scholarly journals Study of the High-temperature Synthesis of MgAl2O4 Spinel Refractory Raw Materials from Chromium Slag

2018 ◽  
Vol 37 (6) ◽  
pp. 581-586 ◽  
Author(s):  
Jinxia Meng ◽  
Weiqing Chen ◽  
Jizeng Zhao ◽  
Li Liu
Keyword(s):  
Raw Materials ◽  
Melting Process ◽  
Volume Density ◽  
Raw Material ◽  
Electric Melting ◽  
Sintering Process ◽  
Spinel Refractory ◽  
Chromium Slag ◽  
High Temperature Synthesis ◽  
Shock Resistance

AbstractTo make use of chromium slag waste, this study examined the technology of the preparation of MgAl2O4 spinel refractory raw material by using chromium slag. The results showed that (1) using the traditional sintering process of synthetic spinel, the highest volume density was 3.14 g/cm3 and the lowest porosity rate was 9.16 %. With the increase of the proportion of MgO powder mixing, bulk density and porosity fluctuations, and which cannot meet the requirements of refractory raw materials. (2) For MgAl2O4 spinel prepared by the electric-melting process, the highest volume density was 3.27 g/cm3 and the lowest porosity rate was 8.78 %. Volume density and the porosity remained stable, and they are affected by MgO powder thus the blending ratio is very small, which can satisfy the requirements of refractory raw materials. (3) MgAl2O4 spinel prepared by the electric-melting method is superior to traditional MgAl2O4 spinel in terms of slag resistance and thermal shock resistance.

scholarly journals High strength glass-ceramics sintered with coal gangue аs а raw material

2019 ◽  
Vol 51 (3) ◽  
pp. 285-294
Author(s):  
Dang Wei ◽  
H.-Y. He
Keyword(s):  
Building Materials ◽  
Raw Materials ◽  
Glass Ceramics ◽  
High Strength ◽  
Coal Gangue ◽  
Raw Material ◽  
Sintering Process ◽  
Forming Process ◽  
Sintered Glass ◽  
Utilization Ratio

High strength lightweight glass-ceramics were fabricated with coal gangue and clay as main raw materials. The utilization ratio of coal gangue, the ratio of the coal gangue with clay, mineralization agents, forming process and sintering process on the properties of the fabricated glass-ceramics were optimized. The utilization ratio of coal gangue reached 75, and the ratio of coal gangue to clay was 3/1, as an optimal property was observed. The optimal sintering temperature was found to be 1370?C. At this optimal temperature, the sintered glass-ceramics showed the main phase of mullite and spindle and so showed high strength, low density, and low water absorbance. The appropriate amounts of codoping of the TiO2, ZnO, and MnO2/dolomite as mineralization agents obviously enhanced the properties of the glass-ceramics. Process optimizations further determined reasonable and optimal process parameters. The high strength lightweight glass-ceramics fabricated in this work may be very suitable for various applications including building materials, cooking ceramics, and proppant materials, et al.

scholarly journals Karakterisasi Serbuk Timah dari Sistem Atomisasi Gas Argon Panas - Sub Sistem Gas Alir Tabung Gas

2021 ◽  
Vol 12 (1) ◽  
pp. 181
Author(s):  
Abdul Basyir ◽  
Didik Aryanto ◽  
Jayadi Jayadi ◽  
Wahyu Bambang Widayatno ◽  
Agus Sukarto Wismogroho
Keyword(s):  
Size Range ◽  
Raw Materials ◽  
Spherical Shape ◽  
Raw Material ◽  
Sintering Process ◽  
Spherical Powder ◽  
Melting Chamber ◽  
Chamber Temperature ◽  
Size Powder ◽  
Main Material

<p class="Abstract">The tin powder was used in some applications and technology such as for part manufacture through alloying, pressing, and sintering process, mixing material for the pyrotechnic application, the main material for solder pasta, mixing material on tin chemical, and others. Therefore, the demand for tin powder with a small size, spherical shape, and high purity is increasing severely. Indonesia (PT. Timah Tbk.) is one of the world’s largest producers of tin raw materials. This raw material can be processed be as powder by the atomization method. In this research, hot argon gas atomization system was used to generated tin powder. Raw tin was melted in a melting chamber with temperature variations of 600, 700, 800, and 900 °C. This experiment generates powder with a dominant size of 37 – 150 mm. Meanwhile, for size powder of 0 – 30 mm, dominated by size range of 0 – 10 mm. Furthermore, the size powder of 0 – 30 mm is composed of tin phase, without tin oxide. The tin powder of melting chamber temperature of 900 °C produces the largest tin powder with a size of 0 – 10 mm and spherical powder.</p>

scholarly journals Influence of the increased content of Calumite blast-furnace slag on the melting of sodium–calcium–silicate glass

