Synergistic effect of red mud, desulfurized gypsum and fly …
The synergistic effect of red mud – desulfurized gypsum - fly ash was found. ... Influence of water re-curing on microstructure of heat-damaged cement mortar characterized by low-field NMR and MIP. Constr. Build. Mater., 262 (2020), Article 120532. View PDF View article View in Scopus Google Scholar
CN113683333B
The invention discloses a desulfurized gypsum retarder, a preparation method and application thereof in sulphoaluminate cement, wherein the method comprises the following steps: the temperature of the rotary kiln is reduced from 300 ℃ to 400 ℃, the temperature reduction process is divided into a plurality of temperature reduction sections, the desulfurization gypsum is …
Advances on resource utilization of semi-dry …
Through the method of heat decomposition, the SFGDA decom-posed into CaO and SO 2 ... Keywords SFGDA · Thermal treatment · Low-temperature · Decomposition · Circulation reuse Introduction SO 2, the primary culprit behind acid rain, poses signi- ... waste liquid and desulfurized gypsum, severely impeding its marketability and utilization. As ...
Study on desulfurized gypsum used as cement retarder
The results showed that when the content of desulfurized gypsum after 80 °C heat treatment was 4% of Portland cement, the initial setting time was 136min, and the final setting …
Heat Treatment Process of the Flue Gas Desulphurization …
The Crystal Transformation of flue gas desulphurization (FGD) gypsum was analyzed by differential thermal analysis (DTA) and X-ray Diffraction (XRD). FGD gypsum was used as …
Study on the influence mechanism of flue gas desulphurisation gypsum …
Flue gas desulphurisation gypsum (FGDG) mainly refers to the solid by-product produced via lime gypsum desulphurisation that is performed in various industries to treat flue gas after the combustion of sulphur-containing fuels, such as coal and petroleum [1].In the limestone gypsum flue gas desulphurisation process, 2.7 tons of FGDG can be produced for every 1 ton …
Condensational growth activated by cooling method for …
The desulfurized flue gas from coal-fired power plants is discharged with pollutants and a lot of heat and water vapor into the environment. To synchronously reduce the pollutant emission and recover the heat and water, a novel technology was proposed and applied in a coal-fired power plant after experimental and pilot studies.
Development and Application of Flue Gas Desulfurized Gypsum …
Under the effect of humidity–heat cycles, ... which can be rapidly and completely degraded by ordinary biochemical treatment, causing no pollution to the natural environment. ... 2024. "Development and Application of Flue Gas Desulfurized Gypsum and Blast-Furnace-Slag-Based Grouting Material for Cracked Silty Mudstone" Materials 17, no. 23: ...
Utilizations of preheated flue gas desulfurization gypsum …
Current study proposes an effective way to modify the properties of super-sulfated cement (SSC) paste and mortar with preheated flue gas desulfurization (FDG) gypsum at different temperatures and durations, and different sulfate compositions. Preheated FGDs with temperatures between 25 and 150 °C and durations between 0 and 24 h were used to replace …
Comparative Analysis of Hydration Expansion Performance of Desulfurized …
The heat-treatment of the ACF at 800°C was found very ... Using desulfurized gypsum and steel slag as raw material make desulfurized gypsum-steel slag composite gelled material, by adding cement ...
Application of Flue Gas Desulfurization Gypsum …
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 …
Study on desulfurized gypsum used as cement retarder
The effects of desulfurized gypsum, heat-treated desulfurized gypsum and hydrogen peroxide modified desulfurized gypsum on the setting time of Portland cement were studied. The results showed that when the content of desulfurized gypsum after 80 °C heat treatment was 4% of Portland cement, the initial setting time was 136min, and the final ...
Study on desulfurized gypsum used as cement retarder
The effects of desulfurized gypsum, heat-treated desulfurized gypsum and hydrogen peroxide modified desulfurized gypsum on the setting time of Portland cement were studied. The results showed that when the content of desulfurized gypsum after 80 ℃ heat treatment was 4% of Portland cement, the initial setting time was
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 ...
A comprehensive review of flue gas desulphurized gypsum: …
The thermal gravimetric analysis accounts for 18 – 20 % weight loss (Fig. 8 b) during heat treatment (120 – 150 °C), which is ascribed to loss of bound water as FGDG gets ... FGDG comprises B that can be readily leached out on the treatment of soil with gypsum, as it is soluble in water. It causes a higher concentration of B in ...
