Semi-continuous and Continuous Cultivation of Microalgae-sludge for Artificial Digested Food Wastes Leachate Treatment

( Shan Zhang ),( Hyeon Jeong Hwang ),( Sun-jin Hwang ) 한국폐기물자원순환학회(구 한국폐기물학회) 2015 한국폐기물자원순환학회 춘계학술발표논문집 Vol.2015 No.-

This study investigated the semi-continuous and continuous cultivation of microalgae-sludge for artificial digested food wastes leachate treatment, and the effect of hydraulic retention times(HRT) on microalgae growth and nutrient removal. In this study, two reactors were examined the HRTs from 4 to 1 day, the Chlorella vulgaris cell density of semi-continuous and continuous cultivation reached a maximum value at HRT 3 day, then decreasing HRT to 2 day and 1 day the Chlorella vulgaris cell density was decreased. The maximum Chlorella vulgaris cell density in semi-continuous cultivation was 1.4 times higher than continuous cultivation. The maximum NH_4-N, PO_4-P removal efficiency was 100%, 75.7% with HRT of 3 day in semi-continuous cultivation, while 96.5%, 65.7% with HRT of 4 day in continuous cultivation. These results indicate that semi-continuous cultivation is more suitable than continuous cultivation. And the effect of increased light intensity from 100 μmol/m²/s to 400 μmol/m²/s was also evaluated, as the result, increased light intensity improved Chlorella vulgaris cell growth and nutrient removal.

Semi-continuous and Continuous Cultivation of Microalgae-sludge for Artificial Digested Food Wastes Leachate Treatment

Shan Zhang,Hyeon Jeong Hwang,Sun-Jin Hwang 한국폐기물자원순환학회 2015 한국폐기물자원순환학회 학술대회 Vol.2015 No.05

This study investigated the semi-continuous and continuous cultivation of microalgae-sludge for artificial digested food wastes leachate treatment, and the effect of hydraulic retention times(HRT) on microalgae growth and nutrient removal. In this study, two reactors were examined the HRTs from 4 to 1 day, the Chlorella vulgaris cell density of semi-continuous and continuous cultivation reached a maximum value at HRT 3 day, then decreasing HRT to 2 day and 1 day the Chlorella vulgaris cell density was decreased. The maximum Chlorella vulgaris cell density in semi-continuous cultivation was 1.4 times higher than continuous cultivation. The maximum NH4-N, PO4-P removal efficiency was 100%, 75.7% with HRT of 3 day in semi-continuous cultivation, while 96.5%, 65.7% with HRT of 4 day in continuous cultivation. These results indicate that semi-continuous cultivation is more suitable than continuous cultivation. And the effect of increased light intensity from 100 μmol/m²/s to 400 μmol/m²/s was also evaluated, as the result, increased light intensity improved Chlorella vulgaris cell growth and nutrient removal.

혼합영양 배양조건에서의 Anabena 배양을 위한 유기탄소(acetate 종류 및 농도) 선정 연구

홍카이,고시원,이태윤,Hong, Kai,Gao, Siyuan,Lee, Taeyoon 한국화학공학회 2018 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.56 No.1

