• Biotechnology and Bioprocess Engineering:BBE
• /
• v.7 no.6
• /
• pp.371-374
• /
• 2002

Production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)［P(3HB/V)］, by fed-batch culture of recombinant Escherichia coli harboring a plasmid containing the Alcaligenes latus polyhy-droxyalkanoate (PHA) biosynthesis genes, was examined in two pilot-scale fermentors with air supply only, In a 30 L fermentor having a XLa value of 0.11 S­$^1$, the final P(3HB/V) concentration and the P(3HB/V) content obtained were 29.6 g/L and 70.1 wt%, respectively giving a productivity of 1.37 g P(3HB/V)/L-h. In a 300 L fermentor having a XLa of 0.03 S­$^1$, the P(3HB/V) concentration and the P(3HB/V) content were 20.4 g/L and 69 wt%, respectively giving a productivity of 1.06g P(3HB/V)/L-h. These results suggest that economical production of P(3HB/V) is possible by fed-batch culture of recombinant E. coli in a large-scale fermentor having low KLa value.

• Anxiety and mood
• /
• v.5 no.2
• /
• pp.120-124
• /
• 2009

Objectives : This pilot study examined the physical and psychological sequela of Korean War victims. Methods : Of 255 elderly who completed the Mini International Neuropsychiatric Interview (MINI), we selected 16 subjects who suffered severe traumatic experiences during the Korean War and met more than 2 specified symptoms of PTSD in DSM-IV-TR and 16 controls. Demographic characteristics, medical history including hypertension, diabetes mellitus, hypercholesterolemia and brain infarction, Geriatric Depression Scale, State-Trait Anxiety Inventory, suicide scale in MINI, and a scale for the assessment of somatic symptoms were compared between subjects with trauma experience and controls. Results : Subjects with trauma experience were more likely to have brain infarction and diabetes mellitus compared to control group. Depressive symptoms and suicidal risk were significantly higher in subjects with trauma experience than controls. Subjects with trauma experience showed significantly higher scores in Trait Anxiety scale and more complained of pain than controls. Conclusion : This study suggests that traumatic experience probably induce physical and psychological problem even 60 years later. Further studies are needed to confirm the results of this pilot study.

• Journal of Microbiology and Biotechnology
• /
• v.20 no.4
• /
• pp.763-766
• /
• 2010

An efficient and simple fermentation process was developed for the production of ${\gamma}$-aminobutyric acid (GABA) by Lactobacillus sakei B2-16. When the L. sakei B2-16 was cultivated in the rice bran extracts medium containing 4% sucrose, 1% yeast extract, and 12% monosodium glutamate, the maximum GABA concentration reached 660.0 mM with 100% conversion yield, showing the 2.4- fold higher GABA concentration compared with the modified MRS medium without the rice bran extracts. The GABA production was scaled-up from a laboratory scale (5 l) to a pilot (300 l) and a plant (5,000 l) scale to investigate the application possibility of GABA production to industrial fields. The production yields at the pilot and plant scales were similar to the laboratory scale using rice bran extracts medium, which could be effective for the low-cost production of GABA.

• Environmental Engineering Research
• /
• v.14 no.3
• /
• pp.195-199
• /
• 2009

A series of laboratory-scale corrosion experiments was carried out to observe the effect of dissolved oxygen (DO) in the presence of other water quality parameters, such as hardness, Cl-, and pH using various pipe materials. In addition, a simulated loop system was installed at a water treatment plant for pilot-scale experiment. Laboratory-scale experiment showed that corrosion rates for galvanized steel pipe (GSP), carbon steel pipe (CSP), and ductile cast iron pipe (DCIP) were decreased to 72%, 75%, and 91% by reducing DO concentration from 9${\pm}$0.5 mg/L to 2${\pm}$0.5 mg/L. From the pilot scale experiment, it was further identified that the average ionization rate of zinc in GSP decreased from 0.00533 to 0.00078 mg/$cm^2$/d by controlling the concentration of DO. The reduction of average ionization rate for copper pipe (CP) and stainless steel pipe (SSP) were 71.4% for Cu and 63.5% for Fe, respectively. From this study, it was concluded that DO could be used as a major parameter in controlling the corrosion of water pipes.

• Journal of Korean Society of Water and Wastewater
• /
• v.22 no.4
• /
• pp.445-448
• /
• 2008

The application of the membrane filtration process has been increased for the drinking water treatment system because of excellent quality of treated water compared with the sand filtration process. The selection of suitable pre-treatment processes and optimum flux according to the characteristics of raw water are important factors for the design of membrane processes. In this study, the most efficient pre-treatment processes for drinking water was selected by investigating the effects of pre-treatment processes on the operational stability of the membrane filtration process. Both lab-scale and pilot-scale experiments were conducted. In the lab-scale test, the effect of pre-treatment processes on the stability of the membrane filtration process was investigated indirectly by comparing the performance of membrane flux for raw water, pre-treated water, and membrane permeated water. In the pilot-scale test, the usefulness of prefiltration processes was assessed by comparing the performance of single membrane process and hybrid coagulation-membrane process. The results indicated that the coagulation process contributed to the stabilization of trans-membrane pressure (TMP) by removing contaminants on membranes, though the pre-filtration process had little effect on the TMP.