2019 ◽  
Vol 138 (6) ◽  
pp. 4571-4583
Author(s):  
Anna A. Kuśnierz ◽  
Magdalena Szumera ◽  
Magda Kosmal ◽  
Paweł Pichniarczyk
Keyword(s):  
Thermal Analysis ◽  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Raw Materials ◽  
Melting Process ◽  
Raw Material ◽  
Glass Mass ◽  
Sodium Calcium ◽  
The Cost ◽  
Furnace Slag

Abstract A glass set with a high content of blast-furnace slag and a reduced amount of traditional raw materials requires optimization of the raw material composition and adjustment of its specificity to the temperature regime of melting, homogenizing and clarifying the glass mass. The introduction of an increased amount of blast-furnace slag allows to reduce the cost of raw materials: soda, limestone and high-class sand, reduce energy costs, whose consumption significantly decreases and reduces CO2 emissions in line with EU requirements. The tests of thermal analysis of a glass set with different contents of Calumite are aimed at learning the mechanism of its operation by determining the changes caused by its different presence in the course of subsequent reactions between the components of the glass set. Analysis of the influence of the addition of different Calumite slag contents treated as a substitute for the raw material on the melting process of glassware sets was analyzed. The tests were carried out using differential thermal analysis (DTA) and thermogravimetry (TG) based on the model glass [mass%]: 73.0% SiO2, 1.0% Al2O3, 10.0% CaO, 2.0% MgO and 14.0% Na2O. The effect of combining Calumite with sulphate and multi-component fining agent—mixtures of As2O3, Sb2O3, NaNO3 in proportions of 1:1:1 for chemical reaction and phase transformation, was investigated.

Self-Propagating High-Temperature Synthesis for Immobilization of Simulated Radioactive Sandy Soil Waste

2012 ◽  
Vol 518-523 ◽  
pp. 2797-2801 ◽  
Author(s):  
Zhi Gui Qin ◽  
Xian He Mao ◽  
Min Chen ◽  
Xiao Ning Yuan ◽  
Kang Zhao ◽  
...  
Keyword(s):  
High Temperature ◽  
Sandy Soil ◽  
Crystalline Phase ◽  
Volume Density ◽  
Raw Material ◽  
Leaching Rate ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
High Temperature Synthesis ◽  
Solid Form

The immobilization of simulated radioactive sandy soil waste by using self-propagating high-temperature synthesis (SHS) was investigated. The products were characterized by density, X-ray diffraction, and scanning electron microscope. The leaching rate of tracer element was measured by the method of PCT (product consistency test). The SHS immobilization typically results in products containing amorphous phase and crystalline phase. The volume density of the final product is over 3.0g/cm3. The tracer element Ce in the final product mainly forms crystalline phase of CeAl11O18 and Ce2SiO5 when the amount of CeO2 in the raw material is large than 1%. The leaching rate of Ce for 28 days is about 10-5 g•m-2•d-1，which is much lower than that of the borosilicate glass solid form. the leaching rates of Ca, Si, Al and Fe during 28 days are about 10-3～10-4 g•m-2•d-1

Preparation and Properties of MgO-MgAl2O4-FeAl2O4 Bricks in Cement Kiln

2011 ◽  
Vol 250-253 ◽  
pp. 554-560 ◽  
Author(s):  
Shu Long Ma ◽  
Yong Li ◽  
Jia Lin Sun ◽  
Yue Li ◽  
Wen Bin Xia
Keyword(s):  
Compressive Strength ◽  
Thermal Shock ◽  
Adhesion Strength ◽  
Thermal Shock Resistance ◽  
Raw Materials ◽  
Volume Density ◽  
Cement Kiln ◽  
Particle Sizes ◽  
Tunnel Furnace ◽  
Shock Resistance

