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Results 21 - 30 of 58
11/1/2007 - Peer reviewed journal articlesA discussion the spatio-temporal volumetric strains in a consolidated Pittsburgh seam coal sample which were evaluated while both confining pressure and carbon dioxide CO2 pore pressure were evaluated.
Reservoir Simulation-Based Modeling for Characterizing Longwall Methane Emissions and Gob Gas Venthole Production7/1/2007 - Peer reviewed journal articlesThis paper presents the development and results of a comprehensive, "dynamic," three-dimensional reservoir model of a typical multi-panel Pittsburgh coalbed longwall mine. Results presented in this paper include a simulation of gas flow patterns from th...
Development and Application of Reservoir Models for the Evaluation and Optimization of Longwall Methane Control Systems6/1/2006 - Conference papersThis paper describes the development of reservoir models for the longwall mining environment and their application for investigating the influence of various completion design parameters on the methane drainage effectiveness of gob gas ventholes.
5/1/1999 - Conference papersInvestigation of the geologic and mining factors influencing the migration of longwall gob gas with a goal to optimize methane drainage strategies to reduce the volume of gob gas that reaches the underground workplace.
3/1/1995 - Technology NewsThe absence of fundamental scientific and engineering principles in the design and placement of gob gas ventholes can cause difficulties for mine operators when gas emissions increase because of a change in mine design or because variable geologic condi...
1/1/1992 - Reports of InvestigationsFour coreholes were drilled at a longwall mine in the Lower Kittanning coalbed to obtain coal and rock samples from overlying strata to determine their gas content during the mining cycle. Test results indicate that 91% of the gas came from coalbeds.
1/1/1989 - Reports of InvestigationsThe U.S. Bureau of Mines used a contact drilling strategy with short-collared assemblies in order to rotary drill long horizontal methane drainage holes in the Beckley coalbed near Glen Daniel, West Virginia. By decreasing the thrust and increasing the ...
1/1/1987 - Reports of InvestigationsGob holes are routinely used by the mining industry to vent methane from gobs and to prevent it from entering the mine ventilation system. In some cases, flows from gob holes are measured by centering an anemometer on the end of a discharge pipe. These ...
1/1/1986 - Reports of InvestigationsThe Bureau of Mines conducted studies to compare the effectiveness of the cross-measure borehole system with that of surface gob holes on two successively mined retreating longwalls in the Lower Kittanning coalbed. Only the cross-measure system was in o...
1/1/1985 - Reports of InvestigationsThe cross-measure borehole technique is an effective method of controlling methane liberated by fracturing the roof strata in longwall gobs where overburden is less than 750 ft (229 m). About 71 pct of the methane produced by longwall mining in the Lowe...