Removal of Hydrogen Sulfide, Ammonia, and Benzene by Fluidized Bed Reactor and Biofilter

KIM, CHONG-WOO,PARK, JIN-SU,CHO, SUNG-KI,OH, KWANG-JOONG,KIM, YOUNG-SIK,KIM, DONGUK 한국미생물 · 생명공학회 2003 Journal of microbiology and biotechnology Vol.13 No.2

In this study, hydrogen sulfide (H_2S), ammonia (NH_3), and benzene, which represent the major leather process plant, were removed using a fluidized bed bioreactor and biofilter including Thiobacillus sp. IW and a MY microbial consortium. The critical removal rate was 12 gm^-3h^-1 for H_2S, 11 gm^-3h^-1 for NH_3, and 28 gm^-3h^-1 for benzene by the fluidized bed bioreactor, and 8.5 gm^-3h^-1 for H_2S, 7 gm^-3h^-1 for NH_3 and 25 gm^-3h^-1 for benzene in the biofilter. The average removal efficiency of H_2S, NH_3, and benzene by continuous operation for over 30 days with the fluidized bed bioreactor was 95±3%, 99±1%, and 985%, respectively, whereas that with the biofilter was 96±4%, 95±4%, and 97±3%, respectively. Therefore, the critical removal rate of H_2S, NH_3 and benzene was higher in the fluidized bed bioreactor, whereas the removal efficiency on the continuous operation was similar in both bioreactors.

유동층 생물반응기를 이용한 우유폐수처리에 관한 연구

김봉섭(Bong Sub Kim),서명교(Myung Gyo Suh),박광식(Kwang Sik Park),서재신(Zae Sin Seo),허종화(Jong Wha Hur) 한국환경보건학회 1999 한국환경보건학회지 Vol.25 No.4

This study was carried to investigate the milk-wastewater treatment in batch and continuous fluidized-bed bioreactor containing active microorganism, Aspergillus niger KCTC 1231. The reactor was operated at 30℃. The COD removal efficiency and MLSS were measured to determine the performance of the fluidized-bed bioreactor by cell concentration, aeration rate, and organic loading rate, respectively. At conditions of 60 ㎖ cell concentration and 2.0LPM aeration rate, milk-wastewater showed the COD removal efficiency of 81.51% and MLSS of 43,562 mg/ℓ, Also the same conditions, at adding 80 ㎖ chitosan beads, the COD removal efficiency and MLSS were about 85.79% and 62,482.5 mg/ℓ, respectively. In case of organic loading rate 3.88 kgCOD/㎥·day, free cell and adding chitosan beads showed about 80∼85% and 85∼90% COD removal efficiency, respectively. It was showed that milk-wastewater treatment of fluidized-bed bioreactor with chitosan beads was about 5% more efficient.

Development and application of a procedure for evaluating the long-term integrity of membranes for the anaerobic fluidized membrane bioreactor (AFMBR)

Shin, Chungheon,Kim, Kihyun,McCarty, Perry L.,Kim, Jeonghwan,Bae, Jaeho IWA Publishing 2016 Water Science & Technology Vol.74 No.2

<P>A bench-scale short-term test, developed to predict the long-term integrity of membranes with potential for use in anaerobic fluidized-bed membrane bioreactors, was used to evaluate several commercial hollow-fiber membranes. It was found that membrane performance varied widely, some membranes failing much more rapidly than others. Also found was that larger sizes of the fluidized media, in this case granular activated carbon (GAC), severely affected membrane structural integrity more than did smaller sizes, as did the method used for membrane attachment. Within the limits studied, the GAC packing ratio had only a minor impact. A decrease in membrane permeability that sometimes resulted during the testing and was caused by the deposition of fine GAC particles could be eliminated without membrane damage through simultaneous chemical cleaning and sonication. This new testing procedure should be useful for selecting membranes and reactor operating conditions to better ensure long-term operating performance of anaerobic fluidized-bed membrane bioreactors.</P>

Modelling approach to better control biofouling in fluidized bed membrane bioreactor for wastewater treatment

Charfi, Amine,Aslam, Muhammad,Kim, Jeonghwan Elsevier 2018 CHEMOSPHERE - Vol.191 No.-

