• Journal of the Korea Organic Resources Recycling Association
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• v.13 no.4
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• pp.79-88
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• 2005

The wastes generated in farming or fishing villages are mostly those of high moisture content or those once used for farming or fishing work, which require a complex process even for disposing of them alone, and moreover they have been recognized to cause a secondary side effects. The study thus is intended to conduct the basic character analysis and incineration test so as to develop the thermal decomposition furnace which will be optimal in disposing of the wastes generated from urban area that mostly have a high thermal energy or require a complex treatment process. And the subject included in the study, in addition, is to design and develop the furnace aimed at reducing the harmful ingredient as well as recycling the heat generated in the course of incineration.

• New & Renewable Energy
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• v.17 no.2
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• pp.40-49
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• 2021

This paper explains the development process of methane decomposition to hydrogen and carbon black using solar thermal energy. It also demonstrates the advantages and disadvantages of five different reactors for each development stage, including the reactor's experimental results. Starting with the initial direct heating type reactor, the indirect heating type reactor was developed through five modifications. The 40-kWth solar furnace installed at the Korea Institute of Energy Research was used for the experiment. In the experiment using the developed indirect heating reactor, an 89.0% methane to hydrogen conversion rate was achieved at a methane flow rate of 40 L/min, obtained at about twice the flow rate compared to previous advanced studies.

• Resources Recycling
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• v.9 no.6
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• pp.15-22
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• 2000

There are many intensive efforts to develop the recycling technologies of waste plastics in steel works to tackle the saving of resources and the protection of the natural environment. In this study, the thermogravimetric analyses for three kinds of plastics, the combustion experiments and the theoretical approach for calculating the flame temperature in the blast furnace had been performed to understand the behavior of plastics in the raceway. The thermal decompositions of plastics were studied using thermogravimetric analyzer under the atmospheric condition. The starting temperature of thermal decomposition and the maximum weight loss point were increased in proportion to the logarithmic values of heating rate. The combustion characteristics of plastics were simulated in a coke-bed combustor. The combustion efficiency of plastics was lower than that of pulverized coal. The oxygen enrichment was found out to be one of the useful methods to increase the combustibility of plastics in raceway. The maximum injection rate of plastics was calculated based on the flame temperature.

• Journal of Environmental Science International
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• v.19 no.5
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• pp.577-584
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• 2010

The generation of $TiO_2$ nanoparticles by a thermal decomposition of titanium tetraisopropoxide (TTIP) was carried out experimentally using a tubular electric furnace at various synthesis temperatures (700, 900, 1100 and $1300^{\circ}C$) and precursor heating temperatures (80, 95 and $110^{\circ}C$). Effects of degree of crystallinity, surface area and anatase mass fraction of those $TiO_2$ nanoparticles on photocatalytic properties such as decomposition of methylene blue was investigated. Results show that the primary particle diameter obtained from thermal decomposition of TTIP was considerably smaller than the commercial photocatalyst (Degussa, P25). Also, those specific surface areas were more than 134.4 $m^2$/g. Resultant $TiO_2$ nanoparticles showed improved photocatalytic activity compared with Deggusa P25. This is contributed to the higher degree of crystallinity, surface area and anatase mass fraction of $TiO_2$ nanoparticles compared with P25.

• Proceedings of the Korea Association of Crystal Growth Conference
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• 2000.06a
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• pp.179-193
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• 2000

Aluminium titanate (Al₂TiO5) with an excellent thermal shock resistant and a low the expansion coefficient was obtained by solid solution with MgO, SiO₂, and ZrO₂ in the Al₂TiO5 lattice or in the grain boundary solution through electrofusion in an arc furnace. However, these materials have low mechanical strength due to the presence of microcracks developed by a large difference in thermal expansion coefficients along crystallographic axes. Pure Al₂TiO5 tends to decompose into α-Al₂O₃ and TiO₂-rutile in the temperature range of 750-1300℃ that rendered it apparently useless for industrial applications. Several thermal shock tests were performed: Long therm thermal annealing test at 1100℃ for 100h; and water quenching from 950 to room temperature (RT). Cyclic thermal expansion coefficients up to 1500℃ before and after decomposition tests was also measured using a dilatometer, changes in the microstructure, thermal expansion coefficients, Young's modulus and strengths were determined. The role of microcracks in relation to thermal shock resistance and thermal expansion coefficient is discussed.

