scholarly journals The Effect of Fluoride and Iron Content on the Clinkering of Alite-Ye’elimite-Ferrite (AYF) Cement Systems

2021 ◽  
Vol 7 ◽  
Author(s):  
Visa Isteri ◽  
Katja Ohenoja ◽  
Theodore Hanein ◽  
Hajime Kinoshita ◽  
Mirja Illikainen ◽  
...  

Alite–ye’elimite–ferrite (AYF) cement is a more sustainable alternative to Portland cement (PC) that may offer improved mechanical, rheological, and chemical performance. Using traditional raw materials and conventional clinker processing conditions, alite (C3S) and ye’elimite (C4A3$), the major phases in PC and calcium sulfoaluminate (CSA) cements, respectively, cannot be coproduced. The typical formation temperature in the kiln for alite is >1350°C, but ye’elimite normally breaks down above 1300°C. However, with careful composition control and in the presence of fluoride, alite can be mineralized and formed at lower temperatures, thus enabling the production of AYF clinkers in a single stage. In this study, the production of AYF cement clinkers with different chemical compositions is attempted at 1250°C. The sensitivity of the fluoride content is initially assessed with a fixed target clinker composition to determine the optimal requirements. The effect of altering the target ferrite (C4AF) and alite (C3S) contents is also assessed followed by the effect of altering the target C4AF and C4A3$ contents. It is shown that AYF clinkers can be produced in a single stage through the careful control of the fluoride content in the mix; however, the formation/persistence of belite and mayenite could not be avoided under the conditions tested. It is also shown that ∼10 wt% ferrite in the target composition provides sufficient AYF clinker burnability and the amount of fluoride needs to be controlled to avoid stabilization of mayenite.

2016 ◽  
Vol 192 ◽  
pp. 113-124 ◽  
Author(s):  
Liya Zheng ◽  
Thomas P. Hills ◽  
Paul Fennell

Cement manufacture is one of the major contributors (7–10%) to global anthropogenic CO2 emissions. Carbon capture and storage (CCS) has been identified as a vital technology for decarbonising the sector. Oxy-fuel combustion, involving burning fuel in a mixture of recycled CO2 and pure O2 instead of air, makes CO2 capture much easier. Since it combines a theoretically lower energy penalty with an increase in production, it is attractive as a CCS technology in cement plants. However, it is necessary to demonstrate that changes in the clinkering atmosphere do not reduce the quality of the clinker produced. Clinkers were successfully produced in an oxy-fuel atmosphere using only pure oxides as raw materials as well as a mixture of oxides and clay. Then, CEM I cements were prepared by the addition of 5 wt% gypsum to the clinkers. Quantitative XRD and XRF were used to obtain the phase and elemental compositions of the clinkers. The particle size distribution and compressive strength of the cements at 3, 7, 14, and 28 days' ages were tested, and the effect of the particle size distribution on the compressive strength was investigated. Additionally, the compressive strength of the cements produced in oxy-fuel atmospheres was compared with those of the cement produced in air and commercially available CEMEX CEM I. The results show that good-quality cement can be successfully produced in an oxy-fuel atmosphere and it has similar phase and chemical compositions to CEM I. Additionally, it has a comparable compressive strength to the cement produced in air and to commercially available CEMEX CEM I.


2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Darfizzi Derawi ◽  
Bashar Mudhaffar Abdullah ◽  
Hasniza Zaman Huri ◽  
Rahimi M. Yusop ◽  
Jumat Salimon ◽  
...  

Palm olein (POo) is widely produced as edible oil in tropical countries. POois considered as renewable raw material for the new industrial and pharmaceutical products synthesis based on its characterization. Palm olein was good on its viscosity index, oxidative stability, and flash and fire point. POocontained unsaturated triacylglycerols (TAGs): POO (33.3%); POP (29.6%) which plays an important role in chemical modification process to produce new industrial products. The double bond was detected on1H-NMR (5.3 ppm) and13C-NMR (130 ppm) spectra. The chemical compositions of POowere tested by using high performance liquid chromatography (HPLC) and gas chromatography (GC) techniques. This unsaturated oil is potentially to be used as renewable raw materials in chemical modification process to synthesise polyols, polyurethane, and biolubricant for industrial and pharmaceutical products application.


