Abstract: The effects of various nutrients in fermentation broth on the volumetric liquid-phase mass transfer cofficient kLa were studied in a bubble column. The mathematical model for measuring kLa was modified. The correlation of kLa was derived theoretically as follows It was shown that the presence of macromolecular carbon source or nitrogen source decreased kLa, while that of urea and inorganic salts with low ion strength ( < 0.02kmol / m3) had no effect on kLa and the presence of glucose and inorganic salts with higher ion strength ( ≥0.02 kmol/m3) could increase kLa. Parameters of the correlation were determined according to the different effects of various nutrients. Values of kLa from the correlation agree well with the measured values.

摘要： 研究了发酵液中各种添加物质对液相体积传质系数的影响,对不稳态解吸平均浓度法测定传质系数的数学模型进行了修正,并从理论分析推导出传质系数的关联式.实验表明,大分子碳源、氮源能降低液相体积传质系数.尿素和离子强度低于0.02kmol/m~3的无机盐溶液对传质系数无影响,离子强度高于0.02kmol/m~3的无机盐和葡萄糖溶液能提高传质系数.根据各物质对传质系数的不同影响,分别确定出关联式中的各个参数.模型关联式与实验值吻合较好.