Biohydrogen production from buffalo slurry (BS) co-fermented with cheese whey (CW) and crude glycerol (CG) was investigated using a suitable microbial community (F210) as inoculum. Mixture Design was used to find the optimal composition (%) of the three substrate components and to investigate the effect of the mixing ratio on Bio-H2yields. Maximum H2yield estimated through the model was around 117 mL H2/g VSadded, while the maximum experimentally detected was 111.6 ± 21.8 mL H2/g VSadded, obtained for a mixing ratio of substrate composition of 66% BS and 33% CW (R2= 0.962; p-value = 0.0001). CW was clearly the most suitable substrate (with a relative contribution higher than 46%), but led to a rapid drop in pH from 6.5 to 4, while BS showed high buffering capacity by maintaining the pH above 6. Interestingly, the co-digestion of the different substrates decreased the H2production lag phase λ; in particular the presence of BS shortened the lag period (λ < 3 h) and increased the degradation efficiency of CG. The results demonstrate the usefulness of the mixture design for finding the optimal substrate composition, using BS as co-fermentation substrate to obtain high H2production yields. Moreover the response surface shows the possibility of mixing the substrates in different ways, while maintaining H2production within an optimum range: 105-117 mL H2/g VSadded. This might offer a considerable advantage in the effective management of systems or processes, in which the substrates availability may change over the time.
All Science Journal Classification (ASJC) codes
- Renewable Energy, Sustainability and the Environment
- Fuel Technology
- Condensed Matter Physics
- Energy Engineering and Power Technology
Marone, A., Varrone, C., Fiocchetti, F., Giussani, B., Izzo, G., Mentuccia, L., ... Signorini, A. (2015). Optimization of substrate composition for biohydrogen production from buffalo slurry co-fermented with cheese whey and crude glycerol, using microbial mixed culture. International Journal of Hydrogen Energy, 40(1), 209 - 218. https://doi.org/10.1016/j.ijhydene.2014.11.008