نتایج جستجو برای: coal mining
تعداد نتایج: 114364 فیلتر نتایج به سال:
Coalbed methane (CBM) plays an important role in coal mining safety and natural gas production. In this work, The CBM potential of B2 seam in Parvadeh IV coal deposit, in central Iran, was evaluated using a combination of local regression and geostatistical methods. As there were 30 sparse methane sampling points in the Parvadeh IV coal deposit, no valid variogram was achieved for the methane c...
Self-ignited, naturally occurring coal fires and fires resulting from human activities persist for decades in underground coal mines, coal waste piles, and unmined coal beds. These uncontrolled coal fires occur in all coal-bearing parts of the world (Stracher, 2007) and pose multiple threats to the global environment because they emit greenhouse gases—carbon dioxide (CO2), and methane (CH4)—as ...
coalbed methane (cbm) plays an important role in coal mining safety and natural gas production. in this work, the cbm potential of b2 seam in parvadeh iv coal deposit, in central iran, was evaluated using a combination of local regression and geostatistical methods. as there were 30 sparse methane sampling points in the parvadeh iv coal deposit, no valid variogram was achieved for the methane c...
Nowadays we can observe the change of the structure of energy resources, which leads to the increasing fraction of a renewable energy sources. Traditional underground coal mining loses its significance in a total but there are countries, including Poland, which economy is still coal based. A decreasing coal resources imply an exploitation a becoming harder accessible coal beds what is connected...
The increasing trend of opencast coal mining in India tends to release huge amounts of dust. But there is no well-defined method of estimating dust emission due to different coal mining activities. This paper examines the sources of dust emission due to coal mining activities, and focuses on the quantification of dust emission with the development and use of emission factors. Because of their s...
BACKGROUND Prior to 1970, coal mining technology and prevention measures in China were poor. Mechanized coal mining equipment and advanced protection measures were continuously installed in the mines after 1970. All these improvements may have resulted in a change in the incidence of coal workers' pneumoconiosis (CWP). Therefore, it is important to identify the characteristics of CWP today and ...
Information on radiographic evidence of coal workers' pneumoconiosis (CWP) is presented for a group of 3,194 underground bituminous coal miners and ex-miners examined between 1985 and 1988. Prevalence of CWP was related to estimated cumulative dust exposure, age, and rank of coal. On the basis of these data, miners of medium to low rank coal, who work for 40 years at the current federal dust li...
The conventional practice in open cut coal strip mining has been to blast the overburden or coal layers in separate blast events. This is done in order to maximise the benefits from throw blasting and also to limit coal losses. Each blast event usually has a particular design of hole diameters, burdens and spacings, explosive charges and blast timing in order to achieve the required blast outco...
Assessing the impact of opencast coal mining on water quality Executive Summary The European Directive on Groundwater (80/68/EEC) was fully transposed into Scottish law by the introduction of the Groundwater Regulations 1998. These regulations forbid the introduction of certain substances (denoted as "List I substances") into groundwater, and also place limitations on the extent to which other ...
This research presents data on widespread abnormal accumulations of Trace and Rare Earth Elements in many coal deposits worldwide. There have been many studies on the distribution and geochemistry of REEs in coal. ∑REE content in most coals varies from several µg/g to several hundred µg/g, and the REEs are distributed in minerals although some are associated with organic material in coal. In th...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید