Mercury Air Pollution from Coal Combustion in India and Its Control Measures

Abstract

Mercury exists in the earth’s crust mostly as cinnabar (HgS) and hence is present as an impurity in most of the fuel and minerals. Coal is the primary fuel source for 40.7% of the world according to 2014 data. In recent years, there is a decline in coal usage in countries like Europe, USA, and China. However, India’s energy consumption has doubled since year 2000 with coal being the major fuel source. With the rising coal demand, India is predicted to be the largest coal importer in the world before 2020. Mercury content in coal varies from 0.05 to 0.2 g/MT according to the United Nations Environmental Program’s mercury estimation toolkit. Mercury pollution monitoring and its intercontinental transport modeling done for Arctic region concludes that 32% of this pollution originated from the Asian countries. Various world mercury emission estimates done in the past researches consider India to be the second largest mercury emitter after China. Last mercury emission estimate for India was done in the year 2004. This paper compares the mercury emissions from coal combustion in India to that of the world and studies the effectiveness of various air pollution control devices in the removal of mercury from coal combustion emissions.