• Polymer(Korea)
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• v.32 no.2
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• pp.157-162
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• 2008

To investigate the characteristics of pyrolysis for LDPE, LLDPE and HDPE, the low temperature pyrolysis was carried out in the range of 425 to $500^{\circ}C$ for 35 to 65 min. The liquid products formed during pyrolysis were classified into gasoline, kerosene, light oil and wax according to the distillation temperatures based on the petroleum product quality standard of Korea Petroleum Quality Inspection Institute. TGA experiments for three PE samples showed that the onset temperature of pyrolysis increased with increasing heating rate, and the onset temperature of pyrolysis at a fixed heating rate was in the order of LDPE$475^{\circ}C$. Yields of gasoline and kerosene were highest at $450^{\circ}C$, 65 min and decreased slightly at above $475^{\circ}C$.

• Clean Technology
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• v.8 no.1
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• pp.1-9
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• 2002

Mild pyrolysis of four different coals (two bituminous coals and two Korean antracite) was investigated. Desulfurization characteristics, weight loss and variation of heating values were studied. As operating variables of experiment, pyrolysis temperature($350{\sim}550^{\circ}C$), pyrolysis time(5~20 min.) and particle size(0~3.55mm) were examined. The maximum sulfur removal rate of bituminous coal and anthracite were 38% and 28%, respectively. The optimum mild pyrolysis conditions were 10~15 min for pyrolysis time and $450{\sim}550^{\circ}C$ for pyrolysis temperature. The mild pyrolysis was effective to reduce organic sulfur content. Heating values of char per mass after pyrolysis increased about 5% compared to raw coal. The effect of coal particle size on the desulfurization was not observed.

• Resources Recycling
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• v.14 no.2
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• pp.28-32
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• 2005

By using thermal decomposition method, the preliminary experiments for recovery of metallic Ga from GaAs scraps produced in the manufacturing of compound semiconductors were carried out in laboratory(200 g/batch) scales. From these results, decomposition appratus with packed tower was constructed in commercial scale(30 kg/batch). The decomposition rate of GaAs increased with raising decomposition temperature, but the yield of Ga decreased over 1000$^{\circ}C. As a result, the optimum decomposition temperature was 1000~1050$^{\circ}C when the pressure of decomposition reactor was 2~2.5${\times}10^{-2} mmHg, and the yield of Ga was about 89 wt.%. The commercial decomposition apparatus was designed with packed tower because the partial pressure of As in vapor state was not reduced even if the temperature of As vapor was decreased. The recovery yield of Ga from GaAs scraps in large scale experiment showed 99%.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2001.11a
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• pp.67-72
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• 2001

오랜 동안의 경험으로부터 조건설정이 표준화되어 있는 석유화학공업과는 달리 정밀화학공업에 있어서는 대상이 되는 공정의 반응조건 등을 제조자 스스로 결정해야 하는 경우가 많다. 또한, 취급하는 화학물질의 열분해 또는 반응위험성에 대한 위험성평가는 물론 물질안전자료(MSDS)도 확보되지 않은 상태에서 취급되는 경우가 많아 폭발ㆍ화재로 인한 중대재해의 잠재적 위험성이 매우 높은 상태이다.(중략)

• Applied Chemistry for Engineering
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• v.22 no.6
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• pp.636-641
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• 2011

Since the mid-1990s, the number of fires continue to increase and the size has been also larger. However, the pyrolysis and combustion characteristics of the various species of the medium such as fallen leaves, herbaceous plants, conifers and broadleaf trees have scarcely been studied. In this paper, we investigate the pyrolysis and combustion of the typical domestic needle-leaf tree of Pinus densiflora and thinning-out tree by thermogravimetric analysis (TGA). Pinus densiflora was ignited at $200^{\circ}C$ and pyrolysis from $230^{\circ}C$. In case of thinning-out tree was ignited and pyrolysis at $180^{\circ}C$ and $205^{\circ}C$, respectively. The values of activation energy for pyrolysis were increased as the conversion efficiency increasing from 10% to 80%, whereas the values was decreased during combustion.

