Thermodynamic study of the desulfurization process of …
In this study, we used thermodynamic calculations to analyze the material and energy balances of the phosphogypsum desulfurization process and to calculate the energy …
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Advances in Phosphogypsum Calcination and …
Miao et al. 29 proposed the production of CaO and SO 2 by the decomposition desulfurization of gypsum using a multistage fluidized bed with multiple atmospheres and verified the feasibility …
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Preparation of α-High-Strength Hemihydrate from Flue Gas
An industrially feasible process was proposed to produce α-calcium sulfate hemihydrate (α-HH) from FGD gypsum without any additives. In this process, an AlCl3 solution was used to promote the conversion of calcium sulfate dihydrate (DH) to hexagonal prismatic α-HH with high strength at atmospheric pressure. The phase transition kinetics of FGD gypsum …
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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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Amendment of Saline–Alkaline Soil with Flue-Gas Desulfurization Gypsum …
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.
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Prospects of using flue gas desulfurization gypsum to
The application of flue gas desulfurization (FGD) gypsum to ameliorate saline-alkaline soils not only provides a new use for FGD gypsum, but also provides a new method for improving saline-alkaline soils. This paper reviews the development of this technology for ameliorating saline-alkaline soils over the past 20 years including the basic theory, key technologies, short and …
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Preparation of gypsum with high purity and whiteness from phosphogypsum …
Phosphogypsum (PG) is a hazardous industrial solid waste product from the wet phosphate industry 1,2.The widespread deposition of that fine, light- to dark-grey, powder with a slight odor and ...
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Agricultural Uses for Flue Gas Desulfurization (FGD) Gypsum
Other sources of gypsum include phosphogypsum, citrogypsum and fluorogypsum, which are byproducts of different chemical manufacturing processes1. ... finely divided powder. This process is known as flue gas desulfurization (FGD), and the gypsum produced is known as FGD gypsum. The term FGD gypsum is the name most often used by generators of the ...
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Potential flue gas desulfurization gypsum utilization in griculture…
Gypsum comes in many different forms e.g., the gypsum used in soils is typically natural gypsum, which is mined or quarried (calcium sulfate dihydrate in dry powder form containing 80-98% product ...
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Production and resource utilization of flue gas desulfurized gypsum …
Flue gas desulfurized gypsum mainly comes from thermal power plants, smelters, and large-enterprise boilers, and contains industrial by-products produced through a wet desulfurization combustion process, where SO 2 gas and lime slurry react under strong oxidation conditions. The main component of this gypsum is calcium sulfate dihydrate, which also …
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Preparation of α-hemihydrate gypsum from phosphogypsum in …
The industrial application of PG is mainly focused on building gypsum (β-CaSO 4 ·0.5H 2 O) [5], α-hemihydrate gypsum (α-CaSO 4 ·0.5H 2 O, α-HH) [6], [7], cement retarder [8], sulfuric acid co-production cement [9], soil conditioner [10] and so on. Among which, the preparation of α-HH using PG is one of the most profitable approaches because α-HH is a high …
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Preparation of α-hemihydrate gypsum from phosphogypsum …
Preparation of α-hemihydrate gypsum (α-HH) from phosphogypsum (PG) by atmospheric hydrothermal method has a good application prospect due to the mild reaction conditions, the solution medium and ...
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Recycling flue gas desulfurisation gypsum and phosphogypsum for
This paper aims to explore the potential use of flue gas desulfurisation gypsum (FGDG) and phosphogypsum (PG) into cemented paste backfill (CPB). The mechanical strength of CPB and the binder paste properties (i.e., hydration heat, hydration evolution, acid erosion resistance, and leachability) were investigated experimentally.
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use something to judge whether phosphogypsum …
This paper aims to explore the potential use of flue gas desulfurisation gypsum (FGDG) and phosphogypsum (PG) into cemented paste backfill (CPB). The … WhatsApp: +86
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Use of Flue Gas Desulfurization Gypsum, Construction and …
This research aims to study the utilization of waste from power plants, construction and demolition, and agriculture by varying the ratios of flue-gas desulfurization (FGD) gypsum, construction and demolition waste (CDW), and oil palm trunks (OPT) in concrete production. This research used these as the raw materials for the production of concrete bricks of 15 × 15 × 15 …
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Recycling waste gypsum and calcium carbide slag for the …
The appropriate use of industrial solid waste is an effective method for alleviating environmental pollution. In this study, the potential of using desulfurized gypsum (DG), phosphogypsum (PG), gypsum dihydrate (G), and calcium carbide slag (CS) in the production of supersulfated cement (SSC) was investigated.