<P><B>Abstract</B></P> <P>A mathematical model has been developed to better understand fouling mitigation mechanisms in particle-sparged membrane bioreactor. The model developed herein assumes two fouling mechanisms, (i) the pore blocking leading to the decrease in membrane surface porosity and (ii) the progressive development of compressible cake layer on the membrane surface. The model has been validated by comparison with <I>trans</I>-membrane pressure data registered from the bioreactor filtering a synthetic solution consisting of bentonite, sodium alginate and bovin serum albumine (BSA). Two nonporous media have been tested, Polyethylene terephthalate (PET) beads and silica particles with different dosage (0, 10, 30, 50 and 70% (v/v)). Compared to the experimental data, the model shows satisfactory fitting with R<SUP>2</SUP> ≥ 93%. For both media tested, an optimal dosage to minimize fouling rate was observed at 50% (v/v). Even if both fouling mechanisms have been mitigated by adding fluidized media, pore blocking was more pronounced than cake formation. Moreover, better pore blocking mitigation was observed with PET media (50% (v/v)) having bigger size and lower density than silica particles.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Model was developed to better understand fouling in fluidized membrane bioreactor. </LI> <LI> Pore blockage models agreed well with results with different media dosage. </LI> <LI> Optimal dosage of non-adsorbing media (50% (v/v)) to minimize fouling was observed. </LI> <LI> PET media with bigger size and lower density allowed better pore blocking mitigation. </LI> </UL> </P>

삼상 순환 유동층 생물반응기에서 열전달 계수

강태규,송평섭,최길수,조용준,강용,최호석,김상돈 한국화학공학회 2002 Korean Chemical Engineering Research(HWAHAK KONGHA Vol.40 No.5

직경이 0.102m이고 높이가 1.0m인 기체-액체 순환 및 삼상 순환유동층 생물반응기의 상승관에서 열전달 특성을 고찰하였다. 기체 및 액체의 유속 그리고 생물막 담체의 체류량이 상승관 내부의 수직 열원과 반응기 사이의 열전달 계수에 미치는 영향을 결정하였다. 기체-액체 순환 반응기에서 열전달 계수는 기체의 유속이 증가함에 따라 증가하였으나 액체 유속의 증가에 따라서는 약간 증가하였다. 삼상 순환유동층 생물반응기에서 열전달 계수는 기체의 유속과 유동 생물막 매체의 체류량이 증가함에 따라 증가하였으나 액체의 유속이 증가함에 따라서는 약간 증가하였다. 본 연구의 실험 범위에서 이들 열전달 계수는 실험 조작 변수의 상관식으로 잘 나타낼 수 있었다. Heat transfer characteristics have been investigated in the riser of gas-liquid circulation and three-phase circulating fluidized-bed bioreactors whose diameter and height are 0.102m and 1.0m, respectively. Effects of gas and liquid velocities and holdup of fluidized biofilm media on the heat transfer coefficient between the immersed vertical heater and the bed have been determined. The heat transfer coefficient in the gas-liquid circulation reactor increases with increasing gas velocity, but increases only slightly with increasing liquid velocity. The h(heat transfer coefficient) value in the three-phase circulating fluidized-bed bioreactor also increases with increasing gas velocity or holdup of fluidized biofilm media, but it increases only slightly with liquid velocity. The value of heat transfer coefficient has been well correlated in terms of operating variables.

저밀도입자를 함유하는 삼상 유동층의 Gas Holdup 특성

이명섭 永同工科大學校 1996 硏究論叢 Vol.2 No.1

저밀도입자를 함유하는 삼상 유동층 및 기포탑의 gas holdup 특성을 압력분포 측정법을 이용하여 조사하였다. Gas holdup에 미치는 기체 및 액체의 유속, 고체입자의 밀도 및 크기의 영향이 조사되었다. Gas holdup 은 기포탑 및 삼상유동층에서 기체유속에 따라 모두 증가하는 결과를 나타내었으나, 액체유속의 증가에 따라서는 기포탑의 경우는 액체유속의 증가와는 거의 독립적인데 반하여 삼상유동층의 경우는 액체유속의 증가에 따라 감소하였다. Gas holdup 은 기포탑의 경우 Akita 등의 결과와 일치하였으나 삼상유동층의 경우는 일치하지 않음을 나타내었다. 이에 본 연구에서는 기포의 흐름에 수반되는 drift line을 고려한 새로운 실험식을 도입하여 본 실험의 결과와 비교한 바 실험식을 통하여 계산한 값이 실험결과와 잘 일치하였다. The Characteristics of gas holdup was investigated in a three-phase fluidized bed containing low density particles by using the method of pressure profiles measurement in the bed. It was investigated that the effect of gas and liquid velocity, density and size of the solid particles on the characteristics of the gas holdup. Gas holdup increased with the gas velocity in both the three-phase fluidized bed and the bubble column, however, while it was independent with the liquid velocity in the bubble column, it decreased in the three-phase fluidized bed. In the bubble column, gas holdup was agree with the result calculated from Akita's relation for the bubble column. In three-phase fluidized bed, however, it was not agree with the relation. In the present study, gas holdup was compared with the result calculated from the relation which was derived by the author using the drift line model. The value from the experiment was agee with that the value calculated from the drift line model.

