Desulfurized Gypsum Crystal Environment Ph Value
High value-added utilization of desulfurized building gypsum …
2.1. Raw materials. The desulfurized β-hemihydrate gypsum (density; 2.497 g/cm 3 and specific surface area; 330.14 kg/m 2) was obtained from Chongqing Yuju Environmental Protection Technology Co., LTD.The 42.5R Ordinary Portland Cement (similar to ASTM C150 Type I Cement) was obtained from Chongqing Fuhuang Cement Co., LTD (density; 3.132 g/cm 3 and …
(PDF) AMELIORATION OF ALKALIZED SOLONCHAK SOILS BY …
This study aims to investigate the subsurface gravel ditches and desulfurization gypsum (DG) as amelioration methods for alkalized solonchak soils in Gansu Jingyuan of China (37°02' N, 104°96' E).
Effect of desulfurized gypsum whiskers on the adsorption …
Sintering process made red mud and desulfurized gypsum whiskers adhere evenly and closely, inducing the spilling out of crystal water to form porous structures favorable for the adsorption of Pb(II). ... until to a constant pH value. Put 100 mL of Pb ... resulting in a carbon-thermal reaction environment. In the regulation of crystal growth, ...
Utilization of flue gas desulfurization gypsum to produce …
The Yellow River is the most sediment-laden river on earth, with a maximum annual sediment load of 3.91 × 10 9 t (in 1933) and a maximum sediment concentration of 972 kg/m 3 (in 1977) (Zhang et al., 2020). The large amount of sediment deposition of the Yellow River not only occupies a large area of land, but also easily causes flood hazards, and tends …
Phase- and morphology-controlled crystallization of gypsum …
The FGD gypsum is obtained from Zhong Wei power plant (Ningxia Province, China), and is used as raw material for the following experiments. HCl (>37% v/v purity) and C 2 H 5 OH (>99.7% v/v purity) are purchased from Beijing Chemical Reagent Co. Ltd. SDS (>98% purity), sodium stearate (9.6%–10.6% purity), and CTAB (>99% purity) are purchased from …
A comprehensive review of flue gas desulphurized gypsum: …
Flue Gas Desulphurized Gypsum (FGDG) is a by-product generated by the thermal power industry to remove sulfur dioxide (SO 2) from flue gas emissions. This paper …
VWHP
The pH value of the slurry was analyzed by a pH meter. The test results showed that the pH of the limestone sludge slurry was 8.31, the pH of the desulfurized limestone slurry was 6.41, and the pH of the limestone slurry was much higher than that of the desulfurized limestone slurry. 3.3. Reactive activity
A Comprehensive Evaluation of the Effect of Desulfurized Gypsum …
ObjectiveIn order to comprehensively study the effect of desulfurized gypsum in improving saline-alkali soils, this paper statistically analyzed the change characteristics of soil pH value, exchangeable sodium percentage (ESP), soil electrical conductivity (EC), and crop yield after applying 0~60 t·hm -2 desulfurized gypsum in the northwest, north, northeast, and coastal …
Characterization of flue gas desulphurized (FGD) gypsum of …
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.
Optimization design and characterization of slag …
Desulfurization gypsum (DG) is an industrial solid waste obtained by using lime to recover SO 2 gas in flue gas. Its chemical reaction process is shown in equation (1).Due to the limited effective treatment methods, a large amount of DG dumped has an unavoidable negative impact on environment [13].The main chemical composition of DG is CaSO 4 ·2H 2 O, which …
AMELIORATION OF ALKALIZED SOLONCHAK SOILS BY …
DG application rate, the values of pH, exchangeable sodium percentage (ESP) and electrical conductivity (EC) of the soil layer up to 40 cm from the surface were decreased by 11.0%, 38.1% and 34.5%, respectively, than those of the control which had no blind ditch and DG treatment in the first year. The yield of Chinese wolfberry
Application of Flue Gas Desulfurization Gypsum and Its Impact …
F lue gas desulfurization gypsum (FGDG) is a synthetic gypsum that is created during the removal of SO 2 from flue gas by reacting the SO 2 with calcite (CaCO 3) to form calcium sulfite (CaSO 3 ·0.5H 2 O), which is further treated with wet limestone and forced oxidization to form calcium sulfate (CaSO 4 ·2H 2 O) (Laperche and Bigham, 2002).Synthetic …
Utilization of low-quality desulfurized ash from semi …
hydrate gypsum and desulfurized ash are given in Fig. 1 A. The specific surface areas of desulfurized ash and hemihydrate gypsum are 351 and 328m2/Kg respectively. And the XRD patterns of desulfurized ash and α- hemihydrate gypsum are shown in Fig. 1B. 2.2. Sample preparation All the specimens were kept as the constant value of 180mm as the
Utilization of low-quality desulfurized ash from semi-dry …
It can be seen from the results that desulfurized ash has an important influence on the water requirement for the normal consistency. The control, namely the hemihydrate gypsum without desulfurized ash, provides with 0.47 water requirement. However, the hemihydrate gypsum with 8% desulfurized ash displays a water requirement of 0.49 and it is ...
High value-added utilization of desulfurized …
This work was expected to provide reference for promoting the application of desulfurized building gypsum as the high value-added screed. Chemical compositions of raw materials (wt.%). Mix ...
