The cell growth kinetics of S.cerevisiae in the pervaporation membrane bioreactor were investigated under two operation modes:fer-mentation coupled with intermittent separation and fermentation coupled with continuous separation. The experiments for the two operating modes lasted for 264 h. The maximum cell concentration of the two modes were 15.56 g/L, 26.73 g/L, and ethanol productivity were 1.79 g/L·h, 2.31 g/L·h, respectively. Both impermeable metabolites and cell death became the dominant factors on cell growth, because etha-nol and other permeable species were removed simultaneously by the membrane. The kinetics model of cell growth was developed by correlat-ing secondary metabolites concentration with ethanol production and with the description of cell death rate as a function of cell concentration and fermentation time. The theoretical model was highly coincident with the experimental data according to non-linear analysis, and the correla-tion coefficients were above 0.968.%采用发酵-间歇分离、发酵-连续分离两种操作模式,研究了渗透汽化膜生物反应器中酿酒酵母细胞在乙醇发酵过程中的生长特性.两种操作模式下均持续发酵264 h,细胞的最大浓度分别为15.56 g/L、26.73 g/L,乙醇生产强度分别为1.79 g/L·h、2.31 g/L·h.由于乙醇及其他透过性产物被膜即时分离,非透过性的发酵副产物和细胞死亡就成为影响细胞生长的关键因素.将膜上游副产物浓度与乙醇生产相关联并将细胞的死亡速率作为细胞浓度和发酵时间的函数,建立了描述细胞生长过程的动力学模型.通过非线性拟合发现动力学模型与实验数据吻合度较高,拟合相关系数的平方均大于0.968.
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