摘要
本文针对短梗霉多糖发酵过程,经研究建立了基于逻辑方程和Luedeking-Piret方程的动力学模型: dX/dt=px(1-X/X_m) dP/dt=m_1X+m_2(dX/dt) dS/dt=-b_1X—b_2(dX/dt)-b_3(dP/dt) 其流变特性由初始时的牛顿流体转变为典型的假塑性非牛顿流体并遵从指数方程,即:τ=γn随发酵过程进行,发酵液的表观粘度增大,体积氧传质系数减小。搅拌转速的增加有利于提高体积氧传质系数。流变指数n、稠度系数K、气液传质系数KLa与菌体浓度X、多糖浓度P、搅拌转速N及表观粘度η。间分别有如下经验方程: K=1.2×10^(-20X^(2.43) n=0.461(P/P_m)^(0.07)(X/X_m)^(0.0216) (kLaDi^2)/D=1.48×10~4((D_1N^2)/g)^(0.71)((η_w)/(η_a))^(0.15)
Fermentation kinetics,rheological property and oxygen mass transfer coefficient were studied during the fermentation process of Aureobasidium pullulans. A mathematical kinetic model based on the logistic equation and Luedeking-Piret model has been established with the experimental results. The rheology of the fermentation broth behaves as pseudoplastic non-Newtonian fluid.The oxygen mass transfer coefficient decreases during the fermentation process,an exponential equation has been postulated to describe the relationship among the oxygen mass transfer coefficient, the agitation speed and the apparent viscosity of the broth.
出处
《生物工程学报》
CAS
CSCD
北大核心
1990年第4期332-337,共6页
Chinese Journal of Biotechnology
关键词
短梗霉
微生物多糖
发酵
Pullulan, polysaccharide
fermentation
rheology
oxygen mass transfer