• KSBB Journal
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• v.16 no.3
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• pp.281-285
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• 2001

Biofiltration of volatile organic compounds (VOCs) was performed for 80 days in a biofilter packed with peat. The empty bed residence time was 3.2 min. for a gas mixture of isoprene, dimethyl sulfide, chloroform. benzene, trichlorethylene, toluene, m0xylene, o-xylene and styrene. After 34 days of acclimatization the removal efficiency for a 83 g/㎥ gas input was 93% at $25^{circ}C$ and 73% at $45^{circ}C$, respectively. The maximum cell density at $25^{circ}C$ was 1.12$\times$10(sup)8 cells/g. Removal efficiencies of m-xylene and toluene (91%) were better than that of benzene (86%). The first quarter of the packed column removed 60% of the incoming VOCs.

• KSBB Journal
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• v.18 no.6
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• pp.500-505
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• 2003

‘LK (lipoprotein kringle) 68’is a polypeptide of a modified ansiostatin consisting of three kringle structures that might be clinically useful as a potential cancer therapeutics. It can be produced by overexpressing it as inclusion body in recombinant E. coli. In this study, solid-phase refolding processes using packed bed adsorption (PBA) and expanded bed adsorption (EBA) column were carried out to compare their refolding yields with that of the conventional, solution-phase refolding process, For the solution-phase and the PBA-mediated processes employing Q-Sepharose, washed inclusion body was used as the starting material, whereas both washed inclusion body and E. coli homogenate were used for the EBA-mediated process employing streamline DEAE. On the final recovery LK68 per unit mass of wet cell basis, the EBA- and PBA-mediated processes showed about 2.7- and 1.5-fold higher yields, respectively, than the solution-phase refolding method. The solid-phase refolded LK68 demonstrated the same Iysine binding bioactivity and the retention time in the RP-and SEC-HPLC as those of the native protein.

• Korean Journal of Environmental Agriculture
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• v.15 no.2
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• pp.232-238
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• 1996

This study was conducted to find out the optimum condition for $NH_4-N$ removal from wastewater by a zeolite column. The removal efficiency of $NH_4-N$ by a glass column packed with decreased with the increase in initial concentration, percolation velocity and fraction number. The result of multiple stepwise regressions, $NH_4-N$ removal efficiency by the zeolite column showed a high correlationship with various parameters such as percolation velocity, initial concentration, adsorption amount and fraction number. Theoretical formula by parameter coefficients of multiple stepwise regression was found to be $NH_4-N$ removal $efficiency=0.620{\times}amount$ of zeolite $-0.456{\times}percolation$ velocity $-0.212{\times}initial$ concentration $-3.038{\times}fraction$ number+100.1 In the case of the $NH_4-N$ removal efficiency in cattle farming wastewater, the experimental data were nearly coincident with the theoretical formula.

• Journal of Soil and Groundwater Environment
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• v.23 no.1
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• pp.54-62
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• 2018

This paper is aimed at source tracking of soil heavy metal contamination at a site established by reusing construction wastes. The soil heavy metal concentration at the study site peaked at a depth range of 5-10 m. Column studies were conducted to investigate the possibility of the contamination scenario of infiltration of stormwater carrying heavy metals of ground origin followed by selective heavy metal accumulation at the 5-10 m depth range. Almost all amount of lead, zinc, cadmium, and nickel introduced to the columns each packed with 0-5 m or 5-10 m field soil were accumulated in the column. The very poor heavy metal mobility in spite of the weak association of the heavy metals with the soil (characterized by a sequential extraction procedure) can be attributed to the high pH (10-11) of the construction wastes. From the results, the heavy metal contamination of the subsurface soil by an external heavy metal source was determined to be very unlikely at the study site. The column study applied in the current study is expected to be a useful methodology to present direct evidence of the contaminant source tracking at soil contamination sites.

• Journal of Korean Society of Environmental Engineers
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• v.30 no.10
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• pp.984-991
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• 2008

This paper reports experimental results, demonstrating the feasibility of horseradish peroxidase(HRP) and H$_2$O$_2$ to reduce phenol transport in saturated porous media. A laboratory-scale packed column reactor(ID: 4.1 cm, sand-bed height 12 cm) column was utilized to simulate injection of HRP and H$_2$O$_2$ into an aquifer contaminated with phenol. Effluent concentrations of phenol and polymerization products were monitored before and after enzyme addition under various experimental conditions(enzyme dose: 0$\sim$2 AU/mL, [ionic strength]: 5$\sim$100 mM, pH: 5$\sim$9). The concentration of phenol in the column effluent was found to decrease by nearly 90% in the presence of HRP(2 AU/mL) and H$_2$O$_2$ in the continuous flow system at pH 7 and ionic strength 20 mM. The influent phenol was converted in the system to insoluble precipitate, which deposited in pore spaces. The remains were discharged as soluble oligomers. About 8% of total pore volume in column system was decreased by deposition of polymer produced.

