Analysis of parameter effects on fermentative H2 production from cheese whey

Cheese whey (CW) is one of the most abundant by-products of cheese manufacturing, with~9.0 kg of CW beinggenerated perkg of cheese produced. Among the different optionsfor CW management, anaerobic digestion can be regarded as one of the most promising, being able to reduce the organic load of CW while harversting its energy content. Recently, an increasing attention has specifically been paid to dark fermentation of CWaimedatbiological H2production. In the present study, the effect of pH conditions and inoculum addition on H2production from CW was investigated under continuously stirred batch conditions by designing the experiments according to the principles of a factorial design. According to this approach, the set-point of the pH values of the system and the amount of inoculum added to CW werevaried over fourvalues. As the inoculum, the aerobic sludge from a wastewater treatment plant was used, after heat-shocking at 110 °C for 30 minutes so as to harvest the hydrogenogenic biomass. Process performance was evaluated in terms of H2production and substrate conversion efficiency, by twoprocess indicators: 1) amount and composition of the produced biogas evolution of the metabolic pathways, 2) evolution of substrate degradation, expressed as the removal total organic carbonand carbohydrates.