Technological Methods of Obtaining Heat-Efficient Ceramic Materials from Unconditioned Clayey Raw Material

The object of research is low-melting clays of the Kyiv region (Ukraine). The work is devoted to the study of obtaining ceramic materials resistant to low temperatures. Frost resistance is one of the most important characteristics for regions in which ceramic materials are used with frequent temperature transitions through 0 °C. The production of frost-resistant ceramic wall materials is determined by the type of raw materials and technological production parameters. The main technological methods for increasing frost resistance are: the use of less dispersed clays; batch homogenization; formation of raw material without textural defects and prevention of cracks during drying and firing. The work shows that the existing methods for increasing frost resistance can be implemented by reducing water absorption due to the creation of a microporous structure with predominantly closed pores by increased pressure of a semi-dry method of formation. An increase in the pressing pressure leads to an increase in the number of contacts of the molecules of the ceramic mass at the stage of formation. Due to this, the strength of the molded samples at a pressing pressure of more than 30 MPa is higher compared to samples molded by the plastic method. It was also found that an increase in the pressing pressure makes it possible to speed up the drying process of ceramic products, reducing energy consumption for their production. Due to an increase in the pressing pressure to 50 MPa, the strength of samples obtained by semi-dry pressing is 55.4 MPa, while for samples during plastic formation it is 22.9 MPa. Water absorption, on the contrary, for dry pressing is 9.3 %, while for plastic pressing it is 12.2 % at a firing temperature of 1000 °C. It is shown that increasing the pressing pressure is an effective way to improve the quality of ceramic materials based on local low-plasticity clay raw materials. Saving natural and energy resources, developing new sources of raw materials and comprehensive improvement of products with environmental friendliness of production remain important today.

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Treatment of Soil Contaminated by Mining Activities to Prevent Contamination by Encapsulation in Ceramic Construction Materials

Materials ◽

10.3390/ma14226740 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6740

Author(s):

Juan María Terrones-Saeta ◽

Jorge Suárez-Macías ◽

Antonio Bernardo-Sánchez ◽

Laura Álvarez de Prado ◽

Marta Menéndez Fernández ◽

...

Keyword(s):

Ceramic Material ◽

Contaminated Soil ◽

Toxic Elements ◽

Construction Materials ◽

Well Being ◽

Ceramic Materials ◽

Potentially Toxic Elements ◽

Raw Material ◽

Mining District ◽

Different Soils

Mining is an essential activity for obtaining materials necessary for the well-being and development of society. However, this activity produces important environmental impacts that must be controlled. More specifically, there are different soils near new or abandoned mining productions that have been contaminated with potentially toxic elements, and currently represent an important environmental problem. In this research, a contaminated soil from the mining district of Linares was studied for its use as a raw material for the conforming of ceramic materials, bricks, dedicated to construction. Firstly, the contaminated soil was chemically and physically characterized in order to evaluate its suitability. Subsequently, different families of samples were conformed with different percentages of clay and contaminated soil. Finally, the conformed ceramics were physically and mechanically characterized to examine the variation produced in the ceramic material by the incorporation of the contaminated soil. In addition, in this research, leachate tests were performed according to the TCLP method determining whether encapsulation of potentially toxic elements in the soil occurs. The results showed that all families of ceramic materials have acceptable physical properties, with a soil percentage of less than 80% being acceptable to obtain adequate mechanical properties and a maximum of 70% of contaminated soil to obtain acceptable leachate according to EPA regulations. Therefore, the maximum percentage of contaminated soil that can be incorporated into the ceramic material is 70% in order to comply with all standards. Consequently, this research not only avoids the contamination that contaminated soil can produce, but also valorizes this element as a raw material for new materials, avoiding the extraction of clay and reducing the environmental impact.

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SYNTHESIS AND CHARACTERIZATION OF GREENER CERAMIC MATERIALS WITH LOWER THERMAL CONDUCTIVITY USING OLIVE MILL SOLID BYPRODUCT

EUREKA Physics and Engineering ◽

10.21303/2461-4262.2020.001116 ◽

2020 ◽

Vol 1 ◽

pp. 96-106 ◽

Cited By ~ 1

Author(s):

Xenofon Spiliotis ◽

Vayos Karayannis ◽

Stylianos Lamprakopoulos ◽

Konstantinos Ntampegliotis ◽

George Papapolymerou

Keyword(s):

