Hydration and phase assemblage of limestone calcined

Table 3 summarises the mixture proportions used in this study. A fixed water-to-binder (w/b) ratio of 0.4/0.5 was used for all paste/mortar systems, respectively. The base LC 3-50 system was composed of 55 % OPC, 30 % calcined clay, and 15 % limestone on a mass basis, with 0.6 % added gypsum to maintain the sulfate balance.LC …

Effects of water-to-binder ratios (w/b) and superplasticizer …

Section snippets Materials. OPC Type I was used as the main binder. It contained approximately 5% of limestone powder as an add-on. Calcined kaolinitic clay supplied by The Society for Technology and Action for Rural Advancement (TARA), India, and limestone powder by Gulf Lime were used as the other constituents of the LC 3 …

High-quality gypsum binders based on synthetic calcium …

The production of anhydrite binder corresponded to reaction (3). (3) CaSO 4 ·2H 2 O = CaSO 4 + 2H 2 O. After firing, the anhydrite granules were ground together with activator additives, such as Portland cement, Ca(OH) 2, K 2 SO 4, which enabled to study the strength characteristics of the anhydrite binder. Surface morphology and …

ANHYDRITE BINDER CALCINED FROM …

Anhydrite binder calcined from phosphogypsum Ceramics – Silikáty 54 (2) 152-159 (2010) 155 was 9.1-9.2. The specific surface area was 1900 m2/kg. The cristabolite, the lisetite, the vaterite ...

[PDF] ANHYDRITE BINDER CALCINED FROM …

Published 2010. Materials Science. The phosphogypsum – dihydrate calcium sulphate is waste material of phosphoric acid production from the Kola apatites. The possibility of …

Analysis of Compressive Strength of Anhydrite Binder Using …

The obtained results showed that as the calcination temperature increased, the compressive strength of anhydrite binder decreased at its early age (up to 3 days) and …

Preparation and properties of II-anhydrite calcined

Calcination can reduce the soluble and co-crystal P 2 O 5 content of Phosphogypsum (PG). Ⅱ-anhydrite calcined from PG at 800 ºC had the best …

Preparation of anhydrite from phosphogypsum: Influence of phosphorus

The anhydrite binder calcined with the addition of 5% ground glass exposes the best physical and mechanical properties: the setting duration up to 13-38 min, the compressive strength of the dry ...

Clinker-Free Cement Based on Calcined Clay, Slag, …

A clinker-free and low-clinker cementitious binder approach was proposed based on portlandite, supplementary cementitious materials (SCMs), a sulfate source and an accelerator. The impact of ordinary Portland cement (OPC), portlandite, calcined clay and anhydrite on the strength of the seeded-CFC (with C-S-H seeding) was investigated.

ANHYDRITE BINDER CALCINED FROM PHOSPHOGYPSUM

The phosphogypsum – dihydrate calcium sulphate is waste material of phosphoric acid production from the Kola apatites. The possibility of applying lime neutralized phosphogypsum as a raw material for obtaining anhydrite binder was investigated in …

Mechanochemical syngenite as hydration accelerator for anhydrite …

A typical floor screed consists of a binder, ... Carbon footprint analysis of calcined gypsum production in the Czech Republic. J. Cleaner Prod. (2018) N. Lushnikova et al. ... Anhydrite has a much slower hydration rate and strength development than hemihydrate gypsum, and is commonly blended with cement, strong alkali or alkali …

Mechanical Activation on Phosphogypsum: Hydrosodalite …

Other research experiments were performed to determine the effect of calcined phosphogypsum on the strength of fly ash–lime binders. ... Anhydrite binder calcined from phosphogypsum. Ceram. Silik. 54(2), 152–159 (2010) Google Scholar Leškevičienė, V., Nizevičienė, D.: Influence of the setting activators on the physical …

Optimization of the activation process for natural anhydrite

It is known that the incorporation of gypsum in calcined gypsum plasters ... Anhydrite binder calcined from phosphogypsum, Ceram.-Silik. 54, 2, pp. 152-159 (2010) [25] Müller, M.; Lang, G.: New PCEs targeted selection of superplasticizers for various binder systems. ZKG International 69, Drymix Special, pp. 30-33 (2016)

Unlocking the potential of ordinary Portland cement with

We compared our model binder mix (70 wt% OPC, 7 wt% anhydrite, and 23 wt% limestone powder with 1.11 % solid of HyCon ... Calcined clay (CC) and limestone powder (LS) ...

Preparation of Anhydrite from Phosphogypsum: Influence …

The anhydrite binder calcined with the addition of 5% ground glass exposes the best physical and mechanical properties: the setting duration up to 13-38 min, the compressive strength of the dry ...

Influence of calcination temperature on hydration behavior, …

Delayed anhydrite II hydration was the cause of low strength and weathering resistance in plasters prepared with gypsum calcined at T ≥ 300 °C, but could, at least in part, be prevented by prolonging the curing process (i.e., avoiding premature drying of plasters) in order to facilitate the formation of gypsum binder. The only partial ...

Calcination parameters on phosphogypsum waste recycling

Calcined PG as binder can be an eco-friendly material. Abstract. The calcination at low temperatures transforms phosphogypsum (PG) waste in a material …

Preparation and properties of II-anhydrite calcined

The particle size of anhydrite calcined at 650 ºC-750 ºC decreased with calcination temperature, resulting in closer packing [37]. Thus, the water requirement decreased and the rheological properties of PG paste were improved. However, all the characteristic particle sizes of anhydrite calcined at 800 ºC were larger than those of …

Composition of calcined mixtures. | Download Table

Anhydrite cement is widely utilized in the construction industry in many countries. It is gypsum calcined at high temperatures (600-700 °C) [14].Alum plaster is a product obtained by mixing ...

