With a feed sugar concentration of 220 g/L at the dilution rates
of 0.04, 0.15, 0.24 and 0.36 h1, the average ethanol concentrations
at steady state were 80.7, 61.7, 58.1 and 52.8 g/L, respectively. The
ethanol productivity increased approximately linearly with the
dilution rate. In this study, a maximum productivity of 19.0 g/
(L h) appeared at a dilution rate of 0.36 h1, which was 12.6-fold
higher than that of the batch fermentation. At a dilution rate of
0.04 h1 (HRT = 25 h), an ethanol concentration of 80.7 g/L was obtained,
which was comparable to the average concentration from