made feeding a second shipment of coal from the Powhatan No. 5 Mine. This work showed that both these coals are satisfactory feedstocks for the SRC-II process. Increasing dissolver outlet hydrogen partial pressure from approximately 1300 to about 1400 psia did not have a significant effect on yields from Robinson Run coal, but simultaneously increasing coal concentration in the feed slurry frommore » 25 to 30 wt% and decreasing the percent recycle solids from 21% to 17% lowered distillate yields. With the Powhatan coal, a modest increase in the boiling temperature (approximately 35/sup 0/F) at the 10% point) of the process solvent had essentially no effect on product yields, while lowering the average dissolver temperature from 851/sup 0/F to 842/sup 0/F reduced gas yield.« less

Advanced Coal Liquefaction Research and Development Facility, Wilsonville, Alabama. Run 260 with Black Thunder Mine subbituminous coal: Technical progress report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This report presents the results of Run 260 performed at the Advanced Coal Liquefaction R&D Facility in Wilsonville. The run was started on July 17, 1990 and continued until November 14, 1990, operating in the Close-Coupled Integrated Two-Stage Liquefaction mode processing Black Thunder mine subbituminous coal (Wyodak-Anderson seam from Wyoming Powder River Basin). Both thermal/catalytic and catalytic/thermal tests were performed to determine the methods for reducing solids buildup in a subbituminous coal operation, and to improve product yields. A new, smaller interstage separator was tested to reduce solids buildup by increasing the slurry space velocity in the separator. In ordermore » to obtain improved coal and resid conversions (compared to Run 258) full-volume thermal reactor and 3/4-volume catalytic reactor were used. Shell 324 catalyst, 1/16 in. cylindrical extrudate, at a replacement rate of 3 lb/ton of MF coal was used in the catalytic stage. Iron oxide was used as slurry catalyst at a rate of 2 wt % MF coal throughout the run. (TNPS was the sulfiding agent.)« less

Morbidity of British coal miners in 1961-62

PubMed Central

Liddell, F. D. K.

1973-01-01

Liddell, F. D. K. (1973). Brit. J. industr. Med.,30, 1-14. Morbidity of British coal miners in 1961-62. The British coal mining population in 1961 is described, in terms of the 29 084men covered in a 5% sample census, by age, type of employment, coalfield, size of community, degree of mechanization, and other factors. Over a quarter of the men were in jobs not considered specific to coalmining, although nearly half of such men were working underground. The Ministry of Pensions and National Insurance provided records of over 34 000 spells of incapacity due to sickness for these men. Miners were found to suffer much more incapacity for work than men in other employment, even in those non-mining tasks considered to be very arduous. Among miners at the face, elsewhere underground, and on the surface, the lowest paid had the highest rate of incapacity. Incapacity from most causes was also found to vary between coalfields and with size of residential community, and to depend on the men's financial responsibilities, category of pneumoconiosis, and depth of working, but not on the degree of mechanization. A relationship was observed between seam height and the incidence of new spells of beat knee. PMID:4685296

Developing image processing meta-algorithms with data mining of multiple metrics.

PubMed

Leung, Kelvin; Cunha, Alexandre; Toga, A W; Parker, D Stott

2014-01-01

People often use multiple metrics in image processing, but here we take a novel approach of mining the values of batteries of metrics on image processing results. We present a case for extending image processing methods to incorporate automated mining of multiple image metric values. Here by a metric we mean any image similarity or distance measure, and in this paper we consider intensity-based and statistical image measures and focus on registration as an image processing problem. We show how it is possible to develop meta-algorithms that evaluate different image processing results with a number of different metrics and mine the results in an automated fashion so as to select the best results. We show that the mining of multiple metrics offers a variety of potential benefits for many image processing problems, including improved robustness and validation.

40 CFR Table 2 to Subpart Kkkk of... - Emission Limits for Existing Affected Sources

Code of Federal Regulations, 2010 CFR

2010-07-01

... coating a. Two-piece beverage cans—all coatingsb. Two-piece food cans—all coatings c. One-piece aerosol.... Three-piece can assembly a. Inside spray 0.29 (2.43). b. Aseptic side seam stripes on food cans 1.94 (16.16). c. Nonaseptic side seam stripes on food cans 0.79 (6.57). d. Side seam stripes on general line...

40 CFR Table 28 to Subpart G of... - Deck Seam Length Factors a (SD) for Internal Floating Roof Tanks

Code of Federal Regulations, 2011 CFR

2011-07-01

... 40 Protection of Environment 9 2011-07-01 2011-07-01 false Deck Seam Length Factors a (SD) for... (SD) for Internal Floating Roof Tanks Deck construction Typical deck seam length factor Continuous... decks only. Units for SD are feet per square feet. b SD=1/W, where W = sheet width (feet). c If no...

40 CFR Table 28 to Subpart G of... - Deck Seam Length Factors a (SD) for Internal Floating Roof Tanks

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 9 2010-07-01 2010-07-01 false Deck Seam Length Factors a (SD) for... (SD) for Internal Floating Roof Tanks Deck construction Typical deck seam length factor Continuous... decks only. Units for SD are feet per square feet. b SD=1/W, where W = sheet width (feet). c If no...

Resistance of Type 5 chemical protective clothing against nanometric airborne particles: Behavior of seams and zipper.

PubMed

Vinches, Ludwig; Hallé, Stéphane

2017-12-01

In the field of dermal protection, the use of chemical protective clothing (CPC) (including coveralls) are considered as the last barrier against airborne engineered nanomaterials (ENM). In the majority of cases, Type 5 CPC, used against solid particles (ISO 13982-1), perform well against ENM. But in a recent study, a penetration level (PL) of up to 8.5% of polydisperse sodium chloride airborne nanoparticles has been measured. Moreover, in all the previous studies, tests were performed on a sample of protective clothing material without seams or zippers. Thus, the potential for permeation through a zipper or seams has not yet been determined, even though these areas would be privileged entry points for airborne ENM. This work was designed to evaluate the PL of airborne ENM through coveralls and specifically the PL through the seams on different parts of the CPC and the zipper. Eight current models of CPC (Type 5) were selected. The samples were taken from places with and without seams and with a zipper. In some cases, a cover strip can be added to the zipper to enhance its sealing. Polydisperse nanoparticles were generated by nebulization of a sodium chloride solution. A penetration cell was developed to expose the sample to airborne nanometric particles. The NaCl particle concentration in number was measured with an ultrafine particle counter and the PL was defined as the downstream concentration divided by the upstream concentration. The results obtained show that the PL increased significantly in the presence of seams and could reach up to 90% depending on the seam's design. Moreover, this study classifies the different types of seams by their resistance against airborne ENM. As for the penetration of airborne NaCl particles through the zipper, the PL was greatly attenuated by the presence of a cover strip, but only for certain models of coveralls. Finally, the values of the pressure drop were directly linked to the type of seam. All of these conclusions provide recommendations to both manufacturers and users.

3D Discrete element approach to the problem on abutment pressure in a gently dipping coal seam

NASA Astrophysics Data System (ADS)

Klishin, S. V.; Revuzhenko, A. F.

2017-09-01

Using the discrete element method, the authors have carried out 3D implementation of the problem on strength loss in surrounding rock mass in the vicinity of a production heading and on abutment pressure in a gently dripping coal seam. The calculation of forces at the contacts between particles accounts for friction, rolling resistance and viscosity. Between discrete particles modeling coal seam, surrounding rock mass and broken rocks, an elastic connecting element is introduced to allow simulating coherent materials. The paper presents the kinematic patterns of rock mass deformation, stresses in particles and the graph of the abutment pressure behavior in the coal seam.

Replacement of seam welded hot reheat pipe using narrow groove GTA machine welding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Richardson, R.R.; Yanes, J.; Bryant, R.

1995-12-31

Southern California Edison, recognizing a potential safety concern, scrutinized its existing seam welded hot reheat pipe manufactured by the same supplier as that which failed. Alternatives were narrowed to two in dealing with the installed seam welded pipe. The overriding consideration, however, was one of safety. With this in mind, the utility company evaluated replacement of the seam welded hot reheat pipe with seamless pipe or increasing the frequency of its inspection program. Although increased inspection was much costly, pipe replacement was chosen due to potential safety concerns with seam welded pipe even with more frequent inspection. The utility companymore » then proceeded to determine the most effective method to complete this work. Analysis showed machine-made (automatic) gas tungsten arc welds (GTAW) as the method of choice due to cleanliness and superior mechanical properties. In conjunction with this method, the narrow groove (3{degree} bevel) weld joint as opposed to the traditional groove (37 1/2{degree} bevel) was shown to provide significant technical advantages.« less

Interanal seam loss in Asian turtles of the Cuora flavomarginata complex (Testudines, Geoemydidae)

USGS Publications Warehouse

Ernst, Carl H.; Lovich, Jeffrey E.

2015-01-01

The taxonomy of Asian box turtles of the genus Cuora is complicated by the description of numerous valid and invalid taxa over the last several decades. However, some characteristics used to differentiate species are questionable. Members of the C. flavomarginata complex are defined by some, but not all, taxonomists as having reduced interanal seam lengths relative to other species. We examined the ratio of interanal scute seam length divided by midline anal scute length in C. flavomarginata and C. evelynae. Hatchlings show a seam that divides 100% of the anal scute along the midline. As individuals increase in carapace length, there is a tendency for the percentage to decrease, especially in females, although there is considerable overlap. We suggest that the decrease in interanal seam length is due to abrasion of the plastron on the substrate as turtles grow larger and older. Differences in habitat substrates across the range of the species may contribute to the wide variation we observed.

Process modeling and parameter optimization using radial basis function neural network and genetic algorithm for laser welding of dissimilar materials

NASA Astrophysics Data System (ADS)

Ai, Yuewei; Shao, Xinyu; Jiang, Ping; Li, Peigen; Liu, Yang; Yue, Chen

2015-11-01

The welded joints of dissimilar materials have been widely used in automotive, ship and space industries. The joint quality is often evaluated by weld seam geometry, microstructures and mechanical properties. To obtain the desired weld seam geometry and improve the quality of welded joints, this paper proposes a process modeling and parameter optimization method to obtain the weld seam with minimum width and desired depth of penetration for laser butt welding of dissimilar materials. During the process, Taguchi experiments are conducted on the laser welding of the low carbon steel (Q235) and stainless steel (SUS301L-HT). The experimental results are used to develop the radial basis function neural network model, and the process parameters are optimized by genetic algorithm. The proposed method is validated by a confirmation experiment. Simultaneously, the microstructures and mechanical properties of the weld seam generated from optimal process parameters are further studied by optical microscopy and tensile strength test. Compared with the unoptimized weld seam, the welding defects are eliminated in the optimized weld seam and the mechanical properties are improved. The results show that the proposed method is effective and reliable for improving the quality of welded joints in practical production.

Correlation analysis of the variation of weld seam and tensile strength in laser welding of galvanized steel

NASA Astrophysics Data System (ADS)

Sinha, Amit Kumar; Kim, Duck Young; Ceglarek, Darek

2013-10-01

Many advantages of laser welding technology such as high speed and non-contact welding make the use of the technology more attractive in the automotive industry. Many studies have been conducted to search the optimal welding condition experimentally that ensure the joining quality of laser welding that relies both on welding system configuration and welding parameter specification. Both non-destructive and destructive techniques, for example, ultrasonic inspection and tensile test are widely used in practice for estimating the joining quality. Non-destructive techniques are attractive as a rapid quality testing method despite relatively low accuracy. In this paper, we examine the relationship between the variation of weld seam and tensile shear strength in the laser welding of galvanized steel in a lap joint configuration in order to investigate the potential of the variation of weld seam as a joining quality estimator. From the experimental analysis, we identify a trend in between maximum tensile shear strength and the variation of weld seam that clearly supports the fact that laser welded parts having larger variation in the weld seam usually have lower tensile strength. The discovered relationship leads us to conclude that the variation of weld seam can be used as an indirect non-destructive testing method for estimating the tensile strength of the welded parts.

Developing Image Processing Meta-Algorithms with Data Mining of Multiple Metrics

PubMed Central

Cunha, Alexandre; Toga, A. W.; Parker, D. Stott

2014-01-01

People often use multiple metrics in image processing, but here we take a novel approach of mining the values of batteries of metrics on image processing results. We present a case for extending image processing methods to incorporate automated mining of multiple image metric values. Here by a metric we mean any image similarity or distance measure, and in this paper we consider intensity-based and statistical image measures and focus on registration as an image processing problem. We show how it is possible to develop meta-algorithms that evaluate different image processing results with a number of different metrics and mine the results in an automated fashion so as to select the best results. We show that the mining of multiple metrics offers a variety of potential benefits for many image processing problems, including improved robustness and validation. PMID:24653748

Yield grade and carcass weight effects on the cutability of lamb carcasses fabricated into innovative style subprimals.

PubMed

Garrett, R P; Savell, J W; Cross, H R; Johnson, H K

1992-06-01

Lamb carcass (n = 100) were selected from USDA yield grades (YG) 2, 3, and 4 and carcass weight (CW) groups 20.4 to 24.9, 25.0 to 29.5, and 29.6 to 34.0 kg. Lamb carcass were fabricated into semiboneless and boneless subprimals and trimmed to three s.c. fat trim levels: .64, .25, and .00 cm of fat remaining. Innovative subprimals were fabricated and yields were calculated for the subprimals and dissectible components (lean, bone, connective tissue, external fat, and seam fat) from each of the various subprimals. Carcass weight as a main effect in a two-way analysis of variance did not account for a significant amount of the variation in yield among trimmed subprimals or the percentage of the dissectible components, but USDA YG was a significant main effect in determining variation in yield for many of the subprimals or dissectible components. Muscle seaming of shoulders and legs and removal of excessive tails on the loin and rack resulted in a majority of the seam fat being removed from these cuts. Dissection data clearly showed that seam fat is a major component of rack and shoulder cuts and with increasing fatness or higher numerical yield grade there are clearly increased amounts of this depot. Increased trimming of external fat magnifies and draws more attention to the amount of seam fat remaining. Production of heavy, lean lambs would be more useful in an innovative type of program because of the larger-sized muscles. Heavy, fat lambs would not be as useful because of their decreased yields and excess seam fat located in cuts that cannot be muscled-seamed because of the loss of retail cut integrity. Seam fat was highly correlated to percentage of kidney and pelvic fat and to external fat thickness and with USDA yield grade but was not strongly correlated to carcass weight.

Study on robot motion control for intelligent welding processes based on the laser tracking sensor

NASA Astrophysics Data System (ADS)

Zhang, Bin; Wang, Qian; Tang, Chen; Wang, Ju

2017-06-01

A robot motion control method is presented for intelligent welding processes of complex spatial free-form curve seams based on the laser tracking sensor. First, calculate the tip position of the welding torch according to the velocity of the torch and the seam trajectory detected by the sensor. Then, search the optimal pose of the torch under constraints using genetic algorithms. As a result, the intersection point of the weld seam and the laser plane of the sensor is within the detectable range of the sensor. Meanwhile, the angle between the axis of the welding torch and the tangent of the weld seam meets the requirements. The feasibility of the control method is proved by simulation.

A Comparison between Model Base Hardconstrain, Bandlimited, and Sparse-Spike Seismic Inversion: New Insights for CBM Reservoir Modelling on Muara Enim Formation, South Sumatra

NASA Astrophysics Data System (ADS)

Mohamad Noor, Faris; Adipta, Agra

2018-03-01

Coal Bed Methane (CBM) as a newly developed resource in Indonesia is one of the alternatives to relieve Indonesia’s dependencies on conventional energies. Coal resource of Muara Enim Formation is known as one of the prolific reservoirs in South Sumatra Basin. Seismic inversion and well analysis are done to determine the coal seam characteristics of Muara Enim Formation. This research uses three inversion methods, which are: model base hard- constrain, bandlimited, and sparse-spike inversion. Each type of seismic inversion has its own advantages to display the coal seam and its characteristic. Interpretation result from the analysis data shows that the Muara Enim coal seam has 20 (API) gamma ray value, 1 (gr/cc) – 1.4 (gr/cc) from density log, and low AI cutoff value range between 5000-6400 (m/s)*(g/cc). The distribution of coal seam is laterally thinning northwest to southeast. Coal seam is seen biasedly on model base hard constraint inversion and discontinued on band-limited inversion which isn’t similar to the geological model. The appropriate AI inversion is sparse spike inversion which has 0.884757 value from cross plot inversion as the best correlation value among the chosen inversion methods. Sparse Spike inversion its self-has high amplitude as a proper tool to identify coal seam continuity which commonly appears as a thin layer. Cross-sectional sparse spike inversion shows that there are possible new boreholes in CDP 3662-3722, CDP 3586-3622, and CDP 4004-4148 which is seen in seismic data as a thick coal seam.

Dynamic mapping of conical intersection seams: A general method for incorporating the geometric phase in adiabatic dynamics in polyatomic systems

NASA Astrophysics Data System (ADS)

Xie, Changjian; Malbon, Christopher L.; Yarkony, David R.; Guo, Hua

2017-07-01

The incorporation of the geometric phase in single-state adiabatic dynamics near a conical intersection (CI) seam has so far been restricted to molecular systems with high symmetry or simple model Hamiltonians. This is due to the fact that the ab initio determined derivative coupling (DC) in a multi-dimensional space is not curl-free, thus making its line integral path dependent. In a recent work [C. L. Malbon et al., J. Chem. Phys. 145, 234111 (2016)], we proposed a new and general approach based on an ab initio determined diabatic representation consisting of only two electronic states, in which the DC is completely removable, so that its line integral is path independent in the simply connected domains that exclude the CI seam. Then with the CIs included, the line integral of the single-valued DC can be used to construct the complex geometry-dependent phase needed to exactly eliminate the double-valued character of the real-valued adiabatic electronic wavefunction. This geometry-dependent phase gives rise to a vector potential which, when included in the adiabatic representation, rigorously accounts for the geometric phase in a system with an arbitrary locus of the CI seam and an arbitrary number of internal coordinates. In this work, we demonstrate this approach in a three-dimensional treatment of the tunneling facilitated dissociation of the S1 state of phenol, which is affected by a Cs symmetry allowed but otherwise accidental seam of CI. Here, since the space is three-dimensional rather than two-dimensional, the seam is a curve rather than a point. The nodal structure of the ground state vibronic wavefunction is shown to map out the seam of CI.

Airborne nanoparticle concentrations in the manufacturing of polytetrafluoroethylene (PTFE) apparel.

PubMed

Vosburgh, Donna J H; Boysen, Dane A; Oleson, Jacob J; Peters, Thomas M

2011-03-01

One form of waterproof, breathable apparel is manufactured from polytetrafluoroethylene (PTFE) membrane laminated fabric using a specific process to seal seams that have been sewn with traditional techniques. The sealing process involves applying waterproof tape to the seam by feeding the seam through two rollers while applying hot air (600 °C). This study addressed the potential for exposure to particulate matter from this sealing process by characterizing airborne particles in a facility that produces more than 1000 lightweight PTFE rain jackets per day. Aerosol concentrations throughout the facility were mapped, breathing zone concentrations were measured, and hoods used to ventilate the seam sealing operation were evaluated. The geometric mean (GM) particle number concentrations were substantially greater in the sewing and sealing areas (67,000 and 188,000 particles cm⁻³)) compared with that measured in the office area (12,100 particles cm⁻³). Respirable mass concentrations were negligible throughout the facility (GM = 0.002 mg m⁻³) in the sewing and sealing areas). The particles exiting the final discharge of the facility's ventilation system were dominated by nanoparticles (number median diameter = 25 nm; geometric standard deviation of 1.39). The breathing zone particle number concentrations of the workers who sealed the sewn seams were highly variable and significantly greater when sealing seams than when conducting other tasks (p < 0.0001). The sealing workers' breathing zone concentrations ranged from 147,000 particles cm⁻³ to 798,000 particles cm⁻³, and their seam responsibility significantly influenced their breathing zone concentrations (p = 0.03). The finding that particle number concentrations were approximately equal outside the hood and inside the local exhaust duct indicated poor effectiveness of the canopy hoods used to ventilate sealing operations.

Airborne Nanoparticle Concentrations in the Manufacturing of Polytetrafluoroethylene (PTFE) Apparel

PubMed Central

Vosburgh, Donna J.H.; Boysen, Dane A.; Oleson, Jacob J.; Peters, Thomas M.

2016-01-01

One form of waterproof, breathable apparel is manufactured from polytetrafluoroethylene (PTFE) membrane laminated fabric, using a specific process to seal seams that have been sewn with traditional techniques. The sealing process involves applying waterproof tape to the seam by feeding the seam through two rollers while applying hot air (600°C). This study addressed the potential for exposure to particulate matter from this sealing process, by characterizing airborne particles in a facility that produces over 1,000 lightweight PTFE rain jackets per day. Aerosol concentrations throughout the facility were mapped, breathing zone concentrations were measured, and hoods used to ventilate the seam sealing operation were evaluated. The geometric mean (GM) particle number concentrations were substantially greater in the sewing and sealing areas (67,000 and 188,000 particles cm−3) compared to that measured in the office area (12,100 particles cm−3). Respirable mass concentrations were negligible throughout the facility (GM=0.002 mg m−3 in the sewing and sealing areas). The particles exiting the final discharge of the facility's ventilation system were dominated by nanoparticles (number median diameter = 25 nm; geometric standard deviation of 1.39). The breathing zone particle number concentrations of the workers who sealed the sewn seams were highly variable and significantly greater when sealing seams than when conducting other tasks (p<0.0001). The sealing workers’ breathing zone concentrations ranged from 147,000 particles cm−3 to 798,000 particles cm−3, and their seam responsibility significantly influenced their breathing zone concentrations (p=0.03). The finding that particle number concentrations were approximately equal outside the hood and inside the local exhaust duct indicated poor effectiveness of the canopy hoods used to ventilate sealing operations. PMID:21347955

Compositional mining of multiple object API protocols through state abstraction.

PubMed

Dai, Ziying; Mao, Xiaoguang; Lei, Yan; Qi, Yuhua; Wang, Rui; Gu, Bin

2013-01-01

API protocols specify correct sequences of method invocations. Despite their usefulness, API protocols are often unavailable in practice because writing them is cumbersome and error prone. Multiple object API protocols are more expressive than single object API protocols. However, the huge number of objects of typical object-oriented programs poses a major challenge to the automatic mining of multiple object API protocols: besides maintaining scalability, it is important to capture various object interactions. Current approaches utilize various heuristics to focus on small sets of methods. In this paper, we present a general, scalable, multiple object API protocols mining approach that can capture all object interactions. Our approach uses abstract field values to label object states during the mining process. We first mine single object typestates as finite state automata whose transitions are annotated with states of interacting objects before and after the execution of the corresponding method and then construct multiple object API protocols by composing these annotated single object typestates. We implement our approach for Java and evaluate it through a series of experiments.