Influence of Calcined Flue Gas Desulfurization Gypsum and …
At present, the industrial utilization of desulfurized gypsum has become one of the main research directions of scholars. Comprehensive utilization of desulfurized gypsum conforms to the concept of green and low-carbon development. ... based on the heat patterns . ... After thermal treatment, ...
Investigation on the compressive strength of desulfurization gypsum …
The ultra-high addition of 20 % desulfurized gypsum is beneficial to improve the strength of DG-based binary cementitious materials with low energy consumption. ... ecological and environmental issues. Currently, most of the solid waste disposal methods are landfill and stockpile treatment ... and the compressive strength was up to 37 MPa by ...
CN111569813A
The invention provides a crystallization and solid-liquid separation device for desulfurized gypsum, which comprises a constant-temperature heating device, a reactor, a split-flow sorting device, a reaction liquid adding device and a crystal discharging device, wherein the reactor is provided with a plurality of reaction liquid inlets; the reactor is placed in the constant-temperature heating ...
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 …
High value-added utilization of desulfurized building gypsum …
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 effectively applied in practical …
Desulfurized gypsum-high-calcium fly ash geopolymer …
Desulfurized gypsum-high-calcium fly ash geopolymer cementing material and preparation method thereof. Patent. CN-101857387-A. Inventor. XIAOLU GUO . HUISHENG SHI . Assignee. UNIV TONGJI . Country. China .
Resource utilization of flue gas calcium-based …
Chen [] made statistics on the main physical phases of CDA from steel plant sintering machines and coal-fired power plants, and the results are shown in Table 2.Among the many components, CaSO 3 contains the highest percentage, which is generated by the reaction between SO 2 and lime in the flue gas. The CaCO 3 content is also higher because the flue …
Promotion of conversion activity of flue gas …
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 …
The Effect of FGD Gypsum Heat Treatment Process on …
The influence of different heat treatment processes on the strength of cements was not obvious and the strength development was good. The water consumption of normal consistency for cements changed slightly. ... Research on Performances of Cement and Concrete with Desulfurized Gypsum as Retarder. Coalash, 2011, 4: 24-26.
CN101857387A
The invention discloses a desulfurized gypsum-high-calcium fly ash geopolymer cementing material and a preparation method thereof. In the geopolymer cementing material, high-calcium fly ash is used as a main raw material, desulfurized gypsum after heat treatment is used as a mineral admixture, and a solution prepared by sodium hydroxide and liquid sodium silicate is used as a …
High value-added utilization of desulfurized building …
The utilization of desulfurized building gypsum as raw material for gypsum-based self-leveling mortar ... the rheological parameter, heat of hydration, crystal morphology, and pore structure were also analyzed. Cement greatly improved the uidity of slurry. Moreover, the compressive ... napping treatment, early-age curing and joint-cutting, thus ...
Heat Treatment Process of the Flue Gas Desulphurization Gypsum …
The Crystal Transformation of flue gas desulphurization (FGD) gypsum was analyzed by differential thermal analysis (DTA) and X-ray Diffraction (XRD). FGD gypsum was used as cement setting retarder and the influences on the properties of cement were studied by treating FGD gypsum at different heat treatment processes. The results reveal that in the case of adding the …
Emission reduction process for dechlorinating flue‐gas desulfurization
In addition, although the water of crystallization content in gypsum varies with the conditions of its immediate environment, such as temperature or humidity, 60 the chemical composition of gypsum does not change after heat treatment (Equations 3 and 4). 61 However, FGD gypsum cannot be used to manufacture plaster without heat treatment. 4
Steering the early strength of clinker-free cementitious …
The binders used in this study included granulated blast furnace slag (GBFS), steel slag (SS) and desulfurized gypsum (DG). Wet DG was provided by a thermal power plant, SS and GBFS were provided by a steel smelting facility in Shanxi province. The chemical compositions of the above raw materials are shown in Table 1.
Advances on resource utilization of semi-dry desulfurization …
The semi-dry flue gas desulfurization ash (SFGDA) is an industrial waste generated by the semi-dry desulfurization process, and its resources have been continuously attracted attention. Through the method of heat decomposition, the SFGDA decomposed into CaO and SO2 has emerged as a prominent research topic. This paper summarizes various of research …