Evaluation of the reactivity of artificial mixtures of Portland cement clinker obtained by flame spray pyrolysis

Andrés Felipe Pinto; Jorge Iván Tobón; Natalia Betancur-Granados; Oscar Jaime Restrepo-Baena

doi:10.13005/msri/160204

Evaluation of the reactivity of artificial mixtures of Portland cement clinker obtained by flame spray pyrolysis

Material Science Research India ◽

10.13005/msri/160204 ◽

2019 ◽

Vol 16 (2) ◽

pp. 110-117 ◽

Cited By ~ 1

Author(s):

Andrés Felipe Pinto ◽

Jorge Iván Tobón ◽

Natalia Betancur-Granados ◽

Oscar Jaime Restrepo-Baena

Keyword(s):

Portland Cement ◽

Spray Pyrolysis ◽

Cement Clinker ◽

Flame Spray Pyrolysis ◽

Mechanical Resistance ◽

Flame Spray ◽

X Ray Diffraction ◽

Fundamental Properties ◽

Portland Cement Clinker ◽

Reaction With Water

The Portland cement clinker consists of 95% calcium oxide, silicon, aluminium and iron and 5% impurities of magnesium, sodium, potassium, titanium, sulfur, phosphorus and manganese. From the combination of two or more of the main oxides, the constituents of the white clinker are formed, corresponding to alite(3CaO.SiO2 or C3S), belite (2CaO.SiO2 or C2S) and celite (Ca3Al2O6 or C3A), which give cement its characteristic properties. The fundamental properties of cement are its mechanical resistance, chemical resistance, the speed of reaction with water and the heat given off in hydration. In this work, the reactivity of an artificial mixture of white clinker, formed from alite, belite and celite prepared by flame spray pyrolysis was evaluated. The phases were characterized by X-ray diffraction, scanning electron microscopy and microcalorimetry, to evaluate their formation and reactivity. The characterization showed that during the synthesis of belite, a greater amount of the polymorph alpha was produced, with some impurities. On the other hand, the synthesis of celite allowed the production of the polymorph CII. The reactivity was evaluated by microcalorimetry.

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Effects of Calcination Conditions on the Formation and Hydration Performance of High-Alite White Portland Cement Clinker

Materials ◽

10.3390/ma13030494 ◽

2020 ◽

Vol 13 (3) ◽

pp. 494 ◽

Cited By ~ 1

Author(s):

Lei Huang ◽

Geling Cheng ◽

Shaowen Huang

Keyword(s):

Portland Cement ◽

Mineral Composition ◽

Sintering Temperature ◽

Cement Clinker ◽

X Ray Diffraction ◽

Scanning Calorimetry ◽

Free Lime ◽

Sintering Time ◽

Portland Cement Clinker ◽

White Portland Cement

The purpose of this study was to evaluate the effects of sintering temperature and sintering time on mineral composition of high-alite white Portland cement clinker and hydration activity of the clinker. Effects of sintering temperature and sintering time on clinker mineral composition, C3S polymorph and size and hydration heat release rate were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), differential scanning calorimetry&Thermogravimetric Analysis (DSC-TG) and isothermal heat-conduction calorimetry. Results shown that, with the increase of sintering temperature (1450–1525 °C) and sintering time (60–240 min), free lime (f-CaO) in clinker decreased, C3S grain size increased, and C3S crystal type changed from T3 to M type and R type, which exhibits higher symmetry. The hydration activity of different C3S crystals ranged from high to low as follows: T3→M1→M3→R@.

