• Korean Journal of Environmental Agriculture
• /
• v.25 no.2
• /
• pp.118-123
• /
• 2006

To remove effectively order component ($NH_3\;and\;H_2S$) from pig house, biofilter was made of composted pine tree bark and polite and odor removal efficiency was evaluated in the lab and pilot scales. The columns were designed with ${\Phi}120mm{\times}450mm$ (H) and ${\Phi}850mm{\times}900mm$ (H) in the size in the lab and pilot scale testes, respectively. Single material of composted pine tree bark and polite and the mixture of two materials with 7:3 ratios (vol/vol) were packed in the column, and, herein air flow was controlled upward direction from column bottom. To enhance the efficiency of biofilter, ammonia (Rhodococcus equi A3) and hydrogen sulfide oxidizing bacteria (Alcaligenes sp. S5-5.2) were inoculated in packing materials before the test Removal effect of ammonia and hydrogen sulfide gases were higher in the mixture$[88.7{\sim}98.2%,\;89.5{\sim}97.9%]$ than that in single packing material (composted pine tree haft$[89.4{\sim}98.7%,\;78.7{\sim}85.6%]$ and petite$[65.3{\sim}73.2%,\;88.7{\sim}98.2%]$ by the lab scale biofilter. In the modeled pig house, about 96 and 91% of ammonia and hydrogen sulfide gases were removed by the pilot scale of biofilter, respectively. Conclusively, composted pine tree bark and polite could be a good candidate of biofilter packing materials to remove the odor components.

• Applied Chemistry for Engineering
• /
• v.17 no.3
• /
• pp.250-254
• /
• 2006

Reaction of $CO_2$ with $Li_{2}ZrO_{3}$ has been investigated in a TGA and the effects of $H_{2}$ and CO on the removal of $CO_{2}$ using $Li_{2}ZrO_{3}$ were evaluated in a packed bed reactor. The initial rate of $CO_{2}$ removal reaction of $Li_{2}ZrO_{3}$ increased with the increase of gas flow rate up to 100 mL/min and then was maintained, which implied the disappearance of the gas film resistance. The reaction of $CO_{2}$ with $Li_{2}ZrO_{3}$ took place as the first order and the range of optimum temperature was found to be about $500{\sim}600^{\circ}C$. XRD and SEM analysis showed the formation of crystalline $Li_{2}ZrO_{3}$ and porous $Li_{2}ZrO_{3}$/$ZrO_{2}$. The presence of $H_{2}$ did not affect the adsorption of $CO_2$ with $Li_2ZrO_3$. On the other hand, CO inhibited the sorption of $CO_{2}$ into $Li_{2}CO_{3}$(L) on $Li_{2}ZrO_{3}$.

• Korean Journal of Food Science and Technology
• /
• v.35 no.5
• /
• pp.797-802
• /
• 2003

Structured lipids (SL) were synthesized by esterification of corn oil and conjugated linoleic acid (CLA) in a continuous packed-bed column reactor. The effects of flow rate, reaction temperature, and substrate molar ratios were studied. The reaction was catalyzed by TL IM (immobilized lipase from Thermomyces lanuginosa). Results of triacylglycerol (TAG) analysis by GC showed that the incorporated CLA isomers were mainly cis9, trans11- and trans 10, cis12-CLA. Slower flow rates yielded higher incorporation, and maximum incorporation of CLA was obtained with a molar ratio of 1:3 (corn oil: CLA) at a temperature of $55^{\circ}C$. The obtained SLs had iodine values ranging from 120 to 128. The SLs were composed of TAG $(98{\sim}99%)$, 1,2- and 1,3-diacylglycerol ($0.7{\sim}1.3%$), and a small amount of monoacylglycerol.