Influence of phosphatic impurities on the anhydrite

The anhydrite binder calcined with the addition of 5% ground glass exposes the best physical and mechanical properties: the setting duration up to 13-38 min, the compressive strength of the dry ...

Application of lime neutralised phosphogypsum in …

Double-sided tuning effects of lactic acid on the hydration, microstructure and strength of supersulfated cement. In this study, hemihydrate gypsum was employed to produce supersulfated cement (SSC), and lactic acid was used to address the poor workability induced. The results indicated that lactic acid….

Alkali-activated binders based on ground granulated blast furnace slag

No gypsum, anhydrite or bassanite peaks were observed, proving the complete dissolution of PG upon mixing. In other words, a hydraulic binder is created. The phases determined are ettringite, portlandite, thenardite and merwinite, revealing the action of PG on hydration. ... Anhydrite binder calcined from phosphogypsum. Ceram. – …

Durability of phosphogypsum based water-resistant anhydrite binder

Durability of phosphogypsum based water-resistant anhydrite binder. Author links open overlay panel Manjit Singh, Mridul Garg, S.S. Rehsi. Show more. ... Singh et al. (1990) calcined PG at 800 °C for 4 h. Rashad (2015) calcined PG at 850 °C for 2 h. Leškevičiene and Nizevičiene (2014) calcined PG at 800 and 900 °C for 30 min. Smadi …

Analysis of Compressive Strength of Anhydrite Binder …

the production of a high-performance anhydrite binder [28,29]. The FGD gypsum calcined at 650 C for 4 h was used in the mixture of Portland cement to produce self-levelling floors [30]. Anhydrite cement was obtained from FGD gypsum, which was burnt together with activators, such as glass and cupola dust, at 800 and 900 C [31].

Study on anhydrite plaster from waste phosphogypsum for …

The paper deals with an investigation about the production of high strength plaster from the waste phosphogypsum and its use in making flooring tiles. To achieve this objective, phosphogypsum was calcined at 900–1000 °C to anhydrite which was mixed with suitable chemical activators (alkali/alkaline earth hydroxides, sulphates, …

(PDF) Reducing clinker factor in limestone calcined clay-slag …

The combination of calcined clay with other supplementary cementitious materials (LC3+), including microsilica, slag (GGBFS), and fly ash, was investigated. The impact of anhydrite content and ...

Dehydration behaviour and impurity change of

In order to obtain calcined gypsum, PG was heated in an electric oven at 150 °C for 2 h [24], and Garg et al. [25] prepared β-hemihydrate gypsum at 150–160 °C for 4 h. ... Anhydrite binder calcined from phosphogypsum. Ceramics Silikaty, 54 (2010), pp. 152-159. Google Scholar [21]

Research on the Influence of Gypsum and Anhydrite Stone …

Gypsum (CaSO 4 2H 2 O) and anhydrite (CaSO 4) are the most common sulfate minerals.The predominant part of gypsum and anhydrite is used as raw materials for the production of gypsum binders (construction gypsum) and additives in various types of cements, to a lesser extent–for the production of hard-burnt, high-strength, molding …

Analysis of Compressive Strength of Anhydrite Binder Using …

Flue gas desulfurization gypsum (FGD gypsum) is obtained from the desulphurization of combustion gases in fossil fuel power plants. FGD gypsum can be used to produce anhydrite binder. This research is devoted to the investigation of the influence of the calcination temperature of FGD gypsum, the activators K2SO4 and Na2SO4, and …

ANHYDRITE BINDER CALCINED FROM PHOSPHOGYPSUM

The phosphogypsum – dihydrate calcium sulphate is waste material of phosphoric acid production from the Kola apatites. The possibility of applying lime neutralized phosphogypsum as a raw material for obtaining anhydrite binder was …

SEM microphotographs of anhydrite binder calcined at …

Ceramics – Silikáty 54 (2) 152-159 (2010) from publication: Anhydrite binder calcined from phosphogypsum | The phosphogypsum – dihydrate calcium sulphate is waste material of phosphoric acid ...

Morphology, crystal structure and hydration of calcined and …

The effects of calcination and modification on the morphology (shapes and textures) and crystal structure of anhydrite powders were studied. The results show that, calcination at 100°C causes anhydrite to disintegrate into smaller crystals, accompanied by a slight increase in d-spacing. Without calcination and modification, the solidification time …

Recycling of phosphogypsum to prepare gypsum plaster: …

Then PG was calcined at 150 °C, 200 °C, 300 °C, 400 °C, 500 °C, 600 °C, 700 °C, and 800 °C for 3 h in a muffle furnace to obtain hemihydrate or anhydrite. After the calcination, the calcined PG (CPG) was ground to a specific surface area (420 ± 20) m 2 /kg, and the particle size distribution of CPG was shown in Fig. 2 .

Study on anhydrite plaster from waste phosphogypsum for …

Experiments were performed to investigate the properties of fly ash-calcined phosphogypsum (PG) cementitous materials with PG different thermally treated, including ... This research is devoted to modification of physical and mechanical properties and structure of a binder based on natural anhydrite. A sedimentary rock siltstone was added into ...

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