نتایج جستجو برای: Coal

تعداد نتایج: 31950  

پایان نامه :وزارت علوم، تحقیقات و فناوری - دانشگاه صنعتی اصفهان 1389

در این پژوهش، ساخت ترکیب بین فلزی coal نانوساختار و نانوکامپوزیت های coal/al2o3 با درصدهای مختلف از ذرات تقویت کننده به روش آلیاژسازی مکانیکی مورد بررسی قرار گرفت. تغییرات فازی و مطالعات ریزساختاری به وسیله آزمون های پراش پرتو ایکس (xrd)، میکروسکوپ الکترونی روبشی (sem)، میکروسکوپ الکترونی عبوری (tem) و آنالیز حرارتی (dta) ارزیابی شد. نتایج نشان داد که آلیاژسازی مکانیکی مخلوط پودری co50al50 موجب...

Journal: :int. journal of mining & geo-engineering 2013
amir saffari farhang sereshki mohammad ataei keramat ghanbari

subject analysis of the potential of spontaneous combustion in coal layers with analytical and numerical methods has been always considered as a difficult task because of the complexity of the coal behavior and the number of factors influencing it. empirical methods, due to accounting for certain and specific factors, have not accuracy and efficiency for all positions. the rock engineering syst...

Spontaneous combustion of coal is one of the most horrifying hazards in coal industries, especially in underground coal mines. Thus having a prior knowledge about the occurrence of this phenomenon in underground coal mines is of crucial importance in preventing this process, loss of life, huge economic loss, and environmental pollution. The aim of this work is to determine the spontaneous combu...

A. A. Elahi

As a tool for exploration of concealed coal seams by modern techniques, determination of the depth of erosion of coal seams with reference to the surface of angular unconformity underlying the remnants of a key bed is conducted for the first time in coal mines of Kerman region. The angular unconformity surface (the initial surface exposure of coal seams) separates the coal seams of Jurassic age...

Journal: :iranian journal of chemistry and chemical engineering (ijcce) 2007
mohammad reza ehsani farahnaz eghbali

tabas mines in iran have coal sources which are suitable for use in metallurgy industries as coking coal. but the high sulfur content of this coal imposes severe limitations on its utilization as the sulfur oxide gases evolved from the combustion of high sulfur coals result in acid rains and corrosion of equipments. in this work, attempts have been made to reduce sulfur from high sulfur coal of...

Journal: :journal of mining and environment 2010
n. i. aziz i. porter f. sereshki

the volumetric changes in the coal matrix (coal shrinkage), permeability under various gas environment conditions as well as perographical properties were studied in the laboratory. the shrinkage and permeability of coal were examined with respect to changing gas type and confining pressures. the shrinkage tests were carried out in high-pressure bombs while the permeability study was conducted ...

F. Sereshki, I. Porter , N. Aziz , S.A. Hosseini,

The Outburst can be defined as a sudden release of coal and rock accompanied by large quantities of gas into the underground coal mine workings which represents a major hazard in underground coal mines. Gas drainage has been proven to be successful in reducing outburst hazards by decreasing the in-situ gas pressure. One of aspect of gas drainage from coal seams is coal matrix volume changes. Cu...

رقیمی, مصطفی, شمعانیان, غلامحسین, قلی پور, محسن, مظاهری, سید احمد,

This study mostly investigated the environmental impact of acid mine drainage (AMD) on the tailing of coal cleaning factory in Mazandaran province. This factory is one of the largest and the oldest in the coal concentration in Central Alborze Coal Basin. So, annually huge amounts of coal tailing will be left. The sampling of coal, coal tailing, drainage water from coal tailing, factory's waste ...

Journal: :iranian journal of chemistry and chemical engineering 0
raheel ahmad department of chemical engineering, university of engineering and technology, g.t. rd, lahore 54890, pakistan iqra saleem department of chemical engineering, university of engineering and technology, g.t. rd, lahore 54890, pakistan

clean hydrogen is the major energy carrier for power production. the conversion of co to co2 and zero emission during hydrogen energy production causes high capital cost. it is a matter of prestige to optimize the process in order to make zero emission and cost effective production of clean hydrogen energy and electric power. in this era, coal gasification is the most promising technology for t...

There are several phenomenons for polluting the environment, especially in coalfields; which coal spontaneous combustion is one of them. The moisture content is one of the intrinsic characteristics of coal, which has an important role in the occurrence of this phenomenon. Therefore, this research predicts the coal spontaneous combustion tendency based on moisture content. The percentage of mois...

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