Thermal Conductivity ◽

Solid Waste ◽

Energy Savings ◽

Sintering Temperature ◽

Ceramic Body ◽

Ceramic Materials ◽

Raw Material ◽

Gravimetric Analysis ◽

Olive Mill Solid Waste ◽

Olive Mill

In the current research, the valorization of olive mill solid waste as beneficial admixture into clay bodies for developing greener ceramic materials with lower thermal conductivity, thus with increased thermal insulation capacity towards energy savings, is investigated. Various clay/waste mixtures were prepared. The raw material mixtures were characterized and subjected to thermal gravimetric analysis, in order to optimize the mineral composition and maintain calcium and magnesium oxides content to a minimum. Test specimens were formed employing extrusion and then sintering procedure at different peak temperatures. Apparent density, water absorption capability, mechanical strength, porosity and thermal conductivity were determined on sintered specimens and examined in relation to the waste percentage and sintering temperature. The experimental results showed that ceramic production from clay/olive-mill solid waste mixtures is feasible. In fact, the mechanical properties are not significantly impacted with the incorporation of the waste in the ceramic body. However, the thermal conductivity decreases significantly, which can be of particular interest for thermal insulating materials development. Furthermore, the shape of the produced ceramics does not appear to change with the sintering temperature increase.

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INFLUENCE OF VARIOUS SPECIES OF TECHNOLOGICAL PROCESSING OF TREPANG ON THE CONTENT OF TRITERPENE GLYCOSIDES AND SELENIUM IN WASTE OF ITS PROCESSING

Известия вузов. Пищевая технология ◽

10.26297/0579-3009.2018.5-6.14 ◽

2018 ◽

Author(s):

А.И. ЧЕПКАСОВА ◽

Н.Б. АЮШИН ◽

Т.Н. СЛУЦКАЯ ◽

Л.Т. КОВЕКОВДОВА

Keyword(s):

Apostichopus Japonicus ◽

Food Additives ◽

Dry Weight ◽

Biologically Active ◽

Raw Material ◽

Active Components ◽

Technological Processing ◽

Cooking Water ◽

Far Eastern ◽

Technological Methods

Исследована возможность использования непищевых отходов разделки трепанга дальневосточного в качестве сырья для производства БАД на основе селена и гликозидов. В качестве объектов исследования использовали отходы переработки Apostichopus japonicus: прианальные участки и венчики с щупальцами и варочные воды. Исследовано содержание селена и гликозидов в трепанге и отходах его разделки, а также содержание и распределение селена и гликозидов при гидротермической и ферментативной обработке трепанга и отходов его разделки. Установлено, что содержание селена в трепанге и отходах составляет 9,0 и 11,5 мкг/г соответственно. Увеличение кратности варки до трех приводит к накоплению селена в варочной воде из трепанга до 30,5 мкг/г, а из отходов – до 107,5 мкг/г. Показано, что при варке трепанга гликозиды высвобождаются активнее. Содержание гликозидов в трехкратной варочной воде из трепанга составляет 162, а из отходов трепанга – 112 мг на 1 г сухого веса. Обоснована суточная дозировка БАД, разработанных по предлагаемым технологическим приемам. Показана возможность использования непищевых отходов, полученных при переработке трепанга, в качестве сырья для производства БАД как источника минорных биологически активных компонентов – селена и гликозидов. The purpose of the study: assessment of the possibility of using non-food waste from cutting trepang as a raw material for the production of biologically active food additives based on the determination of the content and ratio of selenium and glycosides. As objects of the study, the Far Eastern trepang (Apostichopus japonicus), waste from its processing: prianal areas and corollas with tentacles and cooking water were used. The content of selenium and glycosides in trepang and waste from its cutting, as well as the content and distribution of selenium and glycosides during hydrothermal and enzymatic treatment of trepang and waste from its cutting, are studied. It was found that the content of selenium in trepang and wastes is 9,0 and 11,5 мg/g, respectively. An increase in the cooking rate to three leads to the accumulation of selenium in cooking water from trepang to 30,5 мg/g, and from waste to 107,5 мg/g. It is shown that glycosides are more actively released when trepang cooking, in comparison with waste. The content of glycosides in triple cooking water from trepang is 162 mg, and from the waste – 112 mg per one gram of dry weight. The daily dosage for dietary supplements developed based on the proposed technological methods is substantiated. The possibility of using non-food wastes obtained during trepang processing as a raw material for the production of biologically active food additives as a source of minor biologically active components – selenium and glycosides is shown.