Compositional Mining of Multiple Object API Protocols through State Abstraction

PubMed Central

Mao, Xiaoguang; Qi, Yuhua; Wang, Rui; Gu, Bin

2013-01-01

API protocols specify correct sequences of method invocations. Despite their usefulness, API protocols are often unavailable in practice because writing them is cumbersome and error prone. Multiple object API protocols are more expressive than single object API protocols. However, the huge number of objects of typical object-oriented programs poses a major challenge to the automatic mining of multiple object API protocols: besides maintaining scalability, it is important to capture various object interactions. Current approaches utilize various heuristics to focus on small sets of methods. In this paper, we present a general, scalable, multiple object API protocols mining approach that can capture all object interactions. Our approach uses abstract field values to label object states during the mining process. We first mine single object typestates as finite state automata whose transitions are annotated with states of interacting objects before and after the execution of the corresponding method and then construct multiple object API protocols by composing these annotated single object typestates. We implement our approach for Java and evaluate it through a series of experiments. PMID:23844378

Mercury emission from coal seam fire at Wuda, Inner Mongolia, China

NASA Astrophysics Data System (ADS)

Liang, Yanci; Liang, Handong; Zhu, Shuquan

2014-02-01

The underground coal seam fire in the Wuda, Inner Mongolia of china is one of the most serious coal fires in the world with a history over 50 years and endangers the neighboring downwind urban area. To investigate the potential mercury emission and migration from the coal seam fire, in situ real-time measurement of total gaseous mercury (TGM) concentration using Lumex RA-915 + mercury analyzer were implemented on the fire zone and the urban area. The results show an average TGM concentration of 464 ng m-3 in the fumes released from surface vents and cracks on the fire zone, which leads to an elevated TGM concentration of 257 ng m-3 (211-375 ng m-3) in the near-surface air at the fire zone and 89 ng m-3 (23-211 ng m-3) at the peripheral area. The average TGM concentration in the adjoining downwind urban area of Wuda is 33 ng m-3. This result suggests that the coal seam fire may not only contribute to the global mercury inventory but also be a novel source for mercury pollution in the urban areas. The scenario of urban areas being adjacent to coal seam fires is not limited to Wuda but relatively common in northern China and elsewhere. Whether there are other cities under influence of coal seam fires merits further investigation.

Palatal Seam Disintegration: To Die or Not to Die? That Is No Longer the Question

PubMed Central

Nawshad, Ali

2008-01-01

Formation of the medial epithelial seam (MES) by palatal shelf fusion is a crucial step of palate development. Complete disintegration of the MES is the final essential phase of palatal confluency with surrounding mesenchymal cells. In general, the mechanisms of palatal seam disintegration are not overwhelmingly complex, but given the large number of interacting constituents; their complicated circuitry involving feedforward, feedback, and crosstalk; and the fact that the kinetics of interaction matter, this otherwise simple mechanism can be quite difficult to interpret. As a result of this complexity, apparently simple but highly important questions remain unanswered. One such question pertains to the fate of the palatal seam. Such questions may be answered by detailed and extensive quantitative experimentation of basic biological studies (cellular, structural) and the newest molecular biological determinants (genetic/dye cell lineage, gene activity, kinase/enzyme activity), as well as animal model (knockouts, transgenic) approaches. System biology and cellular kinetics play a crucial role in cellular MES function; omissions of such critical contributors may lead to inaccurate understanding of the fate of MES. Excellent progress has been made relevant to elucidation of the mechanism(s) of palatal seam disintegration. Current understanding of palatal seam disintegration suggests epithelial–mesenchymal transition and/or programmed cell death as two most common mechanisms of MES disintegration. In this review, I discuss those two mechanisms and the differences between them. PMID:18629865

Lining seam elimination algorithm and surface crack detection in concrete tunnel lining

NASA Astrophysics Data System (ADS)

Qu, Zhong; Bai, Ling; An, Shi-Quan; Ju, Fang-Rong; Liu, Ling

2016-11-01

Due to the particularity of the surface of concrete tunnel lining and the diversity of detection environments such as uneven illumination, smudges, localized rock falls, water leakage, and the inherent seams of the lining structure, existing crack detection algorithms cannot detect real cracks accurately. This paper proposed an algorithm that combines lining seam elimination with the improved percolation detection algorithm based on grid cell analysis for surface crack detection in concrete tunnel lining. First, check the characteristics of pixels within the overlapping grid to remove the background noise and generate the percolation seed map (PSM). Second, cracks are detected based on the PSM by the accelerated percolation algorithm so that the fracture unit areas can be scanned and connected. Finally, the real surface cracks in concrete tunnel lining can be obtained by removing the lining seam and performing percolation denoising. Experimental results show that the proposed algorithm can accurately, quickly, and effectively detect the real surface cracks. Furthermore, it can fill the gap in the existing concrete tunnel lining surface crack detection by removing the lining seam.

A new protocol to accurately determine microtubule lattice seam location

DOE PAGES

Zhang, Rui; Nogales, Eva

2015-09-28

Microtubules (MTs) are cylindrical polymers of αβ-tubulin that display pseudo-helical symmetry due to the presence of a lattice seam of heterologous lateral contacts. The structural similarity between α- and β-tubulin makes it difficult to computationally distinguish them in the noisy cryo-EM images, unless a marker protein for the tubulin dimer, such as kinesin motor domain, is present. We have developed a new data processing protocol that can accurately determine αβ-tubulin register and seam location for MT segments. Our strategy can handle difficult situations, where the marker protein is relatively small or the decoration of marker protein is sparse. Using thismore » new seam-search protocol, combined with movie processing for data from a direct electron detection camera, we were able to determine the cryo-EM structures of MT at 3.5. Å resolution in different functional states. The successful distinction of α- and β-tubulin allowed us to visualize the nucleotide state at the E-site and the configuration of lateral contacts at the seam.« less

Chamber free fusion welding root side purging method and apparatus

NASA Technical Reports Server (NTRS)

Mcgee, William F. (Inventor); Rybicki, Daniel J. (Inventor)

1993-01-01

A method and apparati are presented for non-chamber root side purging in fusion welding of oxygen reactive metals which require that the molten weld zone and local solid areas of the weld seam remaining at high temperatures be shielded from normal atmosphere to prevent degradation of the welded area. The apparati provide an inert atmosphere to the root side of a weld joint through a porous medium whereby the jet-like thrust of the plasma arc actually draws the continuously supplied inert atmosphere into the path of the molten or high temperature solid weld zone. The porous medium is configured so it can be placed at the borders of the weld seam and substantially parallel to the seam without restricting the view of the root side of the seam. The inert gas is dispersed evenly through the porous media and across the weld seam, at the point of arc penetration and in front of and behind the arc. The apparati can be constructed so as to limit the amount of inert gas flow and can be mobile and travel synchronously with the welding arc.

Leak test fixture and method for using same

DOEpatents

Hawk, Lawrence S.

1976-01-01

A method and apparatus are provided which are especially useful for leak testing seams such as an end closure or joint in an article. The test does not require an enclosed pressurized volume within the article or joint section to be leak checked. A flexible impervious membrane is disposed over an area of the seamed surfaces to be leak checked and sealed around the outer edges. A preselected vacuum is applied through an opening in the membrane to evacuate the area between the membrane and the surface being leak checked to essentially collapse the membrane to conform to the article surface or joined adjacent surfaces. A pressure differential is concentrated at the seam bounded by the membrane and only the seam experiences a pressure differential as air or helium molecules are drawn into the vacuum system through a leak in the seam. A helium detector may be placed in a vacuum exhaust line from the membrane to detect the helium. Alternatively, the vacuum system may be isolated at a preselected pressure and leaks may be detected by a subsequent pressure increase in the vacuum system.

Chamber free fusion welding root side purging method and apparatus

NASA Technical Reports Server (NTRS)

Dailey, J. R. (Inventor); Mcgee, William F. (Inventor); Rybicki, Daniel J. (Inventor)

1995-01-01

A method and apparati are presented for non-chamber root side purging in fusion welding of oxygen reactive metals which require that the molten weld zone and local solid areas of the weld seam remaining at high temperatures be shielded from normal atmosphere to prevent degradation of the welded area. The apparati provide an inert atmosphere to the root side of a weld joint through a porous medium whereby the jet-like thrust of the plasma arc actually draws the continuously supplied inert atmosphere into the path of the molten or high temperature solid weld zone. The porous medium is configured so it can be placed at the borders of the weld seam and substantially parallel to the seam without restricting the view of the root side of the seam. The inert gas is dispersed evenly through the porous media and across the weld seam, at the point of arc penetration and in front of and behind the arc. The apparati can be constructed so as to limit the amount of inert gas flow and can be mobile and travel synchronously with the welding arc.

Pressurized grout remote backfilling at AML sites near Beulah and Zap, North Dakota

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weiner, E.J.; Dodd, W.E.

1999-07-01

The Abandoned Mine Lands (AML) Division of the North Dakota Public Service Commission (PSC) is charged with the reclamation of hazardous abandoned mine sites in North Dakota. Several underground lignite coalmines were operated near the cities of Beulah and Zap, North Dakota, from the early 1900's until about 1955. Coal seams in this area were relatively thick and the overburden generally shallow. As these mines have deteriorated with time, deep collapse features, or sinkholes, have surfaced in many areas. These features are very dangerous, especially when they occur at or near residential and commercial areas and public roads. In themore » past five years, sinkholes have surfaced beneath a commercial building (boat dealership, lounge, and gas station) and beneath a nearby occupied mobile home north of Beulah. sinkholes have also surfaced near KHOL Radio Station in Beulah and in the right of way of a public road south of Zap. The AML Division has conducted several emergency sinkhole-filling projects in these areas. In 1995--97, the AML Division conducted exploratory drilling which confirmed the presence of collapsing underground mines at these sites. The remediation of these sites around Beulah/Zap will take place over several years and involve three or more separate contracts due to budget considerations. In 1997, the AML Division began reclamation at these sties utilizing pressurized grout remote backfilling. In this technique, a cementitious grout is pumped through cased drill holes directly into the mine cavities to fill them and thereby stabilize the surface from collapse. The successful contractor for Phase One of the project was The Concrete Doctor, Inc. (TCDI). This paper will concentrate on Phase One of this work performed from June through September 1997. This project is especially interesting because grout was pumped through holes drilled inside the occupied commercial building. Grout was also pumped through angled holes that intercepted mined workings directly beneath the structure. Several specialized monitoring techniques were used to alert contractor if any movement in the structures occurred during grouting activities. Informational meetings were conducted by TCDI and PDC held with landowners, business owners, residents and road authorities before, during and after the project.« less

Sequential simulation approach to modeling of multi-seam coal deposits with an application to the assessment of a Louisiana lignite

USGS Publications Warehouse

Olea, Ricardo A.; Luppens, James A.

2012-01-01

There are multiple ways to characterize uncertainty in the assessment of coal resources, but not all of them are equally satisfactory. Increasingly, the tendency is toward borrowing from the statistical tools developed in the last 50 years for the quantitative assessment of other mineral commodities. Here, we briefly review the most recent of such methods and formulate a procedure for the systematic assessment of multi-seam coal deposits taking into account several geological factors, such as fluctuations in thickness, erosion, oxidation, and bed boundaries. A lignite deposit explored in three stages is used for validating models based on comparing a first set of drill holes against data from infill and development drilling. Results were fully consistent with reality, providing a variety of maps, histograms, and scatterplots characterizing the deposit and associated uncertainty in the assessments. The geostatistical approach was particularly informative in providing a probability distribution modeling deposit wide uncertainty about total resources and a cumulative distribution of coal tonnage as a function of local uncertainty.

A new seismic probe for coal seam hazard detection

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peters, W.R.; Owen, T.E.; Thill, R.E.

1985-01-01

An experimental hole-to-hole seismic probe system has been developed for use in coal measure geology as a means of determining the structural conditions of coal seams. The source probe produces a 500-joule electric arc discharge whose seismic wavelet has a spectrum in the 200 to 2,000 Hz frequency range. Low compliance hydrophones contained in the source probe as well as in a separate seismic detector probe are matched to the frequency range of the source. Both probes are constructed with 5.72 cm diameter housings. The transducers in the probes are equipped with fluid-inflatable boots to permit operation in either wetmore » or dry boreholes. Preliminary tests in vertical boreholes drilled 213 m apart in sedimentary rock formations show reliable operation and useful seismic propagation measurements along horizontal and oblique paths up to 232 m in length. Because the seismic wavelet has an accurately repeatable waveshape, multiple shots and signal averaging techniques can be used to enhance the signal-to-noise ratio and extend the transmission distances.« less

Oxidation and carbonisation of coals: a case study of coal fire affected coals from the Wuda coalfield, Inner Mongolia, China

NASA Astrophysics Data System (ADS)

Kus, Jolanta; Meyer, Uwe; Ma, Jianwei; Chen-Brauchler, Dai

2010-05-01

At the coalfield of Wuda (Inner Mongolia, PR China) extensive underground coal fires cause widespread thermal and oxidative effects in coal seams. Within phase B of the Coal Fire Research Project of the Sino-German Initiative, methods for innovative fire-extinguishing technologies were investigated in multifaceted research approaches. Extensive investigations of oxidative and thermally affected coal seams in coal fire zone 18 were conducted in 2008 prior to application of new fire-extinguishing methods. We present results from the outcrop of coal seam No. 4 in the fire zone 18. The coal of seam No. 4 is of Early Permian age and belongs stratigraphically to the Shanxi Formation. The unaffected coal displays a high volatile bituminous A rank with a background value of random vitrinite reflectance ranging from 0.90 to 0.96 % Rr. Coal channel samples were coallected at actively extracted coal faces along multiple profiles with surface temperatures ranging from about 50° to 600°C. Microscopic examinations revealed a variety of products of coal exposure to the fire. Within coal samples, a marked rise in vitrinite reflectance from background values to 5.55% Rr (6.00 % Rmax) is encountered. In addition, a number of coal samples showed suppressed vitrinite reflectances ranging between 0.82 to 0.88% Rr. Further, seemingly heat unaffected coal samples display intensive development of oxidations rims at coal grain edges and cracks as well as shrinkage cracks and formation of iron oxides/hydroxides. Instead, thermally affected coal samples with higher coalification grade are further characterised by development of macropores (devolatilisation pores) in vitrinitic streaks, transformation of liptinite to meta-liptinite and micrinite as well as by natural coke particles of mostly porous nature and fine to coarse grained anisotropic mosaic. Coal petrographic investigations confirmed a hypothesis that both, oxidations as well as low temperature carbonisation govern the thermal regime in the coal fire zone 18. The occurrence of various thermal alteration products indicates temperatures in the range of 500-700°C.

Heatshield for Extreme Entry Environment Technology: Results from Acreage and Integrated Seams Arcjet Testing

NASA Technical Reports Server (NTRS)

Venkatapathy, Ethiraj

2016-01-01

This invited talk will give a brief overview of the integrated heat-shield system design that requires seams and the extreme environment conditions that HEEET should be demonstrated to be capable of thermal performance without fail. We have tested HEEET across many different facilities and at conditions that are extreme. The presentation will highlight the performance of both the acreage as well as integrated seam at these conditions. The Invite talks are 10 min and hence this presentation will be short.

Examining microbial community response to a strong chemical gradient: the effects of surface coal mining on stream bacteria

NASA Astrophysics Data System (ADS)

Bier, R.; Lindberg, T. T.; Wang, S.; Ellis, J. C.; Di Giulio, R. T.; Bernhardt, E. S.

2012-12-01

Surface coal mining is the dominant form of land cover change in northern and central Appalachia. In this process, shallow coal seams are exposed by removing overlying rock with explosives. The resulting fragmented carbonate rock and coal residues are disposed of in stream valleys. These valley fills generate alkaline mine drainage (AlkMD), dramatically increasing alkalinity, ionic strength, substrate supply (esp. SO42-), and trace element (Mn, Li, Se, U) concentrations in downstream rivers as well as significant losses of sensitive fish and macroinvertebrate species. In prior work within the Mud River, which drains the largest surface mine complex in Appalachia, we found that concentrations of AlkMD increase proportionally with the extent of upstream mining. Here we ask "How do stream microbial communities change along this strong chemical gradient?" We collected surface water and benthic biofilms from 25 stream reaches throughout the Mud River spanning the full range of surface mining impacts, with 0-96% of the contributing watershed area converted to surface coal mines. Microbial communities were collected from biofilms grown on a common substrate (red maple veneers) that were incubated in each stream reach for four months prior to collection in April, 2011. 16S rRNA genes from microbial communities at each study site were examined using 454 sequencing and compared with a generalized UniFrac distance matrix (674 sequence eveness) that was used in statistical analyses. Water chemistry at the sites was sampled monthly from July 2010 to December 2010 and again in April 2011. In April, surface water concentrations of SO42-, Ca2+, Mg2+, and Se2- increased linearly with the extent of upstream mining (all regressions R2 >0.43; p<0.004), with the resulting gradient in ionic strength extending from low conductivity (average 83 μS cm-1 S.E. 27.4) in unmined streams (n=6) to as high as 899 μS cm-1 in the mainstem and 1889 μS cm-1 immediately below the Connelly Branch valley fill. Across this gradient, we found that microbial community composition varied significantly between sites receiving mine drainage and those that were unexposed (NMDS ordination R2 =0.86; PERMANOVA; p=0.029). Bacterial diversity (OTU richness defined at 3% sequence difference) peaked at intermediate conductivities (600 μS cm-1). Environmental data that correlated significantly with the ordination axes were a variety of surface water ions characteristic of AlkMD (SO42-, Mg2+, Sr2+, Se2-, and U) as well as stream DOC concentrations (p < 0.001).

Physical and hydrologic environments of the Mulberry coal reserves in eastern Kansas

USGS Publications Warehouse

Kenny, J.F.; Bevans, H.E.; Diaz, A.M.

1982-01-01

Strippable reserves of Mulberry coal underlie an area of approximately 300 square miles of Miami, Linn, and Bourbon Counties of eastern Kansas. Although subject to State reclamation law, current and projected strip mining of this relatively thin coal seam could alter and hydrologic environment of the study area. Drained by the Marais des Cygnes and Little Osage Rivers and their tributaries, this area is characterized by low relief and moderately impermeable soils. Streamflows are poorly sustained by ground-water discharge and fluctuate widely due to climatic extremes and usage of surface-water supplies. Because ground-water supplies are generally unreliable in quantity and quality, surface water is used to meet most water requirements in the study area. Primary used of surface waters are for domestic supplies, maintenance of wildlife and recreational areas, and cooling needs at LaCygne Power Plant. The prevailing chemical type of the natural streamflow is calcium bicarbonate, with concentrations of dissolved solids generally less than 500 milligrams per liter and pH near neutral. Additional streamflow and water-quality data are needed to evaluate the premining characteristics of and the anticipated changes in the hydrologic environment as strip mining proceeds within the study area. A network of data-collection stations and a sampling scheme have been established to acquire this additional information. (USGS)

Underground Coal Gasification Research Program near Hanna, Carbon County, Wyoming: Environmental impact assessment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

In the fall of 1972, the Laramie Energy Research Center initiated an in situ coal gasification experiment in Hanna, Wyoming. The objective was to test the feasibility of underground gasification in a deep, thick seam of western subbituminous coal and, if feasible, to maximize gas heating value while sustaining stable gas production rates and achieving a high coal utilization efficiency. The coal seam was ignited on March 28, 1973, in a 30-foot seam 400 feet deep. The ''burn'' was maintained for a year, until March 22, 1974, when air injection was stopped. The combustion zone was extinguished by the naturalmore » influx of seam water in approximately three months. This report discusses the environmental inpacts of this program on the area and provides details of the program. 13 refs., 7 figs., 11 tabs.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, B.E.; Krajewski, S.A.; Ahner, P.F.

The site qualification program for the North Knobs UCG site near Rawlins, Wyoming has been completed. This site will be the location for the field tests of Underground Coal Gasification of Steeply Dipping Beds undertaken by Gulf Research and Development Company for DOE in a cost shared contract. Site characterization included a comprehensive geotechnical analysis along with vegetation, historical, and archeological studies. The G coal seam chosen for these tests is a subbituminous B coal with a true seam thickness of 22 feet and has thin coal benches above and below the main seam. The water table is at 90more » feet below the surface. Hydrologic studies have defined the seam as an aquiclude (non-aquifer). The site is deemed restorable to regulatory requirements. Evaluation of this site indicates total acceptability for the three-test program planned by GR and DC.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, B.E.; Krajewski, S.A.; Ahner, P.F.

The site qualification program for the North Knobs UCG site near Rawlins, Wyoming has been completed. This site will be the location for the field tests of Underground Coal Gasification of Steeply Dipping Beds undertaken by Gulf Research and Development Company for DOE in a cost shared contract. Site characterization included a comprehensive geotechnical analysis along with vegetation, historical, and archeological studies. The G coal seam chosen for these tests is a subbituminous B coal with a true seam thickness of 22 feet and has thin coal benches above and below the main seam. The water table is at 90more » feet below the surface. Hydrologic studies have defined the seam as an aquiclude (nonaquifer). The site is deemed restorable to regulatory requirements. Evaluation of this site indicates total acceptability for the three-test program planned by GR and DC.« less

Prediction of coal grindability from exploration data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gomez, M.; Hazen, K.

1970-08-01

A general prediction model for the Hardgrove grindability index was constructed from 735 coal samples using the proximate analysis, heating value, and sulfur content. The coals used to develop the general model ranged in volatile matter from 12.8 to 49.2 percent, dry basis, and had grindability indexes ranging from 35 to 121. A restricted model applicable to bituminous coals having grindabilities in the 40 to 110 range was developed from the proximate analysis and the petrographic composition of the coal. The prediction of coal grindability within a single seam was also investigated. The results reported support the belief that mechanicalmore » properties of the coal are related to both chemical and petrographic factors of the coal. The mechanical properties coal may be forecast in advance of mining, because the variables used as input to the prediction models can be measured from drill core samples collected during exploration.« less

Respiratory health status of gilsonite workers.

PubMed

Keimig, D G; Castellan, R M; Kullman, G J; Kinsley, K B

1987-01-01

Gilsonite, a solidified hydrocarbon used in the manufacture of automotive body seam sealers, is mined only in the Uinta Basin of Eastern Utah and Western Colorado. Health effects of gilsonite dust exposure have not previously been published and exposure to gilsonite dust is not regulated. To examine potential respiratory health effects associated with gilsonite dust exposures, this cross-sectional study surveyed the 100 current male employees who had been exposed to gilsonite dust at 3 existing gilsonite companies. Total dust exposures up to 28 times the nuisance dust standard were found, and 5 of 99 (5%) workers had chest radiographs consistent with pneumoconiosis of low profusion. Increased prevalences of cough and phlegm were found in workers with high-exposure jobs, but no evidence for dust-related pulmonary function impairment was noted. To prevent pulmonary health effects, we recommend reducing dust exposures for those workers in jobs currently characterized by relatively high dust exposures.

