• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.321-324
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• 2009

Upgrading of pyrolysis wax oil has been conducted in a continuous fixed bed reactor at $450^{\circ}C$, 1hour, LHSV 3.5/h. The catalytic degradation using HZSM-5 catalyst are compared with the thermal degradation and also was studied with a function of experimental variables. The raw pyrolysis wax oil shows relatively high boiling point distribution ranging from around $300^{\circ}C$ to $550^{\circ}C$, which has considerably higher boiling point distribution than that of commercial diesel. The product characteristic from thermal degradation shows a similar trend with that of raw pyrolysis wax oil. This means the thermal degradation of pyrolysis wax oil at high degradation temperature is not sufficiently occurred. On the other hand, the catalytic degradation using HZSM-5 catalyst relative to the thermal degradation shows the high conversion of pyrolysis wax oil to light hydrocarbons. This liquid product shows high gasoline range fraction as around 90% fraction and considerably high aromatic fraction in liquid product. Also, in the catalytic degradation the experimental variable such as catalyst amount and reaction temperature was studied.

• New & Renewable Energy
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• v.5 no.4
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• pp.52-58
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• 2009

Upgrading of pyrolysis wax oil using HZSM-5 catalyst has been conducted in a continuous fixed bed reactor at $450^{\circ}C$, 1hour, LHSV 3.5/h. The catalytic degradation was studied with a function of catalyst amount and reaction temperature. The raw pyrolysis wax oil shows relatively high boiling point distribution ranging from around $300^{\circ}C$ to $550^{\circ}C$, which has considerably higher boiling point distribution than that of commercial diesel. The catalytic degradation using HZSM-5 catalyst shows the high conversion of pyrolysis wax oil to light hydrocarbons. The liquid product obtained shows high gasoline range fraction as around 90% fraction and considerably high aromatic fraction in liquid product. Here, the experimental variable such as catalyst amount and reaction temperature was influenced on the product distribution.

• Journal of Environmental Science International
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• v.11 no.4
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• pp.375-382
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• 2002

The total hydrocarbon distribution of oil products obtained from the pyrolysis of four kinds of mixtures of polyethylene-polystyrene waste has been studied by multidimensional chromatography(high performance liquid chromatography followed by capillary gas chromatography)/mass spectrometry. Saturated, unsaturated and aromatic hydrocarbons in oil products were selectively pre-separated according to structural groups by HPLC and the weight fraction of each group was estimated by analysis of each component using GC-FID response factors. The hydrocarbon distribution of aliphatic fraction consists of $C_{5}$ to $C_{25}$ saturated and unsaturated hydrocarbons. And that of aromatics fraction consists of benzene, toluene, xylene, styrene, propenyl benzene, naphthalene, and some of derivatives. Pyrolysis temperature did not affect the ratio of total weight fraction of aliphatic over aromatic hydrocarbon distribution in case of PS only and PE-PS mixtures (1:1 and 1:4 wt. ratio) as a feed while affected the ratio of total wt. fraction in case of PE only. The optimal temperature for the maximum oil production was $600^{\circ}C$ for pyrolysis of PS and 1:1 and 1:4 mixtures of PE and PS. The optimal condition for aromatic recovery was $600^{\circ}C$ with 1:1 mixture of PE and PS. In this condition, aromatic was produced up to 90% of total oil product. The maximum yield of toluene, xylene, styrene, and propenyl benzene were 8.6, 8.9, 51.0 and 7.4% of feed for pyrolysis PS at $700^{\circ}C$, respectively. However, only 1.3% naphthalene was recovered at $700^{\circ}C$ with 1:1 PE:PS(by wt.).

