Flue Gas Desulfurization: The State of the Art [J]
of gypsum are accomplished in a single reaction vessel. The contact is achieved by injecting flue gas through gas sparger tubes immersed below the surface of the limestone
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The Key Application Technology of Desulfurized Gypsum in …
Desulfurized gypsum is an industrial by-product gypsum obtained after flue gas desulfurization in coal-fired or oil-fired power plants [1]. Its main components and physical and chemical …
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Performance Characterization and Composition Design Using …
2.2. Test Design. In order to study the flexural strength and compressive strength of slag–desulfurization gypsum-based alkali-activated materials, six factors were selected as the main influencing factors, including desulfurization gypsum, Ca(OH) 2, fly ash, the water–glue ratio, and the content and modulus of the alkaline activator.This study used the orthogonal …
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Enhanced dealkalization of bauxite residue through calcium …
capacity in abating pH rebound. Hence, approach can provide guidance for effectively utilizing desulfurization this gypsum to achieve stable regulation of alkalinity in bauxite residue. Key words: bauxite residue; desulfurization gypsum; EDTA activation; alkalinity regulation; recycled FeCl 3. 1 Introduction . The stacking of strongly alkaline ...
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Preparation of CSHW with Flue Gas Desulfurization Gypsum
1. Introduction. Calcium sulphate hemihydrate whiskers (CSHW) is a fibrous crystal formed by Ca 2+ ions and SO 4 2− ions. Since it is more likely to grow alternately along the C axis, the average aspect ratio of CSHW is usually more than 10 [1,2,3,4].Due to its uniform structure, integral appearance, fine particles, high dispersion, high specific surface area and …
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Factors affecting the precipitation of pure calcium carbonate …
The mineral carbonation of FGD (flue gas desulfurization) gypsum was carried out through CO 2 sorption into ammonia solution containing FGD gypsum. High-purity calcium carbonate was precipitated from DCC (dissolved calcium carbonate) solution which was extracted during the induction period. The factors affecting the preparation of pure calcium carbonate …
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Phosphorus fractions in poultry litter as affected by flue‐gas
The first objective of this work was to evaluate the effect of incubation time and rate of gypsum addition to litter alone or litter mixed with soil on total P and inorganic P in sequential extracts of H 2 O, 0.5 m NaHCO 3, 0.1 m NaOH and 1 m HCl. Poultry litter was mixed with 25, 50, or 75% gypsum (by weight) and incubated alone or mixed with ...
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Preparation of superfine and semi-hydrated flue gas desulfurization
Mechanical grinding has been widely used in the pretreatment of FGD gypsum to address the flaws mentioned above in the cement industry and has been indicate to be a practical and straightforward approach to improving particle size distribution and reactivity [22], [23], [24], [25].However, FGD gypsum invariably needs to be predried since its free water content …
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Solidification and Release Characteristics of Heavy …
Wu et al. studied the loss of mercury in desulfurization gypsum under natural stacking conditions for a time interval of 6–12 months, during which its maximum mercury loss rate was 21.35% at 9 months and was influenced …
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Effect of impure components in flue gas desulfurization (FGD) gypsum …
Limestone/gypsum wet desulfurization technique has been widely used to remove sulfur oxides from flue gas or other industrial waste gas due to its high desulfurization efficiency and stability [1]. It is reported that huge amount of FGD gypsum has generated worldwide, especially in China (80 Mt, 2017) and USA (30 Mt, 2015) whose amount to more ...
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Development of a new magnesium oxychloride cement board by …
The findings reveal that the created stacking ensemble learning model can successfully fuse the prediction outputs of base learners and increase the predictive accuracy of the model. The performance evaluation indices of the established stacking model are as follows: RMSE = 2.344, MAE = 1.764, and R 2 = 0. 987. The developed models were ...
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Preparation of α-High Strength Gypsum from Flue Gas Desulfurization
The synthesis of α-calcium sulfate hemihydrate (α-CSH) from flue gas desulfurization (FGD) gypsum is a good way to realize the comprehensive utilization of FGD gypsum. To obtain α-CSH with the satisfactory performances, a facile hydrothermal-aging pretreatment process for FGD gypsum raw materials was proposed, where FGD gypsum was …
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Enhanced dealkalization of bauxite residue through calcium …
A novel integrated approach to remove the free alkalis and stabilize solid-phase alkalinity by controlling the release of Ca from desulfurization gypsum was developed. The combination of recycled FeCl 3 solution and EDTA activated desulfurization gypsum lowered the bauxite residue pH to 7.20. Moreover, it also improved the residual Ca state ...
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Effect of desulfurization gypsum on alternating-current impedance
Its main components are dihydrate gypsum and hemihydrate gypsum, which have good solubility and are similar to natural gypsum [29], [30]. There are few reports on the effect of different contents of desulfurization gypsum on the formation rate of ettringite. The role of desulfurization gypsum in BSAC hydration remains to be further studied.