Foods ◽  
2018 ◽  
Vol 7 (11) ◽  
pp. 175 ◽  
Author(s):  
Tibet Tangpao ◽  
Hsiao-Hang Chung ◽  
Sarana Sommano

The research objectives of this study are to analyse the volatile compositions of different basil types available in Thai markets and to descriptively determine their aromatic qualities. Essential oils were hydro-distillated from fresh leaves of two Holy basil (Ocimum sanctum) varieties namely, white and red and other basil species, including Tree basil (O. gratissimum), Thai basil (O. basilicum var. thyrsiflorum), and Lemon basil (O. citriodorum). Oil physiochemical characteristics and volatile chromatograms from Gas Chromatography–Mass Spectrometry (GC-MS) were used to qualitatively and quantitatively describe the chemical compositions. Estragole, eugenol, and methyl eugenol were among the major volatiles found in the essential oils of these basil types. Classification by Principal Component Analysis (PCA) advised that these Ocimum spp. samples are grouped based on either the distinctive anise, citrus aroma (estragole, geranial and neral), or spice-like aroma (methyl eugenol, β-caryophyllene, and α-cubebene). The essential oils were also used for descriptive sensorial determination by five semi-trained panellists, using the following developed terms: anise, citrus, herb, spice, sweet, and woody. The panellists were able to differentiate essential oils of white Holy basil from red Holy basil based on the intensity of the anisic attribute, while the anise and citrus scents were detected as dominant in the Lemon basil, Tree basil, and Thai basil essential oils. The overall benefit from this research was the elucidation of aromatic qualities from Thai common Ocimum species in order to assess their potential as the raw materials for new food products.


2014 ◽  
Vol 32 (5) ◽  
pp. 397-405
Author(s):  
Md. Obaidul Haque ◽  
Ahmed Sharif

Informal incineration or open pit burning of waste materials is a common practice in the peripheral area of Dhaka, one of the fastest growing mega-cities in the world. This study deals with the effect of open pit burned (i.e. open burned) household waste bottom ash on fired clay bricks. Between 0 to 50% (by weight) of open pit burned household waste bottom ash was mixed with clay to make bricks. The molded specimens were air-dried at room temperature for 24 h and then oven dried at 100 °C for another 24 h to remove the water. The raw bricks were fired in a muffle furnace to a designated temperature (800, 900 and 1000 °C, respectively). The firing behaviour (mechanical strength, water absorption and shrinkage) was determined. The microstructures, phase compositions and leachates were evaluated for bricks manufactured at different firing temperatures. These results demonstrate that open pit burned ash can be recycled in clay bricks. This study also presents physical observations of the incinerated ash particles and determination of the chemical compositions of the raw materials by wet analysis. Open pit burned ash can be introduced easily into bricks up to 20% wt. The concentrations of hazardous components in the leachates were below the standard threshold for inert waste category landfill and their environmental risk during their use-life step can be considered negligible.


2010 ◽  
Vol 105-106 ◽  
pp. 778-781
Author(s):  
Yin Feng Xia ◽  
Zhao Hui Huang ◽  
Jia Zheng Yuan ◽  
Lin Jun Wang ◽  
Jie Hua Xie

Crystalline glaze is a kind of art glaze with excellent decorative performance, the existing crystalline glaze mainly willemite crystalline glaze, systems on a single track. In this paper, the use of crystalline glaze raw materials for glass, ZnO and coke gemstones, CuO as coloring agents, using ortho- gonal to determine the formula, this paper researched that added TiO2 to the willemite crystalline glaze crystal phase composition as well as the amount of TiO2 and processing conditions on the preparation of crystalline glaze crystal flower morphology impact. The results show that under the conditions of 1250°C melting 1130°C crystallization process crystal spontaneous growth in crystalline glaze can be able to cover the entire glazed, shape of crystals was feathered, cross growth, the number of crystal increased with crystallization temperature, glaze was smooth and shiny sense. XRD and optical microscopy analysis showed that the precipitation of crystals was the long column of rutile, crystal distributed equality, under a polarizing microscope in purple, green and black, with strong aesthetic values.


Author(s):  
Л. Сулейманова ◽  
Lyudmila Suleymanova ◽  
А. Кочерженко ◽  
A. Kocherzhenko ◽  
И. Рябчевский ◽  
...  

Currently in Russia, great importance is attached to actual issues of energy saving and energy efficiency in construction. Valid regulations require addressing issues related to improving the energy efficiency of buildings. The development and manufacture of new types of effective thermal insulation materials is one of the ways to solve assigned tasks. The use of industrial waste from mining and processing plants as a filler for polyurethane foam is considered in this paper. Samples from the filtration field of the tailings of Stoilensky GOK from various sites are taken as the studied raw materials; their granulometric, chemical compositions and harmonic diameters of the filler particles are determined. According to the calculation results, the dependence of the foaming coefficient on the average harmonic diameter of the filler is determined. The experiment-planning matrix is developed; according to its results, mathematical models are constructed for the dependence of the foaming coefficient of laboratory samples of polyurethane foam filled with tails. Three tail zones based on the results of sampling are considered. Analyzing the obtained results, a quantitative and qualitative assessment of the influence of each factor individually and their combination on the change in the “composition - properties” system is derived.


