The paper discusses the chemical and physical properties of FGD gypsum, including its composition, crystal structure, particle size, and moisture content. It also reviews the various applications of FGD gypsum, such as in cement and concrete …
Current study proposes an effective way to modify the properties of super-sulfated cement (SSC) paste and mortar with preheated flue gas desulfurization (FDG) …
The SEM images of FGD gypsum 1 (Fig. 3a) and FGD gypsum 2 (Fig. 3b) showed the presence of a clear flaky crystal-like structure of gypsum in both the FGD gypsums 18,25.
In order to explore the influence of the types of waste gypsum on the properties of alkali slag cement, fluorogypsum (FG) and flue-gas desulfurization (FGD) gypsum were comparatively investigated. Moreover, the action mechanisms of FG and FGD gypsum on the properties of alkali slag cement were analyzed. The results …
Little attention has thus far been paid to the potential effect of solution composition on the hydrothermal crystallization of calcium sulfate whiskers prepared from flue-gas desulfurization (FGD ...
Abstract. As a relatively fast-setting building material, desulfurized gypsum is difficult to use. Citric acid, sodium gluconate, and sodium tripolyphosphate were used to design and prepare a desulfurized gypsum paste containing single or combined retarders. The effects of the retarder type and content on the setting inhibition and mechanical …
The mechanical properties of FGD gypsum improved greatly because the whiskers can increase the contact points between the crystals and fill the pores in FGD gypsum.
In this research, the influence of desulfurized gypsum (FGD) with different carbon removing methods of 0.3 mm sieving, and 500^{circ}C high temperature combustion on high volume blast furnace ...
Heavy metals in flue gas desulfurization (FGD) gypsum from coal-fired power plants are at risk of releaching during the processes of stockpiling and resource …
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 …
Flue gas desulfurized gypsum (FGDG) is an industrial by-product discharged from thermal power plants, smelters, and large-scale enterprise boilers. ... the addition of pozzolanic material will generate a lot of hydrated calcium silicate (C–S–H) wrapping around the gypsum crystals, which prevents the dissolution of gypsum and …
To resolve the limited large-scale methods of disposal of low calcium fly ash with poor activity, based on the double excitation principle, clinker and desulfurized gypsum are used as alkali/salt activators to activate fly ash and slag, avoiding the inconvenience of strong alkali activating fly ash in industry. Firstly, the strength test of a …
In order to improve the early strength of fly ash blended cement concrete under steam curing conditions, fly ash was partly substituted by calcined flue gas desulfurization (FGD) gypsum and active calcium aluminate. The effect of the composition and curing condition on the workability, mechanical property, and volume stability was …
The production of flue gas desulfurization gypsum poses a serious threat to the environment. Thus, utilizing gypsum-based self-leveling mortar (GSLM) stands out as a promising and effective approach to address the issue. β-hemihydrate gypsum, cement, polycarboxylate superplasticizer, hydroxypropyl methyl cellulose ether (HPMC), retarder, …
The concentration of particulate matter (PM), SO2, NOx, SO3, HCl, HF, and PM2.5 were measured in a 330MW ultra low emission coal-fired power unit.
Understanding and controlling these influencing factors of the crystallization process and directing the synthesis process to produce products with expected properties may have a significant effect on the large-scale preparation of α-HH. ... Hu, Y.; Yin, Z.; Guan, C. A facile method of transforming FGD gypsum to α-CaSO 4 …
The effective and safe use of FGD gypsum in agricultural land is still debated in some countries even though its effectiveness in soil management has been reported in many studies. Thus, the changes in …
T. Lei et al. conducted desulfurization experiments with red mud slurry using the Bayer method. The results showed that L/S was the dominant factor affecting desulfurization, …
The main objective of this study is to explore factors influencing gypsum recycling and landfilling in the EU-28. ... and the rest of the world (5%). The paper discusses the chemical and physical properties of FGD gypsum, including its composition, crystal structure, particle size, and moisture content. It also reviews the various applications ...
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. The objective of this study is to enhance comprehensive properties of GSL and prepare qualified desulfurized building gypsum-based self-leveling mortar that can be …
The results show that changing the structure of solid gypsum leads to the increase in bending and compressive strength by 70,5% and 138% correspondingly, the water resistance increasing and the ...
Besides, even after curing for 28 days, some Ca(OH) 2 crystals (CH) shaped in regular flake-like structure were also observed in Fig. 14, which was the main factor leading to the higher pH value of SDS samples. It is worth noting that many of the irregular columnar and blocky structures in Fig. 14 were hydrated gypsum crystals …
A dynamic batch crystallization reactor was used to study the characteristics of gypsum crystallization in wet flue gas desulfurization. Through this study, the results can be concluded that the ...
In this research, the influence of desulfurized gypsum (FGD) with different carbon removing methods of 0.3 mm sieving, and 500^{circ}C high temperature combustion on high volume blast furnace ...
The surface hardness of desulfurized gypsum (BS) without crystal modifier is 21.94, as shown in Fig. 9. The surface hardness of the generated high-strength gypsum is mainly increased after the crystal modifiers BTCA, SC, and CA are added. ... and nucleation energy of gypsum crystals, influencing the formation of hemihydrate …
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).. …
Wu et al. (2018) studied the influence of desulfurized gypsum reaction temperature, glycerin concentration, raw material particle size, and seed crystal on CSW morphology in a glycerol aqueous solution. Studies have shown that the average CSW diameter decreases and the average aspect ratio gradually increases as the particle size …
•. Micronization occurred securely without machine downtime due to high temperatures. •. Desulfurization tests show greater performance in terms of gypsum …
Semantic Scholar extracted view of "Study on the influence mechanism of flue gas desulphurisation gypsum on solid waste-based geopolymer grouting materials" by Dedan Duan et al. ... Effect of curing temperature on the reaction kinetics of cementitious steel slag-fly ash-desulfurized gypsum composites system. Siyu Duan Hao Wu Ke …
Under the condition of desulfurization in coal-fired power plants, DDBAC and CMI can promote the growth of gypsum, transform the shape of gypsum into plate crystal, and …
In the limestone gypsum flue gas desulfurization process, 2.7 ton of desulfurized gypsum can be generated for each 1 ton of SO 2 removed . A 300 MW coal-fired thermal power unit discharges about 30,000 ton of desulfurized gypsum every year (assuming 1.0% sulfur in coal) . A substantial amount of desulfurized gypsum is …
Since many independent factors can affect the property of geopolymer, it is of great significance to seek optimization technologies to maximize the recovery and utilization of solid waste resources.In this work, a cementitious material was prepared using ground granulated blast furnace slag (GGBS), carbide slag (CS) and desulfurized …
Flue gas desulfurized gypsum (FGD gypsum), mainly originates from thermal power plants, smelters, and large-scale enterprise boilers. This article reviews …