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Ceramic Composition Material with Mullite Crystals Obtained from the Clayy Raw Material of Yakutia

Materials Science Forum ◽

10.4028/www.scientific.net/msf.992.253 ◽

2020 ◽

Vol 992 ◽

pp. 253-258

Author(s):

M.P. Lebedev ◽

V.N. Tagrov ◽

E.S. Lukin

Keyword(s):

Building Materials ◽

Raw Materials ◽

Practical Interest ◽

Physical And Mechanical Properties ◽

Ceramic Materials ◽

Strength Properties ◽

Raw Material ◽

Composition Material ◽

Material Base ◽

Wide Range

The article deals with the manufacture of modern structural ceramic materials from clay and loam deposits of the Republic of Sakha (Yakutia). The importance and relevance of the development of the production of building materials from local raw materials is emphasized, since this will certainly affect the effectiveness of the construction complex as a whole. The successful development of the construction complex is capable of not only stimulating growth in all sectors of the economy, but also contributes to solving the most pressing social problems. Today, Yakutia has huge reserves of mineral raw materials for the production of a wide range of building materials and products. Of practical interest are wall materials made from clay soils. Given the features of the region’s raw material base, this work focuses on additional processing of traditional material. Controlling the complex physicochemical and structural-mechanical transformations that occur during heat treatment, a methodology has been developed for creating a composite material that will allow competitive innovative materials with enhanced strength properties to be produced with a reinforcing element with a glassy phase matrix of mullite crystals. The fabricated samples have a wide range of physical and mechanical properties and allow using it as a high-quality structural building ceramics, as well as industrial floor technical tile.

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Effect of Si3N4-Y2O3 Compound Additive on Crystallization and Sintering of Fused Quartz Ceramic Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.713 ◽

2011 ◽

Vol 335-336 ◽

pp. 713-716

Author(s):

Shu Long Liu ◽

Zhi Fa Wang ◽

Jing Long Bu ◽

Shu Bin Shen ◽

Li Xue Yu

Keyword(s):

Thermal Expansion ◽

Bending Strength ◽

Ceramic Materials ◽

Quartz Ceramic ◽

Apparent Porosity ◽

Raw Material ◽

Expansion Rate ◽

Obvious Effect ◽

Fused Quartz

Fused quartz granules (d50=19 μm) were used as raw material, and Si3N4-Y2O3 (1:1, in mass) was used as additive with dosages of 1%, 2% and 3% (in mass). Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. The effect of Si3N4-Y2O3 on crystallization and sintering of the fused quartz ceramic materials were researched by measurements of apparent porosity, bending strength and thermal expansion rate (RT~1200 °C), and by the analyses of XRD and SEM. The results showed that the samples sintered at each temperature with 3% Si3N4-Y2O3 had the lowest apparent porosity, the highest bending strength and more compact microstructure. This indicated that 3% Si3N4-Y2O3 was conducive to sintering of fused quartz ceramic materials. The results of XRD and thermal expansion rate showed that addition of 3% Si3N4-Y2O3 compound had obvious effect on inhibiting crystallization of the samples sintered at various temperatures. It can be deduced that the Si3N4-Y2O3 compound plays the best role in inhibiting crystallization and facilitating sintering of fused quartz ceramic materials.

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Industrial Ceramic Blocks for Buildings: Clay Characterization and Drying Experimental Study

Energies ◽

10.3390/en13112834 ◽

2020 ◽

Vol 13 (11) ◽

pp. 2834

Author(s):

A.M. Vasconcelos da Silva ◽

J.M.P.Q. Delgado ◽

A.S. Guimarães ◽

W.M.P. Barbosa de Lima ◽

R. Soares Gomez ◽

...

Keyword(s):

Mass Loss ◽

Particle Diameter ◽

Ceramic Materials ◽

Raw Material ◽

Average Particle ◽

Ceramic Block ◽

Ceramic Blocks ◽

Dimensional Variation ◽

Forced Air ◽

Air Circulation

The conformation of a ceramic piece follows the steps of preparing the raw material, molding, lamination, drying, and firing. Drying is a thermodynamic process of heat and mass transfer, with dimensional variations of the product that requires a large amount of energy. Ceramic materials when exposed to non-uniform drying may suffer cracks and deformations, reducing their post-drying quality. Thus, this work aimed to study the drying of industrial ceramic blocks in an oven with forced air circulation. Experiments were carried out to characterize the clay and drying of the ceramic block at temperatures ranging from 50 °C to 100 °C. Results of the chemical, mineralogical, granulometric, differential thermal, and thermogravimetric analysis of the clay, and heating kinetics, mass loss, and dimensional variation of the industrial ceramic block are presented and analyzed in detail. It was found that the clay is basically composed of silica and alumina (≈ 80.96%), with an average particle diameter of 13.36 μm. The study proved that drying at high temperature and low relative humidity of the air generates high rates of mass loss, heating, and volumetric shrinkage in the ceramic product, and high thermo-hydraulic stresses, which cause the appearance and propagation of cracks, gaps, and cleavages, compromising the final quality of the product.

