초록
To alleviate the problems of low substrate loading, nonisothermal, end-product inhibition of ethanol during the simultaneous saccharification and fermentation, a nonisothermal simultaneous solid state saccharification, fermentation, and separation (NSSSFS) process was investigated; one novel pilot scale nonisothermal simultaneous solid state enzymatic saccharification and fermentation coupled with CO<SUB>2</SUB> gas stripping loop system was invented and tested. The optimal pretreatment condition of steam-explosion was 1.5MPa for 5min in industrial level. In the NSSSFS, enzymatic saccharification and fermentation proceeded at around 50<SUP>o</SUP>C and 37<SUP>o</SUP>C, respectively, and were coupled together by the hydrolyzate loop; glucose from enzymatic saccharification was timely consumed by yeast, and the formed ethanol was separated online by CO<SUB>2</SUB> gas stripping coupled with adsorption of activated carbon; the solids substrate loading reached 25%; ethanol yields from 18.96% to 30.29% were obtained in fermentation depending on the materials tested. Based on the pilot level of 300L fermenter, a novel industrial-level of 110m<SUP>3</SUP> solid state enzymatic saccharification, fermentation and ethanol separation plant had been successfully established and operated. The NSSSFS was a novel and feasible engineering solution to the inherent problems of simultaneous saccharification and fermentation, which would be used in large scale and in industrial production of ethanol.