Establishment and assessment of a novel cleaner production process of corn grain fuel ethanol.
An integrated corn ethanol-methane fermentation system was proposed to solve the problem of stillage handling, where thin stillage was treated by anaerobic digestion and then reused to make mash for the following ethanol fermentation. This system was evaluated at laboratory and pilot scale. Anaerobic digestion of thin stillage ran steadily with total chemical oxygen demand removal efficiency of 98% at laboratory scale and 97% at pilot scale. Ethanol production was not influenced by recycling anaerobic digestion effluent at laboratory and pilot scale. Compared with dried distillers' grains with solubles produced in conventional process, dried distillers' grains in the proposed system exhibited higher quality because of increased protein concentration and decreased salts concentration. Energetic assessment indicated that application of this novel process enhanced the net energy balance ratio from 1.26 (conventional process) to 1.76. In conclusion, the proposed system possessed technical advantage over the conventional process for corn fuel ethanol production.
The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
Ke
K
Wang
Jianhua
J
Zhang
Lei
L
Tang
Hongjian
H
Zhang
Guiying
G
Zhang
Xizhao
X
Yang
Pei
P
Liu
Zhonggui
Z
Mao
D000596:Amino Acids / Q000032:analysis; D000693:Anaerobiosis; D000821:Animal Feed; D056804:Biofuels / Q000032:analysis*; D018533:Biomass; D001709:Biotechnology / Q000379:methods*; D002241:Carbohydrates / Q000032:analysis; D000431:Ethanol / Q000138:chemical synthesis*; D005285:Fermentation; D007753:Laboratories; D010865:Pilot Projects; D012639:Seeds / Q000737:chemistry*; D013816:Thermodynamics; D003313:Zea mays / Q000737:chemistry*
D000596:Amino Acids; D056804:Biofuels; D002241:Carbohydrates; D000431:Ethanol
5-hydroxylmethylfurfural; ADE; ASBR; Anaerobic digestion; CSTR; Corn; DDG; DDGS; Energetic assessment; Ethanol fermentation; FOG; HMF; HPLC; HRT; NEB; SCOD; SMP; TCOD; TN; TP; Thin stillage; Total nitrogen; VFA; VS; WDG; anaerobic digestion effluent; anaerobic sequencing batch reactor; continuous stirred-tank reactor; dried distillers’ grains; dried distillers’ grains with solubles; fats, oils, and grease; high-performance liquid chromatography; hydraulic retention time; net energy balance; soluble chemical oxygen demand; soluble microbial products; total chemical oxygen demand; total phosphorus; volatile fatty acid; volatile solids; wet distillers’ grains