Effect of Modified Phosphogypsum on Properties of Cement Mortar
Abstract. The resource utilization of phosphogypsum (PG) can reduce the consumption of resources, turn waste into valuables, turn damage into profit, and form a green recycling economy of "resources-products-regenerated resources." The article, combined with the comprehensive utilization of PG, analyzes the existing problems. Using lime neutralization to …
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Effect of different retarders on setting time and mechanical …
The optimization of mechanical properties and regulation in setting time of beta-hemihydrate phosphogypsum (β-HPG) are the key to its utilization in building materials. Calcium sulfoaluminate cement (SAC) can significantly enhance the mechanical properties of β-HPG to form a gypsum-based-composite binder, but have little effect on regulating the setting time.
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Setting Time Optimization of Excessive-Sulfate Phosphogypsum …
The accumulation of phosphogypsum (PG) has become a significant environmental and economic challenge, making PG reuse an urgent concern. This study aims to explore the potential of combining PG with steel slag (SS), ground granulated blast-furnace slag (GGBS), and cement clinker (CC) to create excessive-sulfate phosphogypsum slag cement …
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Purification of South African phosphogypsum for use …
We have investigated a method to remove the phosphorus impurities present in South African phosphogypsums, and found that the combination of a thermal and a sulphuric acid treatment was successful...
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Utilization of solidified phosphogypsum as Portland cement …
In this paper, we describe how two types of stabilizer are prepared to stabilize the gypsum in order to ensure that the PG may be fed in the cement mill stably. Some competents …
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Modification of phosphogypsum using circulating fluidized bed fly …
DOI: 10.1016/j.conbuildmat.2022.127630 Corpus ID: 248445855; Modification of phosphogypsum using circulating fluidized bed fly ash and carbide slag for use as cement retarder @article{Li2022ModificationOP, title={Modification of phosphogypsum using circulating fluidized bed fly ash and carbide slag for use as cement retarder}, author={Bei Xing Li and Longzhi Li …
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Research on the Performance of Phosphorus Building Gypsum
No calcium alumina crystals were found in the graph; For experimental group 10, the addition of 1.0% high efficiency water reducing agent, 0.3% redispersible emulsion powder, 0.3% cellulose ether and 0.1% protein-based retarder to the phosphogypsum-based lightweight concrete material reduced the particle size of the material's microscopic ...
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Retardation mechanism of phosphogypsum in phosphogypsum …
Using phosphogypsum-based excess-sulfate cement (PESC) for the preparation of super retarding materials. PESC can achieve initial setting for 86 hours and final setting for …
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Recycling of phosphogypsum to prepare gypsum plaster: Effect of
Approximately 4–5 tons of PG are generated for every ton of P 2 O 5 produced. According to statistics, the worldwide PG generation exceeded 280 Mt/yr [4], of which 75 Mt/yr were generated in China with a total stockpile of more than 600 Mt [5].Up to now, only 15% of the worldwide PG were recycled as cement retarder [[6], [7], [8]], road filling materials [9, 10], soil …
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Utilization of solidified phosphogypsum as Portland cement …
Abstract The utilization of the phosphogypsum (PG) as cement retarder is both an economical and an ecological approach to treat this solid waste. Cement using raw PG as retarder has two …
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Purification of South African phosphogypsum for use …
The cement test proved that treated PG could partially replace natural gypsum as a retarder.Keywords: phosphogypsum treatment, phosphorus pentoxide removal, calcium sulfate transition phase ...
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THERMAL TREATMENT OF PHOSPHOGYPSUM AS A SET RETARDER …
Phosphogypsum (PG), the by-product of phosphoric acid industry, comprises of calcium sulfate dihydrate, and other contaminants which restricts the industrial use of phosphogypsum in cement industry as a set retarder. Remedial thermal treatment of phosphogypsum as a set retarder for Portland cement production is investigated in this …
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PURIFICATION OF PHOSPHOGYPSUM FOR USE AS CEMENT RETARDER …
The cement test proved that treated PG could partially replace natural gypsum as a retarder.Keywords: phosphogypsum treatment, phosphorus pentoxide removal, calcium sulfate transition phase ...
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Valorization of phosphogypsum in cement-based materials: Limits …
Thus, this paper aims to analyze the soluble phosphate, fluoride, and pH effects of Brazilian phosphogypsum used as a setting retarder on the hydration of Portland cement.
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Investigation on Utilization of Phosphogypsum as a Partial …
in concrete. Phosphogypsum has been used with 3%, 7% and 10% percentages as partially replacement of cement. Results ... can be utilized as a retarder instead Portland cement. The best compressive strength after 28 days was appeared in specimens with 3% PG. Bhadauria and Thakare (2006) [6] concluded that ...
