Comparison of biohydrogen production in fluidized bed bioreactors at room temperature and 35 °C

The aim of this work was to compare the H2 production in a lab scale anaerobic fluidized bed bioreactors (AFBRs) at two levels of operational temperature: ambient temperature (A) and 35 °C (M) and two organic volumetric loading rates Bv: 5 and 8 g sucrose/L.day, with a constant hydraulic residence time of 1 day.The increase of Bv from 5 to 8 g sucrose/L. day had a positive effect on the performance of our anaerobic fluidized bed reactors. In conclusion, at a Bv of 8 g sucrose/L.day the average performance of AFBR-A was superior to that of AFBR-M: 1.8 times for the H2 concentration in the biogas (54% and 31% respectively) and 2.2 times for the H2 productivity (920 and 427 NmLH2/Lbed .day, respectively). The H2 production in an AFBR operated at ambient temperature was superior to that of the mesophilic units and showed encouraging results for H2 production in submerged fermentation of moderate concentration of sucrose.

► We evaluated H2 production in AFBR at ambient temperature and 35 °C.
► Also we determined the effect of 2 organic loading rate Bv of sucrose.
► Increase of Bv of sucrose had a positive effect on bioreactor performance.
► H2 production at ambient temperature was superior to that of the mesophilic units.