Water pollution from coal mining

Water pollution from boiler operations (thermal pollution), surface or ground-water contamination from mining of coal and limestone... 

Similar reactions are also possible with a variety of other sulfide minerals such as galena (PbS) and sphalerite (ZnS). These reactions produce acid mine water, a major pollution problem from coal mining. 

Acid mine drainage (see Chapter 4) is an environmentally important pollutant that results from bacterial action on iron compounds from coal mines. Acid mine water, due to the presence of sulfuric... 

Mine waters occupy a special place in corrosion studies considering their widely varying composition from mine to mine. Because of its low cost, availability and ease of fabrication, mild steel is widely used as a structural material in mining equipment, although it can experience rapid and catastrophic corrosion failure when in contact with polluted acid mine waters. Specifically in coal mines, corrosion is known to be a serious problem. ... 

F. ferro-oxidants is capable of accelerating the oxidation of pyritic (FeSj) deposits at acid pH values. It is usually found in association with Thio-bacillus and was known as Thiobacillus ferroxidans before the distinction between the two organisms was appreciated. It is responsible for pollution problems arising from acid waters in gold and bituminous coal mines such waters are corrosive to pumping machinery and mining installations (see Fig. 2.20). 

Chaulya, S. K., Chkraborty, M. K., Ahmad, M., Singh, R. S., Bondyopadhay, C., Mondal, G. C. Pal, D. 2002. Development of empirical formulae to determine emission rate from various opencast coal mining operations. Water Air and Soil Pollution, 140, 21-55. 

Wood, S. C., Younger, P. L. Robins, N. S. 1999. Long-term changes in the quality of polluted mine-water discharges from abandoned underground coal workings in Scotland. Quarterly Journal of... 

Thirty-four minor and trace elements are of potential environmental concern (n ). Sulfur is the element of major concern due to its abundance in flue gases from some coal-burning plants and its subsequent contribution to "acid rain." Sulfur as acidic ions of sulfate can also contribute to pollution of surface water and groundwater. Other elements of greatest concern are As, B, Cd, Pb, Hg, Mo, and Se. With the exception of B and Se, these elements are strongly associated with mineral matter in the coal and are concentrated in waste piles from coal preparation plants. If the waste disposal site is not constructed as a closed system, pollution of nearby groundwater is possible. Boron and Se may contribute to the pollution risk as they are associated with both mineral and organic components. On the other hand, certain coal-mine wastes have potential for recovery of valuable metals such as zinc and cadmium (18). 

Mercury is. of course, a naturally occurring element. However. industrial pollution is a major source of environmental mercury. The pollution comes from many sources, such as coal-burning power plants, rclinertes. runc from factories, and industrial waste. Mercury also enters the environment from such sources as automobile exhausts, sewage treatment plants, medical and dental facilities, and water runoff from mercury and gold-mining operations. The Clean Air Act, first enacted in 1970 in the United Stales, mandated levels of air pollution, including mercury. Likewise, the EPA has set water-quality criteria for levels of mercury in both fresh and saltwater systems, The Clean Water Act requires that individual slates achieve safe concentration levels for pollutants like mercury. 

In addition to air, water, and soil pollution, large quantities of solid and liquid wastes generated by both industry and domestic use must be remediated, recycled, or contained. Industrial wastes include overburden and tailings from mining, milling, and refining, as well as residues from coal-fired steam plants and the wastes... 

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