scholarly journals The effect of nepheline syenite addition on pyroplastic deformation of sanitarywares

2018 ◽  
Vol 50 (1) ◽  
pp. 85-94
Author(s):  
Tuna Aydın ◽  
Nazım Kunduracı ◽  
Atamer Akbay

Nepheline syenite is used instead of feldspars as fluxing in ceramics. In this study, three ceramic bodies were prepared. Nepheline syenite was substituted by Na feldspar in the ratio of maximum 30 wt.%. The pyroplastic deformation was evaluated together with technological properties, including linear shrinkage, water absorption and strength. Phase and microstructural characteristics were also investigated. Results showed that the addition of nepheline syenite provided a decrease in viscosity. The decrease in viscosity caused an increase in the tendency for pyroplastic deformation in bodies containing nepheline syenite; however, this result shows that bodies containing nepheline syenite can be sintered at a lower temperature than the standard body. The addition of nepheline syenite also decreased water absorption and increased strength.

2015 ◽  
Vol 1088 ◽  
pp. 395-398
Author(s):  
Luiz Oliveira Veriano dalla Valentina ◽  
Marilena Valadares Folgueras ◽  
Wanessa Rejane Knop ◽  
Maria Cristina Pacheco do Nascimento ◽  
Glaucia Aparecida Prates

The work evaluates the possibility of the use the exhauster powder generated in the foundry process in ceramic mass atomized semigre type. The raw materials used were semi-stoneware kind atomized powder used on the coating ceramic manufacturing and dust exhaust byproduct supplied by a foundry industry both from brazilian industries . Tests were conducted using a heating rate of 10o.C / min and oxidant and / or inert atmosphere. Specimens contained different amounts of byproduct to the extent of 30% by mass, in order to verify the maximum addition of byproduct and were used in order to analyze the technological properties evaluation (water absorption linear shrinkage, bulk density). at the temperature of 1100 ° C showed higher difference between the results obtained and 1200o C this difference decreased.


2015 ◽  
Vol 820 ◽  
pp. 449-454
Author(s):  
Alline Sardinha Cordeiro Morais ◽  
Thais Mardegan Louzada ◽  
Veronica Scarpini Candido ◽  
Sergio Neves Monteiro ◽  
Carlos Mauricio Fontes Vieira

The incorporation of industrial wastes into clayey ceramics used in civil construction is becoming a worldwide procedure not only to provide an environmentally correct destination for the waste but, in some cases, to improve the ceramic properties. The objective of the present work was to evaluate the effect of incorporation of a glass powder waste from decontamination process of fluorescent lamps into clayey ceramics. This evaluation was performed based on the technological properties of water absorption, linear shrinkage ad flexural strength. The properties evaluation was complemented by optical microscopy structural observation. The glass waste was incorporated in up to 30 wt% and specimens were uniaxially pressed at 20 MPa and fired at a relatively higher temperature of 1000°C. The results confirmed a substantial improvement of both the water absorption and the strength with glass waste incorporation into clayey ceramics.


Cerâmica ◽  
2010 ◽  
Vol 56 (339) ◽  
pp. 285-290 ◽  
Author(s):  
P. Hettiarachchi ◽  
J. T. S. Motha ◽  
H. M. T. G. A. Pitawala

This study focuses on the identification of an appropriate composition of raw materials for ceramic products from commonly available red clays in Sri Lanka. The raw materials were characterized in terms of particle size distribution, chemical and mineralogical composition. Different formulations of samples were prepared, and the linear shrinkage, water absorption and flexural strength of the final products were measured. Microstructures of fired samples were observed under a scanning electron microscope. The best quality product was obtained when the sample contains a high amount of illite clay in a mixture of 80 wt.% clay-silt and 20 wt.% sand. The presence of higher concentrations of the metal oxides Na2O, K2O and Fe2O3 (total ~21 wt.%) in the clay-silt fraction of samples has resulted in obtaining higher technological properties of the body. The flexural strength and the water absorption of the product are 26.82 MPa and 6.51% respectively. If the raw materials contain lower amounts of the oxides Na2O, K2O and Fe2O3, higher amounts of clay-silt fraction (up to 90 wt.%) must be added to obtain an optimum quality product.