• Journal of Biosystems Engineering
• /
• v.37 no.6
• /
• pp.365-372
• /
• 2012

Purpose: Performance of slurry composting and biofiltration with methane production (SCB-M) using swine manure and sawdust was evaluated. The suitable specific liquid input (SLI) was determined at lab-scale SCB. Method: In lab-scale SCB, the SLI test was performed at liquid input rate of 0.04, 0.09, $0.17cc/cm^3$ with constant sawdust volume. In pilot-scale SCB-M, the swine manure was fed to methane digester at organic loading rate (OLR) of 0.25-0.5 g VS/L/d. The effluent from methane digester was filtered using SCB. Results: The SLI at $0.04cc/cm^3$ showed good performance in terms of retention time. In pilot-scale SCB, the removal of $NH_3$-N and total nitrogen (T-N) was found to be around 59% and 28%, respectively. Similarly, volatile fatty acid (VFA) and total chemical oxygen demand (TCOD) removal was found be 56% and 43%, respectively. Conclusions: For SCB-M process, the SLI of $0.04cc/cm^3$ is recommended. The performance of swine manure treatment was improved more by using SCB-M system than using methane digester only.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2004.04a
• /
• pp.205-208
• /
• 2004

Tile pilot scale biopile system was designed and constructed for evaluation of biopile efficiency. For the biopile system construction, two soil samples that were contaminated by mainly diesel were selected. The pilot scale biopile were consisted of the biopile dome, aeration system and monitoring system and two biopiles(pile A and pile B) were operated with nutrients and inoculum for more 100 days. The initial TPH concentrations for pile A and pile B were about 10,000 mg/kg and 2,300 mg/kg, respectively. After 70 days, the microbial densities in the pile A was increased and in the pile B it was no changed. The TPH contents decreased about 70% in the pile A and 30% in the pile B. Also, various kinds of PAHs were detected by analyzing the GC/MSD, and the reducing ratio in the piles A and pile B were similarly declined. The average biodegradation rates were calculated about 66.8mg/kg-day in the pile A and 10.9mg/kg-day in the pile B. During the operation period, pile temperature was the major limiting condition for the efficiency of all biopiles.

• Journal of the Korean Society of Combustion
• /
• v.16 no.3
• /
• pp.12-20
• /
• 2011

Oxy-coal combustion for $CO_2$ capture in coal power plants entails a mode switching from air-firing to oxyfiring. In this study, procedure of the mode switching was investigated and discussed through experiments in pilot scale facilities: (1) a 0.3 $MW_{th}$ furnace with a vertical single burner and a FGR(Flue Gas Recirculation) system (2) a 1 $MW_{th}$ furnace with horizontal 4 burners and a FGR system. Principle of the mode switching was established and performed with control of FD fan, FGR fan, ID fan and oxygen flow rates. We have found that equivalence ratio in the oxy-firing mode should be increased more than that in the air-firing to achieve stable mode switching. Control of FD, ID and FGR fans should be performed carefully in the mode switching, in the sense of complete combustion and flame attachment. Moisture contents in the ash and the flue gas recycled to the primary oxidizer stream should be removed to prevent condensation, corrosion and duct clogging.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2007.09a
• /
• pp.558-569
• /
• 2007

It is important to obtain real-time data from long-term monitoring of landfills and develop leachate leakage detection system for the integrated management of landfills. A novel real time monitoring system and early leakage detection system was suggested in this study. The suggested monitoring system is composed of two parts; (1) a set of moisture sensors which monitor the areas surrounding the landfill, and (2) a set of moisture and temperature sensors which monitor the landfill inside. For the assessment for landfills stabilization, real-time monitoring system was evaluated in dry and wet cell of pilot-site. In addition, the grid-net electrical conductivity measurement system was also suggested as early leakage detection system. In this study, the field applicability of suggested systems was evaluated through pilot-scale field tests. The results of pilot-scale field model tests indicate that the grid-net electrical conductivity measurement method can be applicable to the detection of landfill leachate at the initial stage of intrusion, and thus has a potential for monitoring leachate leakage at waste landfills.

• 한국신재생에너지학회:학술대회논문집
• /
• 2011.11a
• /
• pp.175.1-175.1
• /
• 2011

A rotating activated bacillus contactor (RABC) process with a series of aerobic reactors was tested in pilot scale to treat digested liquid from an anaerobic digester treating swine wastewater and sewage sludge. The influent (digested liquid) for the RABC process showed C/N ratios less than 2 as a typical feature of effluent from anaerobic digesters. The pilot process, which consists of three 3 RABC reactors, four aerobic tanks and a sedimentation tank, was operated for 210 days with a hydraulic retention time of 20 days without pH and temperature control. Since the Bacillus-enriched aerobic reactors shows high efficiencies of nitrogen removal at low DO levels less than 1.0 mg/L, they were operated at reduced aeration intensities. With relatively low concentrations of organics in comparison with nitrogen concentrations, the RABC process tested in this study showed stable and high nitrogen and organics removal efficiencies over 80%. The nitrogen removal process tested in this study was proven to be an effective and operation-cost saving (lower aeration) method to remove nitrogen without adding external carbon sources to meet the optimum C/N ratio.