Longwall Guidance and Control Development

NASA Technical Reports Server (NTRS)

1982-01-01

The longwall guidance and control (G&C) system was evaluated to determine which systems and subsystems lent themselves to automatic control in the mining of coal. The upper coal/shale interface was identified as the reference for a vertical G&C system, with two sensors (the natural backgound and the sensitized pick) being used to locate and track this boundary. In order to insure a relatively smooth recession surface (roof and floor of the excavated seam), a last and present cut measuring instrument (acoustic sensor) was used. Potentiometers were used to measure elevations of the shearer arms. The intergration of these components comprised the vertical control system (pitch control). Yaw and roll control were incorporated into a face alignment system which was designed to keep the coal face normal to its external boundaries. Numerous tests, in the laboratory and in the field, have confirmed the feasibility of automatic horizon control, as well as determining the face alignment.

Wetter and cooler: pronounced temperate climate conditions in western Anatolia during the Middle Miocene Climatic Optimum

NASA Astrophysics Data System (ADS)

Güner, Tuncay H.; Bouchal, Johannes M.; Köse, Nesibe; Denk, Thomas

2017-04-01

During the course of an ongoing palaeobotanical investigation of the lignite mines of the Yataǧan Basin, Muǧla province, Turkey, the fossil leaves of the Eskihisar lignite mine were analysed using the Climate Leaf Analysis Multivariate Program (CLAMP). The investigated fossil leaves derive from the marls and clayey limestones (Sekköy Member) overlying the exploited lignite seam (uppermost Turgut Member). The age of the studied sedimentary rocks is well constrained by vertebrate fossils occuring in the main lignite seam (MN6 → Gomphoterium angustidens Cuvier, 1817; Percrocuta miocenica Pavlov & Thenius, 1965) and at the Yenieskihisar Mammal locality (MN7/8, uppermost Sekköy Member). 719 specimens were measured and assigned to 65 leaf morphotypes. Using this data, CLAMP reconstructed the following climate parameters: mean annual temperature (MAT) 12.58 (+/-1.5)°C, warm month mean temperature (WMMT) 23.72 (+/-2.5)°C, cold month mean temperature (WMMT) 2.29 (+/-2)°C, length of growing season (LGS) 7.52 (+/-0.75) month, mean growing season precipitation (GSP) 130.1 (+/-40) cm, precipitation during the three wettest months (3-WET) 67 (+/-25) cm, precipitation during the three driest months (3-DRY) 20.4 (+/-7.5) cm. The reconstructed parameters are too cool for tropical climates (the 18˚ C winter isotherm being a threshold for tropical climates) and indicate temperate conditions; climates fitting these parameters (Cfb according to the Köppen-Geiger climate classification) can be found today in regions known as "Tertiary relict areas" (e.g. Black sea coast of Northeast Turkey, eastern China, Japan). Based on a substantial amount of rainfall during the three driest months, it is further possible to exclude markedly seasonal climates such as a summer-dry and winter-wet Mediterranean climate and a summer-wet and winter-dry monsoon climate as commonly found along the southern foothills of the Himalayas and in southwestern China. Instead, a fully humid Cf climate is proposed that has only a weak seasonality in precipitation (lower precipitation in winter). The findings of our study provide valuable information for inferring palaeoenvironments of middle Miocene rich ungulate faunas in western Turkey (e.g. Paşalar), for which seasonal tropical and subtropical forest communities have been proposed (Andrews, 1990). The fossil floras of the Tınaz and Salihpaşalar lignite mines, representing the Tınaz sub-basin and the main basin of the wider Yataǧan Basin, are investigated at the moment, and a synthesis paper combining and comparing evidence from the macro floral and palynological data is soon to be submitted. Andrews. (1990) Palaeoecology of the Miocene fauna from Paşalar, Turkey. Journal of Human evolution 19:569-582.

Investigation on localized corrosion of 304 stainless steel joints brazed using Sn-plated Ag alloy filler in NaCl aqueous solution

NASA Astrophysics Data System (ADS)

Wang, Xingxing; Li, Shuai; Peng, Jin

2018-03-01

Novel AgCuZnSn filler metal with high Sn contents was prepared from BAg50CuZn filler metal by a process of electroplating and thermal diffusion, and the prepared filler metal was applied to induction brazing of 304 stainless steel. The corrosion behavior of the brazed joints was evaluated based on localized corrosion analysis, the morphology of the joints were analyzed by SEM after immersion in a 3.5 vol% NaCl aqueous solution. The results indicated that corrosion groove occurred near the interface between the stainless steel base metal and the brazing seam. A wide range of defects such as holes and cracks appeared on the surface of the base metal, while the brazing seam zone almost no corrosion defects occur. With the increase of corrosion time, the corrosion rates of both the brazing seam and the base metal first exhibited an increasing trend, followed by a decreasing trend, and the corrosion rate of the base metal was slightly greater than that of the brazing seam. The corrosion potential of the brazing seam and 304 stainless steel were -0.7758 V and -0.7863 V, respectively.

Geochemistry of autochthonous and hypautochthonous siderite-dolomite coal-balls (Foord Seam, Bolsovian, Upper Carboniferous), Nova Scotia, Canada

USGS Publications Warehouse

Zodrow, E.L.; Lyons, P.C.; Millay, M.A.

1996-01-01

The 11-13 m thick Foord Seam in the fault-bounded Stellarton Basin, Nova Scotia, is the thickest seam from the Euramerican floral province known to contain coal-balls. In addition to the first discovery of autochthonous coal-balls in the Foord Seam, Nova Scotia, its shale parting also contains hypautochthonous coal-balls with histologically preserved plant structures. The coal-ball discovery helps fill a stratigraphic gap in coal-ball occurrences in the upper Carboniferous (Bolsovian) of Euramerica. The autochthonous and hypautochthonous coal-balls have a similar mineralogical composition and are composed of siderite (81-100%), dolomite-ankerite (0-19%), minor quartz and illite, and trace amounts of 'calcite'. Similar is also their permineralizing mineralogy, which consists of dolomite-ankerite and siderite. Their low pyrite content and carbonate mineralogy, and nonmarine origin, differentiates the Foord Seam coal-balls from other Euramerican coal-ball occurrences. A preliminary geochemical model, which is based on oxygen and carbon isotopic data, indicates that siderite in both the autochthonous and hypautochthonous coal-balls is of very early diagenetic (nonmarine) origin from 13C-enriched bicarbonate derived from bacterial methanogenesis of organic matter.

Palaeoenvironmental reconstruction of Hüsamlar coal seam, SW Turkey

NASA Astrophysics Data System (ADS)

Büçkün, Zeynep; İnaner, Hülya; Oskay, Riza Görkem; Christanis, Kimon

2015-06-01

The Ören and Yatağan Basins in SW Turkey host several Miocene coal deposits currently under exploitation for power generation. The present study aims to provide insight into the palaeoenvironmental conditions, which controlled the formation of the Hüsamlar coal seam located in Ören Basin. The coal seam displays many sharp alternations of matrix lignite beds and inorganic, lacustrine sediment layers. The coal is a medium-to-high ash lignite (10.47-31.16 wt%, on dry basis) with high total sulphur content (up to 10 wt%, on dry, ash-free basis), which makes it prone to self-combustion. The maceral composition indicates that the peat-forming vegetation consisted of both arboreal and herbaceous plants, with the latter being predominant in the upper part of the seam. Mica and feldspars contribute to the low part of the seam; carbonates are dominant in the upper part, whereas quartz and pyrite are present along the entire coal profile. The sudden transitions of the telmatic to the lacustrine regime and reverse is attributed to tectonic movements that controlled water table levels in the palaeomire, which affected surface runoff and hence, clastic deposition.

Overview of the influence of syn-sedimentary tectonics and palaeo-fluvial systems on coal seam and sand body characteristics in the Westphalian C strata, Campine Basin, Belgium

USGS Publications Warehouse

Dreesen, Roland; Bossiroy, Dominique; Dusar, Michiel; Flores, R.M.; Verkaeren, Paul; Whateley, M. K. G.; Spears, D.A.

1995-01-01

The Westphalian C strata found in the northeastern part of the former Belgian coal district (Campine Basin), which is part of an extensive northwest European paralic coal basin, are considered. The thickness and lateral continuity of the Westphalian C coal seams vary considerably stratigraphically and areally. Sedimentological facies analysis of borehole cores indicates that the deposition of Westphalian C coal-bearing strata was controlled by fluvial depositional systems whose architectures were ruled by local subsidence rates. The local subsidence rates may be related to major faults, which were intermittently reactivated during deposition. Lateral changes in coal seam groups are also reflected by marked variations of their seismic signatures. Westphalian C fluvial depositional systems include moderate to low sinuosity braided and anastomosed river systems. Stable tectonic conditions on upthrown, fault-bounded platforms favoured deposition by braided rivers and the associated development of relatively thick, laterally continuous coal seams in raised mires. In contrast, rapidly subsiding downthrown fault blocks favoured aggradation, probably by anastomosed rivers and the development of relatively thin, highly discontinuous coal seams in topogenous mires.

Coal Fires in the United States: A Case Study in Government Inattention

NASA Astrophysics Data System (ADS)

McCurdy, K. M.

2006-12-01

Coal fires occur in all coal producing nations. Like most other environmental problems fires are not confined by political boundaries. Important economic coal seams in the United States are found across the Inter-montaine west, the Midwest, and Appalachia. The age of these deposits differs, as does the grade and sulfur content of the coal, the mining techniques utilized for exploitation of this resource, and the markets in which the coal is traded. Coal fires are ordinary occurrences under extraordinary conditions. Every coal bed exposed in an underground or surface mine has the potential to ignite. These fires are spread thinly over the political geography and over time, so that constituencies rarely coalesce to petition government to address the coal fire problem. Coal fires produce serious problems with long term consequences for society. They threaten mine safety, consume a non-renewable resource, and produce toxic gases with serious health effects for local populations. Additionally, as coal production in the developing world intensifies, these problems worsen. The lack of government attention to coal fires is due to the confluence of at least four independent political factors: 1) The separated powers, federated system in which decisions in the United States are made; 2) Low levels of political energy available in Congress to be expended on coal fires, measured by the magnitude of legislative majorities and seniority; 3) The mid-twentieth century model of scientific and technical information moving indirectly to legislators through the bureaucratic agencies; 4) The chronic and diffuse nature of fires across space and time.

Geology of the Shinarump No. 1 uranium mine, Seven Mile Canyon area, Grand County, Utah

USGS Publications Warehouse

Finch, Warren Irvin

1954-01-01

The geology of the Shinarump No. 1 uranium mine, located about 12 miles northwest of Moab, Utah, in the Seven Mile Canyon area, Grand County, Utah, was studied to determine the habits, ore controls, and possible origin of the deposit. Rocks of Permian, Triassic, and Jurassic age crop out in the area mapped, and uranium deposits are found in three zones in the lower 25 feet of the Chinle formation of Late Triassic age. The Shinarump No. 1 mine, which is in the lowermost zone, is located on the west flank of the Moab anticline near the Moab fault. The Shinarump No. 1 uranium deposit consists of discontinuous lenticular layers of mineralized rock, irregular in outline, that, in general, follow the bedding. Ore minerals, mainly uraninite, impregnate the rock. High-grade ore seams of uraninite and chalcocite occur along bedding planes. Uraninite formed later than, or simultaneous with, most sulfides, and the chalcocite may be of two ages, with some being later than uraninite. Uraninite and chalcocite are concentrated in the more poorly sorted parts of siltstones. In the Seven Mile Canyon area guides to ore inferred from the study of the Shinarump No. 1 deposit are the presence of bleached siltstone, carbonaceous matter, and copper sulfides. Results of spectrographic analysis indicate that the mineralizing solutions contained important amounts of barium, vanadium, uranium, and copper, as well as lesser amounts of strontium, chromium, boron, yttrium, lead, and zinc. The origin of the Shinarump No. 1 deposit is thought to be hydrothermal.

Tracks Seam Like Airbags

NASA Image and Video Library

2004-01-28

Bearing a striking resemblance to a cluster of paper lanterns, these inflated airbags show a pattern of seams exactly like those left in the martian soil by the Mars Exploration Rover Opportunity during landing at Meridiani Planum, Mars.

Surface treatment using metal foil liner

NASA Technical Reports Server (NTRS)

Garvey, Ray

1989-01-01

A metal foil liner can be used to seal large area surfaces. Characteristics of the two-layer foil liner are discussed. Micrographs for foil-to-foil, foil-to-composite, visible seams, and hidden seams are examined.

Raising the Roof.

ERIC Educational Resources Information Center

Savage, John

2000-01-01

Discusses how the use of metal standing-seam roofs can help conserve energy, and with proper maintenance, be long-lasting. An example is given of one high school's replacement of their leaking roof with a metal standing-seam roof. (GR)

Development of signal processing algorithms for ultrasonic detection of coal seam interfaces

NASA Technical Reports Server (NTRS)

Purcell, D. D.; Ben-Bassat, M.

1976-01-01

A pattern recognition system is presented for determining the thickness of coal remaining on the roof and floor of a coal seam. The system was developed to recognize reflected pulse echo signals that are generated by an acoustical transducer and reflected from the coal seam interface. The flexibility of the system, however, should enable it to identify pulse-echo signals generated by radar or other techniques. The main difference being the specific features extracted from the recorded data as a basis for pattern recognition.

Potential minability and economic viability of the Antaramut-Kurtan-Dzoragukh coal field, north-central Armenia; a prefeasibility study

USGS Publications Warehouse

Huber, Douglas W.; Pierce, Brenda S.

2000-01-01

The U. S. Geological Survey (USGS) conducted a coal resource assessment of several areas in Armenia from 1997 to 1999. This report, which presents a prefeasibility study of the economic and mining potential of one coal deposit found and studied by the USGS team, was prepared using all data available at the time of the study and the results of the USGS exploratory work, including core drilling, trenching, coal quality analyses, and other ongoing field work. On the basis of information currently available, it is the authors? opinion that a small surface coal mine having about a 20-year life span could be developed in the Antaramut-Kurtan-Dzoragukh coal field, specifically at the Dzoragukh site. The mining organization selected or created to establish the mine will need to conduct necessary development drilling and other work to establish the final feasibility study for the mine. The company will need to be entrepreneurial, profit oriented, and sensitive to the coal consumer; have an analytical management staff; and focus on employee training, safety, and protection of the environment. It is anticipated that any interested parties will be required to submit detailed mining plans to the appropriate Armenian Government agencies. Further development work will be required to reach a final decision regarding the economic feasibility of the mine. However, available information indicates that a small, economic surface mine can be developed at this locality. The small mine suggested is a typical surface-outcropstripping, contour mining operation. In addition, auger mining is strongly suggested, because the recovery of these low-cost mining reserves will help to ensure that the operation will be a viable, economic enterprise. (Auger mining is a system in which large-diameter boreholes are placed horizontally into the coal seam at the final highwall set as the economic limit for the surface mining operation). A special horizontal boring machine, which can be imported from Russia, is required for auger mining. Although auger-mining coal reserves do exist, the necessary development work will further verify the extent of these reserves and all of the other indicated reserves. The following items are based on the detailed study reported in this publication. Initial investment.?Following an investment of US $85,000 over a 12-month period in mine development drilling and other activities, a decision must be taken regarding further investment in an ongoing mining operation. If the new data support the opening of the surface mine, __________________________ 1Consultant, 6024 Morning Dew Drive, Austin, TX 78749. 2 U.S. Geological Survey, 956 National Center, Reston, VA 20192 1 2 MINABILITY AND ECONOMIC VIABILITY, ANTARAMUT-KURTAN-DZORAGUKH COAL FIELD the $85,000 development cost is amortized over the first 10 years of mine production. If the new data do not support the opening of the mine, the $85,000 is considered a business development expense that may be written off against profits from other operations for income or other tax purposes or simply as a business loss. Total capital required.?The equipment costs will reach a total of $900,500 which will be amortized over a 7-year period to establish estimated coal mining costs. Estimated working capital costs are $300,000, which will be borrowed. Surface mining reserves.?Approximately 840,200 metric tonnes of surface minable coal reserves at 9.3 m3 of overburden per metric tonne of minable coal is indicated. Recovery of the minable coal at 85 percent will yield 714,000 recoverable metric tonnes of marketable as-mined coal. Auger mining reserves.?Auger-mining reserves of 576,000 metric tonnes are indicated. Recoverable auger-mining reserves of 202,000 metric tonnes (at 35-percent recovery) can be expected. Auger-mining production will vary according to the hole size being used, but, in either case, augering is a very profitable addition to the mining oper

10. DETAIL VIEW OF SIDEWALK RAILING, SHOWING WELDED SEAM, 'ILLINOISSUSA' ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

10. DETAIL VIEW OF SIDEWALK RAILING, SHOWING WELDED SEAM, 'ILLINOIS-S-USA' ROLLER MARK, AND WELDER'S INITIALS ('C.K.'), LOOKING NORTH-NORTHWEST Harms - Benton Street Bridge, Spanning Iowa River at Benton Street, Iowa City, Johnson County, IA

SOURCE WATER CONTROL WITHIN THE MARY MURPHY MINE

EPA Science Inventory

The Mary Murphy mine is located in Chaffee County, Colorado, approximately 12 miles southwest from Buena Vista in the San Isabel National Forest.. The mine drains water from multiple portals into Chalk Creek; this mine water contains elevated levels of zinc and cadmium which exce...

Laser-welded Dissimilar Steel-aluminum Seams for Automotive Lightweight Construction

NASA Astrophysics Data System (ADS)

Schimek, M.; Springer, A.; Kaierle, S.; Kracht, D.; Wesling, V.

By reducing vehicle weight, a significant increase in fuel efficiency and consequently a reduction in CO 2 emissions can be achieved. Currently a high interest in the production of hybrid weld seams between steel and aluminum exists. Previous methods as laser brazing are possible only by using fluxes and additional materials. Laser welding can be used to join steel and aluminum without the use of additives. With a low penetration depth increases in tensile strength can be achieved. Recent results from laser welded overlap seams show that there is no compromise in strength by decreasing penetration depth in the aluminum.

CO2 sequestration potential of Charqueadas coal field in Brazil

DOE Office of Scientific and Technical Information (OSTI.GOV)

Romanov, V; Santarosa, C; Crandall, D

2013-02-01

Although coal is not the primary source of energy in Brazil there is growing interest to evaluate the potential of coal from the south of the country for various activities. The I2B coal seamin the Charqueadas coal field has been considered a target for enhanced coal bed methane production and CO2 sequestration. A detailed experimental study of the samples from this seam was conducted at the NETL with assistance from the Pontif?cia Universidade Cat?lica Do Rio Grande Do Sul. Such properties as sorption capacity, internal structure of the samples, porosity and permeability were of primary interest in this characterization study.more » The samples used were low rank coals (high volatile bituminous and sub-bituminous) obtained from the I2B seam. It was observed that the temperature effect on adsorption capacity correlates negatively with as-received water and mineral content. Langmuir CO2 adsorption capacity of the coal samples ranged 0.61?2.09 mmol/g. The upper I2B seam appears to be overall more heterogeneous and less permeable than the lower I2B seam. The lower seam coal appears to have a large amount of micro-fractures that do not close even at 11 MPa of confining pressure.« less

Numerical investigations on mapping permeability heterogeneity in coal seam gas reservoirs using seismo-electric methods

NASA Astrophysics Data System (ADS)

Gross, L.; Shaw, S.

2016-04-01

Mapping the horizontal distribution of permeability is a key problem for the coal seam gas industry. Poststack seismic data with anisotropy attributes provide estimates for fracture density and orientation which are then interpreted in terms of permeability. This approach delivers an indirect measure of permeability and can fail if other sources of anisotropy (for instance stress) come into play. Seismo-electric methods, based on recording the electric signal from pore fluid movements stimulated through a seismic wave, measure permeability directly. In this paper we use numerical simulations to demonstrate that the seismo-electric method is potentially suitable to map the horizontal distribution of permeability changes across coal seams. We propose the use of an amplitude to offset (AVO) analysis of the electrical signal in combination with poststack seismic data collected during the exploration phase. Recording of electrical signals from a simple seismic source can be closer to production planning and operations. The numerical model is based on a sonic wave propagation model under the low frequency, saturated media assumption and uses a coupled high order spectral element and low order finite element solver. We investigate the impact of seam thickness, coal seam layering, layering in the overburden and horizontal heterogeneity of permeability.

Water budgets and groundwater volumes for abandoned underground mines in the Western Middle Anthracite Coalfield, Schuylkill, Columbia, and Northumberland Counties, Pennsylvania-Preliminary estimates with identification of data needs

USGS Publications Warehouse

Goode, Daniel J.; Cravotta, Charles A.; Hornberger, Roger J.; Hewitt, Michael A.; Hughes, Robert E.; Koury, Daniel J.; Eicholtz, Lee W.

2011-01-01

This report, prepared in cooperation with the Pennsylvania Department of Environmental Protection (PaDEP), the Eastern Pennsylvania Coalition for Abandoned Mine Reclamation, and the Dauphin County Conservation District, provides estimates of water budgets and groundwater volumes stored in abandoned underground mines in the Western Middle Anthracite Coalfield, which encompasses an area of 120 square miles in eastern Pennsylvania. The estimates are based on preliminary simulations using a groundwater-flow model and an associated geographic information system that integrates data on the mining features, hydrogeology, and streamflow in the study area. The Mahanoy and Shamokin Creek Basins were the focus of the study because these basins exhibit extensive hydrologic effects and water-quality degradation from the abandoned mines in their headwaters in the Western Middle Anthracite Coalfield. Proposed groundwater withdrawals from the flooded parts of the mines and stream-channel modifications in selected areas have the potential for altering the distribution of groundwater and the interaction between the groundwater and streams in the area. Preliminary three-dimensional, steady-state simulations of groundwater flow by the use of MODFLOW are presented to summarize information on the exchange of groundwater among adjacent mines and to help guide the management of ongoing data collection, reclamation activities, and water-use planning. The conceptual model includes high-permeability mine voids that are connected vertically and horizontally within multicolliery units (MCUs). MCUs were identified on the basis of mine maps, locations of mine discharges, and groundwater levels in the mines measured by PaDEP. The locations and integrity of mine barriers were determined from mine maps and groundwater levels. The permeability of intact barriers is low, reflecting the hydraulic characteristics of unmined host rock and coal. A steady-state model was calibrated to measured groundwater levels and stream base flow, the latter at many locations composed primarily of discharge from mines. Automatic parameter estimation used MODFLOW-2000 with manual adjustments to constrain parameter values to realistic ranges. The calibrated model supports the conceptual model of high-permeability MCUs separated by low-permeability barriers and streamflow losses and gains associated with mine infiltration and discharge. The simulated groundwater levels illustrate low groundwater gradients within an MCU and abrupt changes in water levels between MCUs. The preliminary model results indicate that the primary result of increased pumping from the mine would be reduced discharge from the mine to streams near the pumping wells. The intact barriers limit the spatial extent of mine dewatering. Considering the simulated groundwater levels, depth of mining, and assumed bulk porosity of 11 or 40 percent for the mined seams, the water volume in storage in the mines of the Western Middle Anthracite Coalfield was estimated to range from 60 to 220 billion gallons, respectively. Details of the groundwater-level distribution and the rates of some mine discharges are not simulated well using the preliminary model. Use of the model results should be limited to evaluation of the conceptual model and its simulation using porous-media flow methods, overall water budgets for the Western Middle Anthracite Coalfield, and approximate storage volumes. Model results should not be considered accurate for detailed simulation of flow within a single MCU or individual flooded mine. Although improvements in the model calibration were possible by introducing spatial variability in permeability parameters and adjusting barrier properties, more detailed parameterizations have increased uncertainty because of the limited data set. The preliminary identification of data needs includes continuous streamflow, mine discharge rate, and groundwater levels in the mines and adjacent areas. Data collected whe

Chemokine Signaling during Midline Epithelial Seam Disintegration Facilitates Palatal Fusion

PubMed Central

Suttorp, Christiaan M.; Cremers, Niels A.; van Rheden, René; Regan, Raymond F.; Helmich, Pia; van Kempen, Sven; Kuijpers-Jagtman, Anne M.; Wagener, Frank A.D.T.G.