Sintered magnesia with different particle sizes, fused MgAl2O4and FeAl2O4were used as the raw materials. FeAl2O4is added in MgO-MgAl2O4bricks at different ratios to gradually replace MgAl2O4. After the raw materials were molded and sintered at the tunnel furnace with the temperature 1 530°C for 10 hours, the MgO-MgAl2O4-FeAl2O4bricks could be made. After the analysis of the phase composition, microstructure and routine performance of the specimens, the influence by adding FeAl2O4to the samples on the properties such as thermal shock resistance, adhesion strength of kiln crust are discussed as the key point. The result shows that the addition of FeAl2O4has no evidently influence on the apparent porosity and volume density. The cold compressive strength of the samples reduces gradually with the addition of FeAl2O4, and it decreases obviously when the amount of FeAl2O4is more than 8%. When the addition of FeAl2O4is 5% FeAl2O4in the MgO-MgAl2O4-FeAl2O4bricks, MgAl2O4and FeAl2O4can combine each other’s advantages. The thermal shock resistance not only decreased obviously but the adhesion strength to kiln crust is increased.

scholarly journals Preparation of Sintered Brick with Aluminum Dross and Optimization of Process Parameters

Coatings ◽  
2021 ◽  
Vol 11 (9) ◽  
pp. 1039
Author(s):  
Yu Zhang ◽  
Hongjun Ni ◽  
Shuaishuai Lv ◽  
Xingxing Wang ◽  
Songyuan Li ◽  
...  
Keyword(s):  
Process Parameters ◽  
Raw Materials ◽  
Raw Material ◽  
Molding Pressure ◽  
Optimum Process ◽  
Sintering Process ◽  
Aluminum Dross ◽  
Optimization Of Process Parameters ◽  
Protection Method ◽  
Engineering Soil

Aluminum dross is produced in the process of industrial production and regeneration of aluminum. Currently, the main way to deal with aluminum dross is stacking and landfilling, which aggravates environmental pollution and resource waste. In order to find a green and environmental protection method for the comprehensive utilization, the aluminum dross was used as raw materials to prepare sintered brick. Firstly, the raw material ratio, molding pressure and sintering process were determined by single factor test and orthogonal test, and the mechanism of obvious change of mechanical strength of sintered brick was studied by XRD and SEM. The experimental results show that, the optimal formula of sintered brick is 50% aluminum dross, 37.50% engineering soil and 12.50% coal gangue. The optimum process parameters are molding pressure 10 MPa, heating rate 8 °C/ min, sintering temperature 800 °C, holding time 60 min. The samples prepared under the above formula and process parameters present outstanding performance, and the compressive strength, flexural strength and water absorption rate are 16.21 MPa, 3.42 MPa and 17.12% respectively.

Alternative Soda-Lime Glass Batch to Reduce Energy Consumption

2013 ◽  
Vol 545 ◽  
pp. 24-30 ◽  
Author(s):  
Ekarat Meechoowas ◽  
Kanit Tapasa ◽  
Tepiwan Jitwatcharakomol
Keyword(s):  
Melting Temperature ◽  
Raw Materials ◽  
Glass Batch ◽  
Heat Content ◽  
Melting Process ◽  
Soda Lime ◽  
Raw Material ◽  
Soda Lime Glass ◽  
Kinetic Properties ◽  
Atmosphere Temperature

Soda-lime glass is produced by melting sand (SiO2), soda ash (Na2CO3), lime stone (CaCO3) together with effective additives such as dolomite (CaMg(CO3)2) and an important structural modification, alumina (Al2O3) in which the melting temperature is very high around 1500°C. With this reason, to dissolve alumina, high amount of energy is needed. Consequently, one of possibilities to reduce the melting energy is replacing alumina by the raw material with a lower enthalpy of melting. The heat required for melting the batch of raw materials from atmosphere temperature to melting temperature is called exploited heat (Hex), which can be calculated from chemical enthalpy (H°chem) and heat content (Hmelt) at reference temperature (Tex). From thermodynamic approach, chemical enthalpy of alumina is higher than feldspar (KAlSiO3) or pyrophyllite (Al2Si4O10(OH)2). For the glass batch with alumina, the calculated exploited heat is 540 kWh/ton while the batch with feldspar or pyrophyllite is lower, namely 534 and 484 kWh/ton, respectively. This means that the melting process can be emerged easier than the batch with alumina because the melting point of feldspar is around 1200°C and pyrophyllite dehydroxylates around 900°C. The kinetic properties of batch melting were investigated by Batch-Free Time method, which defines the melting ability of the modified batch. According to thermodynamic calculation, it was found that both alternative batches were melted easier. The study showed that feldspar or pyrophyllite could be used instead of alumina without significant changes in glass chemical composition and physical properties. The concern of using feldspar or pyrophyllite is the quantity of minor impurities which affect to the color appearance especially in clear glass products.