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Effects of CaF2 on the Formation Kinetics of Portland Cement Clinker

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.306-307.966 ◽

2011 ◽

Vol 306-307 ◽

pp. 966-969

Author(s):

Chun Fang Wang ◽

Zong Hui Zhou ◽

Cai Xia Liu ◽

Xin Cheng

Keyword(s):

Portland Cement ◽

Formation Rate ◽

Reaction Rate Constant ◽

Cement Clinker ◽

X Ray Diffraction ◽

Free Lime ◽

X Ray ◽

Formation Kinetics ◽

Portland Cement Clinker ◽

Kinetics Of

Through testing the amount of the free lime and the Loss ignition, the clinker formation rate, the reaction-rate constant (K) and the activation energy (Ea) were calculated according to the Gentling equation and Arrhenius equation. The effects of CaF2on the formation kinetics of Portland cement clinker were investigated by analyzing theKandEa. X-ray diffraction (XRD) and scanning electron Microscope (SEM) were used to characterize the phase composition and the morphology of the resulting samples. The results show that the silicate minerals formation is promoted when a proper amount of CaF2is doped into the raw meal. TheKincreased from 0.7450 ×10-5s-1to 7.1588 ×10-5s-1and theEadecreased from 386 kJ/mol to 122 kJ/mol when the amount of CaF2increased from 0.0% to 2.0% in mass. However, the results were reversed at the amount of CaF2exceeding 2%.

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Luminescent properties of Y2O3:Eu3+ nanophosphor prepared from urea added precursor using flame spray pyrolysis

Journal of Materials Research ◽

10.1557/jmr.2009.0319 ◽

2009 ◽

Vol 24 (8) ◽

pp. 2584-2588 ◽

Cited By ~ 5

Author(s):

Jae Seok Lee ◽

Se Jin Kim ◽

Tae Kon Kim ◽

Rajiv K. Singh ◽

Madhav B. Ranade

Keyword(s):

Electron Microscopy ◽

Spray Pyrolysis ◽

Red Light ◽

Luminescent Properties ◽

Flame Spray Pyrolysis ◽

Cubic Phase ◽

Flame Spray ◽

X Ray Diffraction ◽

Synthesis Conditions ◽

Transmission Electron

Y2O3:Eu3+ nanophosphor was synthesized by flame spray pyrolysis (FSP) from urea added nitrate based liquid precursor. In this study, urea serves as fuel and subsequently provides additional heat in the flame zone during the synthesis of phosphor particles. The end product shows cubic phase Y2O3:Eu3+ nanophosphor successfully prepared by FSP without heat treatment. The influence of synthesis conditions such as different mol of urea and nitrate source materials in aqueous solution, and doping concentration on luminescent properties, were investigated. The characteristics of nanophosphor such as crystallinity and morphology under various experiments of conditions were carried out by x-ray diffraction (XRD) and field emission-scanning electron microscopy (FE-SEM). The particle size of product was found to be in the range of 20–30 nm from transmission electron microscopy (TEM). In photoluminescence (PL) properties, Y2O3:Eu3+ nanophosphor emitted red light with a peak wavelength of 609 nm when excited with 398 nm wavelength photons.

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Effect of Phosphogypsum on the Clinkerization Temperature of Portland Cement Clincker

Materials Science Forum ◽

10.4028/www.scientific.net/msf.730-732.94 ◽

2012 ◽

Vol 730-732 ◽

pp. 94-99 ◽

Cited By ~ 1

Author(s):

Maria Margarida Rolim Augusto Lima ◽

L.F.C. Braz ◽

Regina da Conceição Corredeira Monteiro ◽

J.P. Veiga

Keyword(s):