• Journal of Wetlands Research
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• v.18 no.1
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• pp.68-75
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• 2016

A set of lab-scale polymer synthetic fiber packed column wetlands composing three columns (CW1, CW2 and CW3) with different hydraulic regimes, recirculation frequencies and pollutant loading rates, were operated in 2012. Synthetic fiber tested as an alternative wetland medium for soil mixture or gravel which has been widely used, has very high pore size and volume, so that clogging opportunity can be greatly avoided. The inflow to the wetland was artificial stormwater. All the wetlands achieved effective removal of TSS (94%~96%), TCOD (68%~73%), TN (35%~58%), TKN (62%~73%) and NH4-N (85%~ 99%). Particularly, it was observed that COD was released from the fiber during one distinct period in all wetlands. This was probably due to the degradation of polymer fiber, and the released organic matters were found to serve as carbon source for denitrification. In addition, with longer retention time and frequent recirculation, lower effluent concentration was observed. With higher pollutant loading rate, higher nitrification and denitrification rates were achieved. However, although organic matters were released from the fiber, the lack of carbon source was still the limiting factor for the system since the release persisted only for 40 days.

• Journal of Korea Soil Environment Society
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• v.2 no.2
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• pp.25-33
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• 1997

To investigate the effects of cow manure compost(CMC) on soil and water environment as non-point source, the elution patterns of anions were determined in muti-layered soil columns which were consisted of one top and one bottom in combination. The top soil columns were uniformly packed with Ap horizon soils amended with air-dried CMC at different ratios(0, 2, 4, 6%, wt/wt), the bottom ones were packed with of B horizon soils of 15, 30, and 45cm in length. After saturating the each soil column, the leachate were collected from the bottom of the column while the double-ionized water was applied from the surface of the column by constant head method. From the hydraulic conductivity and anion eluted were measured in the leachate. Each saturated hydraulic conductivities for top and the bottom soils were 3$\times$$10^{-4}$sec and 1.6$\times$$10^{-3}$cm/sec. Most of water soluble chloride and sulfate, having non-specific adsorption characteristics onto the soil particles, were eluted within 1 PV, showing that there was no apparent retardation of anion movement with increasing CMC contents in the top soils. The effect of soil depths on anion movement were similar to the results of CMC contents. Sulfate of having both of non-specific and specific adsorption characteristics was also recovered in the effluent within 1 PV, while the elution curves were slightly skewed to the right showing that the CMC affected the movement of sulfate. Phosphate of specific adsorption characteristics was hardly eluted within 5 PV.

• KSBB Journal
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• v.10 no.3
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• pp.283-291
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• 1995

The characteristics of aminopeptidase M(ApM) immobilized covalently on Cellufine Formyl and the continuous production of authentic human growth hormone(hGH) from methionyl human growth hormono(met-hGH) using the column reactor packed with immobilized ApM were investigated. Immobilized ApM with the proportion of 2.3mg ApM per 1g Cellufine Formyl gel had the highest met-hGH conversion activity. The optimum pH(7.0) and temperature($55^{\circ}C$) showed no appreciable difference between free and immobilized enzymes and the optimum temperature in continuous operation of the column reactor was also found to be $55^{\circ}C$. Under the conditions at which met-hGH was converted completely to hGH, the yield and productivity were about 77% and 0.8mg hGH/ml$.$h, respectively. In two column reactors of different sizes, met-hGH was converted to hGH with the same conversion rates and hGH yields at the same space velocities. The half-life of the reactor systems at $45^{\circ}C$ and $55^{\circ}C$ were projected from the continuous operations for 90 days to be 225 days and 81 days, respectively.

• Journal of Korean Society on Water Environment
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• v.20 no.2
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• pp.104-109
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• 2004

Removal of nutrients from domestic sewage or industrial wastewater is needed to protect surface waters from eutrophication. This research was carried out to remove the nitrogen (N) and phosphorus (P) from the wastewater using the iron oxide obtained from the steel industry and the natural zeolite, respectively. This research was conducted in both batch and continuous systems. The removal efficiency of the nutrients was evaluated in the batch system using the varying concentrations of zeolite and iron oxide added. The removal efficiency of N was 60% at the 8g of zeolite added. In the same condition, the removal efficiencies of N were 76% and 82% at 12g and 16g of zeolite added, respectively. Removal efficiency of P was 80% as 8g of iron oxide was added. The removal efficiency of P was correspondingly increased as the concentration of iron oxide was increased. Continuous column system was also used to evaluate the removal efficiency of N and P by the addition of zeolite and ferric oxide, respectively. Removal efficiencies of N were compared in the mixed packing, two stage, and four stage columns, respectively. The removal efficiencies (80%) of N in the separate packed columns (two and four stages) were higher than the mixed packing column (400%) after 90 hr. Whereas, the removal efficiencies of P were similar to each other in the three columns.

• Journal of Environmental Health Sciences
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• v.21 no.2
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• pp.12-19
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• 1995

The objectives of this research prograln were to study the ozonation characteristics of phenol contaminated wastewater in the continuous packed column reactor (PCR) and the bubble column reactor (BCR) using ozone that has a strong oxidizing potential, and to provide the fundamentals of ozonizing the phenol contaminated wastewater. Among various influencing factors on phenol decomposition through the oxidation by ozone, phenol/ozone mde ratio was chosen as reaction parameters. Concerning the phenol/ozone mde ratio, as the influent phenol concentration increased from 30 mg/l to 150 mg/l, the phenol removal efficiency decreased from 99% for 30 mg/l to 83.7% for 150 mg/l, in PCR. PCR also showed higher treatment efficiency than BCR by 1% for 30 mg/l and 2.2% for 150 mg/l, respectively. The ozone utilization efficiency of PCR for the phenol concentration 30 mg/l was higher than that of BCR while the efficiency of both reactors was 99.9% for the phenol concentration of 150 mg/l.