• The Korean Journal of Zoology
• /
• v.31 no.1
• /
• pp.62-70
• /
• 1988

The distribution of respiratory chain complexes in beef heart and human muscle mitochondria has been explored by immunoeledron microscopy with antibodies made against beef heart mltochondriai proteins in conjundion with protein A cofloidai gold (l2nm particles). The antibodies used were made against NADH-conezyme Q reductase(complex I), ubiquinol-cytochrome-c-oxldoreductase (complex III) and cytochrome-c-oxidase(complex IV). Labeling of bed heart tissue with any of these antihodies gave gold particles randomly distributed along the mitochondrial inner membrane. The labeling of muscle tIssue mitochondria from a patient with a mitochondrial myopathy localized by biochemical analysis to complex III was quantitated and compared with the labeling of human control muscle tissue mitochondria. Four kinds of morphological changes in the mitochondrial fine strudure in the myopathy patient tissue have been found; paracrystalline inclusions consistIng of densely packed multi- lamellar structures, globular crystalline inclusions with high electron density, multilamellar strudure inclusion body(compadly and irregularly arranged concentric whirl shaped cristae)and golbular cyrstalilne inclusions located in the center of the whirl shaped cristae. Compex I and cytochrome-c-oxldase antihodies reacted to the same level in the mitochondria containing the crystalline inclusions and control mitochondria. Antibodies to complex III reacted very poorly to the mitochondria containing the crystalline Inclusions but strongly to control mitchondria. The globular crystalline inclusions in the mitochondria are not reacted antibodies to respiratory chain complexes.

• Journal of the Korean Wood Science and Technology
• /
• v.29 no.4
• /
• pp.40-47
• /
• 2001

To remove $Zn^{2+}$(422 ppm) and $Mn^{2+}$(53.1 ppm) from Sambo mine runoff(the total amount of heavy metals : 107 ppm) in Whasung, packed bed column tests were run in two stages plastic columns. The non-treated bark(Pinus densiflora, Quercus accutisima) of each 6 kg were placed into columns. The height and diameter of column were 60 cm and 45 cm, respectively. Flow rate ranged to 1 ${\ell}$/min for 15 days. The concentration of heavy metal ions in filtrate was determinded periodically. By the treatment of oak bark the initial concentration of $Zn^{2+}$ was maintained under 10 ppm(the adsorption rate: 64%) for 24 hr, while pine bark kept the initial concentration of $Zn^{2+}$ under 20 ppm(the adsorption rate: 53%) for 15 hr. However the initial concentration of $Mn^{2+}$ was reduced only to 10.6~18.6 ppm (the adsorption rate: 20~35%) until 10 hr. Thereafter, the adsorption of $Mn^{2+}$ by bark decreased rapidly. There was little difference in the adsorption ratio of $Mn^{2+}$ between oak and pine bark. The use of bark to remove $Zn^{2+}$ in Samba mine runoff was effective, but it wasn't proper to remove $Mn^{2+}$.

• Journal of the Korean Institute of Gas
• /
• v.20 no.4
• /
• pp.65-77
• /
• 2016

Modeling for complex reacting flow in Fischer-Tropsch reactor is one of the challenges in the field of Computational Fluid Dynamics (CFD). It is hard to derive each and every reaction rate for all chemical species because Fisher-Tropsch reaction produces many kinds of hydrocarbons which include lots of isomers. To overcome this problem, after analyzing the existing methodologies for reaction rate modeling, non-Anderson-Schulz-Flory methodology is selected to model the detailed reaction rates. In addition, the inside flow has feature of multi-phase flow, and the methodologies for modeling multi-phase flow depend on the interference between the phases, distribution of the dispersed phase, flow pattern, etc. However, existing studies have used a variety of inside flow modeling methodologies with no basis or rationale for the feasibility. Modeling inside flow based on the experimental observation of the flow would be the best way, however, with limited resources we infer the probable regime of inside flow based on conventional fluid dynamics theory; select the appropriate methodology of Mixture model; and perform systematic CFD modeling. The model presented in this study is validated through comparisons between experimental data and simulation results for 10 experimental conditions.

