초록
Dissolved carbon dioxide (dCO<SUB>2</SUB>) evolved from Saccharomyces cerevisiae was measured, controlled and used to drive repeated batch operation for ethanol fermentation. The experiments were conducted at four glucose feeds (150, 200, 250 and 300g/l) under three dCO<SUB>2</SUB> control levels (no control, 750ppm and 1000ppm). Results showed that the evolution patterns of dCO<SUB>2</SUB> depend on the extent of glucose being utilized as well as the dCO<SUB>2</SUB> control level. Repeated batch was successfully operated for four glucose feeds under dCO<SUB>2</SUB> control. Controlling dCO<SUB>2</SUB> level at 750ppm, the self-cycling period for each repeated batch is 6.6+/-0.3, 7.3+/-0.2, 12.12+/-1.12, and 21.70+/-5.98h, as glucose feed changes from 150, 200, 250 and 300g/l, respectively. When dCO<SUB>2</SUB> level increases, the self-cycling period increases as well.