Compressive Strength ◽

Portland Cement ◽

Raw Materials ◽

Cement Clinker ◽

X Ray Diffraction ◽

X Ray ◽

Portland Cement Clinker ◽

Alternative Material ◽

Heating Up ◽

Mineralogical Compositions

Phosphogypsum (PG) is a pollutant residue resulting from the production of phosphoric acid in the phosphated fertilizers industry. About 180 millions of tons of PG are generated worldwide per year, which originates storage problems because of the environmental restrictions and the high costs of storage spaces. Taking into account the mineralizer properties of PG it has been studied a way to valorize this residue as an alternative material in the production of Portland cement clinker. The PG and the raw-materials (limestone, marl, sand and iron oxide) were chemical, mineralogical and thermally characterized by X-ray fluorescence (XRF), X-ray diffraction (XRD) and differential thermal analysis and termogravimetric analysis (DTA/TGA). After milling, the phosphogypsum was mixed with the raw-materials in different amounts up to 10% weight. The raw mixtures were submitted to two types of firing schedules, heating up to 1500°C without any holding time or heating up to 1350°C and holding for 20 minutes. After firing, the clinkers were analyzed by optical microscopy, milled and characterized in terms of chemical and mineralogical compositions. The clinkers were used to produce cement mortar according to NP EN 196-1 standard. The resultant test specimens were mechanically tested at 2 and 28 days according to the same standard. The obtained results show a reduction of about 140°C in the clinkerization temperature, when a raw mixture with 5% phosphogypsum was used. Standard clinkers, without phosphogypsum addition, which were fired at 1500°C, originated test specimens with a compressive strength of 48.1MPa at 28 days. Test specimens produced with clinker containing 5% phosphogypsum present higher compressive strength values at 28 days, being 55.1MPa for clinkers produced at 1500°C, and 49.4 MPa for clinkers produced at 1350°C.

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Use of Design of Experiments (DoE) to Model the Sulphate Agent Amount of (Ultra)Finely Ground and Fast Hardening Portland Cement Clinker

Materials ◽

10.3390/ma14195573 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5573

Author(s):

Tim Schade ◽

Bernhard Middendorf

Keyword(s):

Design Of Experiments ◽

Portland Cement ◽

Calcium Sulphate ◽

Cement Clinker ◽

X Ray Diffraction ◽

Resource Saving ◽

X Ray ◽

Portland Cement Clinker ◽

Material Sciences

This paper presents a model to calculate the sulphate agent amount and sulphate agent ratio for fine grounded and fast hardening Portland cement clinker. Despite sufficient knowledge about the influence of calcium sulphate on the hydration process of cement, the sulphate agent amount is mostly adjusted empirically. As a result, often a wide and unfeasible experimental matrix has to be tested. In this work, Design of Experiments (DoE) was used in combination with in-situ X-ray diffraction (XRD) tests to accurately adjust the sulphate agent of different finely ground cement by calculation. With only 42 tests, it was possible to analyse in total the influence of the sulphate agent, the grinding fineness and the use of C-S-H-seeds for the use in fast-hardening Portland cement-based systems. In addition, it was found that a hemihydrate to anhydrite content of 25/75 leads to a stabilisation of the hydrated system in the first 24 h of hydration. A model for the optimisation of the sulphate agent composition in dependency of the cement fineness could be determined. Furthermore, it was shown that the DoE also provides optimal results in material sciences in a resource-saving way.

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Preparation of Portland Cement with Pumice

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.99-100.733 ◽

2011 ◽

Vol 99-100 ◽

pp. 733-738

Author(s):

Shi Cai Cui ◽

Xing Jun Lv ◽

Jing Liu

Keyword(s):

Mechanical Property ◽

Electron Microscope ◽

Scanning Electron Microscope ◽

Portland Cement ◽

Cement Clinker ◽

X Ray Diffraction ◽

Calcine Temperature ◽

X Ray ◽

Portland Cement Clinker ◽

Scanning Electron

The portland cement clinker was successfully produced using pumice as the principal materials. Effects of different calcine temperature on cement clinker were studied. Phase compositions of clinker were confirmed by combining the phase diagram with X-ray diffraction. Microstructures of clinker were analyzed by scanning electron microscope. From the result of mechanical property showed that the compression strength of clinker can be reached 35MPa. The result of scanning electron microscope showed that the main hydrating products were CSH gels, AFt and CH crystals, the morphology of which were normal. With the prolongation of hydrating age, the hydrating products were richer and the cement paste was densified.

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