Acid mine drainage chemistry pdf

Acid mine drainage amd, a waste from mining sites is highly acidic, rich source of sulfate and heavy metals. Mineralogical transformations controlling acid mine. Case study of acid mine drainage amd and remediation. We also acknowledge previous national science foundation support under grant numbers 1246120, 1525057. Acid mine drainage amd is generated under environmental conditions when sulfide minerals are exposed to oxygen, water, and acidophilic microorganisms. The mining of coal deposits and metal ores often results in a phenomenon called acid mine drainage amd. Mines should be able to use human rights rhetoric and additional contextual analysis to better understand how social impact issues can evolve into potential human rights violations. Acid mine drainage amd, which is caused by the biological oxidation of sulfidic materials, frequently contains arsenic in the form of arsenite, asiii, andor arsenate, asv, along with much higher concentrations of dissolved iron. The chemistry of oxidation of pyrites, the production of. 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. In some regions, it is the most common form of stream and river pollution.

Mine drainage is formed when pyrite an iron sulfide is exposed and reacts with air and water to form sulfuric acid and dissolved iron. 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. Mine drainage chemistry reduce the impacts and engineering costs of poor quality mine drainage, such as acid mine drainage, through a comprehensive understanding of your site chemistry managing drainage water quality is a critical concern for all mining and nonmining rock handling operations. The microbiology of acid mine drainage by jim taylor, p. Environmental impact and remediation of acid mine drainage. These metrics are regularly updated to reflect usage leading up to the last few days. Arsenic geochemistry of acid mine drainage springerlink. Acidmine drainage abatement project in clarion county a report by andrew m. As a result, the water becomes very acidic and damages downstream aquatic ecosystems. Acid mine drainage solutions for the mineral industry. Acid drainage from an abandoned coal mine has impacted this southwestern virginia stream. 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. The rate and degree by which acid mine drainage proceeds can be increased by the action of certain bacteria. Removal of arsenic from synthetic acid mine drainage by.

Supergene alteration of the sulphide ore and the mine waste leads to the formation of efflorescence and generation of acid mine drainage amd filling the pitlakes. Inap is an organization of international mining companies dedicated to reducing liabilities associated with sulphide mine materials. There is actually a complex series of reactions and side reactions, but the net equation is often written according to equation 1. Sources of nonpoint source pollution acid mine drainage amd is currently the main pollutant of surface water in the midatlantic region. There are four chemical reactions that represent the chemistry of pyrite weathering to form acid mine drainage. Acid mine drainage amd is typically characterized by low ph and high dissolved iron. Western pennsylvania was once a great coal mining region.

This is a natural chemical reaction which can proceed when minerals are exposed to air and water. Characterization of mine waste rocks and prediction of acid mine drainage amd play an important role in preventing amd. Pdf biogeochemistry of acid mine drainage and a method. Citations are the number of other articles citing this article, calculated by crossref and updated daily. The chemistry is complex and not completely identified. Treating acid mine drainage from abandoned mines in remote areas john j. Inap exists to fill the need for an international body which mobilizes acid drainage. Acid mine drainage environmental notes on mining, updated september 2009 pyrite fes2 is commonly associated with coal and metal ore deposits.

January 1996 acid mine drainage is a common problem in many parts of the country, originating from hardrock mines, strip mines or tailing piles. Mine acid drainage mad is the runoff produced when water comes into contact with exposed rocks containing sulfurbearing minerals that react with water and air to form sulfuric acid, dissolved fe and al, and other chemical elements blowes et al. This laboratory project uses the context of acid mine drainage to teach concepts important to analytical chemistry and quantitative analysis. Acid mine drainage amd is a problem occurring across the. Steve oravetz program leader usda forest service technology and development program missoula, montana 7e72g71 acid mine drainage study october 1998 united states department of. The chemicals allow copper minerals to rise to the top and stick to. 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. Acid mine drainage an overview sciencedirect topics. An introduction to acid mine drainage wv department of. Acid mine drainage is a major driving force responsi.

Generation of asrich acid mine drainage, natural attenuation processes and solutions for passive in situ remediation. This results primarily from the oxidative breakdown of transition metal sulfides, especially pyrite fes 2. Because the chemistry of water samples can rapidly change if removed from the mine, many mine drainage measurements are made in the field. Department of the interior colorado school of mines u. Acid mine drainage boat of knowledge ohio university.