• New & Renewable Energy
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• v.17 no.1
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• pp.40-49
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• 2021

In this study, the optical properties, heat transfer capabilities and chemical reaction performance of a methane thermal decomposition reactor using solar heat as a heat source were numerically analyzed on the basis of the cavity shape. The optical properties were analyzed using TracePro, a Monte Carlo ray tracing-based program, and the heat transfer analysis was performed using Fluent, a CFD program. An indirect heating tubular reactor was rotated at a constant speed to prevent damage by the heat source in the solar furnace. The inside of the reactor was filled with a porous catalyst for methane decomposition, and the outside was insulated to reduce heat loss. The performance of the reactor, based on cavity shape, was calculated when solar heat was concentrated on the reactor surface and methane was supplied into the reactor in an environment with a solar irradiance of 700 W/㎡, a wind speed of 1 m/s, and an outdoor temperature of 25℃. Thus, it was confirmed that the heat loss of the full-cavity model decreased to 13% and the methane conversion rate increased by 33.5% when compared to the semi-cavity model.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.3 no.3
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• pp.249-256
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• 2005

Thermal decomposition and stabilization characteristics of the solid cake after the dissolution of nitrate of the lagoon sludge was investigated. Most of the nitrates were dissolved in the water and removed to the filtrate, but small amount of nitrates, calcium carbonate and uranium were remained in the solid cake. The solid cake was thermally decomposed in the muffle furnace at $900^{\circ}C$ for 5 hours. Uranium, which is in the lagoon 1, was stabilized with $NaNO_3$ decomposition to $Na_{2}O{\cdot}2UO_3$ form. For the lagoon 2, it is confirmed that CaO, which was created by thermal decomposition of the $Ca(NO_3)_2$ and $CaCO_3$, was transferred to $Ca(OH)_2$ in the air with water. Because it is known that $Ca(OH)_2$ is stable material, further additives did not need to the stabilization of the thermal decomposition of the lagoons.

• Journal of the Korean Ceramic Society
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• v.35 no.10
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• pp.1061-1069
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• 1998

The thermal instability of Al2TiO5 Ceramics was contrlled by solid solution with MgO SiO2 and ZrO2 through electrofusion in an arc furnace. The thermal expansion properties of Al2TiO5 composites show the hysteresis due to the strong anisotropy of The crystal axes of these material. These phenomena are ex-plained by the opening and closing of microcracks. The difference in microcracking temperatures e.g 587.6(ATG2), 405.9(ATG3) and 519.7$^{\circ}C$(ATG4) is caused by the difference in grain size and stabilizer type. The thermal shock behaviour under cyclic conditions between 750-1400-75$0^{\circ}C$ show no change in mi-crostructure and phase assemblage for all three stabilized specimens. After the thermal loading test at 110$0^{\circ}C$ for 100hrs. ATG1 and ATG2 materials decomposes completely to its components corundum and ru-tile in both cases. However with approximatelly 20% retention of the Al2TiO5 Thus in order to prevent decomposition of the stabilized material in the critical temperature range 800-130$0^{\circ}C$ it must be traversed within a short period of time.

• Journal of the Korean Applied Science and Technology
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• v.23 no.2
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• pp.147-152
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• 2006

The accidents occurred by unstable material which is easily exploded or burnt up were caused by heat and collision under the condition of relatively low temperature without oxygen, have been reported frequently. However, the amount of the unstable material is getting higher by development of fine ceramic research area even though its dangerous characteristic is disregarded. This research studied a heat stability and measured boiling point of various carpet material. Carpet has been used in home as well as general indoor usage. Now a day, carpet material which is hardly burnt has been on commercial, but its detailed unstable conditions is not mentioned. This research reports the measurement of the initial temperature of generation heat and heat-radiation change on differential scanning calorimeter (DSC). The DSC data of nylon bulked continuous filament (N-BCF) yam 100%, nylon (NY), poly propylene (PP), and a new material named polytrimethylene terephthalate (PTT) are studied and researched about the effect of them using TGA, furnace, and direct-burning experiment.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.5
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• pp.501-509
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• 2004

Unipolar diffusion charging of non-spherical particles was investigated for various particle shapes. We researched with TiO$_2$agglomerates produced by the thermal decomposition of titanium tetraisopropoxide (TTIP) vapor. TTIP was converted into TiO$_2$, in the furnace reactor and was subsequently introduced into the sintering furnace. Increasing the temperature in the sintering furnace, aggregates were restructured into higher fractal dimensions. The aggregates were classified according to their mobility using a differential mobility analyzer. The projection area and the mass fractal dimension of particles were measured with an image processing technique performed by using transmission electron microscope (TEM) photograph. The selected aggregates were charged by the indirect photoelectric-charger and the average number of charges per particle was measured by an aerosol electrometer and a condensation particle counter. For the particles of same mobility diameter, our results showed that the particle charge quantity decreases as the sintering temperature increases. This result is understandable because particles with lower fractal dimension have larger capacitance and geometric surface area.