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Preparation of Self-Releasing Glaze Ceramic Materials Utilizing Red Mud

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.383-390.3366 ◽

2011 ◽

Vol 383-390 ◽

pp. 3366-3373

Author(s):

Shuo Qin ◽

Bo Lin Wu ◽

Shiao Zhao ◽

Cong Chang Ma ◽

Zu Sheng Hu

Keyword(s):

Mechanical Properties ◽

Red Mud ◽

Barium Carbonate ◽

Raw Materials ◽

Normal Pressure ◽

Ceramic Materials ◽

The Self ◽

Raw Material ◽

Radiation Level ◽

Red Sandstone

Red mud is the main solid residue generated during the production of alumina by means of the Bayer process. In order to expand the comprehensive utilization field of red mud and develop new ceramic products with low radioactivity utilizing red mud, the exploration of preparing self-releasing glaze ceramic materials using red mud as raw material was carried out. During the exploration, the self-releasing glaze ceramic materials with low radiation level were produced by normal pressure sintering process using the main ingredients of red mud, red sandstone, barium carbonate and ball clay. The properties of the self-releasing glaze ceramic samples were investigated by the measurements of mechanical properties, X-ray diffraction (XRD), scanning electron microscopy (SEM) and radiation measurement. The results show that the self-releasing glaze ceramic materials have good mechanical properties (the bulk density, 3.10 g/cm3; the compressive strength, 78.00 MPa). Adding barium carbonate to the raw materials and then calcine them to ceramics, which can extend the sintering temperature range and the radioactivity level of the self-releasing glaze ceramic materials can be reduced to that of the natural radioactive background of Guilin Area, Karst landform (the average 60 Total/Timer).

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The Use of Carbonate Sludge in the Production of Porous Aggregate

Ecology and Industry of Russia ◽

10.18412/1816-0395-2020-6-15-19 ◽

2020 ◽

Vol 24 (6) ◽

pp. 15-19

Author(s):

A.V. Kolpakov ◽

E.S. Abdrakhimova

Keyword(s):

Industrial Waste ◽

Liquid Glass ◽

Glass Composition ◽

Physical And Mechanical Properties ◽

Ceramic Materials ◽

Environmental Safety ◽

Raw Material ◽

Material Base ◽

Carbonate Sludge ◽

The Russian Federation

The possibilities of obtaining porous fillers based on carbonate sludge and liquid-glass composition are considered. One of the issues of industrial waste disposal is the creation of waste-free technologies. The use of nanotechnology-based carbonate sludge in the production of porous aggregates increases environmental safety. A porous aggregate with high physical and mechanical properties was obtained. The use of carbonate sludge in the production of porous aggregate contributes to: a) recycling of industrial waste; b) environmental protection; C) expanding the raw material base for obtaining ceramic materials for construction. A patent of the Russian Federation was obtained for the obtained method of producing a porous aggregate using a liquid-glass composition.

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Influence of Nano-Y2O3 on Crystallization Behavior and Sintering Performance of Fused Quartz Ceramic Materials

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.284-286.1366 ◽

2011 ◽

Vol 284-286 ◽

pp. 1366-1369

Author(s):

Yue Jun Chen ◽

Zhi Fa Wang ◽

Li Xue Yu ◽

Jing Long Bu ◽

Rong Lin Wang ◽

...

Keyword(s):

Thermal Expansion ◽

Bending Strength ◽

Ceramic Materials ◽

Quartz Ceramic ◽

Apparent Porosity ◽

Raw Material ◽

Expansion Rate ◽

Peak Intensity ◽

Fused Quartz ◽

Crystallization Inhibitor

Fused quartz granule (d50=0.019 mm) was used as raw material, nano-Y2O3 (size<0.08 μm) was used as additive with dosages of 1% (in mass, similarly hereinafter), 2% and 3%. Fused quartz ceramic materials were fabricated in reduction atmosphere at 1300 °C, 1350 °C and 1400 °C for 1 h. Properties of samples were researched by measurements of apparent porosity, bending strength and thermal expansion rate, and analyzed by XRD and SEM. The results showed that additive nano-Y2O3 had good inhibiting effect on crystallization of fused quartz sintered at various temperatures, sample added 2% nano-Y2O3 had least thermal expansion rate, diffraction peak intensity and apparent porosity, and it had higher bending strength and more compact microstructure, especially sample sintered at 1350 °C. It can be deduced that 2% nano-Y2O3 plays the excellent role as the crystallization inhibitor and sintering assistant to fused quartz materials sintered at various temperatures.

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