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Sediments and Sedimentary Rocks
Published in Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough, Earth Materials, 2019
Dexter Perkins, Kevin R. Henke, Adam C. Simon, Lance D. Yarbrough
Waters of both the Mediterranean Sea and the Gulf of Mexico have deposited thick layers of evaporite minerals in the past when they became isolated from the larger oceans and evaporation led to oversaturation. In both places, when ocean water evaporated, precipitation started with minerals that were least soluble in water and progressed to those that were most soluble. So, initial precipitates were calcite (CaCO3) and other carbonates. Subsequently, gypsum (a sulfate) and halite (a chloride) were deposited—and then more sulfates and chlorides, including anhydrite, sylvite, carnallite, langbeinite, polyhalite, and kainite. Massive layers of all these minerals underlie both the Mediterranean and the Gulf of Mexico today.
Environmental mitigation and pollution control technologies
Published in Anjan Kumar Chatterjee, Cement Production Technology, 2018
The calcium sulfate passes down the kiln and, as the temperature rises to 1400°C and above, it decomposes again, following the reverse path of Equation 9.1. The SO2 is carried back to the kiln inlet and reacts again with calcium and alkalis in the raw meal to form calcium sulfate, alkali sulfate, or even complex compounds like calcium langbeinite (K2SO4.2CaSO4). These compounds eventually become incorporated in clinker and are carried out of the kiln. It shows that, although there could be substantial circulation of sulfur compounds within the kiln, practically all the gaseous SO2 leaving the kiln will be arrested by the bottom preheater cyclone and returned to the kiln.
Potash And Other Salts
Published in Earle A. Ripley, E. Robert Redmann, Adèle A. Crowder, Tara C. Ariano, Catherine A. Corrigan, Robert J. Farmer, L. Moira Jackson, Environmental Effects of Mining, 2018
A. Ripley Earle, Robert E. Redmann, Adèle A. Crowder, Tara C. Ariano, Catherine A. Corrigan, Robert J. Farmer, Earle A. Ripley, E. Robert Redmann, Adèle A. Crowder, Tara C. Ariano, Catherine A. Corrigan, Robert J. Farmer, L. Moira Jackson
The term “potash” refers to the oxide and carbonate compounds of potassium that were, at one time, produced from wood ashes. The main commercial potassium minerals are sylvite, carnallite, kainite, and langbeinite, with sylvite accounting for the majority of the ore. Potash production is still often expressed in terms of the potassium oxide (K2O) equivalent, although potassium chloride (KCl) is the actual chemical form of the mineral sylvite. This book uses only weights of KCl, which can be converted to K2O equivalents by multiplying by 0.63.
Detecting mining-induced ground deformation and associated hazards using spaceborne InSAR techniques
Published in Geomatics, Natural Hazards and Risk, 2018
Albert Zhang, Jason Lu, Jin-Woo Kim
Under the barren desert of the Delaware Basin southeast of Carlsbad, New Mexico, large deposits of valuable mineral assets reside beneath layers of anhydrite, halite, sylvite, and other evaporite minerals (Barker and Austin 1993). As such, in the last few decades, the region has become a centre for mining activities, particularly for the extraction of potassium salts, including muriate of potash (KCl) and langbeinite (K2Mg2(SO4)3) (Barker et al. 1996). Used primarily in the production of plant fertilizers, potassium salts are primarily extracted in the Carlsbad potash mines using conventional room-and-pillar mining techniques, in which continuous boring machines grind underground deposits into small chunks, which are then transported to potash mills on the surface (Austin 1980). There, the ore is ground into powder, crystallized, and processed into commercially usable forms, such as fertilizer (Austin 1980).