본 연구는 혼합영양 배양 조건에서 acetate의 주입이 Anabena azollae의 성장에 미치는 영향을 파악하기 위해 수행되었다. 4가지 종류의 acetate 중 ethyle acetate가 Anabena azollae의 성장에 가장 효과적이라고 밝혀졌으며, 주입한 ethyle acetate의 농도가 증가할수록 성장속도는 증가하는 것을 확인하였다. 40 mM의 ethyl acetate의 경우 비성장속도는 $0.979day^{-1}$, 최대바이오매스 생산성은 $0.293g\;L^{-1}\;d^{-1}$로 본 연구에서 배양속도가 가장 빠른 것으로 판명되었다. Acetic acid와 butyl acetate의 경우 Anabena azollae 성장을 방해하는 것으로 나타났다. Aetration의 경우 0.54 vvm에서 성장속도가 가장 빨랐다. 반연속배양에서는 aeration 실험이 끝난 후 연속하여 ethyle acetate 주입을 하여 배양을 하였다. 회분식실험에 비해 반연속배양에서의 비성장속도와 최대바이오매스 생산성은 모두 감소하였지만 최대 농도는 5.91 g/L로 가장 큰 값을 나타내었다. The main objective of this study was to evaluate the effects of acetate on the cultivation of anabena under mixotrophic condition. Four different types of acetates were used for the anebena cultivation. Among them, ethyl acetate was found to be the most effective and the growth rates linearly increased as the amount of ethyl acetate increased. When 40 mM of ethyl acetate was used, the highest values of specific growth rate of $0.979day^{-1}$ and maximum biomass productivity of $0.293g\;L^{-1}\;d^{-1}$ were obtained. On the contrary, input of acetic acid and butyl acetate inhibited the growth of anabena. For aeration tests, 0.54 vvm was optimum for anabena cultivation. For a semi-continuous cultivation test, ethyl acetate was used after 0.54 vvm test was finished. Then, test continued under 0.54 vvm and 40 mM of ethyl acetate. Lower specific growth rate and maximum biomass productivity were obtained compared to those from batch cultivation tests. However, the greatest maximum concentration of 5.91 g/L was obtained during the semi-continuous cultivation test.

생강연작재배지에서 Pythium zingiberum 경감을 위한 녹비작물 재배효과

정유진,노일섭,김용권,강권규 한국자원식물학회 2015 한국자원식물학회지 Vol.28 No.2

This experiment was carried out to evaluate the effects of green manure crops on the changes of chemical properties and microorganisms in soil of continuous ginger cultivation. The biomass and nitrogen absorption of green manure crop were the highest in crimson clover. After cropping, soil phosphate content was the lowest in orchard grass, however, T-N content was the highest of hairy vetch > crimson clover > orchard grass. Also real-time PCR analysis was conducted to measure density of Pythium zingiberum in soil of before and after incorporation of green manure crop. Density of P. zingiberum was the lowest of all the green manures. In this results are summarized that green manure cropping reduced salt accumulation and density of P. zingiberum in continuous ginger cultivation. 생강연작재배지 토양에 녹비작물의 재배가 토양 양분의 변화와 뿌리썩음병원균 경감효과를 알기위해 헤어리베치, 크림손클로버, 오차드글라스를 80일간 재배 후, 토양에 환원하여 토양분석 및 real-time PCR 분석한 결과는 다음과 같다. 녹비작물의 생육은 크림손클로버가 가장 좋았으며, 질수흡수량은 크림손클로버가 가장 높게 나타났으며, 토양의 인산함량은 오차드글라스가 가장 낮게 나타났다. T-N 함량은 헤어리벳치 > 크림손클로버 > 오차드글라스 순으로 나타났다. 또한 토양 내 뿌리썩음 병원균 밀도분석을 위해 Pythium zingiberum 균 특이5.8S rDNA를 이용하여 real-time PCR 분석한 결과 헤어리베치, 오차드그라스 및 크림손클로버 처리의 Ct값은 대조구보다낮게 나타났다. 이상의 결과를 요약해볼 때 생강연작재배지에서 녹비처리 후 토양은 대조구에 비해 EC가 감소되고, 몇 몇 무기성분은 증가하였으며, 뿌리썩음 병원균 밀도는 감소하였다

Continuous production of poly(3-hydroxybutyrate-co-3-hydroxyvalerate): Effects of C/N ratio and dilution rate on HB/HV ratio

Shwu-Tzy Wu,Yi-Chun Lin,Jui-Rze Too 한국화학공학회 2009 Korean Journal of Chemical Engineering Vol.26 No.2

