• Transactions of the Korean hydrogen and new energy society
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• v.15 no.2
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• pp.119-128
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• 2004

DME(Dimethyl Ether) was directly produced from the synthesis gas using the slurry phase reactor. The catalyst for DME production prepared two types (A type; Cu:Zn:Al=57:33:10, B type; Cu:Zn:Al=40:45:15, molar ratio). It was evaluated for the effect of the reaction medium oil using the small size slurry phase reactor. DME production yield and the methanol selectivity decreased in the order: n-hexadecane oil> mineral oil> therminol oil. The long-term test of DME production was carried out using A and B type catalyst, and n-hexadecane oil and mineral oil, respectively. It was confirmed that the use of A type for the catalyst and n-hexadecane for the reaction medium oil was very useful for the viewpoint of the DME production form the synthesis gas.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2000.11a
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• pp.177-181
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• 2000

A lab-scale slurry reactor was developed for the treatment of contaminated sediments with polycyclic aromatic hydrocarbons (naphthalene, phenanthrene). In this system, range from 85 to 95% of PAHs with 2~3 rings were degraded within 11 days. Higher naphthalene degradation(94.05%) over phenanthrene degradation(87.07%) was probably due its higher solubility. Both compounds were not detected in aqueous phase after 7days and only 26.8% of naphthalene and 49.1% of phenanthrene were biodegraded. Removal TPH(Total Petroleum Hydrocarbon) concentration in solid after 11 days of treatment was 46%.

• Journal of Korea Soil Environment Society
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• v.2 no.3
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• pp.23-30
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• 1997

The purpose of this study was to evaluate effects of solids content and mixing speed in treatment of petroleum hydrocarbon contaminated soils using a slurry-phase bioreactor. Performance results on slurry-phase bioremediation of diesel fuel contaminated soil were generated at the bench-scale level. The fate of TPH(Total Petroleum Hydrocarbon) was evaluated in combination with biological treatment. Abiotic and biotic fate of the TPH were determined using soil not previously exposed to compounds in diesel fuel. The reactor volume for given throughput can be reduced by maximizing the solids content. Applications of 50% and 20% solids content(dry weight basis) were showed a little difference(57.5% : 61.6%) in biological TPH removal rate each other. Mixing and particle suspension are critical to desorption and biological degradation. In this standpoint, this study was performed using two mixing speed. When the reactor was operated at 70rpm, it had a better result in the particle suspension and TPH removal rate than the reactor with mixer rotated at 20rpm. In the reactor applied 20rpm, it was resulted in failure of particle suspension.

• Journal of Korean Society for Atmospheric Environment
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• v.12 no.4
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• pp.449-457
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• 1996

The main purpose of this study was to investigate sulfur dioxide removal performance of flue gas desulfurization system utilizing a Spray Absorption/Drying Reactor. In this system, the size of droplets was considered the most significant factor and tested using a PDA system. Lime slurry flow rate, operating temperature, calcium/sulfur (Ca/S) ratio and applied air pressure were selected as major operation variables and tested/analyzed in terms of system performance. The results are as follows. 1. The $SO_2$ removal efficiencies were 49%, 74%, 85% for Ca$(OH)_2$ slurry flow rate of 10, 20, 30 ml/min, which implies that the increase of slurry flow rate improves removal efficiency. The optimum slurry flow rate in this study was, however, considered 20 ml/min because of constraints of system troubles and absorbent utilization. 2. As Ca/S ratio increased, $SO_2$ removal efficiency was observed to increase. 3. As air pressure, at the atomizing nozzole, increased from 3 to 5 $kg/cm^2, SO_2$ removal efficiency increased from 74% to 80%, because of droplet size reduction due to pressure increase during atomizing process and the increase of surface area, helping mass transfer between gas and liquid phase.

• Applied Chemistry for Engineering
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• v.16 no.5
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• pp.712-718
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• 2005

This research was conducted to evaluate the effect of recycled-water addition on the treatment of coar tar-contaminated soil with slurry phase bioreactor. A bench-scale slurry phase bioreactor was maintained to optimize the microbial growth. Silty loam soil was used for this research. Concentrations of coal tar and 14 target PAHs (Polyunclear Aromatic Hydrocarbons) in the soil were determined with gas chromatography. Addition of recycled-water to slurry phase bioreactor was not significantly increased the removal efficiency of 2000 mg coar tar/kg. However, it significantly increased the removal efficiency of 20000 mg coar tar/kg. In 20000 mg coar tar/kg, the first order kinetic constant and the removal efficiency of the reactor with recycled-water addition were 2.5 and 2.0 times higher than those of the reactor without recycled- water addition. Coar tar in the slurry phase bioreactor was removed in 3.8~16.0% by vaporization and biodegraded in 84.0~96.2%. Removal efficiency of 3-ring compounds was high as 92.2~99.7% in the case of recycled-water addition. However, removal efficiencies of 3 and 4-ring compounds were low as 0~30%.