2017-01-01

Disintegration of the midline epithelial seam (MES) is crucial for palatal fusion, and failure results in cleft palate. Palatal fusion and wound repair share many common signaling pathways related to epithelial-mesenchymal cross-talk. We postulate that chemokine CXCL11, its receptor CXCR3, and the cytoprotective enzyme heme oxygenase (HO), which are crucial during wound repair, also play a decisive role in MES disintegration. Fetal growth restriction and craniofacial abnormalities were present in HO-2 knockout (KO) mice without effects on palatal fusion. CXCL11 and CXCR3 were highly expressed in the disintegrating MES in both wild-type and HO-2 KO animals. Multiple apoptotic DNA fragments were present within the disintegrating MES and phagocytized by recruited CXCR3-positive wt and HO-2 KO macrophages. Macrophages located near the MES were HO-1-positive, and more HO-1-positive cells were present in HO-2 KO mice compared to wild-type. This study of embryonic and palatal development provided evidence that supports the hypothesis that the MES itself plays a prominent role in palatal fusion by orchestrating epithelial apoptosis and macrophage recruitment via CXCL11-CXCR3 signaling. PMID:29164113

Method and apparatus for monitoring the thickness of a coal rib during rib formation

DOEpatents

Mowrey, Gary L.; Ganoe, Carl W.; Monaghan, William D.

1996-01-01

Apparatus for monitoring the position of a mining machine cutting a new entry in a coal seam relative to an adjacent, previously cut entry to determine the distance between a near face of the adjacent previously cut entry and a new face adjacent thereto of a new entry being cut by the mining machine which together define the thickness of a coal rib being formed between the new entry and the adjacent previously cut entry during the new entry-cutting operation. The monitoring apparatus; includes a transmit antenna mounted on the mining machine and spaced inwardly from the new face of the coal rib for transmitting radio energy towards the coal rib so that one portion of the radio energy is reflected by the new face which is defined at an air-coal interface between the new entry and the coal rib and another portion of the radio energy is reflected by the near face of the coal rib which is defined at an air-coal interface between the coal rib and the adjacent previously cut entry. A receive antenna mounted on the mining machine and spaced inwardly of the new face of the coal rib receives the one portion of the radio energy reflected by the new face and also receives the another portion of the radio energy reflected by the near face. A processor determines a first elapsed time period equal to the time required for the one portion of the radio energy reflected by the new face to travel between the transmit antenna and the receive antenna and also determines a second elapsed time period equal to the time required for the another portion of the radio energy reflected by the near face to travel between the transmit antenna and the receive antenna and thereafter calculates the thickness of the coal rib being formed as a function of the difference between the first and second elapsed time periods.

Heavy Metal.

ERIC Educational Resources Information Center

Shoemaker, W. Lee

1998-01-01

Discusses the advantages, both functional and economic, of using a standing-seam metal roof in both new roof installations and reroofing projects of educational facilities. Structural versus non-structural standing-seam roofs are described as are the types of insulation that can be added and roof finishes used. (GR)

Capacitive system detects and locates fluid leaks

NASA Technical Reports Server (NTRS)

1966-01-01

Electronic monitoring system automatically detects and locates minute leaks in seams of large fluid storage tanks and pipelines covered with thermal insulation. The system uses a capacitive tape-sensing element that is adhesively bonded over seams where fluid leaks are likely to occur.

PROCEEDINGS OF THE WORKSHOP GEOMEMBRANE SEAMING: DATA ACQUISITION AND CONTROL

EPA Science Inventory

The U.S. Environmental Protection Agency's Risk Reduction Engineering Laboratory, in cooperation with the Geosynthetic Research Institute, sponsored a workshop on Geomembrane Wedge Welding Seaming: ata Acquisition and Control on April 22, 1993. he workshop was held at the Andrew ...

Report: Ombudsman Review of the Marjol Battery Site, Throop, Pennsylvania

EPA Pesticide Factsheets

Report #2004-P-00017, May 18, 2004. Over-excavating the Five Foot Seam and ensuring a reliable noncombustible barrier is established between the Five Foot Seam and the Battery Casing Material will sufficiently ensure the long-term safety of the Site.

Science priorities for seamounts: research links to conservation and management.

PubMed

Clark, Malcolm R; Schlacher, Thomas A; Rowden, Ashley A; Stocks, Karen I; Consalvey, Mireille

2012-01-01

Seamounts shape the topography of all ocean basins and can be hotspots of biological activity in the deep sea. The Census of Marine Life on Seamounts (CenSeam) was a field program that examined seamounts as part of the global Census of Marine Life (CoML) initiative from 2005 to 2010. CenSeam progressed seamount science by collating historical data, collecting new data, undertaking regional and global analyses of seamount biodiversity, mapping species and habitat distributions, challenging established paradigms of seamount ecology, developing new hypotheses, and documenting the impacts of human activities on seamounts. However, because of the large number of seamounts globally, much about the structure, function and connectivity of seamount ecosystems remains unexplored and unknown. Continual, and potentially increasing, threats to seamount resources from fishing and seabed mining are creating a pressing demand for research to inform conservation and management strategies. To meet this need, intensive science effort in the following areas will be needed: 1) Improved physical and biological data; of particular importance is information on seamount location, physical characteristics (e.g. habitat heterogeneity and complexity), more complete and intensive biodiversity inventories, and increased understanding of seamount connectivity and faunal dispersal; 2) New human impact data; these shall encompass better studies on the effects of human activities on seamount ecosystems, as well as monitoring long-term changes in seamount assemblages following impacts (e.g. recovery); 3) Global data repositories; there is a pressing need for more comprehensive fisheries catch and effort data, especially on the high seas, and compilation or maintenance of geological and biodiversity databases that underpin regional and global analyses; 4) Application of support tools in a data-poor environment; conservation and management will have to increasingly rely on predictive modelling techniques, critical evaluation of environmental surrogates as faunal "proxies", and ecological risk assessment.

Criteria to aid in the establishment of genetic boundaries within a carboniferous basin: Mary Lee Coal Zone, Black Warrior Basin, Alabama

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bryant, T.W.; Gastaldo, R.A.

The upper part of the Mary Lee coal zone of the Lower Pennsylvanian (Westphalian A) Pottsville Formation in northwestern Alabama is composed of the Mary Lee and the Newcastle coal seams. The Mary Lee coal seam has been economically significant in terms of both mining and coal-bed methane production. A sedimentological, paleontological, and geochemical investigation of the lithologies associated with this coal zone was done to define the changes that occur in facies changing from terrestrial into marine facies. A ravinement bed, ranging in thickness from 13.0 deposits. Fifteen surficially exposed sections were observed and sampled in the study area.more » Geochemical analyses were done on samples collected from seven sections along the perimeter of the study area. The analyses conducted involved inductively coupled atomic plasma spectrometry (ICAP) for seven elemental oxides that include aluminum, iron, silica, calcium, potassium, magnesium and manganese. Atomic absorption was used to determine sodium content. Carbonate carbon was determined by weight percent difference after hydrochloric acid treatment, whereas organic carbon content was determined by use of a carbon analyzer on a LECO[sup TM] induction furnace. Sulfur content was also determined by a LECO induction furnace equipped with a sulfur analyzer. Loss-on-ignition (LOI) percentage was based upon change in weight of samples after a period of 30 min in a muffle furnace at a temperature of 1000[degrees]C. The combination of sedimentological, paleontological, and geochemical characteristics were used to better understand the depositional setting of the upper Mary Lee coal zone in terms of a transgressive event. These criteria can be used in similar basin systems to better understand the depositional history of those settings.« less

Flow in Coal Seams: An Unconventional Challenge

NASA Astrophysics Data System (ADS)

Armstrong, R. T.; Mostaghimi, P.; Jing, Y.; Gerami, A.

2016-12-01

A significant unconventional resource for energy is the methane gas stored in shallow coal beds, known as coal seam gas. An integrated imaging and modelling framework is developed for analysing petrophysical behaviour of coals. X-ray micro-computed tomography (micro-CT) is applied using a novel contrast agent method for visualising micrometer-sized fractures in coal. The technique allows for the visualisation of coal features not visible with conventional imaging methods. A Late Permian medium volatile bituminous coal from Moura Coal Mine (Queensland, Australia) is imaged and the resulting three-dimensional coal fracture system is extracted for fluid flow simulations. The results demonstrate a direct relationship between coal lithotype and permeability. Scanning electron microscope and energy dispersive spectrometry (SEM-EDS) together with X-ray diffraction (XRD) methods are used for identifying mineral matters at high resolution. SEM high-resolution images are also used to calibrate the micro-CT images and measure the exact aperture size of fractures. This leads to a more accurate estimation of permeability using micro-CT images. To study the significance of geometry and topology of the fracture system, a fracture reconstruction method based on statistical properties of coal is also developed. The network properties including the frequency, aperture size distribution, length, and spacing of the imaged coal fracture system. This allows for a sensitivity analysis on the effects that coal fracture topology and geometry has on coal petrophysical properties. Furthermore, we generate microfluidic chips based on coal fracture observations. The chip is used for flow experiments to visualise multi-fluid processes and measure recovery of gas. A combined numerical and experimental approach is applied to obtain relative permeability curves for different regions of interest. A number of challenges associated with coal samples are discussed and insights are provided for better understanding of these complex porous media systems.

Coalbed methane-produced water quality and its management options in Raniganj Basin, West Bengal, India

NASA Astrophysics Data System (ADS)

Mendhe, Vinod Atmaram; Mishra, Subhashree; Varma, Atul Kumar; Singh, Awanindra Pratap

2017-06-01

Coalbed methane (CBM) recovery is associated with production of large quantity of groundwater. The coal seams are depressurized by pumping of water for regular and consistent gas production. Usually, CBM operators need to pump >10 m3 of water per day from one well, which depends on the aquifer characteristics, drainage and recharge pattern. In India, 32 CBM blocks have been awarded for exploration and production, out of which six blocks are commercially producing methane gas at 0.5 million metric standard cubic feet per day. Large amount of water is being produced from CBM producing blocks, but no specific information or data are available for geochemical properties of CBM-produced water and its suitable disposal or utilization options for better management. CBM operators are in infancy and searching for the suitable solutions for optimal management of produced water. CBM- and mine-produced water needs to be handled considering its physical and geochemical assessment, because it may have environmental as well as long-term impact on aquifer. Investigations were carried out to evaluate geochemical and hydrogeological conditions of CBM blocks in Raniganj Basin. Totally, 15 water samples from CBM well head and nine water samples from mine disposal head were collected from Raniganj Basin. The chemical signature of produced water reveals high sodium and bicarbonate concentrations with low calcium and magnesium, and very low sulphate in CBM water. It is comprehend that CBM water is mainly of Na-HCO3 type and coal mine water is of Ca-Mg-SO4 and HCO3-Cl-SO4 type. The comparative studies are also carried out for CBM- and mine-produced water considering the geochemical properties, aquifer type, depth of occurrence and lithological formations. Suitable options like impounding, reverse osmosis, irrigation and industrial use after prerequisite treatments are suggested. However, use of this huge volume of CBM- and mine-produced water for irrigation or other beneficial purposes may require careful management based on water pH, EC, TDS, alkalinity, bicarbonate, sodium, fluoride, metals content and SAR values.

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

NASA Astrophysics Data System (ADS)

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 source within their zone of influence, paths may develop and allow methane movement towards sealed or active gobs under pressure differentials. Knowledge gained from this research will better prepare mine operations for potential methane inflows, thus improving mine safety.

Identification of Wnt Pathway Target Genes Regulating the Division and Differentiation of Larval Seam Cells and Vulval Precursor Cells in Caenorhabditis elegans

PubMed Central

Gorrepati, Lakshmi; Krause, Michael W.; Chen, Weiping; Brodigan, Thomas M.; Correa-Mendez, Margarita; Eisenmann, David M.

2015-01-01

The evolutionarily conserved Wnt/β-catenin signaling pathway plays a fundamental role during metazoan development, regulating numerous processes including cell fate specification, cell migration, and stem cell renewal. Wnt ligand binding leads to stabilization of the transcriptional effector β-catenin and upregulation of target gene expression to mediate a cellular response. During larval development of the nematode Caenorhabditis elegans, Wnt/β-catenin pathways act in fate specification of two hypodermal cell types, the ventral vulval precursor cells (VPCs) and the lateral seam cells. Because little is known about targets of the Wnt signaling pathways acting during larval VPC and seam cell differentiation, we sought to identify genes regulated by Wnt signaling in these two hypodermal cell types. We conditionally activated Wnt signaling in larval animals and performed cell type–specific "mRNA tagging" to enrich for VPC and seam cell–specific mRNAs, and then used microarray analysis to examine gene expression compared to control animals. Two hundred thirty-nine genes activated in response to Wnt signaling were identified, and we characterized 50 genes further. The majority of these genes are expressed in seam and/or vulval lineages during normal development, and reduction of function for nine genes caused defects in the proper division, fate specification, fate execution, or differentiation of seam cells and vulval cells. Therefore, the combination of these techniques was successful at identifying potential cell type–specific Wnt pathway target genes from a small number of cells and at increasing our knowledge of the specification and behavior of these C. elegans larval hypodermal cells. PMID:26048561

Identification of Wnt Pathway Target Genes Regulating the Division and Differentiation of Larval Seam Cells and Vulval Precursor Cells in Caenorhabditis elegans.

PubMed

Gorrepati, Lakshmi; Krause, Michael W; Chen, Weiping; Brodigan, Thomas M; Correa-Mendez, Margarita; Eisenmann, David M

2015-06-05

The evolutionarily conserved Wnt/β-catenin signaling pathway plays a fundamental role during metazoan development, regulating numerous processes including cell fate specification, cell migration, and stem cell renewal. Wnt ligand binding leads to stabilization of the transcriptional effector β-catenin and upregulation of target gene expression to mediate a cellular response. During larval development of the nematode Caenorhabditis elegans, Wnt/β-catenin pathways act in fate specification of two hypodermal cell types, the ventral vulval precursor cells (VPCs) and the lateral seam cells. Because little is known about targets of the Wnt signaling pathways acting during larval VPC and seam cell differentiation, we sought to identify genes regulated by Wnt signaling in these two hypodermal cell types. We conditionally activated Wnt signaling in larval animals and performed cell type-specific "mRNA tagging" to enrich for VPC and seam cell-specific mRNAs, and then used microarray analysis to examine gene expression compared to control animals. Two hundred thirty-nine genes activated in response to Wnt signaling were identified, and we characterized 50 genes further. The majority of these genes are expressed in seam and/or vulval lineages during normal development, and reduction of function for nine genes caused defects in the proper division, fate specification, fate execution, or differentiation of seam cells and vulval cells. Therefore, the combination of these techniques was successful at identifying potential cell type-specific Wnt pathway target genes from a small number of cells and at increasing our knowledge of the specification and behavior of these C. elegans larval hypodermal cells. Copyright © 2015 Gorrepati et al.

Interestingness measures and strategies for mining multi-ontology multi-level association rules from gene ontology annotations for the discovery of new GO relationships.

PubMed

Manda, Prashanti; McCarthy, Fiona; Bridges, Susan M

2013-10-01

The Gene Ontology (GO), a set of three sub-ontologies, is one of the most popular bio-ontologies used for describing gene product characteristics. GO annotation data containing terms from multiple sub-ontologies and at different levels in the ontologies is an important source of implicit relationships between terms from the three sub-ontologies. Data mining techniques such as association rule mining that are tailored to mine from multiple ontologies at multiple levels of abstraction are required for effective knowledge discovery from GO annotation data. We present a data mining approach, Multi-ontology data mining at All Levels (MOAL) that uses the structure and relationships of the GO to mine multi-ontology multi-level association rules. We introduce two interestingness measures: Multi-ontology Support (MOSupport) and Multi-ontology Confidence (MOConfidence) customized to evaluate multi-ontology multi-level association rules. We also describe a variety of post-processing strategies for pruning uninteresting rules. We use publicly available GO annotation data to demonstrate our methods with respect to two applications (1) the discovery of co-annotation suggestions and (2) the discovery of new cross-ontology relationships. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.

49 CFR 230.72 - Testing main reservoirs.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., DEPARTMENT OF TRANSPORTATION STEAM LOCOMOTIVE INSPECTION AND MAINTENANCE STANDARDS Steam Locomotives and... longitudinal lap seams, an appropriate NDE method that can measure the wall thickness of the reservoir may be... or riveted longitudinal lap seam main reservoirs, an appropriate NDE method that can measure wall...

Airbag Seams Leave Trails

NASA Technical Reports Server (NTRS)

2004-01-01

This image taken by the Mars Exploration Rover Opportunity's panoramic camera shows where the rover's airbag seams left impressions in the martian soil. The drag marks were made after the rover successfully landed at Meridiani Planum and its airbags were retracted. The rover can be seen in the foreground.

Research on the welding process of aluminum alloy based on high power fiber laser

NASA Astrophysics Data System (ADS)

Zhang, Jian; Zhang, Wei; Pan, Xiaoming; Huang, Shanshi; Liu, Wenwen

2017-08-01

To research the formation and variation principle of the weld seam and molten pool for aluminum alloy high power fiber laser welding, the welding experiments for 5052 aluminum alloy were carried out. The influences of laser power, scanning velocity and protection gas on the welding process were systematically researched. The results show that with the increase of power and scanning velocity, the depth to width ratio first increases and then decreases. The ratio reaches the maximum value at 2.6 KW and 30 mm/s, respectively. When the power located at 2.6 KW to 2.8 KW or the velocity located at 25 mm/s to 30 mm/s, stable deep penetration welding can be obtained. The weld seam shows relative flat appearance and the molten pool presents typical "T shape" topography. Moreover, the protection gas also influences the appearance of the weld seam. Using the independently designed fixture, the quality of the weld seam can be well improved.

Characteristics of Extra Narrow Gap Weld of HSLA Steel Welded by Single-Seam per Layer Pulse Current GMA Weld Deposition

NASA Astrophysics Data System (ADS)

Agrawal, B. P.; Ghosh, P. K.

2017-03-01

Butt weld joints are produced using pulse current gas metal arc welding process by employing the technique of centrally laid multi-pass single-seam per layer weld deposition in extra narrow groove of thick HSLA steel plates. The weld joints are prepared by using different combination of pulse parameters. The selection of parameter of pulse current gas metal arc welding is done considering a summarized influence of simultaneously interacting pulse parameters defined by a dimensionless hypothetical factor ϕ. The effect of diverse pulse parameters on the characteristics of weld has been studied. Weld joint is also prepared by using commonly used multi-pass multi-seam per layer weld deposition in conventional groove. The extra narrow gap weld joints have been found much superior to the weld joint prepared by multi-pass multi-seam per layer deposition in conventional groove with respect to its metallurgical characteristics and mechanical properties.

Relations between coal petrology and gas content in the Upper Newlands Seam, Central Queensland, Australia

USGS Publications Warehouse

Walker, R.; Glikson, M.; Mastalerz, Maria

2001-01-01

The Upper Newlands Seam in the northern Bowen Basin, Queensland Australia consists of six benches (A-F) that have different petrographic assemblages. Benches C and E contain relatively abundant inertodetrinite and mineral matter, as well as anomalously high reflectance values; these characteristics support a largely allochthonous, detrital origin for the C and E benches. Fractures and cleats in the seam show a consistent orientation of northeast-southwest for face cleats, and a wide range of orientations for fractures. Cleat systems are well developed in bright bands, with poor continuity in the dull coal. Both maceral content and cleat character are suggested to influence gas drainage in the upper Newlands Seam. A pronounced positive correlation between vitrinite abundance and gas desorption data suggests more efficient drainage from benches with abundant vitrinite. Conversely, inertinite-rich benches are suggested to have less efficient drainage, and possibly retain gas within pore spaces, which could increase the outburst potential of the coal. ?? 2001 Elsevier Science B.V. All rights reserved.

Process characteristics of the combination of laser beam- and gas metal arc welding

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kalla, G.; Neuenhahn, J.; Koerber, C.

1994-12-31

In this presentation, experiences regarding the combination of laser beam-and gas metal arc welding are discussed. The combination of both techniques offers the possibility of using the specific advantages include the deep penetration effect and the concentrated heat input. Additionally, the gas metal arc welding (GMAW) process is characterized by several advantages, such as high thermal efficiency and good gap-bridging ability. Beyond these characteristics, the combination leads to additional advantages concerning process, technique, and quality. Improvement of seam quality and properties are of special note. Adaptation of the GMAW parameters reduces the hardness of the seam weld at increasing weldingmore » speed. This is possible by adapting the efficiency of metal deposition and by the suitable choice of wire material composition. Another advantage is an improvement of surface topology. The surface of the weld seam and the connection to the base material are very smooth. This leads to advantages with regard to the fatigue strength of the seam.« less

Two consecutive microtubule-based epithelial seaming events mediate dorsal closure in the scuttle fly Megaselia abdita.

PubMed

Fraire-Zamora, Juan Jose; Jaeger, Johannes; Solon, Jérôme

2018-03-14

Evolution of morphogenesis is generally associated with changes in genetic regulation. Here, we report evidence indicating that dorsal closure, a conserved morphogenetic process in dipterans, evolved as the consequence of rearrangements in epithelial organization rather than signaling regulation. In Drosophila melanogaster , dorsal closure consists of a two-tissue system where the contraction of extraembryonic amnioserosa and a JNK/Dpp-dependent epidermal actomyosin cable result in microtubule-dependent seaming of the epidermis. We find that dorsal closure in Megaselia abdita, a three-tissue system comprising serosa, amnion and epidermis, differs in morphogenetic rearrangements despite conservation of JNK/Dpp signaling. In addition to an actomyosin cable, M. abdita dorsal closure is driven by the rupture and contraction of the serosa and the consecutive microtubule-dependent seaming of amnion and epidermis. Our study indicates that the evolutionary transition to a reduced system of dorsal closure involves simplification of the seaming process without changing the signaling pathways of closure progression. © 2018, Fraire-Zamora et al.