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Emission reduction process for dechlorinating flue‐gas …
on producing gypsum boards with higher fire resistance, water resistance, and low density. Existing results show that the thermal insulation capacity of commercial gypsum board is lower than that of FGD gypsum board. 3 Additionally, FGD gypsum board has a higher insulating capacity compared to gypsum board manufactured with different pro-
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Recent advances in flue gas desulfurization gypsum processes …
Flue gas desulfurization gypsum (FGDG) is an industrial by-product generated during the flue gas desulfurization process in coal-fired power plants. ... 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) Finely ...
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Performance Characterization and Composition Design Using …
2.1. Test Materials. The raw materials involved in this study are as follows: slag, fly ash, Ca(OH) 2, desulfurization gypsum, Na 2 SiO 3, NaOH, nano-SiO 2, and water, as shown in Figure 1.The purpose of incorporating nano-SiO 2 is to improve the strength of the material. In this study, the S95 slag came from Gongyi Longze Water Purification Materials Co., Ltd., Gongyi City, China, …
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Promotion of conversion activity of flue gas desulfurization …
improved the conversion activity of FGD gypsum, thereby promoting dihydrate gypsum (DH) dissolution and α-HH nucleation. Overall, the phase transition of FGD gypsum to α-HH is …
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Production and resource utilization of flue gas desulfurized gypsum …
Three significant industrial gypsum by-products are flue-gas desulfurization gypsum (FGDG) [13], which is produced from coal combustion after the wet desulfurization of flue gas; phosphogypsum (PG ...
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Quantifying the Benefits of Using Flue Gas Desulfurization …
(11.2 Mt) of the CCPs consisted of gypsum from flue gas desulfurization (FGD). The desulfurization process uses wet scrubbers and forced oxidation to reduce SO. 2. emissions, and the gypsum produced is mineralogically identical to natural gypsum (CaSO. 4?2H. 2. O), making FGD gypsum an ideal replacement for the mined gypsum used to manufacture ...
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Properties and hydration mechanism of eco-friendly binder from
During the 3–28 days curing, gypsum and Ca/(Si+Al) molar ratio of gels decreased by 10.9% and 0.61 respectively, and the weight loss rate was 3.85%, which indicated that gypsum reacted ...
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Effectiveness of flue gas desulfurization gypsum in reducing …
One strategy that has been tested to reduce P loss from agricultural fields is to apply a soil amendment such as gypsum (Dou et al., 2003, Moore and Miller, 1994, Watts and Dick, 2014, Watts and Torbert, 2009).Amending soils with gypsum helps reduce the loss of soluble P under a broad range of manure loading, pH, and redox conditions, and also for soils …
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Study on performance and function mechanisms of whisker modified …
The raw materials used in this study included flue gas desulfurization (FGD) gypsum, anhydrous calcium sulfate whiskers (ACSW), calcium carbonate whiskers (CW), and protein retarders. The FGD gypsum was provided by Beijing New Building Materials Public Limited Company, which was obtained by special calcination treatment of CaSO 4 ·2H 2 O. …
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Effect of Combined Application of Desulfurization Gypsum and …
Saline-alkali soil imposes severe adverse effects on soil utilization and agriculture production worldwide. Amelioration of saline-alkali soil is crucial to ensure global food security and promote sustainable agricultural development. Here, the effects of the combined application of soil amendment desulfurization gypsum (G) and KIA (K, an industrial organic by-product) on soil …
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Desulfurization gypsum uses and properties
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 …
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Study on performance and function mechanisms of whisker …
The raw materials used in this study included flue gas desulfurization (FGD) gypsum, anhydrous calcium sulfate whiskers (ACSW), calcium carbonate whiskers (CW), and protein retarders. The FGD gypsum was provided by Beijing New Building Materials Public Limited Company, which was obtained by special calcination treatment of CaSO 4 ·2H 2 O. …
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The Key Application Technology of Desulfurized Gypsum in …
mortar reaches the maximum At the same time, the best content of desulfurization gypsum is 6%. 3.3 The influence of Portland cement on the bulk density of mortar Figure 2 shows the effect of Portland cement content change on the freshly mixed bulk density and 28d hardened bulk density of desulfurized gypsum-based mortar.
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Influence of Carbon and Pyrite on Desulfurization Behavior of …
as a solid waste [2 ]. Gypsum (CaSO 4 ·2H 2 O) and amorphous ferric hydroxide (Fe(OH) 3) are major components of the red gypsum [3]. Roughly, 5–6 tons of red gypsum is generated for every ton of TiO 2 using the sulfate method. Annually, 15 million tons of RG is generated in China [4 ]. In general, RG is treated by outdoor stacking, which
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Phosphorus fractions in poultry litter as affected by flue‐gas
Previous research has shown that the addition of flue‐gas desulphurization (FGD) gypsum to poultry litter decreases water‐soluble P. No information is currently available, however, on extractable P fractions in poultry litter and P availability as affected by gypsum. The first objective of this work was to evaluate the effect of incubation time and rate of gypsum addition to litter …
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Utilization of ultra-fine desulfurization ashes in supersulfated
As the amount of UFDA increases, the setting time of UPG-SSC increases. Research shows that the presence of gypsum increases the solubility of sulfites. The CaSO 3 …
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