Process of acid mine drainage geochemical and microbial reactions during weathering of sulfide minerals pyrite in coal, refuse, or mine overburden oxidation of sulfide minerals in the presence of air, water, and bacteria formation of sulfuric acid and increase in acidity solubilization of metals due to low ph 5. Acid mine drainage amd is one of most significant environmental challenges facing the mining industry. The major areas of research on amd are prediction of amd and preventionmitigation. The following is an overview of information on some major. Acid rock drainage ard is produced by the oxidation of sulfide minerals, chiefly iron pyrite or iron. Acid mine drainage amd, also is a natural occurrence resulting from the. Pdf acid mine drainage formation, control and treatment. Acid mine drainage, acid and metalliferous drainage amd, or acid rock drainage ard is the outflow of acidic water from metal mines or coal mines acid rock drainage occurs naturally within some environments as part of the rock weathering process but is exacerbated by largescale earth disturbances characteristic of mining and other large construction activities, usually within rocks. As a result, the water becomes very acidic and damages downstream aquatic ecosystems. The ratedetermining step in the oxidation of iron pyrite and the formation of acidity in streams associated with coal and copper mines is the oxidation of ferrous iron. The acidic water formed by this process can dissolve many metals in. Nov, 2019 in a nutshell, acid mine drainage is a form of water pollution that happens when rain, runoff, or streams come in contact with rock that is rich in sulfur. Amd or acid rock drainage ard, collectively called acid drainage ad, is acidic water ph less than 5. A bench scale evaluation of organic substrates for use in constructed wetlands for the treatment of acid mine drainage 1991 197432284.
The effects of this phenomenon are so immense that it can cause devastation that could last for hundreds to thousands of years. Acid mine water drainage debating a sustainable solution. Sulfuric acid is produced when water interacts with sulfurbearing materials in the presence of oxygen and common bacteria1. A northeast acid mine drainage amd treatment facility was using calcium hydroxide lime to.
In colorado alone there are over 30,000 abandoned mines. In the eastern united states alone, amd from coal mines has adversely impacted fisheries associated with over,000 kilometers 8,000 miles of streams in pennsylvania, west virginia, ohio, and maryland. If constructed correctly, olcs should be maintenance free and provide amd. Acid mine drainage stock photos download 2 royalty free. Effects of acid mine drainage on the release of aluminum from.
Handbook of technologies for avoidance and remediation of acid mine drainage. However, bioelectrochemical system bes is a promising technology to simultaneously remove and recover metal ions from amd. Currently, most strategies for amd treatment merely focus on metal removal rather than metal recovery. Heavy metals emanating from former mine sites are a major threat to water resources. Acid mine drainage amd forms when sulfide m inerals are exposed to oxidizing conditions in coal and metal mining, highway construction, and other largescale excavations. Acid mine drainage an overview sciencedirect topics.
Springer nature is making sarscov2 and covid19 research free. The acid mine drainage may also contain high amounts of co2 which forms carbonic acid and further depresses the ph. The microbiology of acid mine drainage by jim taylor, p. Scribd is the worlds largest social reading and publishing site. Amd comes mainly from abandoned coal mines and currently active mining. Acid mine drainage amd occurs primarily when the mineral ore pyrite fes 2 is exposed to water and oxygen from air, producing soluble iron and sulfuric acid. Coal mine drainage prediction and pollution prevention in pennsylvania. Treatment of acid mine lakes tu bergakademie freiberg.
This is a natural chemical reaction which can proceed when minerals are exposed to air and water. In many cases, chemical consumption is the number one operating cost of an acid mine drainage treatment system. Acid mine drainage results when surface and ground water combine with sulfuric rock from the mines, causing a sulfuric acid. The term mineimpacted water is used because it is more inclusive than terms such as acid mine drainage amd or acid rock. In pennsylvania, reported aluminum concentrations in discharge samples from 140 abandoned coal mines showed that over. Effective pollution abatement necessitates control ling this reaction. Acid mine drainage treatment westech engineering, inc. The formation of acid mine drainage and the contaminants associated with it have been described as the largest environmental problem facing the u. When mine and mine waste drainage have neutral ph, with a high concentration of dissolved metals, they are called neutral or alkaline mine drainage lottermoser, 2010. Acid mine drainage amd forms when sulfide minerals are exposed to oxidizing. In examining this table, it is important to note that diffusion of oxygen into water is slow and, therefore, oxidation of iron sulfide is inhibited until the water level drops, which can occur periodically or seasonally in some cases. New logics v sep has the ability to perform membrane separations not possible using conventional membrane systems.