• Korean Chemical Engineering Research
• /
• v.46 no.5
• /
• pp.931-937
• /
• 2008

Rigorous multiscale modelling and simulation of the MTR for WGSR was carried out to accurately predict the behavior of process variables and the reactor performance. The MTR consists of 4 fixed bed tube reactors packed with heterogeneous catalysts, as well as surrounding shell part for the cooling purpose. Considering that fluid flow field and reaction kinetics give a great influence on the reactor performance, employing multiscale methodology encompassing Computational Fluid Dynamics (CFD) and process modeling was natural and, in a sense, inevitable conclusion. Inlet and outlet temperature of the reactant fluid at the tube side was $345^{\circ}C$ and $390^{\circ}C$, respectively and the CO conversion at the exit of the tube side with these conditions approached to about 0.89. At the shell side, the inlet and outlet temperature of the cooling fluid, which flows counter-currently to tube flow, was $190^{\circ}C$ and $240^{\circ}C$. From this heat exchange, the energy saving was achieved for the flow at shell side and temperature of the tube side was properly controlled to obtain high CO conversion. The simulation results from this research were accurately comparable to the experimental data from various papers.

• Journal of Korean Society of Environmental Engineers
• /
• v.22 no.1
• /
• pp.169-178
• /
• 2000

Perovskite oxide catalysts doped on porous alumina beads are prepared in a citric acid solution. To investigate the applicability of the catalysts to the hot gas cleanup, a series of experiments on the reduction characteristics of $NO_x$ by CO as a reducing agent are carried out in a packed bed reactor containing the catalysts. Parameters tested are the operating temperature and $CO/NO_x$ molar ratio. It is found that mixed complex oxides of $La_{0.5}Sr_{0.5}CoO_3$, $SrAl_{12}O_{19}$ and $LaAl_{11}O_{18}$ are uniformly distributed on the alumina beads. The conversion efficiency of $NO_x$ by CO sharply increases with the operating temperature up to $700^{\circ}C$ and then approaches 100% when $CO/NO_x$ molar ratio is greater than 1.0. The conversion efficiency of $NO_x$ is maintained by over 98% during a continuous operation for 23 hours at $800^{\circ}C$ and space velocity of $10700hr^{-1}$.

• Journal of the Korea Organic Resources Recycling Association
• /
• v.19 no.2
• /
• pp.55-69
• /
• 2011

Use of disposer at the kitchens of Korean apartments is inevitable in treating their foodwaste having a water content of more than 80%. Also we have to ensure that this extra disposer-foodwaste BOD loadings be treated properly by installing/operating a pre-treatment system before this wastewater enters public sewer system. However, the degree of BOD removal should not be excessive since a BOD/N ratio higher than 5 is required for removing N/P at a municipal wastewater treatment plant. The removal of BOD/N in the pretreatment system rather than BOD alone can be an alternative solution in solving this problem. The particles separated by sedimentation, screen or packed-bed can be anaerobically digested at apartment sites to generate biogas that can be used for simple digester heating and to generate volatile fatty acids (VFAs) for nitrogen removal. We suggest that Korean government grants a temporary license (say for 5 years) to foodwaste treatment companies in collaboration with apartment construction companies which may do business and develop various kinds of disposer-foodwaste treatment systems in diverse wastewater discharge systems of Korean apartments.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.26 no.6B
• /
• pp.689-694
• /
• 2006

The system performance of a bioactive foam reactor (BFR), that consists of a foam column using a surfactant and a biodegradation basin containing suspended bacteria, was investigated for the treatment of gaseous toluene or a mixture of four volatile organic compounds (VOCs, benzene, toluene, p-xylene, and styrene). Overall, the BFR achieved stable VOC removal efficiencies, indicating that it can be used as a potential alternative over conventional packed-bed biofilters. Furthermore, a dynamic loading test showed that relatively constant removal was maintained at the elevated loading due to a high mass transfer rate in the foam column. However, as the inlet concentration of VOCs increased, a portion of the VOCs mass-transferred to the liquid phase was stripped out from the biodegradation basin, resulting in a decrease in the overall removal efficiency. In the BFR, the removal efficiency of the individual VOC was mainly determined depending on the biodegradation rate (styrene > toluene > benzene > p-xylene), rather than the mass transfer rate. Consequently, increases in the microbial activity and the volume of the basin could improve the overall performance of the BFR system. Further investigation on microbial activity and community dynamics is required for the BFR when subjected to high loadings of VOC mixtures.