Synergistic effect of red mud, desulfurized gypsum and fly …
Synergistic effect of red mud, desulfurized gypsum and fly ash in cementitious materials: Mechanical performances and microstructure. Author links open overlay panel Yaguang Wang a, Xiaoming Liu b, ... RFC20 and RFDC6 in each temperature range. The weight loss of RC50, RFC20 and RFDC6 at 45–200 ℃ are 7.88%, 10.41% and 14.14%, respectively ...
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High value-added utilization of desulfurized building …
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 Dvorkin 2016; Krejsova et al. ... In summary, desulfurized gypsum, an industrial by-product produced by ue gas desulfurization process, is the most practical engineering ...
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Moisture in Gypsum Panel Products
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 Gypsum Board. …
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Calcination of calcium sulphoaluminate cement using flue …
The highest compressive strengths of 63.3, 85.3, 102.8 MPa were attained at 1, 3, and 28 d, respectively when the temperature was kept at 1310 °C for 60 min. Results also indicate that the FGD gypsum decomposition, which is mainly influenced by calcination temperature, retention time and alumina–silica ratio, has a significant impact on the ...
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Influence of Calcined Flue Gas Desulfurization Gypsum and …
The calcination-treated FGD gypsum would not influence the type and morphology hydration products of the calcium sulfur aluminate cement ... The decomposition of chemical-bound water of gypsum can occur when the temperature is higher than 120 °C and the two molecular H 2 O can be released ... The desulfurized gypsum also dissolved ...
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Desulfurization gypsum used as a treatment process for building gypsum
The properties of dihydrate gypsum will continue to disappear with the increase of calcination time. The desulfurized gypsum is calcined for 1.5h After that, it can be converted into semi-hydrated gypsum. ... If the calcining temperature of desulfurized gypsum is at 185℃, 235℃ and 300℃, the main component of the calcined desulfurized ...
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Elemental sulfur recovery from FGD gypsum and calcium …
Flue gas desulfurization (FGD) gypsum mainly contains gypsum, which comes from the FGD by using lime or limestone. The effects of calcining temperature and time on …
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Review A comprehensive review of flue gas desulphurized …
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 6 h) [158]. …
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Gypsum Calcining
Calcination of Gypsum was an accidental discovery as were its rehydration characteristics. Ancient man probably used lumps of Gypsum to enclose his fire. Some degree of calcination and softening occurred and when the fire was extinguished with water he noticed the lumps soon hardened. ... The boiling temperature of 250°-260°F continues for 45 ...
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Study on improving properties of desulfurized gypsum …
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 Portland cement …
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Calcination Processes | Gypsum: Connecting Science and …
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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Calcining processes for natural and synthetic gypsum
Precise and optimally matched to your raw material: with a wide range of calcining processes, Grenzebach supports the high-quality processing of the raw material into stucco or high-fired plaster.
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Effect of curing temperature on the reaction kinetics of …
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 increasing the ...
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Recent advances in flue gas desulfurization gypsum …
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), pp. 24-30. View PDF ...
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Experimental investigation of utilizing waste flue gas desulfurized …
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 temperature ...
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Production and resource utilization of flue gas desulfurized …
The calcination of FGD gypsum is used as a phosphate adsorption material to treat phosphate wastewater. Roasting improves the adsorption performance of FGD gypsum …
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Effect of Polyethylene-Grafted Maleic Anhydride on the
Semidry desulfurization and wet desulfurization in a furnace are usually used in the circulating fluidized bed boiler in the power production of thermal power plants, and these two approaches lead to high calcium content in the fly ash and bottom slag of circulating fluidized beds and produce abundant flue-gas desulfurized (FGD) gypsum [].The gross production of …
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Desulfurization gypsum rotary dryer calcination …
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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Calcining processes for natural and synthetic gypsum
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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A Feasible Route for Preparation of Calcium …
Calcium sulfate whiskers (CSWs) were synthesized using purified flue-gas desulfurization (FGD) gypsum as raw materials using a hydrothermal method, where the filtrate was recycled back to the reaction slurry. The study …
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Utilization of Desulfurization Gypsum to Producing SO
In the oxidizing atmospheres, the decomposing temperature for gypsum is over 1,350°C, while, in the reducing atmosphere, the initial temperature for starting decomposition decreases to 950–1,000°C depending on the atmosphere and impurity, which is suitable for fluidized bed operation. The fast mass transfer between the gas and solid, long ...
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Clay calcination technology: state-of-the-art review by the …
For the production of LC 3, grinding may be used to obtain a uniform and intimate mixture with clinker, limestone, and gypsum [92, 119]. The cement can also be produced by blending components after separate grinding. ... Ferreiro S et al (2019) Influence of fineness of raw clay and calcination temperature on the performance of calcined clay ...
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Effects of different gypsum varieties on the hydration and …
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, and the clinker ...
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Comparative Analysis of Hydration Expansion Performance of Desulfurized …
It is mainly beca use the calcination temperature fo r . ... Using desulfurized gypsum and steel slag as raw material make desulfurized gypsum-steel slag composite gelled material, by adding ...
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Production and resource utilization of flue gas desulfurized gypsum …
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 Chinese ...
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Recent advances in flue gas desulfurization gypsum …
The produced calcium sulfite (CaSO 3 ·2H 2 O) is then oxidized, resulting in FGDG. CaSO 3 ·2H 2 O (aq) + ½O 2 (g) ↔CaSO 4 ·2H 2 O (s) Natural oxidation processes may …
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Review A comprehensive review of flue gas desulphurized gypsum …
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 different time periods ...
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Calcination
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-fastness and thermal stability of …
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All Things Gypsum The Moisture in Gypsum | Walls & Ceilings
However, the water of hydration (mentioned earlier) may also be driven off during the convection oven test if the oven is operated at too high a temperature or if the gypsum board specimen is left in the oven too long. This evaporation of chemically combined water in the gypsum core is commonly referred to as "calcination."
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Influence of Calcined Flue Gas Desulfurization Gypsum …
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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