Wastewater treatment systems that are compact, economical, and reliable are now possible for the mining industry. Acid mine drainage amd is typically characterized by low ph and high dissolved iron. Pdf acid mine drainage amd occurs after mining exposes metal sulfides to. Acid mine drainage in south africa development actors. Illustrated with dozens of photographs, charts, tables and maps, the book is a compendium of 36 scientific papers written by various experts that cover these complex topics. As with all acid mine drainage sites, the rocks will remain capable of generating sulfuric acid for an unknown number of years, perhaps throughout the entire future human habitation of the region. As such, it is critical that chemical usage be optimized. The high acidity of acid mine drainage and the high amounts of dissolved heavy metals such as copper and zinc generally make acid mine drainage extremely toxic to most organisms pentreath, 1994. The acidic water formed by this process can dissolve many metals in bioavailable.
This acid leaches out metals in the rock, which can enter nearby. Acid rock drainage and acid mine drainage acid rock drainage ard is a natural process in which sulfuric acid is produced when sulfides in rocksfor example, pyrite fes 2 are exposed to air and water. The ochre orange precipitate may be formed as the stream enters the sea, or that formed in the stream may be washed in to the sea e. The objective of this phd research was to investigate the leaching of acid clays with acid minerock drainages amdard typically found in u. What can be done to prevent or clean up acid mine drainage. Acid mine drainage is known as one of the most severe threats to water brought about by mining.
The problem and the cleanup acid mine drainage is a global problem. Current methods for the remediation of acid mine drainage. Acid mine drainage overview acid rock drainage ard is produced by the oxidation of sulfide minerals, chiefly iron pyrite or iron disulfide fes2. In alaska acid mine drainage is a problem at a number of active alaskan metal mines including red dog, greens creek, and kensington mine. January 1996 acid mine drainage is a common problem in many parts of the country, originating from hardrock mines, strip mines or tailing piles. Acid mine drainage amd is a problem occurring across the globe, including in southeastern ohio. Acid mine drainage article about acid mine drainage by. Acid mine drainage prediction compares acid rock drainage factors of waste rock piles and tailings impoundments. This occurs along outcrops or scree slopes where sulfidebearing rock is naturally weathered.
Acid minerock drainage center for water, earth science and. Of note for future mine development, 90% of the mines that predicted low acid mine drainage potential had acid mine drainage problems at the time of the study. Ard is often mislabelled amd or acid mine drainage too. This is a natural chemical reaction which can proceed. Acid mine drainage research acid mine drainage amd has been the subject of intensive research since the 1960s. Acid mine drainage effects, types, plants, marine, oxygen. The objective of this phd research was to investigate the leaching of acid clays with acid mine rock drainages amdard typically found in u. Characterization of mine waste and acid mine drainage.
Following mine closure, the free water surface in the impoundment may be drawn down substantially, favoring amd conditions. Acid mine drainage prevention and control options nural kuyucak golder associates ltd. Typically, with acid mine water, there is a high amount of co 2 in the waste stream. This may be the biggest challenge of all the unknown. An overview and sustainability boat of knowledge ohio university. When the rocks made of sulfur are excavated from a mine surface or an underground mine, they react with water and oxygen to form sulfuric acid. Research efforts have proceeded recently through the acid drainage technology initiative. The second point was not earned as no correct description of a second environmental problem is present. This springerbrief focuses on acid mine drainage amd in the three basins in the. Sulfatereducing bacteria srb present a natural way to reverse the damage caused by acid mine drainage. Acid mine drainage mines built as early as the 1800s were developed in a manner which utilized gravity drainage, to avoid excessive water accumulation in the mines as a result, water polluted by acid, iron, sulfur and aluminum drained away from the mines and into streams results of acid mine drainage. Acid mine drainage will ultimately be neutralised by the sea, unless it is already neutralised.
Acid mine drainage amd is a typical source of environmental pollution ascribing to its characteristics of high acidity and heavy metal content. Water flowing through active or abandoned mine sites can become polluted by the material being mined1. Amd is caused when water flows over or through sulfurbearing materials forming solutions of net acidity. The use of sulphidefree tailings in instrumentation to monitor. Thus, this study applied some simple testing methods to the. Acid mine drainage amd is a problem occurring across the. Although acid mine drainage is the most common impact of mining on water quality, the variety of mineral geology is such that there is no singlecharacteristic mine water. Acid minerock drainage center for water, earth science. Acid mine drainage is a condition where, as the name suggests, the water is made acidic.
