Clean coal technology—a technical response to the environmental challenges

Abstract

Coal occurs in 70 countries of the world. Total proved reserve of coal in the world is about 909 billion tonnes. India contributes about 105 billion tonnes of proven coal reserves and ranks fourth in the world after USA, Russia and China. India is also the third largest producer of coal in the world, producing about 400 million tonnes annually. Jharkhand has 39480 million tonnes of proved coal reserve and ranks first in the country. Coal produces 40% of the world’s electricity and around 70% of the world’s steel. Coal is used in cement, paper, chemical, pharmaceutical industries and also used as liquid fuel in transportation and electricity. Coal is mined in over 50 countries and 7 million people are employed in coal mining sector. In developing countries the coal industry is export oriented and is a major source of foreign currency. Thus, coal makes a significant contribution to global economic development. Beside above facts mining of coal and its uses in different industries have a number of adverse environmental impacts. Use of coal causes emissions of oxides of nitrogen and sulphur, ash, trace elements and carbon dioxide. Ash from coal combustion can effect people’s respiratory systems and it also impacts local visibility. This ash also causes environmental pollution. Emissions of trace elements like selenium and arsenic can be harmful to human health and the environment. During the combustion process NO2 and SO2 gas formed and it can increase ground level ozone, acid rain, green house effect, smog and acidic aerosols. Similarly, coal mining, particularly surface mining, also raises a number of environmental challenges like soil erosion, dust, noise and water pollution etc. which has an impact on local biodiversity.