Rapid hydrogen generation from cotton wastes by mean of dark fermentation

Abstract

AbstractDark fermentation of textile wastes is discussed in the paper. In the experiment cotton wastes were fermented. Before fermentation the cotton was hydrolyzed using 0.1 M HCl acidic solution. The inoculum was pretreated by means of heat shock for 0.5 h at 105 °C. The fermentation was carried out under mesophilic conditions at a load of 5 g VSS/L, and pH 5. Oxygen was added in small quantities during fermentation. The oxygen flow rates (OFR) were between 0.3 and 1.0 mL/h. The fermentation was carried out for a few days at temperatures between 40 and 43 °C. Hydrogenesis prevailed at the lower temperature (40 °C) and methanogenesis at the higher (43 °C). Conversion of cotton waste to methane (3.4%) was slightly higher than conversion to hydrogen (2.6%). The highest hydrogen production was obtained for OFR 0.8 mL/h and the percentage of hydrogen in biogas was 43%. At higher temperatures (43 °C) no hydrogen production was observed