Sensitivity Analysis of the Model Parameters for an Anaerobic Fluidized Bed Bioreactor

석종혁 한국수처리학회 2019 한국수처리학회지 Vol.27 No.1

Sensitivity analysis for the model parameters determined from the experimental data of the propylene glycol biomethanization process was presented. The mathematical model developed was assumed as a completely mixed stirred tank reactor(CMSTR) and composed of 13 differential equations associated with 18 parameters. Basic model parameters determined from an initial experimental data set using one bioreactor were then verified with the results from a second bioreactor. Unknown parameters were then estimated in a sequential manner by means of an optimization technique. The computational effort can be significantly reduced by obtaining the most sensitive parameter combinations, where the eigenvector corresponding to the largest eigenvalue indicates the most sensitive direction. This parameter combination technique was successfully applied to the sensitivity analysis of the CMSTR model parameters and the results were verified using the novel technique developed for this purpose. The result indicates that parameters related to the propionate significantly influence the model behavior. In general, any decay coefficients are shown to be insignificant.

투과증발과 결합된 에탄올 발효 공정의 모델링 및 특성

최은수,김진현,유영제 한국산업미생물학회 1992 한국미생물·생명공학회지 Vol.20 No.4

에탄올발효에서 에탄올은 세포의 성장 및 에탄올 생합성에 저해작용을 하는 것으로 알려져 있다. 이러한 저해작용을 감소시켜주기 위하여 에탄올을 선택적으로 분리하는 투과증발법을 이용하였다. 실리콘-폴리술폰 복합막을 제조하여 사용하였는데 이 막은 유입액의 에탄올 농도가 25g/ℓ, 온도가 30℃, 막하부의 압력이 10㎜Hg일 때 에탄올의 선택도가 약 4이었으며, 총 투과유속은 300g/㎡h이었다. 에탄올 발효는 Saccharomyces cerevisiae를 Ca-alginate에 고정화시켜 유동층 생물반응기에 접종하여 수행하였고, 이 반응기를 투과증발장치와 연결한 혼합공정을 구성하였는데, 혼합공정의 경우 발효배지의 에탄올농도는 막을 연결하지 않았을 때보다 감소하여 저해작용을 감소시키고 생산성을 향상시켰다. 혼합공정에 대하여 제안한 모델식으로부터 얻은 모사결과는 실험결과와 잘 일치하였다. 모델식을 이용하여 수치모사한 결과 막면적, 공급기질의 농도 그리고 고정화세포내 세포농도의 증가는 에탄올 생산성을 높이는 중요한 요인임을 알 수 있었다. Pervaporation which is capable of removing ethanol selectively was adopted to reduce the ethanol inhibition and in situ recovery of ethanol in ethanol fermentation. The composite membrane made of silicone and polysulfone was used to separate the ethanol selectively. The ethanol selectivity of the membrane was about 4 and the total flux was 300 g/㎡ h at 30℃ and 10 ㎜Hg for 25g/ℓ of feed concentration. Saccharomyces cerevisiae entrapped within Ca-alginate gels was employed for ethanol fermentations in a fluidized-bed bioreactor. The pervaporation membrane unit and fluidized-bed bioreactor were combined into one system. The proposed model equations for the combined system showed good accordances with the experimental results. It was found from the simulation results that the ethanol concentration in the broth for the combined system was lower than that for the continuous fermentation system without a membrane unit. Ethanol productivity can be thus increased by employing the combined system.

Gas Holdup and Gas-Liquid Mass Transfer in Three-Phase Circulating Fluidized-Bed Bioreactors

Sung Mo Son,Suk Hwan Kang,Tae Gyu Kang,Pyung Seob Song,Uk Yeong Kim,Yong Kang,Hyoung Ku Kang 한국공업화학회 2007 Journal of Industrial and Engineering Chemistry Vol.13 No.1

Trends in Monoclonal Antibody Production Using Various Bioreactor Systems

( I. Jyothilekshmi ),( N. S. Jayaprakash ) 한국미생물생명공학회(구 한국산업미생물학회) 2021 Journal of microbiology and biotechnology Vol.31 No.3

Monoclonal antibodies are widely used as diagnostic reagents and for therapeutic purposes, and their demand is increasing extensively. To produce these proteins in sufficient quantities for commercial use, it is necessary to raise the output by scaling up the production processes. This review describes recent trends in high-density cell culture systems established for monoclonal antibody production that are excellent methods to scale up from the lab-scale cell culture. Among the reactors, hollow fiber bioreactors contribute to a major part of high-density cell culture as they can provide a tremendous amount of surface area in a small volume for cell growth. As an alternative to hollow fiber reactors, a novel disposable bioreactor has been developed, which consists of a polymer-based supermacroporous material, cryogel, as a matrix for cell growth. Packed bed systems and disposable wave bioreactors have also been introduced for high cell density culture. These developments in high-density cell culture systems have led to the monoclonal antibody production in an economically favourable manner and made monoclonal antibodies one of the dominant therapeutic and diagnostic proteins in biopharmaceutical industry.