Two consecutive microtubule-based epithelial seaming events mediate dorsal closure in the scuttle fly Megaselia abdita

PubMed Central

Jaeger, Johannes

2018-01-01

Evolution of morphogenesis is generally associated with changes in genetic regulation. Here, we report evidence indicating that dorsal closure, a conserved morphogenetic process in dipterans, evolved as the consequence of rearrangements in epithelial organization rather than signaling regulation. In Drosophila melanogaster, dorsal closure consists of a two-tissue system where the contraction of extraembryonic amnioserosa and a JNK/Dpp-dependent epidermal actomyosin cable result in microtubule-dependent seaming of the epidermis. We find that dorsal closure in Megaselia abdita, a three-tissue system comprising serosa, amnion and epidermis, differs in morphogenetic rearrangements despite conservation of JNK/Dpp signaling. In addition to an actomyosin cable, M. abdita dorsal closure is driven by the rupture and contraction of the serosa and the consecutive microtubule-dependent seaming of amnion and epidermis. Our study indicates that the evolutionary transition to a reduced system of dorsal closure involves simplification of the seaming process without changing the signaling pathways of closure progression. PMID:29537962

Simulation of Double-Seaming in a Two-piece Aluminum Can

NASA Astrophysics Data System (ADS)

Romanko, Anne; Berry, Dale; Fox, David

2004-06-01

The aluminum can industry in the United States and Canada manufactures over 100 billion cans per year. Two-piece aluminum cans are commonly used to seal and deliver foodstuffs such as soft drinks, beer, pet food, and other perishable items. In order to ensure product safety and performance, the double seam between the can body and lid is a critical component of the package. Double-seaming is a method by which the flange of the can body and the curl of the end are folded over together such that the final joint is composed of five metal thicknesses. There are a number of design challenges involved with the art of double seaming, especially with the push to lightweight. Although the requirements vary by product, the typical beer package must be able to hold pressures in excess of 90psi. In addition, in production, double seaming is a high-speed operation with speeds as high as 3000 cans/minute on an 18-spindle seamer. For this high volume, low cost industry, understanding and optimizing the seaming process can advance the industry as well as help prevent various manufacturing problems that produce a poor seal between the two pieces of the can. To aid in understanding the mechanics of the can parts during double-seaming, a simulation procedure was developed and carried out on a 202 diameter beverage can and lid. Simulations were run with the explicit dynamics solver ABAQUS/Explicit using the continuum shell element technology available in the ABAQUS general purpose FEA program. The continuum shell is a shear-deformable shell element with the topology of an eight node brick. The element's formulation allows continuously varying, solution-dependent shell thickness and through-thickness pinching stress. One important advantage of using the continuum shell as opposed to a traditional shell element is that true contact interactions at the top and bottom surfaces of the can body and lid can be accurately modeled. With a conventional shell element, contact is performed at the shell mid-surface or at an offset point representing where the top or bottom surface is expected to be. This paper discusses this new simulation technique and provides an example of its use.

Fuzzy linear model for production optimization of mining systems with multiple entities

NASA Astrophysics Data System (ADS)

Vujic, Slobodan; Benovic, Tomo; Miljanovic, Igor; Hudej, Marjan; Milutinovic, Aleksandar; Pavlovic, Petar

2011-12-01

Planning and production optimization within multiple mines or several work sites (entities) mining systems by using fuzzy linear programming (LP) was studied. LP is the most commonly used operations research methods in mining engineering. After the introductory review of properties and limitations of applying LP, short reviews of the general settings of deterministic and fuzzy LP models are presented. With the purpose of comparative analysis, the application of both LP models is presented using the example of the Bauxite Basin Niksic with five mines. After the assessment, LP is an efficient mathematical modeling tool in production planning and solving many other single-criteria optimization problems of mining engineering. After the comparison of advantages and deficiencies of both deterministic and fuzzy LP models, the conclusion presents benefits of the fuzzy LP model but is also stating that seeking the optimal plan of production means to accomplish the overall analysis that will encompass the LP model approaches.

Constitutive model of friction stir weld with consideration of its inhomogeneous mechanical properties

NASA Astrophysics Data System (ADS)

Zhang, Ling; Min, Junying; Wang, Bin; Lin, Jianping; Li, Fangfang; Liu, Jing

2016-03-01

In practical engineering, finite element(FE) modeling for weld seam is commonly simplified by neglecting its inhomogeneous mechanical properties. This will cause a significant loss in accuracy of FE forming analysis, in particular, for friction stir welded(FSW) blanks due to the large width and good formability of its weld seam. The inhomogeneous mechanical properties across weld seam need to be well characterized for an accurate FE analysis. Based on a similar AA5182 FSW blank, the metallographic observation and micro-Vickers hardness analysis upon the weld cross-section are performed to identify the interfaces of different sub-zones, i.e., heat affected zone(HAZ), thermal-mechanically affected zone(TMAZ) and weld nugget(WN). Based on the rule of mixture and hardness distribution, a constitutive model is established for each sub-zone to characterize the inhomogeneous mechanical properties across the weld seam. Uniaxial tensile tests of the AA5182 FSW blank are performed with the aid of digital image correlation(DIC) techniques. Experimental local stress-strain curves are obtained for different weld sub-zones. The experimental results show good agreement with those derived from the constitutive models, which demonstrates the feasibility and accuracy of these models. The proposed research gives an accurate characterization of inhomogeneous mechanical properties across the weld seam produced by FSW, which provides solutions for improving the FE simulation accuracy of FSW sheet forming.

Stress state of rocks with a system of workings

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nikiforovskii, V.S.; Seryakov, V.M.

1979-09-01

An investigation of the state of rocks in undisturbed form, and during disturbance by drivage of development workings and the working of seams or ore beds, is both important and also extremely complex in practice. The complete physical and mathematical formulation of the problem must take into account the complex geological structure (allowing for tectonics) of the region, the mutual influence of the systems of workings, the change in the mechanical characteristics in the vicinity of the workings, etc. All these factors make it necessary to solve spatial problems with inclusions and workings of arbitrary form. The literature gives datamore » on the stress in the rock in the vicinity of a working remote from the free surface and in its vicinity. However, the possibilities of an analytical investigation of the problem are limited to the simplest cases under conditions of plane deformation. Considerable success in the solution of problems of geomechanics has been attained using numerical methods, particularly the finite-element method, which enables us, without altering the algorithm, to change fairly rapidly and simply the outer and inner boundaries of the region and the properties of the medium, or to assign various boundary conditions. In this article we calculate the stress in the rocks around mining-out and development workings during mining of the Talnakh and Oktyabr' deposits by the longwall slicing system with stowing of the worked-out area.« less

Detecting and monitoring UCG subsidence with InSAR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mellors, R J; Foxall, W; Yang, X

2012-03-23

The use of interferometric synthetic aperture radar (InSAR) to measure surface subsidence caused by Underground Coal Gasification (UCG) is tested. InSAR is a remote sensing technique that uses Synthetic Aperture Radar images to make spatial images of surface deformation and may be deployed from satellite or an airplane. With current commercial satellite data, the technique works best in areas with little vegetation or farming activity. UCG subsidence is generally caused by roof collapse, which adversely affects UCG operations due to gas loss and is therefore important to monitor. Previous studies have demonstrated the usefulness of InSAR in measuring surface subsidencemore » related to coal mining and surface deformation caused by a coal mining roof collapse in Crandall Canyon, Utah is imaged as a proof-of-concept. InSAR data is collected and processed over three known UCG operations including two pilot plants (Majuba, South Africa and Wulanchabu, China) and an operational plant (Angren, Uzbekistan). A clear f eature showing approximately 7 cm of subsidence is observed in the UCG field in Angren. Subsidence is not observed in the other two areas, which produce from deeper coal seams and processed a smaller volume. The results show that in some cases, InSAR is a useful tool to image UCG related subsidence. Data from newer satellites and improved algorithms will improve effectiveness.« less

Mining Diagnostic Assessment Data for Concept Similarity

ERIC Educational Resources Information Center

Madhyastha, Tara; Hunt, Earl

2009-01-01

This paper introduces a method for mining multiple-choice assessment data for similarity of the concepts represented by the multiple choice responses. The resulting similarity matrix can be used to visualize the distance between concepts in a lower-dimensional space. This gives an instructor a visualization of the relative difficulty of concepts…

Multiple pass and multiple layer friction stir welding and material enhancement processes

DOEpatents

Feng, Zhili [Knoxville, TN; David, Stan A [Knoxville, TN; Frederick, David Alan [Harriman, TN

2010-07-27

Processes for friction stir welding, typically for comparatively thick plate materials using multiple passes and multiple layers of a friction stir welding tool. In some embodiments a first portion of a fabrication preform and a second portion of the fabrication preform are placed adjacent to each other to form a joint, and there may be a groove adjacent the joint. The joint is welded and then, where a groove exists, a filler may be disposed in the groove, and the seams between the filler and the first and second portions of the fabrication preform may be friction stir welded. In some embodiments two portions of a fabrication preform are abutted to form a joint, where the joint may, for example, be a lap joint, a bevel joint or a butt joint. In some embodiments a plurality of passes of a friction stir welding tool may be used, with some passes welding from one side of a fabrication preform and other passes welding from the other side of the fabrication preform.

49 CFR 178.60 - Specification 8AL steel cylinders with porous fillings for acetylene.

Code of Federal Regulations, 2012 CFR

2012-10-01

... process and a welded circumferential body seam is authorized. Longitudinal seams are not authorized. (b... using equipment and processes adequate to ensure that each cylinder produced conforms to the... operations. Liquid quenching is not authorized. (i) Openings. Standard taper pipe threads required in all...

49 CFR 178.60 - Specification 8AL steel cylinders with porous fillings for acetylene.

Code of Federal Regulations, 2014 CFR

2014-10-01

... process and a welded circumferential body seam is authorized. Longitudinal seams are not authorized. (b... using equipment and processes adequate to ensure that each cylinder produced conforms to the... operations. Liquid quenching is not authorized. (i) Openings. Standard taper pipe threads required in all...

49 CFR 178.60 - Specification 8AL steel cylinders with porous fillings for acetylene.

Code of Federal Regulations, 2013 CFR

2013-10-01

... process and a welded circumferential body seam is authorized. Longitudinal seams are not authorized. (b... using equipment and processes adequate to ensure that each cylinder produced conforms to the... operations. Liquid quenching is not authorized. (i) Openings. Standard taper pipe threads required in all...

16 CFR 1615.31 - Labeling, recordkeeping, advertising, retail display and guaranties.

Code of Federal Regulations, 2011 CFR

2011-01-01

... records required must establish a line of continuity through the process of manufacture of each production... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each..., seams, threads, stitches, and trims used in such prototype testing, relating such samples to the records...

16 CFR 1615.31 - Labeling, recordkeeping, advertising, retail display and guaranties.

Code of Federal Regulations, 2012 CFR

2012-01-01

... records required must establish a line of continuity through the process of manufacture of each production... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each..., seams, threads, stitches, and trims used in such prototype testing, relating such samples to the records...

16 CFR 1615.31 - Labeling, recordkeeping, advertising, retail display and guaranties.

Code of Federal Regulations, 2014 CFR

2014-01-01

... records required must establish a line of continuity through the process of manufacture of each production... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each..., seams, threads, stitches, and trims used in such prototype testing, relating such samples to the records...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2010 CFR

2010-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2011 CFR

2011-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2013 CFR

2013-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2012 CFR

2012-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

46 CFR 59.10-10 - Corroded surfaces.

Code of Federal Regulations, 2014 CFR

2014-10-01

... VESSELS AND APPURTENANCES Welding Repairs to Boilers and Pressure Vessels in -Service § 59.10-10 Corroded surfaces. (a) Corroded surfaces in the calking edges of circumferential seams may be built up by welding to... inches in length in a circumferential direction. (2) In all repairs to circumferential seams by welding...

30 CFR 57.22205 - Doors on main fans (I-A, II-A, III, and V-A mines).

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Doors on main fans (I-A, II-A, III, and V-A mines). 57.22205 Section 57.22205 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF... main fans (I-A, II-A, III, and V-A mines). In mines ventilated by multiple main fans, each main fan...

Degradation of a Multilayer Insulation Due to a Seam and a Penetration

NASA Technical Reports Server (NTRS)

Sumner, I. E.

1976-01-01

The degradation of the thermal performance of a multilayer insulation due to the presence of a seam and a penetration was studied. The multilayer insulation had 30 aluminized Mylar radiation shields with silk net spacers. The seam, an offset butt joint, caused a heat input of 0.169 watt per meter in addition to the basic insulation thermal performance of 0.388 watt per square meter obtained before the installation of the butt joint. The penetration, a fiberglass tank support strut, provided a heat input (including the degradation of the insulation) of 0.543 watt in addition to the basic insulation thermal performance of 0.452 watt per square meter obtained before the penetration.

16 CFR § 1615.31 - Labeling, recordkeeping, advertising, retail display and guaranties.

Code of Federal Regulations, 2013 CFR

2013-01-01

... records required must establish a line of continuity through the process of manufacture of each production... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each..., seams, threads, stitches, and trims used in such prototype testing, relating such samples to the records...

16 CFR 1616.31 - Labeling, recordkeeping, retail display and guaranties.

Code of Federal Regulations, 2014 CFR

2014-01-01

... process of manufacture of each production unit of articles of children's sleepwear, or fabrics or related... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each... sufficient to repeat the prototype tests required by § 1616.4 of the Standard for all fabrics, seams, threads...

16 CFR § 1616.31 - Labeling, recordkeeping, retail display and guaranties.

Code of Federal Regulations, 2013 CFR

2013-01-01

... process of manufacture of each production unit of articles of children's sleepwear, or fabrics or related... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each... sufficient to repeat the prototype tests required by § 1616.4 of the Standard for all fabrics, seams, threads...

16 CFR 1616.31 - Labeling, recordkeeping, retail display and guaranties.

Code of Federal Regulations, 2011 CFR

2011-01-01

... process of manufacture of each production unit of articles of children's sleepwear, or fabrics or related... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each... sufficient to repeat the prototype tests required by § 1616.4 of the Standard for all fabrics, seams, threads...

16 CFR 1616.31 - Labeling, recordkeeping, retail display and guaranties.

Code of Federal Regulations, 2012 CFR

2012-01-01

... process of manufacture of each production unit of articles of children's sleepwear, or fabrics or related... content, and details of construction on all seams, fabrics, threads, stitches, and trims used in each... sufficient to repeat the prototype tests required by § 1616.4 of the Standard for all fabrics, seams, threads...

46 CFR 160.151-15 - Design and performance of inflatable liferafts.

Code of Federal Regulations, 2010 CFR

2010-10-01

...-15 Section 160.151-15 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) EQUIPMENT... structural components. (b) Seams (Regulation III/30.2.1). Each seam must be at least as strong as the weakest... is greater. (k) Painter system (Regulation III/38.6.1). The painter protruding from the liferaft...

49 CFR 178.603 - Drop test.

Code of Federal Regulations, 2012 CFR

2012-10-01

... the fourth sample). Fifth drop: On a corner (using the fifth sample). Bags—single-ply with a side seam...). Bags—single-ply without a side seam, or multi-ply Three—(two drops per bag) First drop: Flat on a wide...) For a bag, neither the outermost ply nor an outer packaging exhibits any damage likely to adversely...

A Psychometric Study of the Infant and Toddler Intervals of the Social Emotional Assessment Measure

ERIC Educational Resources Information Center

Squires, Jane K.; Waddell, Misti L.; Clifford, Jantina R.; Funk, Kristin; Hoselton, Robert M.; Chen, Ching-I

2013-01-01

Psychometric and utility studies on Social Emotional Assessment Measure (SEAM), an innovative tool for assessing and monitoring social-emotional and behavioral development in infants and toddlers with disabilities, were conducted. The Infant and Toddler SEAM intervals were the study focus, using mixed methods, including item response theory…

Crenulation cleavage development by partitioning of deformation into zones of progressive shearing (combined shearing, shortening and volume loss) and progressive shortening (no volume loss): quantification of solution shortening and intermicrolithon-movement

NASA Astrophysics Data System (ADS)

Stewart, L. K.

1997-11-01

An analytical method for determining amounts of cleavage-normal dissolution and cleavage-parallel shear movement that occurred between adjacent microlithons during crenulation cleavage seam formation within a deformed slate is developed for the progressive bulk inhomogeneous shortening (PBIS) mechanism of crenulation cleavage formation. The method utilises structural information obtained from samples where a diverging bed and vein are offset by a crenulation cleavage seam. Several samples analysed using this method produced ratios of relative, cleavage-parallel movement of microlithons to the material thickness removed by dissolution typically in the range of 1.1-3.4:1. The mean amount of solution shortening attributed to the formation of the cleavage seams examined is 24%. The results indicate that a relationship may exist between the width of microlithons and the amount of cleavage-parallel intermicrolithon-movement. The method presented here has the potential to help determine whether crenulation cleavage seams formed by the progressive bulk inhomogeneous shortening mechanism or by that involving cleavage-normal pressure solution alone.

Structurally Altered Hard Coal in the Areas of Tectonic Disturbances - An Initial Attempt at Classification

NASA Astrophysics Data System (ADS)

Godyń, Katarzyna

2016-09-01

As regards the exploitation of hard coal seams, the near-fault zones and faults themselves are considered to be particularly dangerous areas, which is due to a high probability of the occurrence of gasogeodynamic phenomena. Tectonic dislocations running across a seam have a destructive impact on coal. Degradation of the coal structure, particularly visible in the microscale, is reflected in the coal's strength or gas properties. Such "structurally altered" coal is characterized by the presence of numerous fracturings, crushed areas, or dislocations of some of its fragments, and sometimes even the total destruction of the original structure. The present paper provides a detailed analysis and description of near-fault coal obtained from selected seams of the Upper Silesian Coal Basin, completed due to the application of optical methods. Both the type and the degree of changes in the structure of such coal were identified. On this basis, the author attempted to systematize the nomenclature used in relation to selected Upper Silesian hard coal seams, which, in turn, resulted in a proposed classification of the "altered structures" of the near-fault coal.

Stability Criteria of Fullerene-like Nanoparticles: Comparing V₂O5 to Layered Metal Dichalcogenides and Dihalides.

PubMed

Levi, Roi; Bar-Sadan, Maya; Albu-Yaron, Ana; Popovitz-Biro, Ronit; Houben, Lothar; Prior, Yehiam; Tenne, Reshef

2010-08-18

Numerous examples of closed-cage nanostructures, such as nested fullerene-like nanoparticles and nanotubes, formed by the folding of materials with layered structure are known. These compounds include WS₂, NiCl₂, CdCl₂, Cs₂O, and recently V₂O₅. Layered materials, whose chemical bonds are highly ionic in character, possess relatively stiff layers, which cannot be evenly folded. Thus, stress-relief generally results in faceted nanostructures seamed by edge-defects. V₂O₅, is a metal oxide compound with a layered structure. The study of the seams in nearly perfect inorganic "fullerene-like" hollow V₂O 5 nanoparticles (NIF-V₂O₅) synthesized by pulsed laser ablation (PLA), is discussed in the present work. The relation between the formation mechanism and the seams between facets is examined. The formation mechanism of the NIF-V₂O 5 is discussed in comparison to fullerene-like structures of other layered materials, like IF structures of MoS₂, CdCl₂, and Cs₂O. The criteria for the perfect seaming of such hollow closed structures are highlighted.

Laser welding process in PP moulding parts: Evaluation of seam performance

NASA Astrophysics Data System (ADS)

Oliveira, N.; Pontes, A. J.

2015-12-01

The Polypropylene is one of the most versatile polymer materials used in the industry. Due to this versatility, it is possible to use it in different products. This material can also be mixed with several additives namely glass fiber, carbon nanotubes, etc. This compatibility with different additives allows also obtaining products with characteristics that goes from an impact absorber to an electricity conductor. When is necessary to join components in PP they could be welded through hot plate, ultrasonic weld and also by laser. This study had the objective of study the influence of several variables, capable of influence the final quality of the seam. In this case were studied variables of the injection molding process as mold temperature and cooling time. Was also studied laser welding variables and different materials. The results showed that the variables that have the most influence were mould temperature, laser velocity and laser diameter. The seams were analyzed using Optical Microscopy technique. The seams showed perfect contact between the materials analyzed, despite the high standard variation presented in the mechanical testes.

Low distortion laser welding of cylindrical components

NASA Astrophysics Data System (ADS)

Kittel, Sonja

2011-02-01

Automotive components are for the most part cylindrical and thus the weld seams are of radial shape. Radial weld seams are usually produced by starting at a point on the component's surface rotating the component resulting in an overlap zone at the start/end of the weld. In this research, it is shown that the component's distortion strongly depends on the overlap of weld start and end. A correlation between overlap zone and distortion is verified by an experimental study. In order to reduce distortion generated by the overlap zone a special optics is used which allows shaping the laser beam into a ring shape which is then focused on the cylindrical surface and produces a radial ring weld seam simultaneously by one laser pulse. In doing this, the overlap zone is eliminated and distortion can be reduced. Radial weld seams are applied on precision samples and distortion is measured after welding. The distortion of the precision samples is measured by a tactile measuring method and a comparison of the results of welding with the ring optics to reference welds is done.

Energy-switching potential energy surface for ground-state C3

NASA Astrophysics Data System (ADS)

Rocha, C. M. R.; Varandas, A. J. C.

2018-05-01

The multiple energy switching scheme [J. Chem. Phys. 119 (2003) 2596] has been used to improve the double many-body expansion (DMBE II) potential energy surface of C3 near its linear global minima by morphing it with an accurate Taylor-series expansion [J. Chem. Phys. 144 (2016) 044307]. The final ES form attains the accuracy of the local form in reproducing the rovibrational spectrum of C3 while keeping unaltered all key attributes of the original DMBE II, namely conical intersection seams and dissociative channels. The ES form is therefore commended for adiabatic spectroscopic and reaction dynamics studies.

Geological occurrence response to trace elemental migration in coal liquefaction based on SPSS: take no. 11 coalbed in Antaibao mine for example

NASA Astrophysics Data System (ADS)

Xia, Xiaohong; Qin, Yong; Yang, Weifeng

2013-03-01

Coal liquefaction is an adoptable method to transfer the solid fossil energy into liquid oil in large scale, but the dirty material in which will migrate to different step of liquefaction. The migration rule of some trace elements is response to the react activity of macerals in coal and the geological occurrence of the element nature of itself. In this paper, from the SPSS data correlation analysis and hierarchical clustering dendrogram about the trace elements with macerals respond to coal liquefaction yield, it shows the trace elements in No.11 Antaibao coal seam originated from some of lithophile and sulphophle elements. Correlation coefficient between liquefaction yield of three organic macerals and migration of the elements in liquefaction residue indicated that the lithophile are easy to transfer to residue, while sulphophle are apt to in the liquid products. The activated macerals are response to sulphophle trace elements. The conclusion is useful to the coal blending and environmental effects on coal direct liquefaction.