• New & Renewable Energy
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• v.2 no.2 s.6
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• pp.118-125
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• 2006

The target of this work was the process development of demonstration plant to produce the high quality alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70 t/y and the pilot plant of 360 t/y had been developed. Main research contents in this step were the process performance test of pilot plant of 360 ton/year and the development of demonstration plant of 3,000 t/y, which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/y showed about 80% yield of liquid product, which was obtained by both light gas oil(LGO) and heavy gas oil(HGO), The boiling point range distribution of LO product that was mainly consisting of olefin components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

• Clean Technology
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• v.29 no.4
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• pp.262-271
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• 2023

Globally, the amount of waste plastics has been occurring to environmental problems. As a result, it is necessary to research methods that utilize waste plastic pyrolysis oil (WPPO) produced by pyrolysis. One such method being studied is utilizing WPPO as a naphtha feedstock. In this study, five types of WPPO were analyzed to determine whether they can be used as raw materials for naphtha. Because of their wide boiling point range, the WPPOs were fractionated into light and heavy fractions through vacuum distillation, and the separation and purification techniques were analyzed using GC-VUV to determine the content of paraffin, olefin, and other compounds. All WPPOs showed high olefin content regardless of the source and fraction. Aromatic and paraffin content varied depending on the source, and oxygen and other compounds also varied significantly by source and fraction. In addition, the light fraction showed a carbon distribution similar to that of naphtha, whereas the heavy fraction showed a carbon distribution of C₁₁ ~ C₁₄. In conclusion, additional processes and raw material selection are required to utilize waste plastic pyrolysis oil as a raw material for naphtha.

• Clean Technology
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• v.25 no.2
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• pp.168-176
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• 2019

Spent coffee is one of biomass sources to be converted into bio-oil. However, the bio-oil should be further upgraded to achieve a higher quality bio-oil because of its high oxygen content. Deoxygenation under hydrotreating using different catalysts (catalytic hydrodeoxygenation; HDO) is considered as one of the promising methods for upgrading bio-oil from pyrolysis by removal of O-containing groups. In this study, the HDO of spent coffee bio-oil, which was collected from fast pyrolysis of spent coffee ($460^{\circ}C$, $2.0{\times}U_{mf}$), was carried out in an autoclave. The product yields were 72.16 ~ 96.76 wt% of bio-oil, 0 ~ 18.59 wt% of char, and 3.24 ~ 9.25 wt% of gas obtained in 30 min at temperatures between $250^{\circ}C$ and $350^{\circ}C$ and pressure in the range of 3 to 9 bar. The highest yield of bio-oil of 97.13% was achieved at $250^{\circ}C$ and 3 bar, with high selectivity of D-Allose. The carbon number distribution of the bio-oil was analyzed based on the concept of simulated distillation. The $C_{12}{\sim}C_{14}$ fraction increased from 22.98 wt% to 27.30 wt%, whereas the $C_{19}{\sim}C_{26}$ fraction decreased from 24.74 wt% to 17.18 wt% with increasing reaction time. Bio-oil yields were slightly decreased when the HZSM-5 catalyst and dolomite were used. The selectivity of CO was increased at the HZSM-5 catalyst and decreased at the dolomite.

• Resources Recycling
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• v.17 no.6
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• pp.50-56
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• 2008

A polypropylene fraction collected from the stream of post-consumer plastics was pyrolyzed. The aim of this study is to observe the dependence of yield of BTEX-aromatics normally used as solvent on the reaction temperature. To reach the goal, three experiments were carried out at different temperature between 650 and $700^{\circ}C$, using a fluidized bed reactor that shows an excellent heat transfer. In the experiments, product gases were used as a fluidizing medium to maximize the amount of BTEX-aromatics at fixed flow rate and feed rate during the pyrolysis. Oil, gas and char were obtained as product fractions. Product gases were analyzed with GCs(TCD, FID) and with a GC-MS system for qualitative analysis. For an accurate analysis of product oil, the product oil was distilled under vacuum, and separated the distillation residues from oil fractions that were actually analyzed with a GC-MS system. As the reaction temperature went higher, the content of BTEX-aromatics increased. The maximal yield of BTEX-aromatics was obtained at $695^{\circ}C$ with a value of about 30%. The main compounds of product gas were $CH_4$, $C_2H_4$, $C_2H_6$, $C_3H_6$, $C_4H_{10}$ and the product gas had an higher heating value about 45MJ/kg. It could be used as a heat source for a pyrolysis plant or for other fuel applications.