Potential Application of Palm Ash as a Raw Materials in Production of Green Glass

2012 ◽  
Vol 626 ◽  
pp. 1006-1009
Author(s):  
Hidayu Jamil Noorina ◽  
Mohd Mustafa Al Bakri Abdullah ◽  
Che Pa Faizul ◽  
Mohd Zaki Ruhiyuddin ◽  
Darus Murizam ◽  
...  
Keyword(s):  
Oil Palm ◽  
Raw Materials ◽  
Glass Production ◽  
Melting Process ◽  
Product Evaluation ◽  
Raw Material ◽  
Glass Product ◽  
Produce Glass ◽  
Green Glass ◽  
Oil Palm Ash

Oil Palm Ash is one of the abundance agricultural wastes found in Malaysia. This wastes need to be disposed properly. Oil palm ash contains compounds needed to produce glass. Most of raw materials (especially silica) used to produce existing commercial glass are imported; therefore it is the best time to highlight the potential of local natural waste as the raw material in glass production. In this study, raw material characterization, glass production and glass product evaluation has been done. A few parameters have been recognized to have effect on green glass production such as mixing compositions and firing temperature. Oil palm ash has been washed and dried then sieved to get uniformity of particle size. Then, oil palm ash is mixed with other glass materials such as alumina and flux and undergone melting process at 1400°C. Through the experiments, the best glass compositions are as follows: 80% palm ash, 10% kaolin and 10% feldspar or 10% dolomite while the suitable temperature being used for sintering process to produced end product is range between 1150°C to 1200°.

Chemical and Mineralogical Composition Influence of Steelworks Dust on Agglomerate Quality

2017 ◽  
Vol 1143 ◽  
pp. 120-126
Author(s):  
Vasilica Viorica Corcoţoi Toniţă ◽  
Maria Vlad ◽  
Ilenuta Severin ◽  
Andrei Berbecaru
Keyword(s):  
Experimental Research ◽  
Raw Materials ◽  
Mineralogical Composition ◽  
Raw Material ◽  
Sintering Process ◽  
Mineralogical Analysis ◽  
Secondary Raw Material ◽  
Chemical And Mineralogical Composition

From making steel process result dust and slurry that can be used as a secondary raw material in the composition stack of ferrous materials for the sintering process. Together with other raw materials rich in Fe, SiO2, CaO, this waste can be significant on quality ferrous agglomerate due to the useful elements contained.The paper presents the results of chemical and mineralogical analysis of steelworks dust and experimental research with a view to introduce dust in the sintering process to increase the quality of agglomerate.

scholarly journals Study on Manufacture of Production Line and Characteristics of Rice Straw Seedling Trays

CONVERTER ◽  
2021 ◽  
pp. 370-383
Author(s):  
Yifei Li, Et al.
Keyword(s):  
Moisture Content ◽  
Rice Straw ◽  
Production Line ◽  
Shear Force ◽  
Raw Materials ◽  
Volume Density ◽  
Raw Material ◽  
Rice Seedlings ◽  
Molding Machine ◽  
The Cost

As the late processing of rice straw may consume the cost and pollute the environment, this paper put forward a method to use the rice straw, namely, the rice straw is used as the raw material for making seedling trays. The process of seedling tray production was designed, and the method of obtaining raw materials and steps of seedling tray production were introduced. In addition, the overall structure, transmission system and the forming mold of the pneumatic molding machine were also designed and produced. Next, the seedling trays were made by using the production line to analyze the characteristics of the rice straw seedling strays. The study was intended to explore the rules about the influence of moisture content on the characteristics of the seedling strays. As the moisture content of the seedling trays increased, the seedling trays expanded, increasing the volume, density and mass. However, the ultimate tension and shear force borne by the seedling stray decreased along with the increase of moisture content. It could be known from the analysis that: rice straw seedling trays could satisfy the needs of rice nursery. Compared with the traditional plastic seedling tray, the rice straw seedling tray can simplify the production process and provide natural nutrients for rice seedlings.

Sign in / Sign up

Export Citation Format

Share Document