Fermentative hydrogen production potential from washing wastewater of beverage production process

In this study, anaerobic fermentation continuous system was carried out for hydrogen production by low concentration of beverage manufacture process wastewater, the most of the food industry wastewaters are in a relative low sugar concentration. The used substrate concentration of cultivation was 10 g total sugar/L, and hydraulic retention time (HRT) was 1 h for cultivation. Then the substrate concentration of experiments was lowered to 5 g total sugar/L, and HRT 1 h after the cultivation was completed. As a result, hydrogen production rate (HPR) was 11.39 ± 1.39 L/L/d, and yield was 0.30 ± 0.06 mol H2/mol hexose at HRT 1 h. The results showed that the hydrogen dark fermentation production in a continuous system is feasible at low concentrations for food industry wastewater. The sustainable biohydrogen production technology not only treat wastewater but also generate electricity from hydrogen via PEMFC. The SO32− on biohydrogen production, increased with increasing of sulfate concentration can inhibit microbial growth at excess concentration. Sulfate-reducing bacteria (SRB) will cause hydrogen gas converting hydrogen sulfide become poor hydrogen production efficiency.