IJSRSET1622433 | Received : 01 May 2016 | Accepted : 05 May 2016 | March-April 2016 [(2)2: 1297-1301]
© 2016 IJSRSET | Volume 2 | Issue 2 | Print ISSN : 2395-1990 | Online ISSN : 2394-4099
Themed Section: Engineering and Technology
1297
ACID Mine Drainage : A Case Study of An Indian Coal Mine
Apurva Vyawahre
1
, Srijana Rai
2
1
B.Tech Civil, Visvesvarya National Institute of Technology, Nagpur, Maharashtra, India
2
Coal India Ltd., B.Tech Civil, Visvesvarya National Institute of Technology, Nagpur, Maharashtra, India
ABSTRACT
Water is essential to life on our planet. A prerequisite of sustainable development must be to ensure uncontaminated
streams, rivers, lakes and oceans. We often take the presence of clean water for granted, forgetting its importance
and assuming that it is always available. Unfortunately, the law and technology to protect this vital resource remains
far from perfect. Increasingly, human activities threaten the water sources on which we all depend. Mining is one
such activity. In fact, water has been called "mining's most common casualty."
This paper discusses one of the major negative impacts that the mining industry has on water i.e. Acid Mine
Drainage (AMD), the chemistry of AMD, its environmental effects and impacts and a brief discussion about various
treatment methods. Further a case study from India of an Effluent Treatment Plant (ETP) has been used to describe
three of the treatment methods in details and the results of this ETP. Finally concluding with suggestions to improve
the existing plant and overall AMD Treatment in Indian Mines.
Keywords: Acid Mine Drainage, Coal Mines, Effluent Treatment Plant.
I. INTRODUCTION
Coal mining has severe impacts on the environment that
go well beyond the problem of production of CO
2
generally associated with the use of coal. Mining deeply
affects air, water and land resources. Due to mining, dust
and methane, sulphur dioxide (SO
2
), oxides of nitrogen,
CO and other gases are spread in the air, thus affecting
water and land resources, as well as human health.
These are consequences of underground mining and,
even more, of opencast operations. Another source of
damage related to mining is fires in the mines, which are
frequent and have severe consequences not only for the
environment and the safety of the workers, but also for
the production itself. The impact of mining and
associated activities on water resources is also difficult.
Mining requires large amounts of water, diminishing the
quantity available for other purposes. Furthermore, both
underground and opencast mining disturbs aquifers and
water table.
The main pollutants associated with mining are
suspended solids, dissolved salts, acidity and iron
compounds. One of the major problems related to coal
mining and water pollution is Acid Mine Drainage
(AMD), the outflow of acidic water from coal mines.
Overburden is rocks that must be removed, so the ore
can be mined and processed to obtain the metal for
commercial purposes. Many metals occur in nature in
the sulfide minerals form. When the ore mined and rock
covers that contain sulfides are exposed to the open air,
then water, oxygen and bacteria reacts to produce
solution of sulfuric acid. The acidic water can dissolve
metals contained in the cover rocks and cause adverse
environmental impacts to the water bodies if not
managed properly. This process is known as acid mine
drainage. Acid mine drainage is formed from rocks that
contain minerals mine sulfide and oxygen through
contact with air and water. Acid mine drainage are
characterized by lower pH, increasing levels of sulphate,
shed and bring the heavy metal content. Indications of
acid mine drainage in coal mining area is the appearance
of the precipitate or yellow-orange in mine water flow,
the sulfur odor, and acidity of the soil.