• 한국연소학회:학술대회논문집
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• 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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• pp.29-32
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• 2014

The practical route for disposal of sewage sludge becomes energy recovery by combustion after its ocean dumping is banned in 2012 in Korea. Due to the high moisture content, however, sewage sludge is required to be dried before transport and combustion. In this study, pyrolysis and combustion characteristics of dried sewage sludge was investigated in a small-scale fixed bed reactor in order to provide fundamental data for energy recovery of the fuel. As the first step of combustion, the primary products of pyrolysis were analyzed in a fixed bed reactor for the condensable volatiles (tar), non-condensable gases, and char. For the combustion characteristics, another fixed bed reactor was constructed to monitor the weight and temperature of the fuel particles during ignition and combustion under different air flow rates. The test results were used to derive the ignition and burning rates.

• Carbon letters
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• 제4권2호
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• pp.74-78
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• 2003

Four kinds of plasma blacks were prepared by plasma pyrolysis under various metallic catalysts coated on honeycomb, and investigated the catalytic effect on the characteristics of the plasma blacks prepared under plasma pyrolysis condition. Pt, Pt-Rh, and Pd catalysts were employed as active materials to prepare the plasma blacks. In the experimental range studied, the metallic catalysts influenced on surface area, particle size, surface oxygen content and electrical conductivity of the plasma blacks prepared. It was showed that more dense particle of plasma blacks were prepared under existence of metallic catalysts. Presence of the metallic catalyst reduces the electrical resistivity of plasma blacks due to the decrease in the amount of oxygen functional groups. The highest electrical conductivity of plasma black was observed in the Pt catalyst and then followed by those Pt-Rh, Pd and bare cordierite honeycomb.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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• pp.105.1-105.1
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• 2011

To enhance the performance of photovoltaic a-Si:H solar cells with a hybrid-type light absorbing structure of single crystal silicon nanoparticles (Si NPs) in a-Si:H matrix, single crystal Si NPs were produced by laser pyrolysis. The Si NPs were synthesized by $SiH_4$ gas decomposition using a $CO_2$ laser. The properties of Si NPs were controlled by process parameters such as $CO_2$ laser power, reactive gas pressure, and $H_2/SiH_4$ gas flows. The crystalline properties and sizes of Si NPs were analyzed by High Resolution Transmission Electron Microscopy (HRTEM). The sizes of Si NPs were controllable in the range of 5-15 nm in diameter and the effects of process parameters of laser pyrolysis were systematically investigated.

• 공업화학
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• 제16권1호
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• pp.68-73
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• 2005

층상 실리케이트를 주형으로 이용하여 실리케이트의 층간에 pyrolized fuel oil (PFO)를 삽입하고 열분해시킨 후 실리케이트 골격을 용출 제거함으로써 다공성 층상카본을 제조하였다. 층상카본의 입자모양은 층상실리케이트 주형과 유사한 판상 형태이며, d-spacing은 0.78~0.82 nm로 일정한 값을 나타내었다. 실리케이트와 PFO의 혼합비율과 열처리 온도, 열처리 시간에 따른 비표면적은 $30{\sim}576m^2/g$로 크게 다른 값을 나타내었다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집 Vol.3 No.2
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• pp.1060-1062
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• 2002

Spherical and dense BAM phosphor particles were prepared by spray pyrolysis. The key idea of dense BAM particles is to lead gelation in droplets, which was successfully achieved by using the aluminum polycation as the precursor solution for the spray pyrolysis. The BAM phosphor particles prepared by spraying the aluminum polycation solution have completely spherical shape and dense structure. When directly applied to make phosphor film on the glass by the screen-printing method, the prepared spherical BAM phosphor particles showed better packing density and surface morphology than that of commercial one, which has irregular shape and large particle size. It was also found that the thermal degradation in the photoluminescence intensity for dense and spherical BAM particles was less than that of commercial one.