Clay Minerals ◽  
2010 ◽  
Vol 45 (3) ◽  
pp. 353-370 ◽  
Author(s):  
R. Marques ◽  
A. Jorge ◽  
D. Franco ◽  
M. I. Dias ◽  
M. I. Prudêncio

AbstractMineralogical and chemical compositions of residual and sedimentary clays (bulk and <2 μm fraction) from the Nelas region (schist, aplite-pegmatites, granites and Tertiary sediments from both Mondego River margins), Portugal, were studied, aiming to establish indicators for raw materials in ancient ceramic provenance studies. The mineralogy of bulk material does not provide a clear distinction between samples. Among clay minerals, kaolinite dominates, except in the aplite-pegmatites where illite prevails. Smectite was only found in sediments of the left river bank.A more successful result was the geochemical differentiation of clay types. The weathered schist presents greater enrichment in Cr, whereas the clay fraction of aplite-pegmatites shows enrichment in all the chemical elements studied. The sediments and weathered granites are not easy to differentiate; the best geochemical indicators are U (lower contents in clay-size fraction of sediments) and REE patterns in both bulk and clay-size fraction.


Author(s):  
Michael Tite ◽  
Gareth Hatton

Egyptian blue was first used as a pigment on tomb paintings in Egypt from around 2300 BC, and during the subsequent 3,000 years, its use both as a pigment and in the production of small objects spread throughout the Near East and Eastern Mediterranean and to the limits of the Roman Empire. During the Roman period, Egyptian blue was distributed in the form of balls of pigment up to about 15mm across, and appears to have been the most common blue pigment to be used on wall paintings throughout the Empire. Egyptian blue was both the first synthetic pigment, and one of the first materials from antiquity to be examined by modern scientific methods. A small pot containing the pigment that was found during the excavations at Pompeii in 1814 was examined by Sir Humphrey Davy. Subsequently, x-ray diffraction analysis was used to identify the compound as the calcium-copper tetrasilicate C<sub>a</sub>C<sub>u</sub>Si<sub>4</sub>O<sub>10</sub>, and to establish that Egyptian blue and the rare natural mineral cuprorivaite are the same material. Examination of Egyptian blue samples in cross-section in a scanning electron microscope (SEM) revealed that they consist of an intimate mixture of Egyptian blue crystals (i.e. C<sub>a</sub>C<sub>u</sub>Si<sub>4</sub>O<sub>10</sub>) and partially reacted quartz particles together with varying amounts of glass phase (Tite, Bimson, and Cowell 1984). At this stage it should be emphasized that, in the literature, the term Egyptian blue tends to be used to describe both crystals of calcium-copper tetrasilicate and the bulk polycrystalline material that is used as the pigment and is sometimes referred to as frit. In this chapter, the suffix ‘crystal’ or ‘mineral’ will be added when the former meaning applies, and the suffix ‘pigment’, ‘sample’, or ‘frit’ will be added when the latter meaning applies. For the current study, a small group of Roman Egyptian blue samples were examined using scanning electron microscopy (SEM) with attached analytical facilities. Using the chemical compositions of the samples, together with the description of the manufacture of Egyptian blue given by Vitruvius (Morgan 1960) at the beginning of the first century BC in his Ten Books on Architecture, an attempt is made to identify the raw materials used in the production of Roman Egyptian blue.


2019 ◽  
Vol 11 (7) ◽  
pp. 1995 ◽  
Author(s):  
Sabrina Cajamarca ◽  
Douglas Martins ◽  
Juscimar da Silva ◽  
Mariana Fontenelle ◽  
Ítalo Guedes ◽  
...  

Several agro-industrial, livestock, and food wastes can be recycled to create biofertilizers. This diversity of raw materials can result in nutritional imbalance and an increase in heavy metal content, which could make the final product unfeasible. Thus, the chemical characterization of the raw materials and their influence on the sustainable and safe production of biofertilizers need to be better understood. In this context, the objective of the present study was to evaluate the chemical characteristics of agro-industrial residues used in the manufacture of an aerobic liquid biofertilizer. We analyzed the macronutrient, micronutrient, and trace metal contents of seven waste products used as raw materials to create a biofertilizer. In addition, a survey of secondary biofertilizer data from different residues was carried out that showed great heterogeneity in the chemical compositions of these residues, which has a direct impact on the agronomic efficiency of these biofertilizers. The characterization revealed that some materials may be contaminants of the soil, due to high levels of trace metals, especially cadmium. We conclude that the generation of detailed inventories, such as those of the nutrient and heavy metal contents of the raw materials and biofertilizers produced, is indispensable for the correct recommendation of biologically-based inputs in agriculture.


2011 ◽  
Vol 233-235 ◽  
pp. 210-213
Author(s):  
Li Qing Li ◽  
Hong Zhong ◽  
Liu Yin Xia

Employed methanol, toluene, formaldehyde, 4-tert-octylphenol, and hydroxylamine as raw materials, triumphantly obtained a new extractant for copper by the processes of salinization reaction, formylation reaction, oximate reaction and so on, the purity of new extractant is > 98% by purity test. The extraction performances are very perfect. The maximal extraction efficiency is up to 90.4% for Cu2+by single-stage extraction, and recovering Cu2+in 170g/L H2SO4medium by stripping, stripping of copper >99.3% can be obtained. The preparation cost of the extractant is very low. It can contribute to better development of hydrometallurgy for copper, and gradually reduce dependence of Chinese copper industries on overseas corporations.


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