초록
Factors affecting hydrogen production from the co-digestion of food waste and sludge in batch fermentation by anaerobic mixed cultures were optimized using Response Surface Methodology with Central Composite Design. Investigated parameters included C/N ratio, inoculums concentration, Na<SUB>2</SUB>HPO<SUB>4</SUB> concentration and Endo nutrient addition. The experiments were conducted in 120mL serum bottles with a working volume of 70mL. Results revealed that the optimum conditions were a C/N ratio of 33.14, inoculums concentration of 2.70g-VSS/L, Na<SUB>2</SUB>HPO<SUB>4</SUB> concentration of 6.27g/L and Endo nutrient addition of 7.51mL/L. Under the optimal conditions, a maximum hydrogen yield (HY) of 102.63mLH<SUB>2</SUB>/g-VS<SUB>added</SUB> and specific hydrogen production rate (SHPR) of 59.62mLH<SUB>2</SUB>/g-VSSh were obtained. C/N ratio and inoculums concentration showed the greatest individual and interactive effects on HY and SHPR (P<0.05). Endo nutrient addition also had an individual effect on SHPR (P=0.0124). The confirmation experiment under optimal condition showed an HY and SHPR of 101.14mLH<SUB>2</SUB>/g-VS<SUB>added</SUB> and 59.43mLH<SUB>2</SUB>/g-VSSh, respectively. This was only 1.01% and 1.00%, respectively, different from the predicted values.