Ralstonia eutropha was cultivated in a continuous stirred fermenter with various C/N ratios (20, 30, and 40), dilution rates, and organic salt substrates (sodium propionate or sodium valerate) to explore the microbial growth and the poly(3HB-co-3HV) accumulation. When sodium propionate was used as the secondary carbon source, the HB/HV molar ratio at various C/N ratios and dilution rates did not change appreciably (approximately 90 : 10). The highest poly(3HB-co-3HV) content in biomass (41.8%) and poly(3HB-co-3HV) productivity (0.100 g/(L·h)) occurred under the condition with a C/N ratio of 20 and dilution rate of 0.06 h−1. When sodium valerate was used as the secondary carbon source, the productivity of poly(3HB-co-3HV) increased with increasing dilution rate for the C/N ratio of 30 and 40. The average HB/HV molar ratio ranged from 48 : 52 to 78 : 32. The feeding of sodium valerate promoted the accumulation of HV better than feeding sodium propionate did. This study shows that a potential strategy of manipulating by both C/N ratio and dilution rate could be used to control the HV unit fraction in poly(3HB-co-3HV) in a continuous cultivation.

지속적 바이오매스 생산을 위한 클로렐라 반연속 배양 연구

최보람(Bo Ra Choi),임준혁(Jun Hyuk Lim),이제근(Jae Keun Lee),이태윤(Tae Yoon Lee) 大韓環境工學會 2012 대한환경공학회지 Vol.34 No.8

본 연구는 담수미세조류의 일종인 클로렐라를 적색 발광다이오드를 이용하여 효율적으로 반연속 배양하기 위한 조건을 찾기 위해 수행되었다. 클로렐라 배양에 가장 효율적인 적색 LED를 사용하여 반연속배양을 실시하였으며, 배양 중 인과 질소가 급격히 감소하였으며 이는 클로렐라의 성장과 반비례의 관계를 보여 주었다. 효율적인 반연속 배양을 위해 인과 질소의 농도를 증가시킨 배지를 사용하여 배지교체 주기를 연장시켜 배양 효율성을 높였다. 배지교체 시 클로렐라의 셀 농도는 지속적으로 증가하였으나, 셀 크기는 감소하였다. 셀 농도와 셀 크기를 고려할 때 배양 전과정을 통해 생산되는 바이오매스의 양은 일정하게 유지되었다. This study was performed to determine optimum conditions of semi-continuous cultivation of chlorella sp. FC-21 cultivated under red light emitting diode (LED). Semi-continuous cultivation was conducted using red LED because red LED was found to be the best light source for chlorella sp. FC-21. During cultivation, phosphate and nitrogen were quickly diminished where cell concentration of chlorella was inversely proportional to the concentrations of phosphate and nitrogen in culture solution. To increase the period of dilution of culture solution, additional amounts of phosphate and nitrogen were inserted in the culture solution to increase the concentrations of phosphate and nitrogen. The cell concentrations of chlorella increased in the modified culture, but cell diameter was diminished as the dilution of culture was periodically conducted. When considered the cell concentration and cell diameter during the cultivation, amount of biomass produced was maintained constant.

Development of Efficient Screening Tool for Highly-Productive Microalgae Strains under Continuous Cultivation System

Won-Sub SHIN,Min S. PARK,Jong-Hee KWON,Ji-Won YANG 한국생물공학회 2013 한국생물공학회 학술대회 Vol.2013 No.10

Enrichment as a Screening Method for a High-growth-rate Microalgal Strain under Continuous Cultivation System

신원섭,이한솔,성민규,황권택,정문근,권종희 한국생물공학회 2016 Biotechnology and Bioprocess Engineering Vol.21 No.2

