• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.11a
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• pp.243-250
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• 2001

• Proceedings of the Korean Ceranic Society Conference
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• 2004.10a
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• pp.93.1-93.1
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• 2004

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1997.10a
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• pp.54-58
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• 1997

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1998.10a
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• pp.103-108
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• 1998

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 2001.05a
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• pp.63-70
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• 2001

• Journal of the Korean Society for Marine Environment & Energy
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• v.9 no.2
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• pp.72-78
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• 2006

Effect of organic loading rate on digester performance was evaluated under the conditions of same surface area/reactor volume ratio and different reactor diameter. At the low loading rate of $0.4\;kg\;COD/m^3{\cdot}d$, high rate of organic removal could be obtained regardless of reactor diameter. It can be estimated that reactor configuration can not affect reactor performance at the low loading rate. However, different performance depending on reactor diameter was observed at the organic loading rate of $6\;kg\;COD/m^3{\cdot}d$. That is, volatile acid accumulation and low COD removal efficiency was observed in reactor having 6.4 cm diameter, while volatile acid was not accumulated at all and high COD removal efficiency was observed in reactor having 3 cm diameter. Such a difference of reactor performance depending on reactor diameter can be explained that sludge bed can be fluidized by evolved gas bubble in narrow reactor while sludge bed can not be fluidized by evolved gas bubble only in wide reactor. At a high organic loading rate of $20\;kg\;COD/m^3{\cdot}d$, it can be judged that there is no relation between reactor configuration and reactor performance because all reactors showed very low COD removal efficiencies regardless of reactor diameter. Sludge bed fluidization is one of the most important factors in achieving efficient start-up of anaerobic digester. Narrow and tall type reactor is favorable condition for making sludge bed fluidization at a constant surface area/reactor volume ratio. Thus, it can be judged that reactor configuration and sludge bed fluidization have great influence to reactor performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.2
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• pp.90-96
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• 2018

Tracer experiments were carried out on two laboratory modes, "without media mode" and "with media mode", to examine the hydraulic characteristics of the anaerobic fluidized bed bioreactor (AFBR). For both configurations, a formula was derived for the hydraulics and data interpretation to obtain the actual characteristics of the reactor. The dispersion model is based on the assumption that carriers are non-reacting and the dispersion coefficient is constant. The model represents the one-dimensional unsteady-state concentration distribution of the non-reacting tracer in the reactors. The experimental results showed that the media increased the mixing conditions in the reactor considerably. For the reactor without media, in the range tested, the dispersion coefficient was at least an order of magnitude smaller than that of the reactor with media. Advective transport dominates and the flow pattern approaches the plug flow reactor (PFR) regime. The dispersion coefficient increased significantly as us, the superficial liquid velocity, was increased proportionally to 0.82cm/s. On the other hand, for the reactor with media, the flow pattern was in between a PFR and a completely mixed flow reactor (CMFR) regime, and the dispersion coefficient was saturated at us=0.41cm/s, remaining relatively constant, even at us=0.82cm/s. The dispersion coefficient depends strongly on the liquid Reynolds number (Re) or the particle Reynolds number (Rep) over the range tested.

• Journal of the Korean Chemical Society
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• v.24 no.4
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• pp.329-336
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• 1980

A domestic phosphogypsum was calcined in a batch type fluidized bed reactor at various reaction temperatures ranging 90∼180$^{\circ}$ without and with an alkaline additive amounting up to 5% of gypsum, and physical properties of the resultant products were compared following their characterization by X-ray diffraction pattern and DTA. It has been found that dehydration reactions were uniformly carried out in the fluidized bed reactor and only hemihydrate was obtained at 90$^{\circ}$ whereas at higher temperatures dehydration reaction progressed further. When gypsum was charged to the reactor preheated at over 140$^{\circ}$, a considerable degree of dehydration occurred before the reactant reached the initially set reactor temperature and in particular, at over 160$^{\circ}$ most of dehydration reaction was performed prior to the present reactor temperature. However, it has been found that gypsum mostly transforms into hemihydrate around the reactant temperature of 140$^{\circ}$ while transformation into anhydrite mostly occurs around $160^{\circ}C.$ When calcium hydroxide was added to gypsum in the reactor, the optimum physical properties of the calcined product were obtained at the weight ratio of $Ca(OH_2)/P_2O_5$ = 3.2.

• Journal of Environmental Health Sciences
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• v.24 no.1
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• pp.1-8
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• 1998

This study was carried to investigate the treatment characteristics of the phenol and catechol with an anaerobic fluidized bed reactor(AFBR) having a dimension of 9 cm i.d. and 1.25 m height. The reactor was operated at $35\pm 1\circ$C. The COD concentration of the effluent, the gas production rate and the composition of gas were measured to determine the performance of the AFBR as the hydraulic retention time(HRT) was decreased from 2 days to i day at 600 mg/l of the phenol and catechol concentration. Stable treatment of the phenol wastewater could be achieved with the AFBR at 18 days but the catechol wastewater couldn't be. At HRT 2 days, the phenol wastewater showed the COD reduction efficiency of 93% and the gas production of 2.7 l/day and the catechol wastewater was obtained the COD reduction efficiency of 82% and the gas production of 0.72 l/day. Also at HRT 1 day the phenol and catechol wastewater showed the COD reduction efficiency of 95% and 73% and the gas production of 4.0 l/day and 1.25 l/day, respectively.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2006.09a
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• pp.15-32
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• 2006

Biomass had been attracted public attention as eco-friendly resource which not increases the greenhouse gas like carbon dioxide. In this study, it had been collected pyrolytic products such as bio-oil, char and pyrolytic gas from various biomass in a fluidized bed reactor which is one of the fast pyrolysis processes. To understand the characteristics of biomass pyrolysis, the variation of products yield and chemical composition was determined with various operating parameters like temperature, gas velocity($U_{0}/U_{mf}$) and bed height(L/D). In the optimum operating conditions, gas yield and water content was the lowest and concentration of guaiacols and syringols were the highest. The maximum yields of bio-oil was from 55% to 58% at $400^{\circ}C$.