自絮凝酵母SPSC01悬浮液的流变行为

Rheology of self-flocculating yeast suspensions of SPSC01

用旋转黏度计测定了自絮凝颗粒酵母悬浮液的流变特性,并考察了其流变特性的影响因素,如菌体生物量、葡萄糖质量浓度、温度等。结果表明:自絮凝颗粒酵母悬浮液呈假塑性非牛顿流体,其流变特性服从幂律指数模型,随着菌体浓度的增大,稠度系数增大,流动行为指数减小;絮凝悬浮液的表观黏度随着糖浓度的增加有所增加,同一生物量下稠度系数k随着糖浓度的增加而增加,流动行为指数n随着糖浓度的增加变化很小,悬浮液的表观黏度随着温度的升高而降低;相同生物量下的流变指数随温度的升高而升高,而稠度系数随温度升高有所下降。

Rheological behaviors of self-flocculating yeast suspensions were investigated using a rotating cylinder viscometer. Effects of factors, such as biomass concentrations, glucose contents and temperature on the rheological properties were also investigated. Experimental results revealed that the self-flocculating yeast suspensions were pseudoplastic non-Newtonian fluid when the biomass concentration was higher than 15 g/L and the rheological characteristics could be expressed by power-law index model. The consistency coefficient k increased and the flow behavior index n decreased with the increase of biomass concentration. The self-flocculating yeast suspensions behaved Newtonian when the biomass concentrations was less than 15 g/L. The apparent viscosity and the consistency index k of the self-flocculating yeast suspension increased and the flow behavior index n decreased when the sugar concentration was increased at a constant biomass concentration. The apparent viscosity and the consistency index k of the self-flocculating yeast suspension decreased and the flow behavior index n increased when temperature was increased for a constant biomass concentration.