Raman spectral characteristics of magmatic-contact metamorphic coals from Huainan Coalfield, China

NASA Astrophysics Data System (ADS)

Chen, Shancheng; Wu, Dun; Liu, Guijian; Sun, Ruoyu

2017-01-01

Normal burial metamorphism of coal superimposed by magmatic-contact metamorphism makes the characteristics of the Raman spectrum of coal changed. Nine coal samples were chosen at a coal transect perpendicular to the intrusive dike, at the No. 3 coal seam, Zhuji Coal Mine, Huainan Coalfield, China, with different distances from dike-coal boundary (DCB). Geochemical (proximate and ultimate) analysis and mean random vitrinite reflectance (R0, %) indicate that there is a significant relationship between the values of volatile matter and R0 in metamorphosed coals. Raman spectra show that the graphite band (G band) becomes the major band but the disordered band (D band) disappears progressively, with the increase of metamorphic temperature in coals, showing that the structural organization in high-rank contact-metamorphosed coals is close to that of well-crystallized graphite. Evident relationships are observed between the calculated Raman spectral parameters and the peak metamorphic temperature, suggesting some spectral parameters have the potentials to be used as geothermometers for contact-metamorphic coals.

Dust control at longwalls with water infusion and foam. Technical progress report through November 30, 1982

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1982-01-01

Foam spray equipment and materials for dust suppression on longwall double drum shearer faces have been procured. This equipment includes metering pumps, foam generators and mounting brackets, foam solutions, flow meters, real time and gravimetric sampling equipment, hoses and valve banks. Initial tests have been conducted in the laboratory with three types of generators and five types of foam solutions. Based on these tests, Senior Conflow's cluster spray and Onyx Chemical Company's millifoam solution have been selected. For pumping foam solution to the shearer, Jon Bean's 2 hp, 120 VAC single-phase ceramic lined piston pump has been selected. For fieldmore » tests, equipment has been installed underground in Dobbin mine in Upper Freeport seam on Eickhoff EDW 300 double drum shearer. Foamspray tests have been conducted. Real time and gravimetric dust samples have been collected. Real time sampling results indicate a dust level reduction of up to 37 percent with foam spray compared to the base case of water sprays.« less

WEST AND EAST PALISADES ROADLESS AREAS, IDAHO AND WYOMING.

USGS Publications Warehouse

Oriel, Steven S.; Benham, John R.

1984-01-01

Studies of the West and East Palisades Roadless Areas, which lie within the Idaho-Wyoming thrust belt, document structures, reservoir formations, source beds, and thermal maturities comparable to those in producing oil and gas field farther south in the belt. Therefore, the areas are highly favorable for the occurrence of oil and gas. Phosphate beds of appropriate grade within the roadless areas are thinner and less accessible than those being mined from higher thrust sheets to the southwest; however, they contain 98 million tons of inferred phosphate rock resources in areas of substantiated phosphate resource potential. Sparsely distributed thin coal seams occur in the roadless areas. Although moderately pure limestone is present, it is available from other sources closer to markets. Geochemical anomalies from stream-sediment and rock samples for silver, copper, molydenum, and lead occur in the roadless areas but they offer little promise for the occurrence of metallic mineral resources. A possible geothermal resource is unproven, despite thermal phenomena at nearby sites.

An overview of the Permian (Karoo) coal deposits of southern Africa

NASA Astrophysics Data System (ADS)

Cairncross, B.

2001-08-01

The coal deposits of southern Africa (Botswana, Malawi, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Zambia and Zimbabwe) are reviewed. The coal seams formed during two periods, the Early Permian (Artinskian-Kungurian) and the Late Permian (Ufimian-Kazanian). The coals are associated with non-marine terrestrial clastic sedimentary sequences, most commonly mudrock and sandstones, assigned to the Karoo Supergroup. The Early Permian coals are most commonly sandstone-hosted while the younger coals typically occur interbedded with mudstones. The sediments were deposited in varying tectono-sedimentary basins such as foreland, intracratonic rifts and intercratonic grabens and half-grabens. The depositional environments that produced the coal-bearing successions were primarily deltaic and fluvial, with some minor shoreline and lacustrine settings. Coals vary in rank from high-volatile bituminous to anthracite and characteristically have a relatively high inertinite component, and medium- to high-ash content. In countries where coal is mined, it is used for power generation, coking coal, synfuel generation, gasification and for (local) domestic household consumption.

Analysis of rail welding methods for mine rail access with the use of modern technologies

NASA Astrophysics Data System (ADS)

Usoltsev, A. A.; Shevchenko, R. A.; Kozyrev, N. A.; Kriukov, R. E.; Shishkin, P. E.

2017-09-01

Welded joint zones are weak sections of the railway track for all traffic cases (in the case of high-speed traffic and heavy traffic). In the paper advantages and disadvantages of the basic ways of rails welding, which are widely used today, are considered: electrocontact and aluminothermic. Carefully selected mode of differentially thermally strengthened rails string will allow the process of correction after heat treatment to be minimized and internal residual compressive stresses to be kept. Particular attention should be paid to the method of rails welding, in which after rails welding during their cooling it is offered to perform quasi-isothermal exposure in the temperature range of fine structure formation by passing pulses of alternating electric current through the welded joint maintaining this temperature until the end of the transformation. The use of quasi-isothermal exposure at a temperature of 600 - 650 °C makes it possible to obtain a finely dispersed structure of the welded seam of rails without additional heat treatment.

Environmental implications of coal development: an interdisciplinary research team approach

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barker, W.T.; Brun, L.; Enz, J.

In May, 1974 a team of researchers from North Dakota State University launched a project aimed at investigating The Implications of Coal Development on the Atmospheric Environment and Plant Ecosystems of Selected Sites in Western North Dakota. It was an interdisciplinary effort of four basic study areas, namely: Soils, Climatology, Engineering, and Botany. Support was provided by the US Forest Service, USDA, under a Surface Environment and Mining (SEAM) cooperative agreement with the North Dakota Agricultural Experiment Station. The investigations, which lasted 4-1/2 years, were designed to accomplish three primary objectives. First was to analyze the frequency, intensity, and durationmore » of low-level radiation inversions in western North Dakota. The second was to determine the probable dispersion of wastes to the atmosphere from various theoretical operational levels and types of coal development in the specified area. Lastly was evaluation of the effects of probable changes in air quality on the plant ecosystems in the area.« less

In situ capture gamma-ray analysis of coal in an oversize borehole

USGS Publications Warehouse

Mikesell, J.L.; Dotson, D.W.; Senftle, F.E.; Zych, R.S.; Koger, J.; Goldman, L.

1983-01-01

In situ capture gamma-ray analysis in a coal seam using a high resolution gamma-ray spectrometer in a close-fitting borehole has been reported previously. In order to check the accuracy of the method under adverse conditions, similar measurements were made by means of a small-diameter sonde in an oversize borehole in the Pittsburgh seam, Greene County, Pennsylvania. The hole was 5 times the diameter of the sonde, a ratio that substantially increased the contribution of water (hydrogen) to the total spectral count and reduced the size of the sample measured by the detector. The total natural count, the 40K,count, and the intensities of capture gamma rays from Si, Ca, H, and Al were determined as a function of depth above, through, and below the coal seam. From these logs, the depth and width of the coal seam and its partings were determined. Spectra were accumulated in the seam for 1 h periods by using neutron sources of different strengths. From the spectra obtained by means of several 252Cf neutron sources of different sizes, the ultimate elemental analysis and ash content were determined. The results were not as good as those obtained previously in a close-fitting borehole. However, the results did improve with successively larger source-to-detector distances, i.e.,as the count contribution due to hydrogen in the water decreased. It was concluded that in situ borehole analyses should be made in relatively close-fitting boreholes. ?? 1983.

The C. elegans embryonic fate specification factor EGL-18 (GATA) is reutilized downstream of Wnt signaling to maintain a population of larval progenitor cells.

PubMed

Gorrepati, Lakshmi; Eisenmann, David M

2015-01-01

In metazoans, stem cells in developing and adult tissues can divide asymmetrically to give rise to a daughter that differentiates and a daughter that retains the progenitor fate. Although the short-lived nematode C. elegans does not possess adult somatic stem cells, the lateral hypodermal seam cells behave in a similar manner: they divide once per larval stage to generate an anterior daughter that adopts a non-dividing differentiated fate and a posterior daughter that retains the seam fate and the ability to divide further. Wnt signaling pathway is known to regulate the asymmetry of these divisions and maintain the progenitor cell fate in one daughter, but how activation of the Wnt pathway accomplished this was unknown. We describe here our recent work that identified the GATA transcription factor EGL-18 as a downstream target of Wnt signaling necessary for maintenance of a progenitor population of larval seam cells. EGL-18 was previously shown to act in the initial specification of the seam cells in the embryo. Thus the acquisition of a Wnt-responsive cis-regulatory module allows an embryonic fate specification factor to be reutilized later in life downstream of a different regulator (Wnt signaling) to maintain a progenitor cell population. These results support the use of seam cell development in C. elegans as a simple model system for studying stem and progenitor cell biology.

Probabilistic modelling and uncertainty analysis of flux and water balance changes in a regional aquifer system due to coal seam gas development.

PubMed

Sreekanth, J; Cui, Tao; Pickett, Trevor; Rassam, David; Gilfedder, Mat; Barrett, Damian

2018-09-01

Large scale development of coal seam gas (CSG) is occurring in many sedimentary basins around the world including Australia, where commercial production of CSG has started in the Surat and Bowen basins. CSG development often involves extraction of large volumes of water that results in depressurising aquifers that overlie and/or underlie the coal seams thus perturbing their flow regimes. This can potentially impact regional aquifer systems that are used for many purposes such as irrigation, and stock and domestic water. In this study, we adopt a probabilistic approach to quantify the depressurisation of the Gunnedah coal seams and how this impacts fluxes to, and from the overlying Great Artesian Basin (GAB) Pilliga Sandstone aquifer. The proposed method is suitable when effects of a new resource development activity on the regional groundwater balance needs to be assessed and account for large scale uncertainties in the groundwater flow system and proposed activity. The results indicated that the extraction of water and gas from the coal seam could potentially induce additional fluxes from the Pilliga Sandstone to the deeper formations due to lowering pressure heads in the coal seams. The median value of the rise in the maximum flux from the Pilliga Sandstone to the deeper formations is estimated to be 85ML/year, which is considered insignificant as it forms only about 0.29% of the Long Term Annual Average Extraction Limit of 30GL/year from the groundwater management area. The probabilistic simulation of the water balance components indicates only small changes being induced by CSG development that influence interactions of the Pilliga Sandstone with the overlying and underlying formations and with the surface water courses. The current analyses that quantified the potential maximum impacts of resource developments and how they influences the regional water balance, would greatly underpin future management decisions. Copyright © 2018 Elsevier B.V. All rights reserved.

Optimization of enhanced coal-bed methane recovery using numerical simulation

NASA Astrophysics Data System (ADS)

Perera, M. S. A.; Ranjith, P. G.; Ranathunga, A. S.; Koay, A. Y. J.; Zhao, J.; Choi, S. K.

2015-02-01

Although the enhanced coal-bed methane (ECBM) recovery process is one of the potential coal bed methane production enhancement techniques, the effectiveness of the process is greatly dependent on the seam and the injecting gas properties. This study has therefore aimed to obtain a comprehensive knowledge of all possible major ECBM process-enhancing techniques by developing a novel 3D numerical model by considering a typical coal seam using the COMET 3 reservoir simulator. Interestingly, according to the results of the model, the generally accepted concept that there is greater CBM (coal-bed methane) production enhancement from CO2 injection, compared to the traditional water removal technique, is true only for high CO2 injection pressures. Generally, the ECBM process can be accelerated by using increased CO2 injection pressures and reduced temperatures, which are mainly related to the coal seam pore space expansion and reduced CO2 adsorption capacity, respectively. The model shows the negative influences of increased coal seam depth and moisture content on ECBM process optimization due to the reduced pore space under these conditions. However, the injection pressure plays a dominant role in the process optimization. Although the addition of a small amount of N2 into the injecting CO2 can greatly enhance the methane production process, the safe N2 percentage in the injection gas should be carefully predetermined as it causes early breakthroughs in CO2 and N2 in the methane production well. An increased number of production wells may not have a significant influence on long-term CH4 production (50 years for the selected coal seam), although it significantly enhances short-term CH4 production (10 years for the selected coal seam). Interestingly, increasing the number of injection and production wells may have a negative influence on CBM production due to the coincidence of pressure contours created by each well and the mixing of injected CO2 with CH4.

Stochastic production phase design for an open pit mining complex with multiple processing streams

NASA Astrophysics Data System (ADS)

Asad, Mohammad Waqar Ali; Dimitrakopoulos, Roussos; van Eldert, Jeroen

2014-08-01

In a mining complex, the mine is a source of supply of valuable material (ore) to a number of processes that convert the raw ore to a saleable product or a metal concentrate for production of the refined metal. In this context, expected variation in metal content throughout the extent of the orebody defines the inherent uncertainty in the supply of ore, which impacts the subsequent ore and metal production targets. Traditional optimization methods for designing production phases and ultimate pit limit of an open pit mine not only ignore the uncertainty in metal content, but, in addition, commonly assume that the mine delivers ore to a single processing facility. A stochastic network flow approach is proposed that jointly integrates uncertainty in supply of ore and multiple ore destinations into the development of production phase design and ultimate pit limit. An application at a copper mine demonstrates the intricacies of the new approach. The case study shows a 14% higher discounted cash flow when compared to the traditional approach.

Coal-bed methane water effects on dill and essential oils

USDA-ARS?s Scientific Manuscript database

Pumping water from coal seams decreases the pressure in the seam and in turn releases trapped methane; this is the most common and economic way of methane extraction. The water that is pumped out is known as coal-bed methane water (CBMW), which is high in sodium and other salts. In past 25 years, th...

49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

Code of Federal Regulations, 2014 CFR

2014-10-01

.... Cylinders closed in by spinning process are not authorized. (b) Authorized steel. Steel used in the.... Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced... seams must be of the butt welded type. Welds must be made by a machine process including automatic feed...

49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

Code of Federal Regulations, 2013 CFR

2013-10-01

.... Cylinders closed in by spinning process are not authorized. (b) Authorized steel. Steel used in the.... Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced... seams must be of the butt welded type. Welds must be made by a machine process including automatic feed...

49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

Code of Federal Regulations, 2012 CFR

2012-10-01

.... Cylinders closed in by spinning process are not authorized. (b) Authorized steel. Steel used in the.... Cylinders must be manufactured using equipment and processes adequate to ensure that each cylinder produced... seams must be of the butt welded type. Welds must be made by a machine process including automatic feed...

Validation of the Social Exercise and Anxiety Measure (SEAM): Assessing fears, avoidance, and importance of social exercise

PubMed Central

Levinson, Cheri A.; Rodebaugh, Thomas L.; Menatti, Andrew R.; Weeks, Justin W.

2012-01-01

In two studies (N = 416; N = 118) examining responses from undergraduates, we developed the Social Exercise and Anxiety Measure (SEAM) and tested its factorial, convergent, and divergent validity. Our results demonstrate that the SEAM exhibits an excellent three factor structure consisting of the following subscales: Social Exercise Self-efficacy, Gym Avoidance, and Exercise Importance. In both studies, Social Exercise Self-efficacy correlated negatively and Gym Avoidance correlated positively with social interaction anxiety, fear of scrutiny, and fear of negative evaluation. Exercise Importance correlated positively with frequency of exercise and frequency of public exercise. Implications for the mental and physical health of individuals with high levels of social anxiety are discussed. PMID:24244069

Parallax-Robust Surveillance Video Stitching

PubMed Central

He, Botao; Yu, Shaohua

2015-01-01

This paper presents a parallax-robust video stitching technique for timely synchronized surveillance video. An efficient two-stage video stitching procedure is proposed in this paper to build wide Field-of-View (FOV) videos for surveillance applications. In the stitching model calculation stage, we develop a layered warping algorithm to align the background scenes, which is location-dependent and turned out to be more robust to parallax than the traditional global projective warping methods. On the selective seam updating stage, we propose a change-detection based optimal seam selection approach to avert ghosting and artifacts caused by moving foregrounds. Experimental results demonstrate that our procedure can efficiently stitch multi-view videos into a wide FOV video output without ghosting and noticeable seams. PMID:26712756

Use of natural and applied tracers to guide targeted remediation efforts in an acid mine drainage system, Colorado Rockies, USA

USGS Publications Warehouse

Cowie, Rory; Williams, Mark W.; Wireman, Mike; Runkel, Robert L.

2014-01-01

Stream water quality in areas of the western United States continues to be degraded by acid mine drainage (AMD), a legacy of hard-rock mining. The Rico-Argentine Mine in southwestern Colorado consists of complex multiple-level mine workings connected to a drainage tunnel discharging AMD to passive treatment ponds that discharge to the Dolores River. The mine workings are excavated into the hillslope on either side of a tributary stream with workings passing directly under the stream channel. There is a need to define hydrologic connections between surface water, groundwater, and mine workings to understand the source of both water and contaminants in the drainage tunnel discharge. Source identification will allow targeted remediation strategies to be developed. To identify hydrologic connections we employed a combination of natural and applied tracers including isotopes, ionic tracers, and fluorescent dyes. Stable water isotopes (δ18O/δD) show a well-mixed hydrological system, while tritium levels in mine waters indicate a fast flow-through system with mean residence times of years not decades or longer. Addition of multiple independent tracers indicated that water is traveling through mine workings with minimal obstructions. The results from a simultaneous salt and dye tracer application demonstrated that both tracer types can be successfully used in acidic mine water conditions.

Progress in the Visualization and Mining of Chemical and Target Spaces.

PubMed

Medina-Franco, José L; Aguayo-Ortiz, Rodrigo

2013-12-01

Chemogenomics is a growing field that aims to integrate the chemical and target spaces. As part of a multi-disciplinary effort to achieve this goal, computational methods initially developed to visualize the chemical space of compound collections and mine single-target structure-activity relationships, are being adapted to visualize and mine complex relationships in chemogenomics data sets. Similarly, the growing evidence that clinical effects are many times due to the interaction of single or multiple drugs with multiple targets, is encouraging the development of novel methodologies that are integrated in multi-target drug discovery endeavors. Herein we review advances in the development and application of approaches to generate visual representations of chemical space with particular emphasis on methods that aim to explore and uncover relationships between chemical and target spaces. Also, progress in the data mining of the structure-activity relationships of sets of compounds screened across multiple targets are discussed in light of the concept of activity landscape modeling. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Integrated stratigraphy of Paleocene lignite seams of the fluvial Tullock Formation, Montana (USA).

NASA Astrophysics Data System (ADS)

Noorbergen, Lars J.; Kuiper, Klaudia F.; Hilgen, Frederik J.; Krijgsman, Wout; Dekkers, Mark J.; Smit, Jan; Abels, Hemmo A.

2015-04-01

Coal-bearing fluvial sedimentation is generally thought to be dominated by autogenic processes that are processes intrinsic to the sedimentary system. Ongoing research however suggests that several fluvial processes such as floodplain inundation and avulsion, can also be controlled by external forcing such as orbital climate change. Still, the exact role of orbital climate forcing in fluvial sediments is difficult to decipher since riverine deposits are complicated by variable sedimentation rates including erosion of previously deposited material, by lateral heterogeneity of sedimentation, and by scarcity of independent dating methods. The early Paleocene lignite-bearing Tullock Formation of the Williston Basin in eastern Montana represents a record of fluvial sedimentation that is perfectly exposed and, displays a seemingly regular alternation of sandstones and lignite seams. These coal beds contain multiple volcanic ash layers. Here, we use an integrated stratigraphic approach (litho- and magnetostratigraphy, geochemical fingerprinting and radio-isotope dating of volcanic ash layers) to establish a high-resolution time frame for the early Paleocene fluvial sediments. First age estimations indicate that the Tullock Formation in Eastern Montana was deposited over a time span of ~ 1000 kyr subsequent to the Cretaceous - Paleogene boundary, dated at ~ 65.95 Ma [1]. Initial high-resolution magnetostratigraphy revealed the occurrence of the C29r/C29n polarity reversal which was stratigraphic consistent at different field locations. We investigate the regional significance of sedimentary change at multiple sites of the same age in order to provide improved insight on the role of orbital forcing in fluvial coal formation. References: [1] Kuiper, K.F., Deino, A., Hilgen, F.J., Krijgsman, W., Renne, P.R., Wijbrans, J.R. (2008). Synchronizing Rock Clocks of Earth History. Science 320, 500-504.

Spectroscopic analysis technique for arc-welding process control

NASA Astrophysics Data System (ADS)

Mirapeix, Jesús; Cobo, Adolfo; Conde, Olga; Quintela, María Ángeles; López-Higuera, José-Miguel

2005-09-01

The spectroscopic analysis of the light emitted by thermal plasmas has found many applications, from chemical analysis to monitoring and control of industrial processes. Particularly, it has been demonstrated that the analysis of the thermal plasma generated during arc or laser welding can supply information about the process and, thus, about the quality of the weld. In some critical applications (e.g. the aerospace sector), an early, real-time detection of defects in the weld seam (oxidation, porosity, lack of penetration, ...) is highly desirable as it can reduce expensive non-destructive testing (NDT). Among others techniques, full spectroscopic analysis of the plasma emission is known to offer rich information about the process itself, but it is also very demanding in terms of real-time implementations. In this paper, we proposed a technique for the analysis of the plasma emission spectrum that is able to detect, in real-time, changes in the process parameters that could lead to the formation of defects in the weld seam. It is based on the estimation of the electronic temperature of the plasma through the analysis of the emission peaks from multiple atomic species. Unlike traditional techniques, which usually involve peak fitting to Voigt functions using the Levenberg-Marquardt recursive method, we employ the LPO (Linear Phase Operator) sub-pixel algorithm to accurately estimate the central wavelength of the peaks (allowing an automatic identification of each atomic species) and cubic-spline interpolation of the noisy data to obtain the intensity and width of the peaks. Experimental tests on TIG-welding using fiber-optic capture of light and a low-cost CCD-based spectrometer, show that some typical defects can be easily detected and identified with this technique, whose typical processing time for multiple peak analysis is less than 20msec. running in a conventional PC.

16 CFR 1615.4 - Test procedure.

Code of Federal Regulations, 2010 CFR

2010-01-01

... three Samples meet all the test criteria of § 1615.3(b), accept the seam design. If one or more of the... additional Samples meet all the test criteria of § 1615.3(b) accept the seam design. If one or more of the... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Test procedure. 1615.4 Section 1615.4...

16 CFR 1616.4 - Sampling and acceptance procedures.

Code of Federal Regulations, 2011 CFR

2011-01-01

... specimen to one of the three samples. Test each set of three samples and accept or reject each seam design... all the test criteria of § 1616.3(b), accept the seam design. If one or more of the three additional.... Test the sets of three samples and accept or reject the type of trim and design on the same basis as...

16 CFR 1616.4 - Sampling and acceptance procedures.

Code of Federal Regulations, 2012 CFR

2012-01-01

... specimen to one of the three samples. Test each set of three samples and accept or reject each seam design... all the test criteria of § 1616.3(b), accept the seam design. If one or more of the three additional.... Test the sets of three samples and accept or reject the type of trim and design on the same basis as...

