Riboflavin (vitamin B2) is a nutrient that is used as a food additive (mainly in animal feed, but also in breakfast cereal). It can be produced by fermentation of glucose using strains of the yeast species Candida fermata, as described in US 5,164,303 (Heffner, Weaver, Yaris, & Burdzinski, 1992). Example IV in the patent gives the following yields in a 450 liter fed-batch fermentation tank operated at 30 °C and 40% of oxygen saturation. The glucose concentration was maintained above a critical level of 30 g/l by feeding additional 600 g/l glucose solution during the fermentation.
Design a reactor system to produce 40 metric tons per year of riboflavin using the strain given in the patent.