• Title/Summary/Keyword: fill and draw

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Comparison of Bio-ethanol Productivity Using Food Wastes by Various Culture Modes (에탄올 발효방법에 따른 음식물류 폐기물의 바이오에탄올 생산성 비교)

  • Kang, Hee-Jeong;Li, Hong-Xian;Kim, Yong-Jin;Kim, Seong-Jun
    • KSBB Journal
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    • v.25 no.5
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    • pp.471-477
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    • 2010
  • In order to improve bio-ethanol productivity by various cultivation methods in this paper, the culture modes using food wastes, such as batch culture, high-cell-density fermentation, SSF (simultaneous saccharification and fermentation) by fill & draw, continuous culture by fill & draw were performed and their productivities were compared. SSFs by fill & draw were performed by continuous decompression using 1 L evaporator system, and by 10 L bioreactor without decompression. In addition, the continuous cultures by fill & draw mode using SFW (saccharafied food wastes) medium were performed by changes of 40% culture broth with intervals of 12 h (0.03 $h^{-1}$), 6 h (0.07 $h^{-1}$), 3 h (0.13 $h^{-1}$). Consequently, productivities of bio-ethanol were 2.52 g/L-h and 1.30 g/L-h in batch culture and high- cell-density fermentation, respectively. The productivities of SSF by fill & draw showed 2.24 g/L-h and 2.03 g/L-h in continuous decompression with 1 L evaporator and 10 L bioreactor without decompression, respectively. Also, the productivities in continuous culture by fill & draw modes showed 2.02 g/L-h, 4.07 g/L-h and 6.25 g/L-h by medium change with intervals of 12 h, 6 h, and 3 h, respectively. In conclusion, the highest ethanol productivity was obtained in the continuous culture mode by fill & draw with dilution rate of 0.13 $h^{-1}$.

Comparison of cellulolytic enzyme productivities in various semicontinuous culture modes of Trichoderma inhamatum KSJ1 (Trichoderma inhamatum KSJ1의 반연속배양 방식에 따른 섬유소분해효소의 생산성 비교)

  • Li, Hong-Xian;Kim, Seong-Jun
    • KSBB Journal
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    • v.24 no.1
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    • pp.70-74
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    • 2009
  • For continuous culture of cellulolytic enzymes production to saccharify food wastes, refill concentration of Mandel's medium for continuous culture was 0.5%, and refill intervals were determined to 12 hours by analysis of COD and total nitrogen concentration after 4-days batch culture in flask level. As a result, amylase and FPase productivities were 3.5 and 1.0 U/L.hr, respectively. In 10 L bioreactor, the batch culture mode was compared with fed-batch, fill-and-draw for continuous production of cellulolytic enzyme. Enzyme productivities were most high at batch culture and followed by fed-batch culture. Amylase and FPase activities were 42.3 and 5.6 U/L.hr at batch culture, and 23.0, 2.8 U/L.hr at fed-batch culture, respectively. As a result, in continuous cultivation of cellulolytic enzymes by T. inhamatum KSJ1, the mode of fed-batch was most effective in 10 L bioreactor.

Nitrification and Denitrification by Using a Sequencing Batch Reactor System (Sequencing Batch Reactor (SBR)를 이용한 질산화와 탈질산화)

  • PARK Jong-Ho;LEE Won-Ho;CHO Kyu-Seok;HWANG Gyu-Deok
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.36 no.3
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    • pp.247-253
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    • 2003
  • Sequencing Batch Reactor (SBR) was operated under various experimental conditions to improve the efficiency of biological filters used for the treatment of recycled wastewater from aquaculture. This SBR system was operated for removing COD, ammonia and suspended solid that were the major pollutants in aquaculture wastewater. Aerobic and anoxic conditions after FILL mode were applied intermittently for effective removal of nitrogen. SETTLE and DRAW modes were followed by the complete aerobic and anoxic REACT mode. The total volume of the SBR was 75 liter, while the working volume in a cycle was 35 liters. When the final operating strategy of the SBR was FILL/REACT/SETTLE/DRAW of 0.5/10/1/0.5 hr. the removal efficiencies of TCODcr, $NH_{4}^{+}-N,$ and T-N were 94, 98, and $89\%,$ respectively.