• 한국세라믹학회지
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• 제45권2호
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• pp.126-131
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• 2008

In this study, we prepared zirconia gel by the sol-gel method and investigated its photoluminescence properties by varying pyrolysis temperature. The addition of acetic acid into a Zr-alkoxide solution resulted in forming the bidentate ligands with Zr ions and producing a stable gel. At the pyrolysis temperature of $350^{\circ}C$, the zirconia nanocrystals with tetragonal structure gradually appeared in the gel. The PL intensity of the zirconia gel increased with increasing the pyrolysis temperature up to $350^{\circ}C$, but decreased above the temperature. Concurrently, its PL peak wavelength continuously shifted from ${\sim}440\;nm$ to ${\sim}550\;nm$ with the temperature. The PL characteristics of the zirconia gels were closely associated with decomposition of residual organic groups, the formation of the zirconia nanocrystals, and the tetragonal to monoclinic phase transformation.

• 한국환경보건학회:학술대회논문집
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• 한국환경보건학회 2002년도 춘계 국제 학술대회
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• pp.84-90
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• 2002

In 1995 we licensed pyrolysis gas melting technology of indirect heating type (using kiln) from Siemens AG, and built its demonstration facility in 1998 at Clean-Park-East of Fukuoka City to demonstrate the technology for municipal solid waste (MSW). In 1997 we were awarded an order from Kanemura Co., Ltd. to build a pyrolysis gas melting and power generation plant, specifically for treating residue from car shredder. The latter was launched in 1998, and is currently in commercial operation. The operation of these plants have proven the following facts. (1) The system is capable for performing a stable operation with a wide variety of waste. (2) Pyrolysis is achieved steadily regardless of the variation in the quality of waste. (3) The system can be operated under low excess air ratio (1.2∼1.3). (4) The concentration of dioxins at the furnace outlet is 0.062ng-TEQ/㎥$\_$N/, and 0.002ng-TEQ/㎥$\_$N/, at the stack. (the value is corrected to dryO$_2$ 12％) (5) The purity of recovered metals exceeds 90%.

• Progress in Superconductivity
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• 제6권2호
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• pp.124-128
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• 2005

Homogeneous and fine powders for Bi-2223 tape were prepared by ultrasonic spray pyrolysis (SP) method from an aqueous solution of metal nitrates. Bi-2223 precursor powders were synthesized with various solutes concentration and pyrolysis temperature. The synthesized precursor powders had a narrow particle size distribution and an average particle size was $\~{\cal}um$. The reactivity of precursor powder by SP method is very high, attributed to the fine and narrow particle size distribution. Bi-2223/Ag tape was prepared using PIT method and followed by various sintering conditions. The precursor powder by SP method promoted a very quick formation of the Bi-2223 phase for short sintering time while the secondary phase such as large AEC phase and $Ca_2PbO_4$ were minimized for SP tapes.

• The Korean Journal of Ceramics
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• 제4권3호
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• pp.199-203
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• 1998

$Pb(Zr, Ti)O_3$ (Pb:Zr:Ti=1:0.52:0.48) thin films were prepared on single crystal MgO(100) substrates by dipping-pyrolysis process using a solution of constituent metal naphthenates as starting materials. The solution was spin-coated onto substrate and the precursor films were pyrolyzed at $200^{\circ}C$ in air or at $200^{\circ}C$ in argon for 1, 2, 5 and 24h, followed by final heat treatment at $750^{\circ}C$. For all the films, highly (h00)/(00l)-oriented Pb$Pb(Zr, Ti)O_3$ thin films with smooth surfaces and crack-free were obtained, whereas thin film pyrolyzed in air for 24 h exhibited polycrystalline character. According to the pole-figure analysis, epitaxy of the product films was found to depend on pyrolysis atmosphere.

• Carbon letters
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• 제2권2호
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• pp.91-98
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• 2001

Porous carbons have been prepared from different parts of banana stems using two different routes, viz., by pyrolysing the mass at different temperatures as well as by treating the dried mass with chemicals followed by pyrolysis. The pyrolysis behaviour of all these materials has been studied up to $1000^{\circ}C$. Samples treated with acids exhibit more increase in surface area as compared to those treated with alkalies or salts. Analysis of BET surface area shows that the carbon prepared at low temperature shows mixed porosity, i.e., micro and mesopores. Samples heated to high temperature above $700^{\circ}C$ show decrease in macroporosity and increase in microporosity. Liquid adsorption studies have been made using methylene blue and heavy oil. The activated carbons so prepared exhibit higher oil adsorption mainly in the macro and mesopores.