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 mine drainage overview acid rock drainage ard is produced by the oxidation of sulfide minerals, chiefly iron pyrite or iron disulfide fes2. Pdf a bacterium, thiobacillus ferrooxidans, is of prime importance in the formation of acid drainage from pyritic material. Ard is often mislabelled amd or acid mine drainage too. A study of environmental assessment of acid mine drainage in ngwenya, swaziland 21 this acidic effluent produced during the mining process is called acid mine drainage amd 5,6. Wildeman billings symposium asmr annual meeting assessing the toxicity potential of mine waste piles workshop june 1, 2003 u. Amd comes mainly from abandoned coal mines and currently active mining. Biogeo chemistry of acid mine drainage and a method to control.

When the acid forming minerals do not contain significant quantities of iron, the acidic waters do. The acid mine drainage may also contain high amounts of co2 which forms carbonic acid and further depresses the ph. Paul ziemkiewicz, director, wv water research institute. These frame the predicted metal criterion sum ccus 1, showing mean and range of. Chemistry a cidic drainage is a natural process that becomes accelerated and. Characterization of mine waste and acid mine drainage. Acid mine drainage research acid mine drainage amd has been the subject of intensive research since the 1960s. Hardness is the concentration of divalent cations e. The controlling parameters are defined by the physics of the site. Acid mine drainage prevention and control options 601 prediction of performance the performance of the designed or selected options compared to the adopted standards is predicted by applying appropriate engineering techniques e. Handson experiments to test for acid mine drainage dr. Research efforts have proceeded recently through the acid drainage technology initiative. Acid mine drainage the center for rural pennsylvania.

So, to better understand amd and ard, lets begin by defining some terms like ph the standard measure of acidity. Acid mine drainage amd is a major environmental hazard of 20th century mining practice. A study of environmental assessment of acid mine drainage. It affects aquatic ecosystems by a number of direct and indirect pathways. Aqueous chemistry, coupled with discharge volume can, thus, estimate the annual production of tree, amd sludge and the grade of amd sludge as a process feedstock. 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. The orange coloration is due to the iron fe that has been mobilized by the sulfur oxidation process, which causes acid mine drainage to occur. However, acid mine drainage eventually leaves its mark. Major impact areas are rivers, lakes, estuaries and coastal waters, although amd affects different aquatic ecosystems in different ways. Pdf acid mine drainage treatment with chemicals jeff. Progression of community reassembly responses with acid mine drainage recovery. The acid runoff further dissolves heavy metals such as copper, lead, and mercury into groundwater or. Most discussions on acid mine drainage refer to the physical process of oxidation while the role of microorganisms is left unnoticed. The remnants of this industry are still with us in the form of abandoned mines that underlay a great portion of the land on which we live, and in the drainage of acidic waters from the mines into our streams and rivers.

The international network for acid prevention inap is an industry group created to help meet the challenge of acid drainage. Mcsurdy department of energy pittsburgh research center p. Recovery of rare earth elements rees from coal mine drainage dr. Some australian work using 18 o in near isotopically pure o 2 and h 2 o has identified the general direction of the reaction path. Mining, waste ore burden, tailings, and exposure of abandoned mines to the environment promote amd. Article views are the countercompliant sum of full text article downloads since november 2008 both pdf and html across all institutions and individuals. Sulphate concentrations range from 4,600 to 4,850 mgl and from 35,900 to 38,500 mgl for the mathiatis and sha mines, respectively. 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.

Proc, difpolmine conf, le corum, montpellier, france, pp 17 evangelou vp 1998 pyrite chemistry. Recovery of rare earth elements rees from coal mine. Its oxidation occurs spontaneously in nature, causing environmental problems like acid mine drainage amd and mine. The life cycle of acid mine drainage copper ore from arizona concentrating ground up rock is mixed with water, air bubbles and small amounts of chemicals. Amd is a major pollutant resulting in enhanced acidity of water bodies wherever it exists 7. Chemical extractions, xray diffraction xrd, scanning 40 electron microscopy sem, and fourier transform infrared spectroscopy ftir were. Fundamentals of minedrainage formation and chemistry kathleen s. Some or all of this iron can precipitate to form the red, orange, or yellow sediments in the bottom of streams containing mine drainage. Conventional technologies for treatment of amd include various physicochemical methods, which involve excessive use of chemicals and capital. The first measurement typically looks at acidity, which is. Work carried out at the abandoned copper cu and sulphur s mine at avoca south east ireland has shown acid mine drainage amd to be a multifactor pollutant. 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. The term mine impacted water is used because it is more inclusive than terms such as acid mine drainage amd or acid rock drainage. Acid rock drainage as a concern and part of all metals and mining operations.

9 888 432 1399 1273 1135 726 544 206 1557 46 1534 529 560 37 1033 1520 458 584 568 297 1343 685 568 804 1080 1430 344 9 565 937 1054 173 823 696 192 1343 885 1047