• New & Renewable Energy
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• v.18 no.4
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• pp.12-21
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• 2022

The pyrolysis characteristics of high-density polyethylene (HDPE), low-density polyethylene (LDPE), and polypropylene (PP) were analyzed numerically using a 1D plug flow reactor (PFR) model. A lumped kinetic model was selected to simplify the pyrolysis products as wax, oil, and gas. The simulation was performed in the 400-600℃ range, and the plastic pyrolysis and product generation characteristics with respect to time were compared at various temperatures. It was found that plastic pyrolysis accelerates rapidly as the temperature rises. The amounts of the pyrolysis products wax and oil increase and then decrease with time, whereas the amount of gas produced increases continuously. In LDPE pyrolysis, the pyrolysis time was longer than that observed for other plastics at a specified temperature, and the amount of wax generated was the greatest. The maximum mass fraction of oil was obtained in the order of HDPE, PP, and LDPE at a specified temperature, and it decreased with temperature. Although the 1D model adopted in this study has a limitation in that it does not include material transport and heat transfer phenomena, the qualitative results presented herein could provide base data regarding various types of plastic pyrolysis to predict the product characteristics. These results can in turn be used when designing pyrolysis reactors.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.523-526
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• 2006

The target of this work was the process development of demonstration plant to produce the high quailty alternative fuel oil by the pyrolysis of mixed plastic waste. In the first step of research, the bench-scale units of 70t/y and the pi lot plant of 360 t/v had been developed. Main research contents in this step were the process performance test of pilot plant ot 360ton/year and the development of demonstration plant of 3 000 t/y which was constructed at Korea R & D Company in Kimjae City. The process performance of pilot plant of 360 t/v showed components in PONA group appeared at between that of commercial gasoline and kerosene. On the other hand, HO product was mainly paraffin and olefin components and also appeared at upper temperature distribution range than commercial diesel. Gas product showed a high fraction of $C_3\;and\;C_4$ product like LPG composition, but also a high fraction of $CO_2$ and CO by probably a little leak of process.

• Korean Chemical Engineering Research
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• v.50 no.4
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• pp.672-677
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• 2012

Lipids in microalgal biomass were recovered by using pyrolysis method. The pyrolysis experiments of two Chlorella sp. KR-1 samples, which have triglyceride contents of 10.8% and 36.5%, respectively were carried out at $600^{\circ}C$ to investigate the effects of lipid contents in the cells on the reaction characteristics. The conversion and liquid yield of the lipid-rich sample were higher than those of the lipid-lean sample since its carbon to hydrogen ratio was low. There were low molecular weight organic acids, ketones, aldehydes and alcohols in the liquid products from both KR-1 samples, but the pyrolysis oil of the lipid-rich sample was abundant in free fatty acids, particularly palmitic acid, oleic acid and stearic acid while the content of nitrogen containing organic compounds was low. The microalgal pyrolysis oil had two layers composed of the light hydrophobic fraction and the heavy hydrophilic fraction. The light fraction might be originated from triglycerides and the heavy fraction might be from carbohydrates and proteins. In the light fraction of the liquid products, there were considerable linear alkanes such as pentadecane and heptadecane as well as free fatty acids, implying that deoxygenation reaction including decarboxylation was occurred during the pyrolysis. The yield of the liquid products from the pyrolysis of the KR-1 sample having triglyceride content of 36.5% was 56.9% and the light fraction in the liquid products was 68.2%. Also more than 80% of the light fraction was free fatty acids and pure hydrocarbons, thus showing that most triglycerides could be extracted in the form of suitable raw materials for biofuels.