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CN102701619A
A technology making use of waste phosphogypsum to produce gypsum blocks comprises the steps of processing the waste phosphogypsum by a raw material room, and carrying out the sections of rotary drying and mixed pressing respectively after purification. The phosphogypsum is made into building gypsum packaged finished products after rotary drying, grinding and …
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Recycling flue gas desulfurisation gypsum and phosphogypsum for
The use of phosphogypsum waste in the production of building industry products, as well as for obtaining building gypsum is one of the most promising directions in the utilization of this mass ...
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Preparation of gypsum with high purity and whiteness from …
The purity and whiteness of the purified gypsum (CaSO4) significantly increased to 99% and 92%, respectively. The migration of impurities and the material balance of this …
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Utilization of Desulfurization Gypsum to Producing SO …
posing of desulfurization gypsum or Phosphogypsum to producing CaO and SO 2 is another promising utilization method for cement as well as sulfuric acid. The technologi-cal process includes drying, dehydration, calcining, cement firing, sulfur dioxide purification, sulfur dioxide absorption and so on. The main reactions are as follows:
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Desulfurization gypsum carbonation for CO2 sequestration …
Desulfurization gypsum is a kind of solid waste with CaSO 4 ‧2H 2 O as the main component produced in the process of limestone-based flue gas desulfurization. About 100 million tons of desulfurization gypsum was produced every year in China (Wang et al., 2020).On the one hand, it has a high content of Ca 2+ and is suitable for CO 2 sequestration. On the other hand, …
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A brief review on flue gas desulfurization gypsum recovery …
The most common application of FGDG is to directly use it in civil infrastructure materials. 11–14 The main component of FGDG is CaSO 4 ·2H 2 O with purity more than 90%. 15,16 Thus, it is an ideal material to replace natural gypsum. 17,18 Currently, about 70% of the total FGDG is used as raw material to produce wallboard, gypsum board, whitewashing, cement and concrete in the …
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Influence of crystal modifier on the preparation of α …
Crystal modifier is an important factor in preparation of α-hemihydrate gypsum (α-CaSO 4 ·0.5H 2 O) from phosphogypsum (PG). Here, α-CaSO 4 ·0.5H 2 O was prepared from PG using a semi-dry method. SEM, XRD, XPS were used to explore the effects of one or more crystal modifiers on crystal growth and mechanical properties after hydration and hardening of …
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Phosphogypsum Stacks
There is also an abundance of flue gas desulfurization gypsum produced as a by-product of coal-fired power plants. ... (EPA) banned the use of phosphogypsum. In 1992, this rule was modified to allow the use of phosphogypsum with an …
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Phosphogypsum decomposition desulfurization: Why difficult
Through designing, operating and simulating a bubbling fluidized bed PG decomposition desulfurization reaction system, this study clarifies the reasons for the PG desulfurization difficulty, and points out potential solutions.
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Gypsum | Use of Gypsum to reduce effluent and fertiliser nutrient
Gypsum has long been used as a soil conditioner and fertiliser but it is only recently that gypsum's potential for reducing agricultural emissions to waterways has been researched. Gypsum (CaSO 4.2H 2 O) can improve soil aggregation through calcium induced flocculation of particles and sulfate induced leaching of excess sodium. Such effects ...
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A Novel Process to Recover Gypsum from Phosphogypsum
In this study, we investigated a coarse phosphogypsum containing 49.63% SO3, 41.41% CaO, 10.68%, 4.47% SiO2, 1.28% P2O5, 0.11% F, CaSO4·2H2O purity of 80.65%, and whiteness of …
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Recycling flue gas desulfurisation gypsum and phosphogypsum …
As shown in Table 1, the main components of flue gas desulfurization gypsum are SO3, CaO, and bound water [34]. The main components of phosphogypsum and red gypsum are similar to those of FGDG, but they contain more impurities.…"
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Calcium sulfate whisker prepared by flue gas desulfurization gypsum…
Desulfurization gypsum is an industrial by-product formed by desulfurization of flue gas generated by power plants, petrochemical plants, steel plants and other industries [1].China is the world's largest coal producer and consumer [2].The large consumption of coal leads to huge stockpiles of desulfurization gypsum [3].The toxic elements in coal-fired flue gas may be …
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Phosphogypsum – An Industrial Byproduct with Value
Gypsum is especially beneficial to clay soils and is also used to treat sodic soils. As a source of gypsum, phosphogypsum can and does substitute natural gypsum as a soil amendment in many countries, including Australia, Brazil, and Spain, to name a few. Studies have even found that the application of phosphogypsum can increase crop yields in ...
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