With the best calcination temperature of 800 °C, gypsum plaster showed a relatively quick setting and maximum strength with a compact microstructure and low hydration degree due to the large formation of Na 2 SO 4 and nucleation sites. Recycling PG to prepare anhydrite is recommended because of its excellent performance and …
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Two kinds of inorganic reinforcing materials, single Portland cement clinker, compound Portland cement clinker and mineral powder, were used to analyze the effects of desulfurized gypsum on the properties of desulfurized gypsum based cementation material. The results show that either single Portland cement clinker or compound …
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The preparation of natural and synthetic gypsum prior to calcination, such as drying and grinding. The various calcination methods for β-hemihydrate and α-hemihydrate are reviewed, such as batch kettle, continuous kettle, submerged combustion kettle, conical kettle, and other calcination equipment.
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The invention discloses a novel calcination-free desulfurized gypsum brick, belonging to the production field of building bricks. The calcination-free desulfurized gypsum brick comprises the following components in parts by weight: 45-55 parts of desulfurized gypsum, 25-35 parts of coal ash, 5-10 parts of No. 32.5 cement, 4-10 …
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The furnace temperature and the residence time are important for proper SO 2 sorption: Shemwell et al. (2000) Limestone injection into furnace and activation of unreacted calcium (LIFAC) ... (Oriza sativa L.) growth and yield using desulfurized gypsum in the west of Songnen Plain, northeast China Geoderma, 187–188 (2012), ...
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1. Calcination process of desulfurized gypsum (1) Low temperature and slow calcination. Low-temperature slow-speed calcination means that the material stays in …
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calcination temperature of β -hemihydrate gypsum is signicantly lower than that of cement, usually within a range of 135–180°C, and it can be fully recycled (Lushnikova and …
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The hammer mill, being a short-time calcining system, grinds, dries, calcines and classifies the raw gypsum in a single step. The resulting stucco is suitable for the production of plasterboard, gypsum fiberboard and gypsum wall blocks. A hammer mill can process moist FGD gypsum, pre-crushed natural gypsum, or a mixture of both.
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The high-temperature calcination method (equipment) is that the desulfurized gypsum is in direct contact with the high-temperature flue gas for heat exchange, rapid dehydration and calcination.
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Flue gas desulfurized gypsum (FGDG) is a waste material produced in the power stations during the flue gas desulfurization process. ... FGDG is also used to produce CaS O 4 ∙ 0.5 H 2 O or CaS O 4 by calcination method [10], [11]. ... Strength properties of geopolymers derived from original and desulfurized red mud cured at ambient …
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To determine which factor, the calcination temperature of FGD gypsum (500–800 °C), the hydration time (3–28 days) or the amount (0–2%) of the activators …
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The FGD gypsum was firstly calcined in the DRY-36 high-temperature industrial furnace at 800 C for 1 h, and then cooled to room temperature within the …
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The highest compressive strength was observed for gypsum waste treated at 180 °C for 24 h. Likewise, Rossetto et al., studied the mechanical strength and workability at a fixed calcination temperature of 150 °C for different time periods (1, 2, 3, 4, 5, and …
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The calcination temperature rises to 180 °C, 2 h flexural and compressive strength are respectively up to 2.6 and 4.3 MPa, conforming to the grade 2.0 …
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Automotive dyes and pigments. B. Kaur, S.N. Bhattacharya, in Handbook of Textile and Industrial Dyeing, 2011 7.4.1 Calcination. Calcination is a process of heating a substance under controlled temperature and in a controlled environment. This process is known to improve the chroma, tinctorial strength, pigmentary texture, weather stability, light …
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Flue gas desulfurized gypsum (FGD gypsum), mainly originates from thermal power plants, smelters, and large-scale enterprise boilers. This article reviews the production in China and the latest beneficial utilizations of FGD gypsum. China is a large coal-consuming country and has always had serious SO 2 emissions. Therefore, the …
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The calcination of FGD gypsum is used as a phosphate adsorption material to treat phosphate wastewater. Roasting improves the adsorption performance of FGD …
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The calcination temperature of kaolinitic clays was investigated to optimize the reactivity of calcined clay. Batches of a clay with 50% kaolinite were calcined in an oven at five different calcination temperatures from 600 to 850°C. ... An example is shown in Figure 8, where different gypsum additions (in addition to the amount in the cement ...