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THERMAL TREATMENT OF PHOSPHOGYPSUM AS A SET …
Remedial thermal treatment of phosphogypsum as a set retarder for Portland cement production is investigated in this research work. The SEM-EDS analysis of the raw …
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Retardation mechanism of phosphogypsum in phosphogypsum …
Using phosphogypsum-based excess-sulfate cement (PESC) for the preparation of super retarding materials. ... the effect of various chemical and physical treatments of a South African phosphogypsum to render it suitable as a set retarder for cement. Cem. Concr. Res., 33 (2003), pp. 1223-1227. View PDF View article View in Scopus Google Scholar
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Hydration analysis of phosphogypsum cementitious materials
Phosphogypsum is restricted as a building material because of its poor water resistance. In this study, phosphorus building gypsum, cement, and lime were used as the main materials, and water reducer and retarder were used as additives to prepare phosphorus gypsum cementitious materials under low water–cement ratio. Concurrently, the mechanical properties …
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Modified phosphogypsum cement retarder
The invention relates to a modified phosphogypsum cement retarder which is prepared by the following steps: uniformly stirring 3-10 parts by weight of carbide ash and 90-98 parts by weight of dihydrate gypsum, balling, and modifying by drying, thereby obtaining the modified phosphogypsum cement retarder, wherein the carbide ash is aired, baked and ground into …
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Phosphogypsum-Based Ultra-Low Basicity Cementing Material
Sulphoaluminate cement minerals mainly include Ca 4 (Al 6 O 12)SO 4, C 2 S, SiO 2, Al 2 O 3 and so on. They have short setting times and high early strengths. The 3 d compressive strength of sulphoaluminate cement reaches 42.5 Mpa, and its performance test results is showed in Table 2.Phosphogypsum consists of a large amount of CaSO 4 ·2H 2 O and a small amount of …
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Modification of phosphogypsum using circulating fluidized bed fly ash and carbide slag for use as cement retarder
Utilization of weathered phosphogypsum as set retarder in …
In this study, usability of PG residues obtained from BAGFAŞ in Turkey as a set retarder in Portland cement was investigated. Every year, such residues occupying …
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Valorization of phosphogypsum in cement-based materials: Limits …
Phosphogypsum-based cement is prone to undergo moisture, due to the ease of solubilization in the presence of water. Therefore, its use is restricted to indoor environments. ... And then, the utilization of PG including cement retarder, building materials, cement raw materials, concrete raw materials, cementitious materials, and fillers and ...
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Effect of soluble phosphate, fluoride, and pH in Brazilian
Thus, this paper aims to analyze the soluble phosphate, fluoride, and pH effects of Brazilian phosphogypsum used as a setting retarder on the hydration of Portland cement. The influence of pH, a soluble phosphate, and soluble fluoride on the optimum cement sulfate content, setting time, compressive strength, and cement hydration products were ...
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(573f) Valorizing Phosphogypsum As a Set Retarder in Portland Cement
Phosphogypsum is a by-product in phosphate fertilizers and phosphoric acid industries. It is valorized as a set retarder in Portland cement replacing the gypsum rocks. In this industry, influence of phosphogypsum contents on concrete and …
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Modification of recycled cement with phosphogypsum and GGBS
This paper presents the rehydration performance of binary binders made with dehydrated cement paste (DCP) and phosphogypsum (GP). ... from residue areas as set retarder in Portland cement was ...
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Development and optimization of phosphogypsum-based geopolymer cement
The PBG cement was prepared using phosphogypsum waste, and the 28-day compressive strength of the cement can exceed 60 MPa. ... When mixed with Portland cement, PG is a good cement retarder, and a binder can be made by mixing PG with cement clinker [14], [15]. However, such applications are not nearly enough to consume the huge amount of PG ...
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Effect of soluble phosphate, fluoride, and pH in Brazilian
DOI: 10.1016/j.cscm.2022.e01413 Corpus ID: 251650878; Effect of soluble phosphate, fluoride, and pH in Brazilian phosphogypsum used as setting retarder on Portland cement hydration
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Utilization of phosphogypsum in portland cement industry
When added to the cement plant rawmix, the phosphogypsum acted both as a mineralizer for clinker and a set retarder for cement made from this clinker. Vol. 7, No. 5 543 PHOSPHOGYPSUM, CLINKER, STRENGTH, RETARDATION Due perhaps to the lower temperature of clinker formation, the clinker contain- ing phosphogypsum produced a cement …
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Investigation of cement retarder made of chemically pretreated
Phosphogypsum was chemically pretreated by using lime solution,ammonium hydroxide,and aqueous citric acid solution,respectively.The content of impurities of purified phosphogypsum was examined and its DTA was performed.The setting time and strength of the cement produced with purified phosphogypsum were tested.Results showed that the phosphogypsum pretreated by …
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EFFECT OF CALCINED PHOSPHOGYPSUM IN PORTLAND POZZOLANA CEMENT CONCRETE
Utilization of solidified phosphogypsum as Portland cement retarder. Weiguo Shen Gejin Gan Rui Dong Hu Chen Yu Tan Mingkai Zhou. Environmental Science, Materials Science. 2012; The utilization of the phosphogypsum (PG) as cement retarder is both an economical and an ecological approach to treat this solid waste.
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