2014 ◽  
Vol 798-799 ◽  
pp. 526-531 ◽  
Author(s):  
Aline Marcia Ferreira Dias da Silva ◽  
Rosane Toledo ◽  
Veronica Scarpini Candido ◽  
Sergio Neves Monteiro ◽  
Carlos Maurício Fontes Vieira ◽  
...  

The microstructural and technological properties of clay ceramic incorporated with 10 and 20 wt% of elephant grass ashes were investigated at different firing temperatures of 650, 850 and 1050oC. X-ray diffraction were used to obtain the minerals and phase compositions. The microstructure was analyzed by scanning electron microscopy. The technical properties related to water absorption, linear shrinkage and flexural rupture strength were obtained by standard test. The results showed significant changes in the microstructure and phasic composition with increasing firing temperature. A marked improvement in the water absorption, decreasing to 18% as well as increase in strength, above 5 MPa, was found at 1050°C. However, only a slight contribution might be attributed to the incorporation of elephant grass ash. Nevertheless, its use as a by-product and the associated saving in clay are relevant environmental and economical advantages.


2018 ◽  
Vol 930 ◽  
pp. 164-169 ◽  
Author(s):  
Felipe de Luca Sartor ◽  
Luís Philipe Spricigo ◽  
Danila Ferreira Niero ◽  
Adriano Michael Bernardin ◽  
Oscar Rubem Klegues Montedo ◽  
...  

TheNossa Senhora do Carmomining company, located at the southern of Santa Catarina (SC), Brazil, explores a large amount of feldspar to the ceramic market. As a result, waste is inevitable in the production and processing of the feldspar mineral, which results in an environmental impact. Therefore, this study aims to evaluate the effect of the addition of the waste coming from the feldspar mining in the composition of ceramic bricks. In this way, the waste and a clay mineral were characterized. The waste (0, 5, 15 and 25 wt%) was added to a composition of clay brick based on a standard clay fromMorro da Fumaça, Santa Catarina, Brazil. Specimens were extruded and sintered at temperatures of 1123, 1223, and 1323 K. The technological properties assessed in this study were linear shrinkage, water absorption and bending strength. The data were assessed by analysis of variance. The results showed the feasibility of adding 15 and 25 wt% of waste to the brick composition. All technological properties were improved when compared to pure samples, except for linear shrinkage. The analysis of variance showed significant and reproducible effects for the water absorption results. The results for linear shrinkage and bending strength showed no statistical significance.


2014 ◽  
Vol 798-799 ◽  
pp. 509-513 ◽  
Author(s):  
Michelle Pereira Babisk ◽  
Thalissa Pizetta Altoé ◽  
Henrique Junio de Oliveira Lopes ◽  
Ulisses Soares do Prado ◽  
Monica Castoldi Borlini Gadioli ◽  
...  

The red mud is a well known insoluble residue generated in the Bayer process to benefit bauxite ores. This residue is composed of ceramic related compounds such as iron oxide, sodium aluminum silicates, carbonates, calcium aluminates and titanium dioxide. The incorporation of industrial residues in clay ceramics has been extensively investigated, not only as an environmentally correct solution but also as an economic way to save raw materials. Therefore, the present work evaluated the properties of clay ceramics incorporated with up to 40 wt% of red mud. Clay bodies with different percentages of red mud were press-molded and fired at 750, 950 and 1050°C. The evaluated technological properties were linear shrinkage, water absorption and mechanical strength. Sensible changes in such properties were found with red mud addition. In particular, the ceramic fired at 1050°C displayed favorable water absorption with red mud incorporation.


Author(s):  
G. Wie-Addo ◽  
A. H. Jones ◽  
S. Palmer ◽  
V. Starinieri ◽  
J. Renshaw ◽  
...  

