Influence of nitrogen sources on ethanol fermentation in an integrated ethanol-methane fermentation system.
An integrated ethanol-methane fermentation system was proposed to resolve wastewater pollution in cassava ethanol production. In the integrated system, wastewater originating from ethanol distillation was treated by two-stage anaerobic digestion and then used in medium for the next batch of ethanol fermentation. Ammonium and other components in the effluent promoted yeast growth and fermentation rate but did not increase the yield of ethanol. Fermentations with the effluent as the nitrogen source showed higher growth and ethanol production rates (0.215 h(-1) and 1.276 g/L/h, respectively) than urea that resulted in corresponding rates of 0.176 h(-1) and 0.985 g/L/h, respectively. Results indicated that anaerobic digestion effluent can be used as nitrogen source for the ethanol fermentation instead of urea in the ethanol-methane fermentation system.
The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
Ke
K
Wang
Zhonggui
Z
Mao
Chengming
C
Zhang
Jianhua
J
Zhang
Hongjian
H
Zhang
Lei
L
Tang
D000596:Amino Acids / Q000032:analysis; D000693:Anaerobiosis; D061249:Batch Cell Culture Techniques; D001709:Biotechnology / Q000379:methods*; D011232:Chemical Precipitation / Q000187:drug effects; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation / Q000187:drug effects*; D006863:Hydrogen-Ion Concentration / Q000187:drug effects; D008697:Methane / Q000378:metabolism*; D009584:Nitrogen / Q000494:pharmacology*; D000644:Quaternary Ammonium Compounds / Q000302:isolation & purification; D012441:Saccharomyces cerevisiae / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism
D000596:Amino Acids; D000644:Quaternary Ammonium Compounds; D000431:Ethanol; D009584:Nitrogen; D008697:Methane