Effect of substrate concentration on dark fermentation hydrogen production using an anaerobic fluidized bed reactor.
The effect of substrate (glucose) concentration on the stability and yield of a continuous fermentative process that produces hydrogen was studied. Four anaerobic fluidized bed reactors (AFBRs) were operated with a hydraulic retention time (HRT) from 1 to 8 h and an influent glucose concentration from 2 to 25 g L(-1). The reactors were inoculated with thermally pre-treated anaerobic sludge and operated at a temperature of 30 °C with an influent pH around 5.5 and an effluent pH of about 3.5. The AFBRs with a HRT of 2 h and a feed strength of 2, 4, and 10 g L(-1) showed satisfactory H(2) production performance, but the reactor fed with 25 g L(-1) of glucose did not. The highest hydrogen yield value was obtained in the reactor with a glucose concentration of 2 g L(-1) when it was operated at a HRT of 2 h. The maximum hydrogen production rate value was achieved in the reactor with a HRT of 1 h and a feed strength of 10 g L(-1). The AFBRs operated with glucose concentrations of 2 and 4 g L(-1) produced greater amounts of acetic and butyric acids, while AFBRs with higher glucose concentrations produced a greater amount of solvents.
Department of Hydraulic and Sanitation, University of São Paulo, São Carlos, São Paulo, Brazil.
Eduardo Lucena Cavalcante
EL
de Amorim
Leandro Takano
LT
Sader
Edson Luiz
EL
Silva
D019342:Acetic Acid / Q000494:pharmacology; D000693:Anaerobiosis / Q000187:drug effects / Q000528:radiation effects; D001419:Bacteria / Q000187:drug effects / Q000378:metabolism / Q000528:radiation effects; D018441:Biofilms / Q000187:drug effects / Q000254:growth & development / Q000528:radiation effects; D019149:Bioreactors / Q000382:microbiology*; D020148:Butyric Acid / Q000494:pharmacology; D003624:Darkness; D004305:Dose-Response Relationship, Drug; D000431:Ethanol / Q000494:pharmacology; D005285:Fermentation / Q000528:radiation effects*; D005947:Glucose / Q000378:metabolism* / Q000494:pharmacology; D006859:Hydrogen / Q000378:metabolism*; D012995:Solubility; D013997:Time Factors
D020148:Butyric Acid; D000431:Ethanol; D006859:Hydrogen; D005947:Glucose; D019342:Acetic Acid