Abstract
Thermophilic bacteria pretreated sludge has drawn more Interest for hydrogen production, which was more economical (needs less energy), pollution-free (adding a reagent is not needed), and efficient than physico chemistry pretreated sludge Comparative studies between thermophilic bacteria (Bacillus sp AT07 1) and 65 degrees C heat pretreated sewage sludge have been conducted for hydrogen production It was concluded that using thermophilic bacteria pretreated sludge for hydrogen production (batch of TB) would produce the highest hydrogen yield of 16 3 mL/g of volatile solid (VS), and It increased by 12 9 26 4, and 52 3% compared to T + HB (65 degrees C heat pretreated sludge inoculated with Enterococcus sp LG1) T (65 degrees C heat pretreated sludge), and TB + HB (thermophilic bacteria pretreated sludge inoculated with Enterococcus sp LG1), respectively The lag time of TB was only 3 h The hydrogen concentration in the gas phase of TB + HB and T + HB was 66 2 and 67%, respectively, higher than that of TB and T These results demonstrated that different pretreatments and inoculations could influence the solubilization of sludge, the hydrogen yield, and the hydrogen concentration