Electronic Ballast with Modified Valley fill and Charge Pump Capacitor for Prolonged Filaments Preheating and Power Factor Correction (변형된 벨리필 구조와 전하펌프 커패시터가 결합되어 필라멘트 예열기능과 역률개선능력을 가진 형광등용 전자식 안정기)

  • Chae, Gyun;Ryoo, Tae-Ha;Cho, Gyu-Hyeong
    • Proceedings of the KIEE Conference
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    • 1999.07f
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    • pp.2798-2800
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    • 1999
  • A new circuit, modified valley fill (MVF) combined with resonant inductor of the self-excited resonant inverter and charge pump capacitors(CPCs), is presented to achieve high PF electronic ballast providing sufficient preheat current to lamp filaments for soft start maintaining low DC bus voltage. The MVF can adjust the valley voltage higher than half the peak line voltage. The CPCs draw the current from the input line to make up the current waveform during the valley interval. The measured PF and THD are 0.99 and 12%, respectively. The lamp current CF is also acceptable in the proposed circuit. The proposed circuit is suitable for implementing cost-effective electronic ballast.

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A Study of Air Dispersion Modeling in Highway Environmental Impact Assessment (고속도로 환경영향평가를 위한 대기확산모델링 연구)

  • Koo, Youn-Seo;Ha, Yong-Sun;Kim, A-Leum;Jeon, Eui-Chan;Lee, Seong-Ho;Kim, Sung-Tae;Kang, Hye-Jin
    • Journal of Environmental Impact Assessment
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    • v.14 no.6
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    • pp.427-441
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    • 2005
  • In order to choose proper dispersion model and emission factors suitable in Korea in evaluating the effect of pollutants emitted by the vehicles in highway on nearby area, various road dispersion models and vehicle emission factors were reviewed. With theoretical inter-comparisons of the exiting models for line source, CALINE 3 and CALINE 4 models which were suggested by US EPA were selected as the road dispersion models for further evaluation with the measurement. The emission factors suggested by Korean Ministry of Environment was turned out to be appropriate since the classification of vehicle kinds was simple and easy to apply in Korea. The comparisons of predicted concentrations by CALINE 3 and 4 models with the measurements in flat, fill and bridge road types showed that CO and PM-10 were in good agreements with experiments and the differences between CALINE 3 and 4 models are negligible. The model concentrations of $NO_2$ by CALINE 4 were also in good agreement with the measurement but those by CALINE 3 were over-predicted. The discrepancies in CALINE 3 model were due to rapid decay reaction of $NO_2$ near the highway, which was not included in CALINE 3 model. For the road type with one & two side cutting grounds, the similar patterns as the flat & fill road type for CO, PM10, & $NO_2$ were observed but the number of data for comparison in these cases were not enough to draw the conclusion. These results lead to the conclusion that CALINE4 model is proper in road environmental impact assessment near the highway in flat, fill and bridge road types.

Psychometrics of Perspective Taking in Writing: CombiningManualCoding and Computational Approaches

  • Minkyung Cho
    • International journal of advanced smart convergence
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    • v.12 no.1
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    • pp.120-129
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    • 2023
  • Perspective taking, one's knowledge of their own mental and emotional states and inferences about others' mental and emotional states, is an important higher order cognitive skill required in successful writing. However, there has not been much research on the identification and examiantion of the psychometrics of perspective taking. To fill in this gap, I reviewed the psychological and cognitive frameworks of perspective taking including theory of mind, audience awareness, development of epistemological understanding, and argumentation schema. I also reviewed various methods of examining the psychometric properties of perspective taking in written composition, including both manual and computational approaches. The review of literature yielded suggestions on the development of manual coding scheme for perspective taking as well as the selection of indexes to draw from natural language processing tools. Challenges and affordances of combining the manual and computational approach are discussed along with future research directions to advance the field of psycholinguistics.