Microalgae are a promising feedstock for renewable biodiesel production. High productivity of biodiesel production from microalgae is directly related to growth rate as well as lipid content of cells. In the present study, an enrichment process in a continuous cultivation system was developed to screen a high-growth-rate microalga from a mixed culture of microalgal species; Chlorella vulgaris, Chlorella protothecoides, and Chlamydomonas reinhardtii were used as test organisms for our experiments. The time-dependent washout of mixed microalgal pool was executed to successfully enrich the C. reinhardtii, which exhibits the higher growth rate than C. vulgaris and C. protothecoides under turbidostat conditions within 75 h. The domination of C. reinhardtii in the mixed culture was validated by on-line monitoring of growth rate and flowcytometric analysis. For the time-efficient production of microalgal biomass, this screening process has a high potential to segregate the fast-growing microalgal strains from the pool of various uncharacterized microalgal species and random mutants.

국제성함양과 관련된 프로그램 학습성과 평가체계 개선 연구

김복기,민상원,이건영,윤우영,강상희 한국공학교육학회 2009 공학교육연구 Vol.12 No.2

In this paper, a process model for assessing, evaluating and improving a program outcome on the cultivation of internationality is proposed by analyzing the present outcome assessment system. By setting up performance scaled levels and specifying the target level for the performance criterion, the proposed model can help programs to demonstrate effectively that each of their graduates meets the required the program outcome levels. By allowing effective Continuous Quality Improvement(CQI) for the performance criterion, the model can help save operational expense associated with running of the program CQI. In addition, it is discussed that one of the most important aspect is logical and objective approaches when establishing the outcome assessment system. It is hoped that the proposed model can ultimately help to meet the program outcomes requirements in the engineering accreditation criteria. 학습성과 평가체계를 분석하여, 이를 개선한 평가체 계의 모형을 국제성함양 학습성과를 예로 들어 제시 하였다. 제시된 학습성과 평가체계는 PC별로 수행수 준을 제시하고, 수행수준에 근거한 달성목표를 프로 그램 차원에서 설정하여, 학생이 졸업 시점에서 학습 성과 달성 여부를 용이하게 입증하는 체계를 갖추고 있다. 이렇게 평가체계를 구축함으로서 PC별로 CQI 를 운영할 수 있어 교육현장에서의 업무를 감소할 수 있을 것이다. 또한 이러한 평가체계 수립에서 고려 해야할 중요한 측면은 평가체계를 논리적이고 객관 적으로 구성해야 한다는 사실을 논의하였다. 본 논문 에서 제시한 학습성과 평가체계 모형은 대학 현장에 서 학생의 학습성과 달성을 입증할 수 있는 용이한 모형이 될 것이라 판단된다.

Comparative production of a monoclonal antibody specific for enrofloxacin in a stirred-tank bioreactor

Kittinan Komolpis,Chatchawan Udomchokmongkol,Songchan Phutong,Tanapat Palaga 한국공업화학회 2010 Journal of Industrial and Engineering Chemistry Vol.16 No.4

A hybridoma producing monoclonal antibody (MAb) specific for enrofloxacin was cultivated in a 2-L stirred-tank bioreactor in various modes and the performances of each mode were compared. In batch mode, a maximum viable cell and MAb concentration of 9.21 105 cells mL1 and 67.3 mg L1,respectively, were obtained. When the hybridoma was cultivated in a fed-batch culture with the addition of specific nutrients, no improvement in either the viable cell number or MAb concentration was observed. On the other hand, an increase in the production of toxic metabolites, i.e. ammonia and lactate, was observed with growth inhibition of the hybridoma cells occurring at ammonia and lactate concentrations of 2.0 mM and 2.0 g L1, respectively. However, the best performance of hybridoma cultivation was achieved in a perfusion culture mode using a spin filter, which was installed in the stirred-tank reactor as a cell retention device with a perfusion rate of 0.80 vvd. Under these conditions a steady viable cell concentration of 1.57 106 cells mL1 was obtained within five days with an overall productivity and yield of 73.7 mg L1 d1 and 61.4 mg d1, respectively, which was a significant increase over that attained with the batch process.