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The furnace temperature and the residence time are important for proper SO 2 sorption: Shemwell et al. (2000) Limestone injection into furnace and activation of unreacted calcium (LIFAC) ... (Oriza sativa L.) growth and yield using desulfurized gypsum in the west of Songnen Plain, northeast China. Geoderma, 187–188 (2012), …
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from Desulfurized Gypsum with High Chloride Ion Content To cite this article: Dongjie Yin et al 2020 IOP Conf. Ser.: Mater. Sci. ... and affect the calcination temperature and quality of
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Research related to traditional multiphase gypsum has mainly focused on the mineralogical and textural characterization of historic mortars and plasters [6], [10], [11], [12], [13].There is, however, a lack of systematic studies which correlate the properties of the set plaster (i.e., mechanical strength and weathering resistance) with the …
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The obtained semi-aqueous desulfurized gypsum was the original desulfurized gypsum, which was placed in an oven at 180 °C and dehydrated for 2 h under synchronous heating with the box. ... This phenomenon was caused by the effect of the calcination temperature on the phase change of desulfurized gypsum promoting …
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Flue gas desulfurization (FGD) gypsum mainly contains gypsum, which comes from the FGD by using lime or limestone. The effects of calcining temperature …
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DOI: 10.1016/j.jobe.2021.103511 Corpus ID: 239896906; Recycling of phosphogypsum to prepare gypsum plaster: Effect of calcination temperature @article{Cao2021RecyclingOP, title={Recycling of phosphogypsum to prepare gypsum plaster: Effect of calcination temperature}, author={Wenxiang Cao and Weili Yi and Jia …
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Effect of curing temperature on the reaction kinetics of cementitious steel slag-fly ash-desulfurized gypsum composites system. Author links open overlay panel Siyu Duan a, Hao Wu a ... and the time of fifth stage was >30 h and >28 h, respectively. Thus, increases in temperature shortened the reaction times of each stage, that is …
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According to the ACAA (American Coal Ash Association), 1 chloride content in the desulfurized gypsum should be reduced to below 400 ppm. ... temperature has an influence on the mass that the …
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The number of inquiries to the Gypsum Association about water-damaged gypsum panels always increases during the winter, early spring, after hurricane season or after any other significant water exposure event. Answers to many of these questions are found in an Association document revised in 2019, GA-231 Assessing Water Damage to …
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It can be seen that the dissolution rate of anhydrite in the system is lower, the cement clinker mixed with desulfurized gypsum produces more ettringite at the same hydration age, and the consumption rate of C 4 A 3 $ is slower, ... calcination temperature, and other factors in the calcination process of clinker were determined, …
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DOI: 10.1016/j.conbuildmat.2023.131840 Corpus ID: 258997305; Effects of hybrid fibers on properties of desulfurized gypsum-based composite cementitious materials @article{Lv2023EffectsOH, title={Effects of hybrid fibers on properties of desulfurized gypsum-based composite cementitious materials}, author={Fangtao Lv …
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of desulfurized gypsum conforms to the concept of green and low-carbon development. ... The calcination-treated FGD gypsum would not influence the type ... The decomposition of chemical-bound water of gypsum can oc-cur when the temperature is higher than 120 °C and the two molecular H
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The utilization of desulfurized building gypsum as raw material for gypsum-based self-leveling mortar (GSL) is limited by its low strength and poor water resistance. ... In addition, the calcination temperature of β-hemihydrate gypsum is significantly lower than that of cement, usually within a range of 135–180 °C, ...
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The high-temperature calcination method (equipment) is that the desulfurized gypsum is in direct contact with the high-temperature flue gas for heat exchange, rapid dehydration and...
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FGD Gypsum: TS = FGD GYPSUM: 2010–01-01 to 2023–05-08: 581: SCI-EXPANDED, SSCI, CPCI-S ... (time taken to reach a temperature of 180 °C on the unexposed side of the board) of 48.2 min (G-C) and 52. ... Rossetto et al., studied the mechanical strength and workability at a fixed calcination temperature of 150 °C for …
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Additionally, it has a more intricate composition than desulfurized gypsum, as the sources of S originate from both CaSO 4 and CaSO 3. ... High-temperature calcination experiments of SFGDA were conducted using a laboratory sintering cup shown in Fig. 3. Download: Download high-res image (236KB) Download: Download full-size …
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What is desulfurization gypsum. Desulfurization gypsum, also known as FGD gypsum (flue gas desulfurization gypsum), is an industrial by-product gypsum obtained by desulfurization and purification of flue gas generated after combustion of sulfur-containing fuel (coal, oil, etc.), and its composition is calcium sulfate dihydrate (CaSO 4.2H 2 O).. …
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