Carbon dioxide (CO 2), another emission resulting from burning coal, is a major greenhouse gas that is associated with global warming (see Chapter 13 ). Burning of coal is classified as incomplete combustion, since the reaction of carbon (in coal) with oxygen produces carbon monoxide and/or carbon (soot) in addition to carbon dioxide.Web
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AMD: a global concern. Acid mine drainage refers to water discharged from active, inactive, or abandoned mine and reclaimed areas with relatively higher total acidity compared with total alkalinity. It encompasses several chemical, biological, and electrochemical reactions, which the paper discusses in later sections.Web
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known that coal spontaneous combustion is a major hazard in the mining industry, and serious coal spontaneous combustion can burn mining machines and even cause major safety accidents.4−7 The essence of coal spontaneous combustion is chemical reactions. Therefore, it is necessary to conduct scientific research based on the inherent ...Web
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Abstract. Acid mine drainage (AMD), a waste from mining sites is highly acidic, rich source of sulfate and heavy metals. Conventional technologies for treatment of AMD include various physicochemical methods, which involve excessive use of chemicals and capital. Biological treatment has emerged as efficient, cost-effective, and eco-friendly ...Web
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Residual coal in mine goafs will be oxidized in the presence of air leakage, which can be well tracked through the radical reaction. This study aimed to explore the changes in radical parameters and the reactivity and persistence of newly produced radicals of coal at different temperature stages. To this end, an in situ electron spin resonance …Web
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One of the most prominent impacts from legacy coal mining comes from acid mine drainage (AMD) discharges, formed through the chemical reaction of subsurface water entering coal beds that contain sulfur …Web
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In order to cut off the chain reaction in the process of coal oxidation at low temperature (COLT), butylated hydroxytoluene (BHT) was used as an inhibitor to explore its inhibition effect and mechanism. In this paper, in situ Fourier transform infrared spectroscopy, electron paramagnetic resonance, and gas production of COLT …Web
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In 2020, methane emissions from coal mining and abandoned coal mines accounted for about 7% of total U.S. methane emissions and about 1% of total U.S. greenhouse gas …Web
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Mine drainage forms from a chemical reaction between water and rocks containing sulfur-bearing minerals. The resulting waters become rich in sulfuric acid and dissolved iron. As the iron settles out of …Web
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Show abstract. ... 10 One major cause of water contamination is the generation of acid from the oxidation of sulphurbearing minerals like pyrite in coal mines. 11, 12 Acid mine drainage (AMD ...Web
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This test involves chemical reactions between coal and coal-shale and oxygen (Onifade et al. 2018a). A new index, referred to as the Wits-CT Index was developed (Onifade et al. 2018a). The liability of different samples to self-heat is evaluated for 24 h under the influence of oxygen. ... Symposium on safety in coal mines, CSIR, Pretoria, …Web
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All fossil fuels are made up of mostly carbon and hydrogen. When burned, the carbon is converted to carbon dioxide and the hydrogen to water. Each of those reactions produces a slightly different ...Web
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Coal is a combustible black or brownish-black sedimentary rock with a high amount of carbon and hydrocarbons. Coal is classified into four main types, or ranks depending on the types and amounts of carbon present and on the amount of heat energy the coal can produce, including anthracite, bituminous, subbituminous, and lignite (highest to ...Web
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A study of fire propagation in coal seam with numerical simulation of heat transfer and chemical reaction rate in mining field September 2019 International Journal of Mining Science and …Web
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Owing to the existence of As in different oxidation states, As may participate in numerous chemical reactions and give rise to different products. Thereby, the health impact of As heavily depends on its chemical form. Coal combustion and smelting are the main two sources of As (Akter KF 2005). Coal trace metals mainly depend on the coal …Web
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The chemical and physical processes that cause self-heating include the oxidation of coal and other carbonaceous material, sorption of moisture by the material, and mineral reactions. These processes are complex and are affected by many factors, both internal (i.e. properties of the material itself) and external (i.e. ambient conditions ...Web
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The chemical reaction forms sulfuric acid and dissolved iron, some or all of which can separate to form the rust-colored sediments that become visible on the …Web
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The accurate prediction of coal spontaneous combustion (CSC) in the goaf areas of coal mines is a vital aspect of the migration from passive to active fire prevention and control. However, CSC is highly complicated and …Web
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The coal-oxygen complex reaction also corresponds to periods of variation in reaction rates for most chemical reactions, which fit the Gaussian distribution. So the Gaussian formula can be used to fit the sub-peaks in the whole stage of DTG curve to distinguish different reaction mechanisms (Deng et al. 2017 ; Li et al. 2019b ).Web
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Acid mine drainage mostly occurs where mining is done to extract coal or metals from sulfur-bearing rocks. Silver, gold, copper, zinc, and lead are commonly found in association with metal ...Web
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Alkaline chemicals are commonly added to discharges from coal mines to increase pH and decrease concentrations of acidity and dissolved aluminum, iron, manganese, and associated metals. The annual ...Web
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1. Introduction. The occurrence of spontaneous combustion is one of the major challenges faced by the South African coal mining sector. The physical and chemical reactions between oxygen and external active structures of coal particles which releases heat are behind the event of spontaneous combustion.Web
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Coal consumption in metal smelting and processing, petroleum and coal processing and conversion, coal mining and washing, chemical raw materials and products and other industries accounted for 12.9%, 12.2%, 6.1%, 5.9% and 14.2%, respectively, of coal consumption. ... The kinetic mechanisms of low-rank coal …Web
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Coal fire is defined as "under natural conditions, once underground coal and air establish contact, a series of chemical reactions occur, which changes spontaneous combustion to severe combustion that has a certain …Web
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As an explosion control measure, rock dusting has been used in underground coal mines in many major coal producing countries with different standards. The effectiveness of the rock dust in reducing explosion intensity has been proven by historic events and laboratory experiments. The main functions of rock dust in controlling mine …Web
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Mine drainage is metal-rich water formed from a chemical reaction between water and rocks containing sulfur-bearing minerals. The resulting chemicals in the water are sulfuric acid and dissolved iron. ... Acidic, metal-laden drainage from abandoned coal mines can have substantial effects on aquatic resources. Problems that can be associated ...Web
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Coal is also an important source of light aromatic hydrocarbons for the chemical synthesis industry. If coal is heated the gases and residues produced can be used in manufacturing plastics, …Web
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One of the most prominent impacts from legacy coal mining comes from acid mine drainage (AMD) discharges, formed through the chemical reaction of subsurface water entering coal beds that contain sulfur-bearing minerals. This process results in the formation of sulfuric acid – particularly in flooded abandoned mines.Web
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