16 CFR 1616.4 - Sampling and acceptance procedures.

Code of Federal Regulations, 2010 CFR

2010-01-01

... specimen to one of the three samples. Test each set of three samples and accept or reject each seam design... all the test criteria of § 1616.3(b), accept the seam design. If one or more of the three additional.... Test the sets of three samples and accept or reject the type of trim and design on the same basis as...

Thermo-Mechanical Processing in Friction Stir Welds

NASA Technical Reports Server (NTRS)

Schneider, J. A.; Nunes, A. C., Jr.

2002-01-01

In Friction Stir Welding (FSW) a rotating pin-tool inserted into a weld seam literally stirs the edges of the seam together. In this study, two flow paths are proposed that define the FWS zone. Studies using a longitudinal tungsten wire (0.0025 dia.) were used to visualize and document the material flow. The material flow path is described using a mathematical model.

Stability Criteria of Fullerene-like Nanoparticles: Comparing V2O5 to Layered Metal Dichalcogenides and Dihalides

PubMed Central

Levi, Roi; Bar-Sadan, Maya; Albu-Yaron, Ana; Popovitz-Biro, Ronit; Houben, Lothar; Prior, Yehiam; Tenne, Reshef

2010-01-01

Numerous examples of closed-cage nanostructures, such as nested fullerene-like nanoparticles and nanotubes, formed by the folding of materials with layered structure are known. These compounds include WS2, NiCl2, CdCl2, Cs2O, and recently V2O5. Layered materials, whose chemical bonds are highly ionic in character, possess relatively stiff layers, which cannot be evenly folded. Thus, stress-relief generally results in faceted nanostructures seamed by edge-defects. V2O5, is a metal oxide compound with a layered structure. The study of the seams in nearly perfect inorganic "fullerene-like" hollow V2O5 nanoparticles (NIF-V2O5) synthesized by pulsed laser ablation (PLA), is discussed in the present work. The relation between the formation mechanism and the seams between facets is examined. The formation mechanism of the NIF-V2O5 is discussed in comparison to fullerene-like structures of other layered materials, like IF structures of MoS2, CdCl2, and Cs2O. The criteria for the perfect seaming of such hollow closed structures are highlighted. PMID:28883335

Mechanisms of palatal epithelial seam disintegration by Transforming Growth Factor (TGF)-β3

PubMed Central

Ahmed, Shaheen; Liu, Chang-Chih; Nawshad, Ali

2007-01-01

TGFβ3 signaling initiates and completes sequential phases of cellular differentiation that is required for complete disintegration of the palatal medial edge seam, that progresses between 14 to 17 embryonic days in the murine system, which is necessary in establishing confluence of the palatal stroma. Understanding the cellular mechanism of palatal MES disintegration in response to TGFβ3 signaling will result in new approaches to defining the causes of cleft palate and other facial clefts that may result from failure of seam disintegration. We have isolated MES primary cells to study the details of MES disintegration mechanism by TGFβ3 during palate development using several biochemical and genetic approaches. Our results demonstrate a novel mechanism of MES disintegration where MES, independently yet sequentially, undergoes cell cycle arrest, cell migration and apoptosis to generate immaculate palatal confluency during palatogenesis in response to robust TGFβ3 signaling. The results contribute to a missing fundamental element to our base knowledge of the diverse roles of TGFβ3 in functional and morphological changes that MES undergo during palatal seam disintegration. We believe that our findings will lead to more effective treatment of facial clefting. PMID:17698055

Resistivity profiling to locate an infiltration area and the possible recovery of the dried Andara lake (Picos de Europa National Park, Spain)

NASA Astrophysics Data System (ADS)

Gallastegui, Jorge; Olona, Javier; Farias, Pedro; González-Cortina, Juan Manuel; Fernández-Viejo, Gabriela; López, Carlos; Cadenas, Patricia

2013-04-01

The Ándara Lake constituted the third mass of water by extension (approximately 19000 m2) within the calcareous Picos de Europa Massif in NW Spain, but only a small pond remains today (about 1250 m2). The lake developed in a former glacial valley and its sudden draining occurred in the second decade of the 20th century, during the development of underground Pb-Zn mining, between 1889 and 1929, in the vicinity. Old mining maps show that there were shallow galleries active below the bottom of the ancient lake. The present study was requested by the Picos de Europa National Park Administration (Spanish Ministry of Environment) with the purpose of: i) localizing the areas of water infiltration and ii) establishing the cause of the draining, specially its possible relation with the mining activity in the surroundings. With this aim a geological study of the substrate of the lake was made, followed by a series of electrical resistivity profiles. Three resistivity parallel profiles were recorded along the axis of the dried lake on the 29th July. Each profile included 56 electrodes with 5 m spacing for a total profile length of 275 m. Data was recorded in both dipole-dipole and Schlumberger array configuration. The western profile had been recorded earlier in the summer (30th June) and was also repeated towards the end of the season (3rd September) in order to evaluate the evolution of the infiltrations. The results showed two areas of infiltration to the NE and SW of the present-day pond. Both of them cut across the underlying carboniferous limestone. However. the southwestern anomaly does not reach the surface and may be related with water flowing in karstic conduits in the limestone. The northeastern one reached the surface and the anomaly decreased as the pond dried during the summer allowing us to interpret it as the main area of infiltration. This area coincides with the intersection of two seams exploited both on the surface and by underground mining. This corroborates the relationship between the water disappearance and the mining activities, which is an indispensable condition for the National Park management to consider taking any future actions aimed to a possible recovery of the original water mass.

Practical small-scale explosive seam welding

NASA Technical Reports Server (NTRS)

Bement, L. J.

1983-01-01

A small-scale explosive seam welding process has been developed that can significantly contribute to remote metal joining operations under hazardous or inaccessible conditions, such as nuclear reactor repair and assembly of structure in space. This paper describes this explosive seam welding process in terms of joining principles, variables, types of joints created, capabilities, and applications. Very small quantities of explosive in a ribbon configuration are used to create narrow (less than 0.5 inch), long-length, uniform, hermetically sealed joints that exhibit parent metal properties in a wide variety of metals, alloys, and combinations. The practicality of this process has been demonstrated by its current acceptance, as well as its capabilities that are superior in many applications to the universally accepted joining processes, such as mechanical fasteners, fusion and resistance welding, and adhesives.

Evaluation of a monorail mine haulage system

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oguz, S.; Stefanko, R.

1971-02-01

The following advantages accrue to a monorail system compared to track haulage: Derailment is impossible; track and road maintenance is eliminated; higher gradient can be overcome with less power demand; equipment maintenance is reduced drastically; haulage cost per ton-mile is reduced because less power is consumed; it is not affected by a weak floor and back conditions; initial capital cost is much less than track haulage; and it is easily adopted to material and mantrip use. The basic conclusion to be derived from this study is that the monorail system is versatile. Besides its use in material handling and formore » mantrips in Europe and Great Britain, it can be used for ore haulage in small mines. The monorail requires a lower initial capital investment in addition to reduced operational and maintenance costs. Floor maintenance of haulage ways is completely eliminated. Haulage capacity of the system can be increased by eliminating waiting times, speeding up the monorail and adding more containers to the system. These facts establish the superiority of the monorail system over conventional equipment and should strongly be considered. For material handling very little clearance is required above the floor to move material either by hand or by rope hoist or even pushing it with a tractor. Therefore, a low seam is not a handicap to a monorail system in material handling. However, some modifications on the system may be necessary for different applications.« less

Controls on boron and germanium distribution in the low-sulfur Amos coal bed, Western Kentucky coalfield, USA

USGS Publications Warehouse

Hower, J.C.; Ruppert, L.F.; Williams, D.A.

2002-01-01

The Duckmantian-aged Amos coal bed is a thin (<51 cm) coal bed that occurs in lobate southwest-trending pods separated by thin sandstones in the Western Kentucky coalfield. The coal bed, which is comprised of up to two benches and a rider coal, is low in ash yield (<6%) and sulfur content (<1%). The coal tends to be thin (<40 cm), but it was heavily mined in the 1980s because it could be combusted as mined. Geochemical analysis of the Amos coal bed shows higher concentrations of B and Ge than other Western Kentucky coal beds. High total B concentrations as well as high B/Be, both considered to be indicators of marine environments, increase toward the top of the coal bed. Most of the B values for the Amos samples range from 66 to 103 ppm (whole coal basis) indicating deposition in a brackish environment. High Ge concentrations in coals have been considered to be a function of seam thickness and proximity to the top and bottom of the coal bed. Thin coals, such as the Amos, are dominated by the coal bed margins and, therefore, have a tendency to have relatively high Ge concentrations. In the case of the Amos coal bed, the lower bench has a higher Ge content, suggesting that the substrate was a more important source of Ge than the roof rock. ?? 2002 Elsevier Science B.V. All rights reserved.

Technique for predicting ground-water discharge to surface coal mines and resulting changes in head

USGS Publications Warehouse

Weiss, L.S.; Galloway, D.L.; Ishii, Audrey L.

1986-01-01

Changes in seepage flux and head (groundwater level) from groundwater drainage into a surface coal mine can be predicted by a technique that considers drainage from the unsaturated zone. The user applies site-specific data to precalculated head and seepage-flux profiles. Groundwater flow through hypothetical aquifer cross sections was simulated using the U.S. Geological Survey finite-difference model, VS2D, which considers variably saturated two-dimensional flow. Conceptual models considered were (1) drainage to a first cut, and (2) drainage to multiple cuts, which includes drainage effects of an area surface mine. Dimensionless head and seepage flux profiles from 246 simulations are presented. Step-by-step instructions and examples are presented. Users are required to know aquifer characteristics and to estimate size and timing of the mine operation at a proposed site. Calculated groundwater drainage to the mine is from one excavated face only. First cut considers confined and unconfined aquifers of a wide range of permeabilities; multiple cuts considers unconfined aquifers of higher permeabilities only. The technique, developed for Illinois coal-mining regions that use area surface mining and evaluated with an actual field example, will be useful in assessing potential hydrologic impacts of mining. Application is limited to hydrogeologic settings and mine operations similar to those considered. Fracture flow, recharge, and leakage are nor considered. (USGS)

Feasibility of CO2 Sequestration as a Closure Option for Underground Coal Mine

NASA Astrophysics Data System (ADS)

Ray, Sutapa; Dey, Kaushik

2018-04-01

The Kyoto Protocol, 1998, was signed by member countries to reduce greenhouse gas (GHG) emissions to a minimum acceptable level. India agreed to Kyoto Protocol since 2002 and started its research on GHG mitigation. Few researchers have carried out research work on CO2 sequestration in different rock formations. However, CO2 sequestration in abandoned mines has yet not drawn its attention largely. In the past few years or decades, a significant amount of research and development has been done on Carbon Capture and Storage (CCS) technologies, since it is a possible solution for assuring less emission of CO2 to the atmosphere from power plants and some other major industrial plants. CCS mainly involves three steps: (a) capture and compression of CO2 from source (power plants and industrial areas), (b) transportation of captured CO2 to the storage mine and (c) injecting CO2 into underground mine. CO2 is stored at an underground mine mainly in three forms: (1) adsorbed in the coals left as pillars of the mine, (2) absorbed in water through a chemical process and (3) filled in void with compressed CO2. Adsorption isotherm is a graph developed between the amounts of adsorbate adsorbed on the surface of adsorbent and the pressure at constant temperature. Various types of adsorption isotherms are available, namely, Freundlich, Langmuir and BET theory. Indian coal is different in origin from most of the international coal deposits and thus demands isotherm experiments of the same to arrive at the right adsorption isotherm. To carry out these experiments, adsorption isotherm set up is fabricated in the laboratory with a capacity to measure the adsorbed volume up to a pressure level of 100 bar. The coal samples are collected from the pillars and walls of the underground coal seam using a portable drill machine. The adsorption isotherm experiments have been carried out for the samples taken from a mine. From the adsorption isotherm experiments, Langmuir Equation is found to be more acceptable as compared to Freundlich's and BET adsorption isotherm models. CO2 is soluble in water and is reversibly formed carbonic acid. It is a weak acid since its ionization in water is incomplete. The CO2 solubility in water is estimated from the experimental results published by Wiebe and Gaddy. In most of the cases of abandoned mines, the chances of available air filled void space is limited as the level of operation is below the water table. So it is expected that the void would be completely filled with water. During this research investigation, the practical experimentation for CO2 sequestration was not within the scope. Thus, one operating mine was considered for the feasibility study. The sequestrated quantities of CO2 in terms of adsorbed volume and soluble volume were quantified. The cost of the CO2 was taken from the standard international literature. The sealing cost of the shaft was also considered. Costs of CO2 sequestration for different pressure were estimated for the mine.

49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a water... a maximum wall stress of 24,000 p.s.i. in the formula described in paragraph (f)(4) of this section... any case the minimum wall thickness must be such that the wall stress calculated by the formula listed...

49 CFR 178.61 - Specification 4BW welded steel cylinders with electric-arc welded longitudinal seam.

Code of Federal Regulations, 2010 CFR

2010-10-01

... DOT 4BW cylinder is a welded type steel cylinder with a longitudinal electric-arc welded seam, a water... a maximum wall stress of 24,000 p.s.i. in the formula described in paragraph (f)(4) of this section... any case the minimum wall thickness must be such that the wall stress calculated by the formula listed...

16 CFR § 1616.4 - Sampling and acceptance procedures.

Code of Federal Regulations, 2013 CFR

2013-01-01

... specimen to one of the three samples. Test each set of three samples and accept or reject each seam design... all the test criteria of § 1616.3(b), accept the seam design. If one or more of the three additional.... Test the sets of three samples and accept or reject the type of trim and design on the same basis as...

21 CFR 130.12 - General methods for water capacity and fill of containers.

Code of Federal Regulations, 2011 CFR

2011-04-01

... height of the double seam. (2) Measure the vertical distance from the top level of the container to the... or altering the height of the double seam. (2) Wash, dry, and weigh the empty container. (3) Fill the container with distilled water at 68 °F to 3/16 inch vertical distance below the top level of the container...

21 CFR 130.12 - General methods for water capacity and fill of containers.

Code of Federal Regulations, 2013 CFR

2013-04-01

... height of the double seam. (2) Measure the vertical distance from the top level of the container to the... or altering the height of the double seam. (2) Wash, dry, and weigh the empty container. (3) Fill the container with distilled water at 68 °F to 3/16 inch vertical distance below the top level of the container...

21 CFR 130.12 - General methods for water capacity and fill of containers.

Code of Federal Regulations, 2012 CFR

2012-04-01

... height of the double seam. (2) Measure the vertical distance from the top level of the container to the... or altering the height of the double seam. (2) Wash, dry, and weigh the empty container. (3) Fill the container with distilled water at 68 °F to 3/16 inch vertical distance below the top level of the container...

Novel pre-treatment of zeolite materials for the removal of sodium ions: potential materials for coal seam gas co-produced wastewater.

PubMed

Santiago, Oscar; Walsh, Kerry; Kele, Ben; Gardner, Edward; Chapman, James

2016-01-01

Coal seam gas (CSG) is the extraction of methane gas that is desorbed from the coal seam and brought to the surface using a dewatering and depressurisation process within the saturated coalbed. The extracted water is often referred to as co-produced CSG water. In this study, co-produced water from the coal seam of the Bowen Basin (QLD, Australia) was characterised by high concentration levels of Na(+) (1156 mg/L), low concentrations of Ca(2+) (28.3 mg/L) and Mg(2+) (5.6 mg/L), high levels of salinity, which are expected to cause various environmental problems if released to land or waters. The potential treatment of co-produced water using locally sourced natural ion exchange (zeolite) material was assessed. The zeolite material was characterized for elemental composition and crystal structure. Natural, untreated zeolite demonstrated a capacity to adsorb Na(+) ions of 16.16 mEq/100 g, while a treated zeolite using NH4 (+) using a 1.0 M ammonium acetate (NH4C2H3O2) solution demonstrated an improved 136 % Na(+) capacity value of 38.28 mEq/100 g after 720 min of adsorption time. The theoretical exchange capacity of the natural zeolite was found to be 154 mEq/100 g. Reaction kinetics and diffusion models were used to determine the kinetic and diffusion parameters. Treated zeolite using a NH4 (+) pre-treatment represents an effective treatment to reduce Na(+) concentration in coal seam gas co-produced waters, supported by the measured and modelled kinetic rates and capacity.

Seam-weld quality of modern ERW/HFI line pipe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Groeneveld, T.P.; Barnes, C.R.

1991-09-01

This study was undertaken to determine whether the seam-weld quality of modern ERW (electric resistance-welded)/HFI (high-frequency induction) welded pipe has been improved and justifies more widespread use of this type of pipe in critical applications. Wider use of ERW/HFI line pipe in gas-transmission lines would be expected to reduce construction costs. Five recently produced, heavy wall pipes fabricated using high-frequency electric-resistance welding (ERW) processes to make the seam weld and one pipe fabricated using the high-frequency induction (HFI) welding process to make the seam weld were studied. Four of the pipes were Grade X-60, one was Grade X-65, and onemore » was Grade X-70. All of the pipes were produced from microalloyed, controlled-rolled steels, and the weld zones were post-weld normalized. Ultrasonic inspection of the seam welds in the six pipe sections evaluated revealed no indications of defects. The tensile properties of all of the weld zones exceeded the minimum specified yield strengths for the respective grades of pipe and all of the pipes exhibited ductile failures either in the weld zone or in the base metal. Five of the six pipes exhibited ductile failures either in the weld zone or in the base metal. Five of the six pipes exhibited relatively low 85% shear area transition temperatures and relatively high upper-shelf energy absorptions as determined with Charpy V-notch specimens. In addition, for two of the three joints of pipe for which the properties were determined at both ends of the pipe, the tensile and impact properties showed little variation from end-to-end. However, for the other joint of pipe, the impact properties varied substantially from one end to the other.« less

Progression in sulfur isotopic compositions from coal to fly ash: Examples from single-source combustion in Indiana

USGS Publications Warehouse

Yaofa, Jiang; Elswick, E.R.; Mastalerz, Maria

2008-01-01

Sulfur occurs in multiple mineral forms in coals, and its fate in coal combustion is still not well understood. The sulfur isotopic composition of coal from two coal mines in Indiana and fly ash from two power plants that use these coals were studied using geological and geochemical methods. The two coal beds are Middle Pennsylvanian in age; one seam is the low-sulfur ( 5%) Springfield Coal Member of the Petersburg Formation. Both seams have ash contents of approximately 11%. Fly-ash samples were collected at various points in the ash-collection system in the two plants. The results show notable difference in ??34S for sulfur species within and between the low-sulfur and high-sulfur coal. The ??34S values for all sulfur species are exclusively positive in the low-sulfur Danville coal, whereas the ??34S values for sulfate, pyritic, and organic sulfur are both positive and negative in the high-sulfur Springfield coal. Each coal exhibits a distinct pattern of stratigraphic variation in sulfur isotopic composition. Overall, the ??34S for sulfur species values increase up the section in the low-sulfur Danville coal, whereas they show a decrease up the vertical section in the high-sulfur Springfield coal. Based on the evolution of ??34S for sulfur species, it is suggested that there was influence of seawater on peat swamp, with two marine incursions occurring during peat accumulation of the high-sulfur Springfield coal. Therefore, bacterial sulfate reduction played a key role in converting sulfate into hydrogen sulfide, sulfide minerals, and elemental sulfur. The differences in ??34S between sulfate sulfur and pyritic sulfur is very small between individual benches of both coals, implying that some oxidation occurred during deposition or postdeposition. The ??34S values for fly ash from the high-sulfur Springfield coal (averaging 9.7???) are greatly enriched in 34S relative to those in the parent coal (averaging 2.2???). This indicates a fractionation of sulfur isotopes during high-sulfur coal combustion. By contrast, the ??34S values for fly-ash samples from the low-sulfur Danville coal average 10.2???, only slightly enriched in 34S relative to those from the parent coal (average 7.5???). The ??34S values for bulk S determined directly from the fly-ash samples show close correspondence with the ??34S values for SO4- 2 leached from the fly ash in the low-sulfur coal, suggesting that the transition from pyrite to sulfate occurred via high-temperature oxidation during coal combustion. ?? 2007 Elsevier B.V. All rights reserved.

Scanning electron acoustic microscopy of indentation-induced cracks and residual stresses in ceramics

NASA Technical Reports Server (NTRS)

Cantrell, John H.; Qian, Menglu; Ravichandran, M. V.; Knowles, K. M.

1990-01-01

The ability of scanning electron acoustic microscopy (SEAM) to characterize ceramic materials is assessed. SEAM images of Vickers indentations in SiC whisker-reinforced alumina clearly reveal not only the radial cracks, the length of which can be used to estimate the fracture toughness of the material, but also reveal strong contrast, interpreted as arising from the combined effects of lateral cracks and the residual stress field left in the SiC whisker-reinforced alumina by the indenter. The strong contrast is removed after the material is heat treated at 1000 C to relieve the residual stresses around the indentations. A comparison of these observations with SEAM and reflected polarized light observations of Vickers indentations in soda-lime glass both before and after heat treatment confirms the interpretation of the strong contrast.

The effect of axial external magnetic field on tungsten inert gas welding of magnesium alloy

NASA Astrophysics Data System (ADS)

Li, Caixia; Zhang, Xiaofeng; Wang, Jing

2018-04-01

The influences of axial external magnetic field on the microstructure and mechanical property of the AZ31 magnesium (Mg) alloy joints were studied. The microstructure of Mg alloy joint consisted of the weld seam, heat affected zone and base metal zone. The average grain size of weld seam welded with magnetic field is 39 μm, which is 38% smaller than that of the joint welded with absence of magnetic field. And the microhardness of weld seam increases with the help of magnetic field treatment, owing to the coarse grain refinement. With coil current of 2.0A, the maximum mechanical property of joint increases 6.7% to 255 MPa over the specimen without magnetic field treatment. Furthermore, fracture location is near heat affected area and the fracture surface is characterized with ductile fracture.

Data Mining Methods Applied to Flight Operations Quality Assurance Data: A Comparison to Standard Statistical Methods

NASA Technical Reports Server (NTRS)

Stolzer, Alan J.; Halford, Carl

2007-01-01

In a previous study, multiple regression techniques were applied to Flight Operations Quality Assurance-derived data to develop parsimonious model(s) for fuel consumption on the Boeing 757 airplane. The present study examined several data mining algorithms, including neural networks, on the fuel consumption problem and compared them to the multiple regression results obtained earlier. Using regression methods, parsimonious models were obtained that explained approximately 85% of the variation in fuel flow. In general data mining methods were more effective in predicting fuel consumption. Classification and Regression Tree methods reported correlation coefficients of .91 to .92, and General Linear Models and Multilayer Perceptron neural networks reported correlation coefficients of about .99. These data mining models show great promise for use in further examining large FOQA databases for operational and safety improvements.

Spatial Variations In The Fate And Transport Of Metals In A Mining-Influenced Stream, North Fork Clear Creek, Colorado

EPA Science Inventory

North Fork Clear Creek (NFCC) receives acid-mine drainage (AMD) from multiple abandoned mines in the Clear Creek Watershed. Point sources of AMD originate In the Black Hawk/Central City region of the stream. Water chemistry also is influenced by several non-point sources of AMD,...