Usps acid mine drainage program is a successful, cost effective solution turnkey program reduced chemical expenses, solids, and energy costs. This springerbrief focuses on acid mine drainage amd in the three basins in the witwatersrand, south africa. Acid mine water drainage debating a sustainable solution to a. By far the most common mine drainage problem is that of acid mine drainage amd. Skaff mineral sciences laboratories 555 booth street ottawa, ontario k1a 0g1 july 1991 funded by. In a nutshell, acid mine drainage is a form of water pollution that happens when rain, runoff, or streams come in contact with rock that is rich in sulfur. Although hightech analytical methods have been highlighted for mineral characterization and quantification, simple testing methods are still practical ways to perform in a field laboratory in mines. Description of the buffering capacity of the original acid mine lake water 90. Media in category acid mine drainage the following 51 files are in this category, out of 51 total. A mines drainage substances such as acid can destroy streams, rivers and aquatic life.
Major environmental incidents caused by acid mine drainage. Drainage flowing from or caused by mining that is typically highly acidic with elevated metal levels increased concentrations of cadmium, nickel, lead. Prediction of water quality at surface mine sites pdf format acid mine drainage abatement projects. When water flows over or through sulfurbearing mine tailings, a chemical reaction occurs between the water and rocks resulting in metalrich water. Illustrated with dozens of photographs, charts, tables and maps, the book is a compendium of 36 scientific papers written by. The sulfuric acid causes leaching of iron, manganese, lead, copper, zinc and cadmium from the rock it interacts with. Acid mine drainage article about acid mine drainage by the. Effective treatment options for acid mine drainage in the. Acid mine drainage amd occurs when metal sulfides, most commonly pyrite, are exposed to and react with air and water. So, to better understand amd and ard, lets begin by defining some terms like ph the standard measure of acidity. Acid mine drainage, rock drainage, and acid sulfate soils. Acid mine drainage amd is currently the main pollutant of surface water in the midatlantic region. The first step in the acid mine drainage flowsheet is decarbonation. The burning of fossil fuels is a global environmental problem, not a specific environmental problem at mine sites.
May 17, 2016 the first step in the acid mine drainage flowsheet is decarbonation. Define acidmine drainage constructed wetlands as passive treatment systems acidtolerant aquatic plants benhar ironstone mine spoil in central scotland. One reason that pyrite is important in amd generation is that it forms under a variety of conditions and is widespread in different rock types. A mine s drainage substances such as acid can destroy streams, rivers and aquatic life. Jul 11, 20 process of acid mine drainage geochemical and microbial reactions during weathering of sulfide minerals pyrite in coal, refuse, or mine overburden oxidation of sulfide minerals in the presence of air, water, and bacteria formation of sulfuric acid and increase in acidity solubilization of metals due to low ph 5. Pure neutral water has a ph of 7, acids have a ph less than 7 and. It provides a background to amd and its impactsfrom a social science perspective. Characterization of mine waste rocks and prediction of acid mine drainage amd play an important role in preventing amd. Many streams derived from acid mine drainage are largely devoid of life for a. The term mineimpacted water is used because it is more inclusive than terms such as acid mine drainage amd or acid rock drainage ard.
Apr 05, 2018 acid mine drainage is known as one of the most severe threats to water brought about by mining. Acid mine drainage prevention and control options imwa. Acidic water is not the only issue caused by acid mine drainage. Acid mine drainage amd forms when sulfide minerals, particularly pyrite and marcasite, have been exposed to oxidizing conditions during mining and other excavation activities, such as highway. The primary cause of environmental damage from abandoned hardrock mine sites is acid mine drainage, which carries dissolved heavy metals and arsenic into surface water, soil and groundwater. There are four chemical reactions that represent the chemistry of pyrite weathering to. When the rocks made of sulfur are excavated from a mine surface or an underground mine, they. Effects of acid mine drainage on the release of aluminum. In some regions, it is the most common form of stream and river pollution.
The ph scale actually measures hydrogen ion concentration in water solutions. Download 2 acid mine drainage stock photos for free or amazingly low rates. Acid mine drainage solutions for the mineral industry. The south african government and nongovernmental organizations response to amd is assessed, as well the socioeconomic and developmental effects of amd. There are four chemical reactions that represent the chemistry of pyrite weathering to form acid mine drainage. Acid mine drainage stock photos download 2 royalty. Pdf acid mine drainage control and treatment researchgate. Acid rock drainage as a concern and part of all metals and mining operations. Treating acid mine drainage from abandoned mines in remote.
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