Aeration Control of Thermophilic Aerobic Digestion Using Fluorescence Monitoring

  • Kim, Young-Kee;Oh, Byung-Keun
    • Journal of Microbiology and Biotechnology
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    • v.19 no.1
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    • pp.93-98
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    • 2009
  • The thermophilic aerobic digestion (TAD) process is recognized as an effective method for rapid waste activated sludge (WAS) degradation and the deactivation of pathogenic microorganisms. Yet, high energy costs due to heating and aeration have limited the commercialization of economical TAD processes. Previous research on autothermal thermophilic aerobic digestion (ATAD) has already reduced the heating cost. However, only a few studies have focused on reducing the aeration cost. Therefore, this study applied a two-step aeration control strategy to a fill-and-draw mode semicontinuous TAD process. The NADH-dependent fluorescence was monitored throughout the TAD experiment, and the aeration rate shifted according to the fluorescence intensity. As a result, the simple two-step aeration control operation achieved a 20.3% reduction in the total aeration, while maintaining an effective and stable operation. It is also expected that more savings can be achieved with a further reduction of the lower aeration rate or multisegmentation of the aeration rate.

A Study on the Maintenance Factors of Multi-family Housing through a Comparison of the Awareness of Managers and Resident (관리자와 거주자의 인식 비교를 통한 공동주택 유지관리 항목 도출에 관한 연구)

  • Jung, Jung-Hee;Kim, Ju-Hyung;Seo, Hee-Chang;Kim, Jae-Jun
    • Journal of the Korean housing association
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    • v.24 no.4
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    • pp.19-27
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    • 2013
  • Professional management of multi-family housing to maintain physical environments was essential to cope with timeworn housings as the residents share various facilities and spaces therein altogether. Therefore, this research intended to collect the key aspects and items for efficient management of multi-family housing and such data and information was obtained partly by way of conducting survey of the residents therein. This research conducted survey 3 times questionnaire with the residents (n=30) living in multi-family housings and managers (n=30) of multi-family housings. 3 times surveys that consisted of 1 open end and 2 closed end was conducted to draw objectified results and experimental analysis was made at each stage to achieve the purpose of this study. And survey period to fill in a questionnaire was Aug. 17. 2012-Sep. 05. 2012. This research revealed that maintaining safety and healthy and high quality living environment is critical in the management of multi-family housing. Accordingly, proper management manual prepared complying with the requirements of the residents in the multi-family housing management.

관리형 매립시설 침출수 중 $SCN^-$제거를 위한 SBR 공정

  • Seong, Se-Hyeon;Hwang, Seok-Hwan
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.274-277
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    • 2001
  • This research was conducted as a part of continuous development of a bioprocess to treat thiocyanate($SCN^-$) in the leachate from an industrial landfill site. Detailed characteristics of the leachate, physical and chemical, was analyzed in this study. Time to reach equilibrium in $SCN^-$ degradation at different temperature, similar to the annual variation. was investigated for posssible adaptation of the bioprocess in the treatment site. Complete mineralization of $SCN^-$ to ammonia. bicarbonate and sulfate at all temperature range with except $5^{\circ}C$ trial was observed with different time elapsed to reach equilibrium. which shortened as the process of Fill-Draw proceeded. The final metabolites were mainly nitrate and sulfate. No fouling odor was detected and the settling characteristic of the biomass after the treatment was good(i.e., sludge volume index(SVI) ${\le}$80). Using MWT sludge as an inoculum showed better performance with respect to the elapsed time for treatment and sedimentation characteristics than those of using 2BET sludge.

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Application of a Thermophilic Aerobic Digestion Process to Industrial Waste Activated Sludge Treatment

  • Kim, Young-Kee;Eom, Yong-Suk;Oh, Byung-Keun;Lee, Won-Hong;Choi, Jeong-Woo
    • Journal of Microbiology and Biotechnology
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    • v.11 no.4
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    • pp.570-576
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    • 2001
  • Thermophilic aerobic bacteria were applied in the degradation of industrial waste activated sludge (WAS) on a laboratory scale expreiment. The performance of digestion was estimated by measuring the reduction of total suspended solids (TSS), dissolved organic carbon (DOC), and total organic carbon (TOC). Among three strains of Bacillus stearothermophilus and three strains of Thermus species, B. stearothemophilus ATCC 31197 showed the best overall efficiency level for the degradation of industrial WAS, which was collected from a wastewater treatment plant in an oil refinery factory. Industrial WAS coul be successfully detraded in a batch digestion with ATCC 31197. The stability of the digestion process with ATCC 31197 was successfully verified by semi-continuous (fill-and-draw) digestion experiment. From the results of this study, it was shown that the thermophilic aerobic digestion process with ATCC 31197 could efficiently be applied to the degradation of industrial WAS.

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