Science Priorities for Seamounts: Research Links to Conservation and Management

PubMed Central

Clark, Malcolm R.; Schlacher, Thomas A.; Rowden, Ashley A.; Stocks, Karen I.; Consalvey, Mireille

2012-01-01

Seamounts shape the topography of all ocean basins and can be hotspots of biological activity in the deep sea. The Census of Marine Life on Seamounts (CenSeam) was a field program that examined seamounts as part of the global Census of Marine Life (CoML) initiative from 2005 to 2010. CenSeam progressed seamount science by collating historical data, collecting new data, undertaking regional and global analyses of seamount biodiversity, mapping species and habitat distributions, challenging established paradigms of seamount ecology, developing new hypotheses, and documenting the impacts of human activities on seamounts. However, because of the large number of seamounts globally, much about the structure, function and connectivity of seamount ecosystems remains unexplored and unknown. Continual, and potentially increasing, threats to seamount resources from fishing and seabed mining are creating a pressing demand for research to inform conservation and management strategies. To meet this need, intensive science effort in the following areas will be needed: 1) Improved physical and biological data; of particular importance is information on seamount location, physical characteristics (e.g. habitat heterogeneity and complexity), more complete and intensive biodiversity inventories, and increased understanding of seamount connectivity and faunal dispersal; 2) New human impact data; these shall encompass better studies on the effects of human activities on seamount ecosystems, as well as monitoring long-term changes in seamount assemblages following impacts (e.g. recovery); 3) Global data repositories; there is a pressing need for more comprehensive fisheries catch and effort data, especially on the high seas, and compilation or maintenance of geological and biodiversity databases that underpin regional and global analyses; 4) Application of support tools in a data-poor environment; conservation and management will have to increasingly rely on predictive modelling techniques, critical evaluation of environmental surrogates as faunal “proxies”, and ecological risk assessment. PMID:22279531

Subtle structural influences on coal thickness and distribution: Examples from the Lower Broas-Stockton coal (Middle Pennsylvanian), Eastern Kentucky Coal Field, USA

USGS Publications Warehouse

Greb, S.F.; Eble, C.F.; Hower, J.C.

2005-01-01

The Lower Broas-Stockton coal is a heavily mined coal of the Central Appalachian Basin. Coal thickness, distribution, composition, and stratigraphic position were compared with basement structure, gas and oil field trends, and sequence strat- igraphic and paleoclimate interpretations to better understand the geology of the Stockton coal bed in eastern Kentucky. The thickest coal occurs south of the Warfield structural trend and east of the Paint Creek Uplift, two basement-related structures. Along the Warfield trend, coal beds in the underlying Peach Orchard coal zone locally merge with the Stockton coal to form a seam more than 3 m thick. Other areas of thick coal occur in elongate trends. Two pairs of elongate, conjugate trends in Stockton coal thickness are interpreted as regional paleofractures that influenced paleotopography and groundwater during peat accumulation. Compositional group analyses indicate that the Stockton peat infilled depressions in the paleotopography as a topogenous to soligenous mire codominated by tree ferns and lycopsid trees. Flooding from adjacent paleochannels is indicated by partings and seam splits along the margins of the mineable coal body. One or more increments of low-vitrinite coal, dominated by tree ferns and shrubby, Densosporites-producing lycopsids occur at all sample sites. Similar assemblages have been previously used to identify ombrogenous, domed mire origins for Early and Middle Pennsylvanian coals in which ash yields were less than 10%. It is difficult, however, to reconcile ombrogenous conditions with the partings in the Stockton coal in this area. Low-ash, low-vitrinite increments may have been formed in topogenous to soligenous mires with periodic drying or water-table fluctuations, rather than widespread doming. This is consistent with interpretations of increasingly seasonal paleoclimates in the late Middle and Late Pennsylvanian and fracture-influenced groundwater conditions. ??2005 Geological Society of America.

40 CFR Table 1 to Subpart Kkkk of... - Emission Limits for New or Reconstructed Affected Sources

Code of Federal Regulations, 2010 CFR

2010-07-01

... and two-piece draw and iron can body coating a. Two-piece beverage cans—all coatingsb. Two-piece food... seam stripes on food cans 1.48 (12.37). c. Nonaseptic side seam stripes on food cans 0.72 (5.96). d... Metal Cans Pt. 63, Subpt. KKKK, Table 1 Table 1 to Subpart KKKK of Part 63—Emission Limits for New or...

Novel Materials Design and Fabrication for Army Needs

DTIC Science & Technology

2012-11-01

Footwear (Dog Booties ). Each sub-project represented an Army need for improved materials and fabrication design. 1. REPORT DATE (DD-MM-YYYY) 4. TITLE...barrier seams, IOTV, patterns, stitchless seams, dog booties Dr. Christine W. Cole, Dr. Deborah K. Lickfield Clemson University Office of Sponsored...Improved OTV patterns, Textile-based options for Reduced Helmet Weight, and Canine Footwear (Dog Booties ). Each sub-project represented an Army need for

Stylolitization as source of cement in Mississippian Salem Limestone, west-central Indiana

DOE Office of Scientific and Technical Information (OSTI.GOV)

Finkel, E.A.; Wilkinson, B.H.

The Mississippian Salem Limestone of west-central Indiana is a homogeneous cross-bedded grainstone containing numerous stylolites with amplitudes ranging up to 25 cm. Petrographic and geochemical analyses of closely spaced samples from four 1-m thick stylolite-bounded units document spatial trends in grainstone texture and composition, which correlate with proximity to bounding solution seams. Textural data indicate that stylolitization was locally preceded by grain compaction and that seam solution preferentially occurred within layers where grain packing was tightest. Amount of cement largely corresponds to volume of available pore space, and remaining porosity varies inversely to stylolite proximity. Trace-element compositions demonstrate that intergranularmore » spar is enriched in Mn and depleted in Mg relative to grains, and suggest a significant contribution of carbonate cement to grainstone pores from bounding solution seams. Data on grainstone and stylolite insoluble contents indicate that stylolite amplitude records 43% of actual section shortening. On average, seam solution within the Salem Limestone could have provided no less than 47% and no more than 90% of the CaCO{sub 3}, Fe, and Mn mass now in grainstone pores as intergranular spar cement. As such, stylolitization has played an important role during burial diagenesis, porosity occlusion, and permeability reduction within this Mississippian grainstone sequence. 17 figs., 1 tab.« less

On the description of conical intersections—A continuous representation of the local topography of seams of conical intersection of three or more electronic states: A generalization of the two state result

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhu, Xiaolei, E-mail: virtualzx@gmail.com; Yarkony, David R., E-mail: yarkony@jhu.edu

2014-11-07

For conical intersections of two states (I,J = I + 1) the vectors defining the branching or g-h plane, the energy difference gradient vector g{sup I,J}, and the interstate coupling vector h{sup I,J}, can be made orthogonal by a one parameter rotation of the degenerate electronic eigenstates. The representation obtained from this rotation is used to construct the parameters that describe the vicinity of the conical intersection seam, the conical parameters, s{sup I,J}{sub x} (R), s{sup I,J}{sub y} (R), g{sup I,J}(R), and h{sup I,J}(R). As a result of the orthogonalization these parameters can be made continuous functions of R, themore » internuclear coordinates. In this work we generalize this notion to construct continuous parametrizations of conical intersection seams of three or more states. The generalization derives from a recently introduced procedure for using non-degenerate electronic states to construct coupled diabatic states that represent adiabatic states coupled by conical intersections. The procedure is illustrated using the seam of conical intersections of three states in parazolyl as an example.« less

Structural pathway of regulated substrate transfer and threading through an Hsp100 disaggregase.

PubMed

Deville, Célia; Carroni, Marta; Franke, Kamila B; Topf, Maya; Bukau, Bernd; Mogk, Axel; Saibil, Helen R

2017-08-01

Refolding aggregated proteins is essential in combating cellular proteotoxic stress. Together with Hsp70, Hsp100 chaperones, including Escherichia coli ClpB, form a powerful disaggregation machine that threads aggregated polypeptides through the central pore of tandem adenosine triphosphatase (ATPase) rings. To visualize protein disaggregation, we determined cryo-electron microscopy structures of inactive and substrate-bound ClpB in the presence of adenosine 5'- O -(3-thiotriphosphate), revealing closed AAA+ rings with a pronounced seam. In the substrate-free state, a marked gradient of resolution, likely corresponding to mobility, spans across the AAA+ rings with a dynamic hotspot at the seam. On the seam side, the coiled-coil regulatory domains are locked in a horizontal, inactive orientation. On the opposite side, the regulatory domains are accessible for Hsp70 binding, substrate targeting, and activation. In the presence of the model substrate casein, the polypeptide threads through the entire pore channel and increased nucleotide occupancy correlates with higher ATPase activity. Substrate-induced domain displacements indicate a pathway of regulated substrate transfer from Hsp70 to the ClpB pore, inside which a spiral of loops contacts the substrate. The seam pore loops undergo marked displacements, along with ordering of the regulatory domains. These asymmetric movements suggest a mechanism for ATPase activation and substrate threading during disaggregation.

Communication: Multiple-property-based diabatization for open-shell van der Waals molecules

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karman, Tijs; Avoird, Ad van der; Groenenboom, Gerrit C., E-mail: gerritg@theochem.ru.nl

2016-03-28

We derive a new multiple-property-based diabatization algorithm. The transformation between adiabatic and diabatic representations is determined by requiring a set of properties in both representations to be related by a similarity transformation. This set of properties is determined in the adiabatic representation by rigorous electronic structure calculations. In the diabatic representation, the same properties are determined using model diabatic states defined as products of undistorted monomer wave functions. This diabatic model is generally applicable to van der Waals molecules in arbitrary electronic states. Application to locating seams of conical intersections and collisional transfer of electronic excitation energy is demonstrated formore » O{sub 2} − O{sub 2} in low-lying excited states. Property-based diabatization for this test system included all components of the electric quadrupole tensor, orbital angular momentum, and spin-orbit coupling.« less

Characterization and Recovery of Rare Earths from Coal and By-Products

DOE Office of Scientific and Technical Information (OSTI.GOV)

Granite, Evan J.; Roth, Elliot; Alvin, Mary Anne

Coal is a precious resource, both in the United States and around the world. The United States has a 250-year supply of coal, and generates between 30 - 40% of its electricity through coal combustion. Approximately 1 Gt of coal has been mined annually in the US, although the 2015 total will likely be closer to 900 Mt (http://www.eia.gov/coal/production/quarterly/). Most of the coal is burned for power generation, but substantial quantities are also employed in the manufacture of steel, chemicals, and activated carbons. Coal has a positive impact upon many industries, including mining, power, rail transportation, manufacturing, chemical, steel, activatedmore » carbon, and fuels. Everything that is in the earth’s crust is also present within coal to some extent, and the challenge is always to utilize abundant domestic coal in clean and environmentally friendly manners. In the case of the rare earths, these valuable and extraordinarily useful elements are present within the abundant coal and coal by-products produced domestically and world-wide. These materials include the coals, as well as the combustion by-products such as ashes, coal preparation wastes, gasification slags, and mining by-products. All of these materials can be viewed as potential sources of rare earth elements. Most of the common inorganic lanthanide compounds, such as the phosphates found in coal, have very high melting, boiling, and thermal decomposition temperatures, allowing them to concentrate in combustion and gasification by-products. Furthermore, rare earths have been found in interesting concentrations in the strata above and below certain coal seams. Much of the recent research on coal utilization in the United States has focused upon the capture of pollutants such as acid gases, particulates, and mercury, and the greenhouse gas carbon dioxide. The possible recovery of rare earth and other critical elements from abundant coal and by-products is an exciting new research area, representing a dramatic paradigm shift for coal.« less

Collaborative Data Mining

NASA Astrophysics Data System (ADS)

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.

Rare Earth Elements of Orzeskie Beds of South-West Part Upper Silesian Coal Basin (Poland) / Pierwiastki Ziem Rzadkich Z Pokładów Węgla Warstw Orzeskich Południowo-Zachodniej Części Gzw (Polska)

NASA Astrophysics Data System (ADS)

Adamczyk, Zdzisław; Białecka, Barbara; Moszko, Joanna Całusz; Komorek, Joanna; Lewandowska, Małgorzata

2015-03-01

The subject of the research concerned the coal samples from 360/1, 361 and 362/1 seams of the Orzesze beds in the "Pniówek" coal mine. The obtained samples were characterized by low ash content - 2.22- 6.27% of the mass. The chemical composition of the ash indicates the presence of aluminosilicate minerals in the analyzed coal samples - most likely clay minerals, the presence of which has been confirmed in microscopic tests of the petrographic composition of channel samples of coal. The content of rare earth elements (REE sum) in the ash of the tested coal seams ranged from 364 to 1429 ppm. Variation of the REE content has been observed within a single seam. The fraction of REE indicates a relation with a mineral substance. No relation of the REE fraction and the presence of red beds has been found based on the tested samples. The content of REE found in ash, normalized to chondrites, is characterized by LREE enrichment in relation to HREE. The Eu anomaly is most likely related to tuff and tonstein levels occurring in Orzesze beds, which accompany the coal seams in the Upper Silesian Coal Basin (i.a., south of the studied area). The research has indicated that LREE in the tested samples are more related to the mineral substance, while HREE have a stronger affinity with organic substances. Przedmiotem badań były próbki węgla z pokładów 360/1, 361 i 362/1 warstw orzeskich KWK Pniówek. Próbki te charakteryzują się niewielką zawartością popiołu 2,22-6,27% mas. Skład chemiczny popiołów wskazuje na obecność w analizowanych próbkach węgla minerałów z grupy glinokrzemianów najprawdopodobniej minerałów ilastych, których obecność była stwierdzona w badaniach mikroskopowych składu petrograficznego próbek bruzdowych węgla. Zawartości pierwiastków ziem rzadkich (suma REE) w popiołach badanych pokładów węgla wahają się od 364 do 1429 ppm. Obserwuje się zróżnicowanie zawartości REE w obrębie jednego pokładu. Udział REE wykazuje związek z substancją mineralną. Nie stwierdzono związku udziału REE, w badanych próbkach, z obecnością utworów pstrych w stropie karbonu. Zawartości REE oznaczone w popiołach, znormalizowane do chondrytów, charakteryzują się wzbogaceniem LREE wobec HREE. Anomalia Eu związana jest prawdopodobnie z występującymi w warstwach orzeskich (m.in. na północ od obszaru badań) Górnośląskiego Zagłębia Węglowego poziomami tufów i tonsteinów, które towarzyszą pokładom węgla. Badania wykazały, że LREE w badanych próbkach związane są raczej z substancją mineralną, natomiast HREE posiadają silniejsze powinowactwo z substancją organiczną.

COVERING THE SEAMS IN U.S. NATIONAL SECURITY BY APPLYING NETWORK AND TEAM ATTRIBUTES

DTIC Science & Technology

2017-04-06

Today, one such weakness is the seams that exist in the system . Organizational criteria like geography , functions, and responsibilities often create...establishment by the National Security Act of 1947, the modern U.S. national security system has evolved as a result of legislation, presidential preference...and because of changes in the U.S. and international security environments. With each evolution, the system has found ways to function in dealing

Automatic pickup of arrival time of channel wave based on multi-channel constraints

NASA Astrophysics Data System (ADS)

Wang, Bao-Li

2018-03-01

Accurately detecting the arrival time of a channel wave in a coal seam is very important for in-seam seismic data processing. The arrival time greatly affects the accuracy of the channel wave inversion and the computed tomography (CT) result. However, because the signal-to-noise ratio of in-seam seismic data is reduced by the long wavelength and strong frequency dispersion, accurately timing the arrival of channel waves is extremely difficult. For this purpose, we propose a method that automatically picks up the arrival time of channel waves based on multi-channel constraints. We first estimate the Jaccard similarity coefficient of two ray paths, then apply it as a weight coefficient for stacking the multichannel dispersion spectra. The reasonableness and effectiveness of the proposed method is verified in an actual data application. Most importantly, the method increases the degree of automation and the pickup precision of the channel-wave arrival time.

Automatic weld torch guidance control system

NASA Technical Reports Server (NTRS)

Smaith, H. E.; Wall, W. A.; Burns, M. R., Jr.

1982-01-01

A highly reliable, fully digital, closed circuit television optical, type automatic weld seam tracking control system was developed. This automatic tracking equipment is used to reduce weld tooling costs and increase overall automatic welding reliability. The system utilizes a charge injection device digital camera which as 60,512 inidividual pixels as the light sensing elements. Through conventional scanning means, each pixel in the focal plane is sequentially scanned, the light level signal digitized, and an 8-bit word transmitted to scratch pad memory. From memory, the microprocessor performs an analysis of the digital signal and computes the tracking error. Lastly, the corrective signal is transmitted to a cross seam actuator digital drive motor controller to complete the closed loop, feedback, tracking system. This weld seam tracking control system is capable of a tracking accuracy of + or - 0.2 mm, or better. As configured, the system is applicable to square butt, V-groove, and lap joint weldments.

Crocoite: An unusual mode of occurence for lead in coal

USGS Publications Warehouse

Li, Z.; Moore, T.A.; Weaver, S.D.; Finkelman, R.B.

2001-01-01

What is believed to be a very unusual mode of occurrence for lead in coal has been identified as crocoite (PbCrO4). As part of a larger study on trace elements and mineralogy in the Cretaceous Main Seam in New Zealand, crocoite was found in raw coal samples within the lower part of the coal seam. X-ray diffraction (XRD) and bulk chemical data from a SEM equipped with an energy dispersive X-ray analyser (EDXA) have confirmed the identity of this mineral. This is apparently the first time that crocoite has been reported in coal. Crocoite usually occurs only in the oxidised zone of lead mineral deposits. The occurrence of this mineral in the Main Seam coal implies that the deposit was exposed to an oxidising environment at some stage, most likely after coalification. Published by Elsevier Science B.V.

Laser Ablation Cleaning of Self-Reacting Friction Stir Weld Seam Surfaces: A Preliminary Evaluation

NASA Technical Reports Server (NTRS)

Nunes, A. C., Jr.; Russell, C. K.; Brooke, S. A.; Parry, Q.; Lowrey, N. M.

2014-01-01

Anodized aluminum panels were cleaned by three lasers at three separate sites with a view to determining whether more economical laser cleaning might supplant current manual cleaning methods for preparation of surfaces to be welded by the self-reacting friction stir process. Uncleaned panels yielded welds exhibiting residual oxide defect (ROD) and failing at very low stresses along the trace of the weld seam. Manually cleaned panels yielded welds without ROD; these welds failed at nominal stress levels along an angled fracture surface not following the weld seam trace. Laser cleaned panels yielded welds failing at intermediate stress levels. The inadequacy of the laser cleaning processes leaves questions: Was the anodized aluminum test too stringent to represent actual cleaning requirements? Were the wrong laser cleaning techniques/parameters used for the study? Is the laser cleaning mechanism inadequate for effective preweld surface cleaning?

A novel orthoimage mosaic method using the weighted A* algorithm for UAV imagery

NASA Astrophysics Data System (ADS)

Zheng, Maoteng; Zhou, Shunping; Xiong, Xiaodong; Zhu, Junfeng

2017-12-01

A weighted A* algorithm is proposed to select optimal seam-lines in orthoimage mosaic for UAV (Unmanned Aircraft Vehicle) imagery. The whole workflow includes four steps: the initial seam-line network is firstly generated by standard Voronoi Diagram algorithm; an edge diagram is then detected based on DSM (Digital Surface Model) data; the vertices (conjunction nodes) of initial network are relocated since some of them are on the high objects (buildings, trees and other artificial structures); and, the initial seam-lines are finally refined using the weighted A* algorithm based on the edge diagram and the relocated vertices. The method was tested with two real UAV datasets. Preliminary results show that the proposed method produces acceptable mosaic images in both the urban and mountainous areas, and is better than the result of the state-of-the-art methods on the datasets.

Differentiation of closely related isomers: application of data mining techniques in conjunction with variable wavelength infrared multiple photon dissociation mass spectrometry for identification of glucose-containing disaccharide ions.

PubMed

Stefan, Sarah E; Ehsan, Mohammad; Pearson, Wright L; Aksenov, Alexander; Boginski, Vladimir; Bendiak, Brad; Eyler, John R

2011-11-15

Data mining algorithms have been used to analyze the infrared multiple photon dissociation (IRMPD) patterns of gas-phase lithiated disaccharide isomers irradiated with either a line-tunable CO(2) laser or a free electron laser (FEL). The IR fragmentation patterns over the wavelength range of 9.2-10.6 μm have been shown in earlier work to correlate uniquely with the asymmetry at the anomeric carbon in each disaccharide. Application of data mining approaches for data analysis allowed unambiguous determination of the anomeric carbon configurations for each disaccharide isomer pair using fragmentation data at a single wavelength. In addition, the linkage positions were easily assigned. This combination of wavelength-selective IRMPD and data mining offers a powerful and convenient tool for differentiation of structurally closely related isomers, including those of gas-phase carbohydrate complexes.

Application of least-squares fitting of ellipse and hyperbola for two dimensional data

NASA Astrophysics Data System (ADS)

Lawiyuniarti, M. P.; Rahmadiantri, E.; Alamsyah, I. M.; Rachmaputri, G.

2018-01-01

Application of the least-square method of ellipse and hyperbola for two-dimensional data has been applied to analyze the spatial continuity of coal deposits in the mining field, by using the fitting method introduced by Fitzgibbon, Pilu, and Fisher in 1996. This method uses 4{a_0}{a_2} - a_12 = 1 as a constrain function. Meanwhile, in 1994, Gander, Golub and Strebel have introduced ellipse and hyperbola fitting methods using the singular value decomposition approach. This SVD approach can be generalized into a three-dimensional fitting. In this research we, will discuss about those two fitting methods and apply it to four data content of coal that is in the form of ash, calorific value, sulfur and thickness of seam so as to produce form of ellipse or hyperbola. In addition, we compute the error difference resulting from each method and from that calculation, we conclude that although the errors are not much different, the error of the method introduced by Fitzgibbon et al is smaller than the fitting method that introduced by Golub et al.

Automatic mine detection based on multiple features

NASA Astrophysics Data System (ADS)

Yu, Ssu-Hsin; Gandhe, Avinash; Witten, Thomas R.; Mehra, Raman K.

2000-08-01

Recent research sponsored by the Army, Navy and DARPA has significantly advanced the sensor technologies for mine detection. Several innovative sensor systems have been developed and prototypes were built to investigate their performance in practice. Most of the research has been focused on hardware design. However, in order for the systems to be in wide use instead of in limited use by a small group of well-trained experts, an automatic process for mine detection is needed to make the final decision process on mine vs. no mine easier and more straightforward. In this paper, we describe an automatic mine detection process consisting of three stage, (1) signal enhancement, (2) pixel-level mine detection, and (3) object-level mine detection. The final output of the system is a confidence measure that quantifies the presence of a mine. The resulting system was applied to real data collected using radar and acoustic technologies.