• Journal of Energy Engineering
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• v.14 no.2 s.42
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• pp.159-166
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• 2005

In Korea, although the generation of waste plastic has been increasing, the rate of recycling is considerably low and moreover, there is no suitable method for the treatment of waste plastics. However, pyrolysis, which is appropriate for the treatment of highly polymerized compounds, such as plastics, has recently gained much interest. In this study, a property of the products from the pyrolysis of mixed waste plastics, with a possible practical use for the recycling oil produced, were assessed. First of all, in order to investigate the pyrolysis characteristic of waste plastics, TGA (Thermogravimetric analysis) and DCS (Differential Scanning Calorimetry) were performed on a number of different plastics, including PP, LDPE, HDPE, PET and PS, as well as others. According to the result, it appeared that PP was the most efficiently pyrolyzed by changing the temperature, followed by LDPE, HDPE, PET, PS and the other plastics, in that order. From the results, the optimum conditions f3r pyrolysis were set up, and the different waste plastics pyrolyzed. The recycling oil produced from the flammable gases generated during the pyrolysis was com-pared with fuel oil by an analysis using the petroleum quality inspection method on KS(Korea industrial Standard). The results of the analysis showed the recycling oil was of a similar standard to fuel oil, with the exception of the ignition point, with a quality somewhere between that of paraffin oil and diesel fuel. With respect to these results, the quality of the recycling oil produced by the pyrolysis of waste plastics was suf-ficient for use as fuel oil.

• Journal of Korean Society of Environmental Engineers
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• v.27 no.2
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• pp.130-137
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• 2005

This research programme include investigation of the adsorption behavior of heavy metals and VOCs by Pyrolysis char for using landfill cover material. The volatile potions in the sludge gasified during the pyrolysis period and gave birth to porosity throughout the matrix. The result of the ad/desorption experiment of nitrogen to find out the formation of some pore by the gasification of the volatile matter, we can certify that the pyrolysis char($14.56\;m^2/g$) has increased twice more than the organic wasted sludge($6.68\;m^2/g$) in specific surface area. The pyrolysis char has the adsorption characteristic of medium type of Type II and V in BDDT classification, and showed a little micro pore. In the adsorption experiment of ethylbenzene and toluene, as a result of applying the Freundlich adsorption isotherms, the pyrolysis char was higher in the adsorptivity of ethylbenzene and toluene than the granite and the organic wasted sludge. The results of the heavy metal adsorption test for the char indicated that it had some ability of adsorption. It is suggest that pyrolysis char has some advantages for utilizing as landfill covers because the pyrolysis char can adsorb/absorb hazardous substances from the landfill sites and inhibit the ground water and soil contamination.

• Resources Recycling
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• v.23 no.6
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• pp.47-53
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• 2014

Effective treatment and energy conversion technologies are necessary due to the ban of the dumping of organic waste including the sewage sludge. In this study, the kinetics of pyrolysis and combustion were derived in a TGA and thermobalance reactor, which is essential for thermal conversion of sewage sludge to energy. Three steps are shown for the pyrolysis in TGA and the different pre-exponential factors and activation energies are derived depending on the temperature range. Three models of gassolid reaction were applied to the reaction kinetics analysis for the combustion of sewage sludge char and shrinking core model was an appropriated model. Apparent activation energy and pre-exponential factor were evaluated and the effect of oxygen partial pressure was examined.

• Journal of the Korean Society of Propulsion Engineers
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• v.19 no.5
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• pp.15-21
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• 2015

The thermal decomposition characteristics of the ZPP(Zirconium/Potassium perchlorate), widely used as a primary charge of initiators, were investigated by differential scanning calorimetry(DSC). The DSC results with different heating rates were elaborated with AKTS-Thermokinetics software for the determination of the kinetic parameters of the thermal decomposition of ZPP. There was good agreement between the experimental and the simulation curves, based on the determined kinetic parameters, which indicates the validity of the kinetic description of the thermal decomposition process of ZPP.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.112.2-112.2
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• 2011

미곡종합처리장에서 발생되는 농업부산물인 왕겨는 대부분 퇴비의 재료로 활용되고 있으며, 수익성이 없는 것으로 알려져 있다. 근래에 화석자원의 고갈이 진행되면서, 왕겨, 볏짚을 포함한 농업부산물은 화석연료와 달리 재생이 가능하고 지속 가능한 자원으로 각광을 받고 있다. 바이오매스를 이용하는 신재생에너지 기술로는 생물학적, 열화학적, 물리적 변환 기술 등이 있다. 그중 열화학적 변환 기술은 반응시간이 짧고, 단위부피당 처리량이 높으며 공정상의 폐기물이 적은 장점을 지니고 있어 왕겨의 에너지 활용에 효율적인 기술로 알려져 있다. 왕겨의 열분해 가스화는 CO, $H_2$, $CO_2$, 및 $CH_4$ 가스가 주성분인 합성가스로 전환되는 것을 말하며, 생산된 합성가스는 가스엔진의 발전 연료로 사용될 수 있다. 본 연구에서는 농업부산물인 왕겨를 이용한 열분해 가스화기에서 발생된 합성가스를 정제한 후, 20kW급 가스엔진을 적용하여 합성가스 에너지 활용특성에 관하여 고찰하였다. 그 결과 왕겨의 열분해/가스화반응에 의해 발생된 합성가스를 가스엔진으로 안정적으로 공급하였으며,16kw의 전력이 생산되는 것으로 나타났다.