• Journal of Animal Environmental Science
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• v.4 no.2
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• pp.137-147
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• 1998

This study was carried out to find deodorization effect of swine-slurry by addition of phototrophic bacteria(PTB). The pilot-scale reactors operation conditions was designed by the inoculum amounts of PTB and light-conditions. Treatment conditions was divided into 3 types; 106 MPN/ml$.$Dark(T-1), 108 MPN/ml$.$Dark(T-2), 108 MPN/ml$.$Natural light(T-3). The changes of the concentration of volatile fatty acids(VFAs), hydrogen sulfide(H2S), ammonia (NH3) and odor intensity were analyzed during the treatment period(35 days). From results of this study, the maximum intensity of odor in the headspace of the reactor T-1 was 4.82 and T-2, T-3 was 2.63, respectively. In swine-slurry of reactors used, it almost took 10 days until to be stabilized with solid and liquid phase. Intensity of odor in headspace was mainly derived from the liquid phase. The PTB inoculum method to swine-slurry was very effective in reduction of VFAs, H2S and Sulfate-reducing bacteria(SRB) concentration. Expecially, It was interested in reverse growth behaviour of SRB and PTB in these conditions.

• Journal of the Korean Applied Science and Technology
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• v.19 no.4
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• pp.251-257
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• 2002

Liquid-phase methanol synthesis via methyl formate using coal-derived syngas was carried out in a bench-scale(diameter 173 mm and dispersion height 1200 mm) slurry bubble column reactor(SBCR) Under the condition of $180^{\circ}$. 61 atm, 30 L/min, $H_{2}$/CO=2 and a slurry mixture of 2 kg of copper chromite and 0.5 kg of $KOCH_{3}$ suspended in 14 L of methanol, the per pass conversions of syngas is 6 %, maximum concentration of methyl formate 3.088 mol% and maximum synthesis, rate of methanol 0.8 gmole/kg ${\cdot}$ hr. It is a significant evidence that copper chromite powder as heterogeneous catalyst didn't active for the hydrogenolysis of methyl formate to methanol, resulting copper chromite powder was not efficiently suspended in a slurry mixture. To enhance the hydrogenolysis of methyl formate in liquid-phase methanol synthesis process, the designed SBCR have need to use the higher specific gravity solvent and/or decrease the catalyst particle size.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.50.1-50
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• 2001

Dynamic optimization with partially structured model in a slurry-phase HDPE reactor is implemented by the modified hierarchical dynamic optimization. Optimal trajectories of MI and density of HDPE are calculated as controlled variables and optimal profiles of the concentrations of ethylene, hydrogen and comonomer are calculated as manipulated variables in dynamic optimization. MI, density, the concentrations of ethylene, hydrogen and comonomer are used as controlled variables and flow rates of ethylene, hydrogen and comonomer are sued as manipulated variables in control implementation. Two-level hierarchical method is applied in dynamic optimization to reduce computation time. In the upper level formulation ...

• Asian-Australasian Journal of Animal Sciences
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• v.5 no.2
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• pp.199-215
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• 1992

Sources of organic waste materials for aerobic and/or anaerobic degradation, or for composting of solid wastes in Germany were estimated. The basic microbiology and the energetics of these processes were compared with special emphasis on anaerobic degradation, for which a general degradation scheme of carbohydrates is presented. Advantages of anaerobic over aerobic treatment processes are pointed out and conditions for maintaining a highly stable anaerobic process as well as producing a sanitized, hygienic product are discussed. Reactor systems suitable for efficient treatment of wastes with a high or low proportion of suspended solids are principally compared and results of laboratory studies on the degradation of several wastes and animal manures summarized. Finally, a piggery slurry treatment factory for an ultimate slurry processing to obtain a dry fertilizer and a harmless, disposable liquid, as it is in operation in Helmond/Holland, is presented and preliminary process data are presented.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.5
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• pp.949-957
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• 2000

This study investigates the remediation of the phenol or PNP(p-Nitrophenol) contaminated soils in a slurry reactor by a pure culture, P-99. The application of a pure culture for the phenol decontamination make the degradation rate three times faster than that of the mixed activated sludge. The destruction of 300 mg/L phenol was completed in 26 hours. As 1 mg of phenol was added, 0.1457 mg of microorganism was grown in the medium. The pure culture could not utilizes PNP, one of the xenobiotics, as a growth substrate. When the bacteria was induced by phenol enrichment medium. PNP could be effectively transformed with cometabolic process. The induction of the bacteria requires 1 mg of phenol for the destruction of 0.027 mg PNP. When PNP concentration in the medium contained phenol and PNP increased. the degradation rate of phenol was decreased. The degradation rate of phenol and PNP in the slurry reactor was about two times faster than in the reactor without slurry because of higher dissolved oxygen supply in the aqueous phase and adsorption on the surface of the soil.