Continuous ethanol production using cell recycle with a settler

Boks, P. A. de; Eybergen, G. C. van

doi:10.1007/bf00133437

Cited by 19 publications

(3 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Floc-forming variants of Z. mobilis have been isolated from nature (3,21) and have been recently reported to arise spontaneously in immobilized-cell (1) and tower (16) fermentors and after chemical mutagenesis (19). Despite this, little is known about the physiology of the cells or the basis of flocculation.…”

mentioning

confidence: 99%

Controlling Morphological Instability of Zymomonas mobilis Strains in Continuous Culture

Fein

Zawadzki

Lawford

et al. 1983

Appl Environ Microbiol

View full text Add to dashboard Cite

Growth of Zymomonas mobilis ATCC 29191 and CP4 in a continuous stirred tank fermentor resulted in the selection of stable flocculating variants. Factors responsible for enhancing the system pressures selective for the morphological variants were identified. By incorporating some modifications into the design of the fermentor, it was possible to achieve steady-state operation of the chemostat with both wild-type and flocculating strains. Biochemical and microscopic studies were performed to elucidate the mechanism of flocculation in Z. mobilis .

show abstract

mentioning

confidence: 99%

Controlling Morphological Instability of Zymomonas mobilis Strains in Continuous Culture

Fein

Zawadzki

Lawford

et al. 1983

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…In order to solve this problem, various continuous processes have recently been suggested, including immobilized yeast cells using a carrier or packed bed fermentor and recirculating yeast cells using a separating device [18]. Continuous processes using a membrane, sedimentation tank, centrifuge, and high flocculating yeast were reported [19][20][21][22][23]. Although some literatures regarding the continuous production of bioethanol from filtered saccharification liquor have been previously reported [24][25][26], the continuous production of bioethanol with simultaneous saccharification and fermentation from starchy materials has rarely been reported so far.…”

Section: Introductionmentioning

confidence: 99%

Continuous Ethanol Production from Cassava Through Simultaneous Saccharification and Fermentation by Self-Flocculating Yeast Saccharomyces Cerevisiae CHFY0321

Choi¹,

Kang²,

Moon³

et al. 2009

Appl Biochem Biotechnol

View full text Add to dashboard Cite

In this study, a fermentor consisting of four linked stirred towers that can be used for simultaneous saccharification and fermentation (SSF) and for the accumulation of cell mass was applied to the continuous production of ethanol using cassava as the starchy material. For the continuous process with SSF, the pretreated cassava liquor and saccharification enzyme at total sugar concentrations of 175 g/L and 195 g/L were continuously fed to the fermentor with dilution rates of 0.014, 0.021, 0.031, 0.042, and 0.05 h(-1). Considering the maximum saccharification time, the highest volumetric productivity and ethanol yield were observed at a dilution rate of 0.042 h(-1). At dilution rates in the range of 0.014 h(-1) to 0.042 h(-1), high production rates were observed, and the yeast in the first to fourth fermentor showed long-term stability for 2 months with good performance. Under the optimal culture conditions with a feed sugar concentration of 195 g/L and dilution rate of 0.042 h(-1), the ethanol volumetric productivity and ethanol yield were 3.58 g/L x h and 86.2%, respectively. The cell concentrations in the first to fourth stirred tower fermentors were 74.3, 71.5, 71.2, and 70.1 g dry cell/L, respectively. The self-flocculating yeast, Saccharomyces cerevisiae CHFY0321, developed by our group showed excellent fermentation results under continuous ethanol production.

show abstract

“…Considerable research is now being directed at the genetic manipulation of yeasts through amplification of the FLO gene in order to improve and stabilize their ability to flocculate (Johnston and Obermann, 1979). With Zymomonas other authors have reported that flocculent strains can be isolated from the natural environment (Millis, 1956;Swings and De Ley, 1977) and a recent paper reports a kinetic evaluation of one of these strains (de Boks and van Eybergen, 1981).…”

Section: Introductionmentioning

confidence: 99%