Production and resource utilization of flue gas desulfurized gypsum in China
In this study, a simple hydrochloric acid solution method was employed to convert solid waste FGD gypsum and the confinement sodium dodecyl sulfate (SDS) was used to …
Experimental Study on the Properties and …
In order to achieve the resourceful, large-scale and high-value utilization of bulk industrial solid wastes such as flue gas desulfurization gypsum (FGDG), fly ash (FA) and ground blast furnace slag (GGBS), and to reduce …
Effect of desulfurized gypsum whiskers on the adsorption
The study investigated the impact of red mud / desulfurized gypsum whiskers mass ratio, coupling agent dosages and calcination temperature on the Pb(II) adsorption by …
Influence of Reaction Parameters on Solid Outputs in …
The solid product calcium carbonate crystal form of the direct mineralization reaction in the desulfurized gypsum ammonia water system has only two crystal forms: vaterite and calcite, and no aragonite was detected. Therefore the content of vaterite and calcite is calculated by the following two formulas [10]: 110 104 CC X VI (1) XXVC 1 (2)
A brief review on flue gas desulfurization gypsum recovery …
The past several years have witnessed great progress in utilization of industrial waste gypsum. Newly developed carbonation technology toward CaCO 3 preparation also reveals a significant utilization way to recover high-value products from waste gypsum, whereas there is a shortage of systematic reviews reporting the most recent progress in carbonation of flue gas …
Flue Gas Desulfurization Gypsum
The semi-hydrate content of desulfurized gypsum is adjusted as a natural plaster substitute for producing gypsum board, wallboard [107].The modified treatment of desulfurized gypsum with cement, inorganic waste, straw fiber and other wastes can be used to manufacture high-insulation and compression-resistant wall materials [108].Desulfurized gypsum is incorporated into the …
Experimental Study and Mechanism Analysis of Preparation …
Flue-gas desulphurization (FGD) gypsum is a highly prevalent industrial by-product worldwide, which can be an excellent alternative to natural gypsum due to its high content of CaSO4·2H2O. The preparation of α-calcium sulfate hemihydrate is a high-value pathway for the efficient use of FGD gypsum. Here, a dynamic method, or an improved autoclaved process, …
Experimental Study on the Properties and Hydration Mechanism of Gypsum
(2) As shown in Equations (2)~(4), the hydration of C 3 S and C 2 S in OPC generates flocculent C-S-H gel and flaky CH, which can regulate the pH value of the slurry to an environment suitable for the growth of the crystal form, which is conducive to the growth of gypsum crystals, so that the dense structure formed by hydration products lapped ...
Utilization of flue gas desulfurization gypsum to produce …
During planting, the pH of SDS decreased rapidly to about 8.5, mainly because the root respiration accelerated the carbonization of Ca (OH) 2 crystals in sample. 1. Introduction.
Properties and microstructure of soil solidified by titanium …
Using Portland cement for soil solidification has sustainability issues due to high energy-consumption and carbon emissions.An innovative approach suggests using titanium slag and flue gas desulfurized gypsum as substitutes for Portland cement for soil solidification. This study systematically evaluates the effects of titanium slag-flue gas desulfurized gypsum …
Summary of research progress on industrial flue gas desulfurization
The semi-hydrate content of desulfurized gypsum is adjusted as a natural plaster substitute for producing gypsum board, wallboard [107]. The modified treatment of desulfurized gypsum with cement, inorganic waste, straw fiber and other wastes can be used to manufacture high-insulation and compression-resistant wall materials [108] .
Production and resource utilization of flue gas desulfurized gypsum …
The main utilization method of FGD gypsum is still used in construction materials (Ye et al., 2019). As an auxiliary material or instead of natural gypsum, it can be widely used in concrete, walls, concrete, etc. It is the best way to use desulfurized gypsum in large quantities, but its economic value is relatively low (Pedreno-Rojas et al., 2020).
Characterization of flue gas desulphurized (FGD) …
The FGD gypsum samples had an average pH value of 8.73 and EC 4.87 dS m −1. The calcium carbonate percentage ranged from 15 to 17% for different FGD gypsum samples with a moisture content of...
(PDF) Effect of different soluble salt ions on …
The results show that: (1) in the environment of a single salt solution, K^+ ion, 〖Mg〗^ (2+) ion, 〖Na〗^+ ion, and 〖Cl〗^- ion will cause sagging deformation of desulfurization gypsum, and their...
Utilization of low-quality desulfurized ash from semi-dry …
This work aimed to investigate the feasibility of utilizing the low-quality desulfurization ash from semi-dry flue gas desulfurization by mixing with α-hemihydrate gypsum, and then the environmental issues resulted from low-quality desulfurized ash from semi-dry flue gas desulfurization can be resolved, and both economic and ecological benefits are brought to …
High value-added utilization of desulfurized building gypsum …
Desulfurized building gypsum (DBG) has great application potential and can be used to produce lightweight plastering gypsum (LPG). In this work, DBG was modified by adding different proportions of ...
Desulphurization mechanism and engineering practice of …
CS desulfurization pH is not easy to control, easy to block the pipeline, gypsum moisture content is high, and dehydration is not easy. The pH of CS slurry is 12.45, and that of desulfurized gypsum is 3.33. The pH span is large and difficult to control, which will lead to the oxidation of CS desulfurized gypsum and the formation of CaSO 3 ·0 ...