AbstractThe influence of inorganic minerals (colemanite and nepheline syenite) as additives for sustainable clay brick manufacture has been examined. Each additive was added at 4 wt% to 96 wt% brick clay and samples were fired to 950 °C and 1040 °C and then compared with samples of 100% brick clay. Multiple analytical techniques (X-ray fluorescence, dilatometry, boiling water absorption, volumetric shrinkage, and mercury porosimetry) were used for analysis. Dilatometry shows that the additives influenced the temperature at which shrinkage began and the extent of that shrinkage. The use of colemanite reduced the temperature at which the shrinkage began by 120 °C and nepheline syenite reduced it by 20 °C. A linear shrinkage in dilatometry of 1% (from the maximum expanded length) was achieved at 1000 °C for 100% clay, 875 °C for colemanite additions and 970 °C for nepheline syenite additions. However, for samples fired at 1040 °C for 2 h colemanite containing samples had significantly lower volumetric shrinkage and higher water absorption than 100% clay and nepheline syenite samples, suggesting the presence of higher amounts of open porosity caused by the decomposition of the colemanite on heating. Samples containing nepheline syenite had a lower volumetric shrinkage but also a marginally lower water absorption than the 100% clay. The further optimisation of these or similar additives could potentially provide energy saving opportunities and reductions in CO2 emissions for brick manufacturers.


Cerâmica ◽  
2019 ◽  
Vol 65 (375) ◽  
pp. 426-431
Author(s):  
T. H. Silva ◽  
A. C. M. Castro ◽  
F. C. Valente Neto ◽  
M. M. N. S. Soares ◽  
D. S. de Resende ◽  
...  

Abstract This study characterized discarded sanitary ware waste (SWW) that could not meet quality requirements. To understand the composition of such SWW, samples were collected, processed, and characterized. This SWW was used to substitute granite in ceramic slips, and the final recycled sanitary ware compositions of 5%, 10%, 25%, 50% and 100% were obtained. Then, the mixtures were evaluated based on density, rheology, linear shrinkage, water absorption, and flexural strength. The results for viscosity and pyroplastic deformation in specimens containing the ceramic waste were better than the reference slip used in a production line. Results for density, water absorption and linear shrinkage showed no significant difference from the control samples. Although the replacement of more than 5% of granite reduced the flexural strength, no tested specimen was below the minimum value required by the industry.


2006 ◽  
Vol 530-531 ◽  
pp. 544-549 ◽  
Author(s):  
P.M. Andrade ◽  
Carlos Maurício Fontes Vieira ◽  
Sérgio Neves Monteiro ◽  
F. Vernilli Jr.

The present paper has for objective to evaluate the effect of fine steel sludge waste incorporation on the properties and microstructure of a kaolinitic clayey body used to the fabrication of bricks and roofing tiles. Compositions were prepared with additions of waste of 0, 5 and 10 wt.% in a kaolinitic clay from the county of Campos dos Goytacazes, State of Rio de Janeiro, Brazil. To determine the technological properties such as bulk density, linear shrinkage, water absorption and flexural strength, specimens were prepared by uniaxial pressure at 20 MPa and then fired in a laboratory furnace at 700°C, 900°C and 1100°C. The microstructure of the fired specimen was evaluated by SEM. The results showed that the incorporation up to 10 wt. % of fine steel sludge does not change the ceramic properties, specially, at low temperatures. Hence, the recycling of steel sludge into red ceramic fabrication can be considered as an environmentally correct solution for the final disposal of this type of waste.


Cerâmica ◽  
2012 ◽  
Vol 58 (347) ◽  
pp. 393-399 ◽  
Author(s):  
G. T. Saleiro ◽  
J. N. F. Holanda

This work reports on the processing of red ceramic for civil construction using fast-firing cycles. The firing cycle is an important variable in the processing of red ceramic materials, which contributes to a high consumption of energy. The red ceramic pieces were prepared by industrial extrusion and fired at firing temperatures varying from 700 ºC to 1100 ºC using different firing cycles (slow-firing cycle - 1º C/min and fast-firing cycle - 10 ºC/min and 20 °C/min). The technological properties (linear shrinkage, water absorption, apparent porosity, apparent density, and flexural strength) as function of the firing temperature and firing cycle are investigated. The development of the microstructure was followed by SEM/SEI. The results showed that fast-firing red ceramics exhibits technological properties and microstructure comparable to conventionally fired red ceramics, resulting in great advantages in energy saving.


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