Two grams of each material (gypsum or calcite) was equilibrated with 20 mL of the soil water extract. The suspensions were shaken at 30 rpm for 16 h at room temperature, centrifuged (Beckman, 9,630× g ), and then, the supernatants were filtered (0.45 µm) and stored at 4 °C until the analyses.
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Abstract and Figures. The methods for gypsum content determination in soils are summarized and their applicability discussed. Special attention is given to the critical …
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It can be observed that in all impact indicators except mineral extraction, natural gypsum generated a greater impact compared to recycled gypsum options. This difference reached its highest value in the category of ionizing radiation, where there was an 87.82% increase with respect to gypsum from plasterboard waste. In addition, it is ...
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A Montana university professor is set to conduct the most comprehensive study yet of the Hideaway Hills mine collapse in order to determine if other homes are at risk. "This is the first ...
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In this paper we report the maximum potential for cement substitution with secondary materials to reduce CO2 emissions globally (1.3 Gt CO2-eq. in 2018) and on a country-by-country basis.
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Gypsum occurs in extensive beds associated with other evaporite minerals (e.g., anhydrite and halite), particularly in Permian and Triassic sedimentary formations; it is deposited from ocean brine, followed by anhydrite and …
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As a consequence, gypsum typically occurs as layers associated with limestone, dolostone, shale, and rock salt. As seawater evaporates, gypsum is the first 'salt' to be precipitated, followed by anhydrite, halite, and finally sylvite. Usually found with other evaporite and carbonate minerals, such as anhydrite, calcite, dolomite, borax, and ...
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The Gypsum Association (GA) and its members engaged the Athena Sustainable Materials Institute to conduct a representative, transparent and ISO 14040/44:2006 compliant cradle-to-common gypsum wallboard products – ½" (12.7 mm) Regular and 5/8" (15.9 mm) Type X gypsum wallboard – as produced in the United States in 2010.
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The gypsum comes at the forefront of these products in terms of availability of raw material and low manufacturing costs, where Sudan's stockpile of gypsum is estimated at 300 million tons. This ...
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Contribute to legaojm/m development by creating an account on GitHub.
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Dr. Sara Palacio, José Azorín, Gabriel Montserrat & Dr. Juan Pedro Ferrio Some minerals hold water in their crystalline structure. Such is the case of gypsum (CaSO4 2H 2 O), a rock-forming mineral present in five continents that is particularly prevalent in the arid and semi-arid regions of Africa and Western and Central Asia 1.Crystallization water …
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Gypsum Crystal, unknown Locality. University of Waterloo Earth Sciences Museum Collection. Gypsum can be found as thick layers in shale and as attractive crystals. Rock Gypsum - soft, granular, white to gray, with 30 …
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The ground gypsum exits the mill in a gas stream and is collected in a product cyclone. Ore is sometimes dried in the roller mill by heating the gas stream, so that drying and …
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extraction, 19 % (1.5 Gt) from imports and 8 % (0.7 Gt) from recy-cling (see also recycling-related Indicator 16) and backfilling (0.06 Gt). More information can be found in Indicator 3 on import reliance. Of the 8 Gt of materials that are processed in the EU economy, 39 % (3.1 Gt) are used for energy, 53 % (4.3 Gt…
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>60 times: The secretion of Ca sulfates (gypsum and anhydrite) can take place from solutions of small concentration at temperatures much higher than 30°C. Gypsum, for example, is excreted at a temperature of 58°C from the water with normal salinity, and anhydrite secretes much above that temperature. ... The extract of gypsum or anhydrite ...
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This study includes natural hazards and environmental problems caused by gypsum on and near the soil, water, and structures. These are karst-specific deformations (caves, fractures, cracks) naturally occurring in gypsum areas, and the problems of salinization, corrosion, erosion, soil and water pollution that occur as a result of …
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USE OF GYPSUM TO ENHANCE ROOTING AND WATER EXTRACTION IN … Project Methods Ultisol soil profiles will be constructed inside 7.6-cm PVC pipe containers, simulating a shallow `A' horizon, 5-10 cm deep over a clayey, acidic Bt. Gypsum will be incorporated into the top 2 cm of the topsoil at variable rates, and turfgrass sprigs planted.
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1:5 soil-water extraction 7.0 Values must be corrected to correlate with saturated paste Ammonium Acetate 7.0 Most commonly used extraction method, but should not be used on calcareous or gypsiferous soils Ammonium Chloride 5.5 Not commonly used due to extra steps that account for the dissolution of calcium carbonate
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Gypsum forms the basis for some of the well-known brands of toothpaste, and, thereby helps to pay the salary of some of television's best-known en-tertainers. Most of the fixtures in bathrooms are made of clay formed in a mold of gypsum plaster and chances are that gypsum board is behind the wall tile. Gypsum Molds . . .
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materials extraction (e.g. gypsum quarrying) through product manufacturing, including related transportation. We have also provided estimates of typical or average transportation modes and distances for the distribution of finished products from relevant manufacturing facilities to the six
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Here we report the mechanism by which gypsum rocks from the Atacama Desert, Chile, provide water for its colonizing microorganisms. We show that the microorganisms can extract water of crystallization (i.e., structurally ordered) from the rock, inducing a phase transformation from gypsum (CaSO 4 ·2H 2 O) to anhydrite (CaSO 4 ).
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There are three main types of byproduct gypsum that are produced by industrial activities: titanium gypsum (TG), which is produced by neutralizing acidic liquid …
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Abstract. There has been an increasing demand on the REE supply in the last few decades and special attention has been directed towards the extraction process of these elements. The impurity removal step is a key step in the processing circuit as it can determine the purity of the final product. Lime neutralization is deemed a preferred …
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Agricultural gypsum is used to offset alkali and to restore impervious, dispersed soils that have been deflocculated by overdoses of ammonia-rich fertilizers or …
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To investigate and validate the water extraction and phase transformation mechanisms found in the natural geological environment, we cultivated a cyanobacterium isolate on gypsum rock samples under …
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The gypsum reduction is carried out in any suitable reactor, although a fluidized bed reactor is preferred with a circulating fluidized bed reactor being most preferred. Gaseous by-products from the gypsum reduction may be incinerated and the heat values used to heat the reducing mixture prior to its use in reducing the calcium …
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gypsum was 18.0 million tons. Synthetic gypsum is mainly produced as a byproduct in flue gas desulfurization (FGD) systems. Calcined gypsum is produced domestically from crude gypsum by heating selenite. In the United States, gypsum is primarily used to manufacture wallboard and plaster for homes, offices, and commercial buildings.
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Gypsum is a mineral found in crystal as well as masses called gypsum rock. It is a very soft mineral and it can form very pretty, and sometimes extremely large colored crystals. Massive gypsum rock forms within layers of sedimentary rock, typically found in thick beds or layers. It forms in lagoons where ocean waters high in calcium and sulfate ...
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Phosphogypsum (PG) is a solid waste product generated during wet-process phosphoric acid production. Various impurities considerably reduce the purity, …
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Concrete is formed when portland cement creates a paste with water that binds with sand and rock to harden. Cement is manufactured through a closely controlled chemical combination of calcium, silicon, aluminum, iron and other ingredients. Common materials used to manufacture cement include limestone, shells, and chalk or marl combined with ...
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Contribute to changjiangsx/sbm development by creating an account on GitHub.
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Particle size distribution of the monazite concentrate used in the experiments (x10 = 14.80 μm, x50 = 57.55 μm, and x90 = 120.47 μm). …
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Contribute to naicha22/2022 development by creating an account on GitHub.
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The transitions between the various phases of geologic calcium sulfate minerals—gypsum, bassanite, and anhydrite—has been studied (15, 18–20).It is known that gypsum may lose some or all of its structural or "crystalline" water and subsequently transforms to either a hemihydrite phase, bassanite (CaSO 4 ·1/2H 2 O), or an …
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There are five basic stages in gypsum processing: Excavation is sometimes carried out by digging out an area of ground where the gypsum is located using open-cast techniques. …
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CertainTeed Corporation Professional: 800.223.8990 P.O. Box 860 Consumer: 800.782.8777 Valley Forge, PA 19482 Online: Page 2 of 2 | …
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