内容提要: |
Previous studies showed that alkali pretreatment prior to anaerobic digestion can increase the digestibility and methane yield of lignocellulosic biomass, but the development of alkali pretreatment was limited by high cost of alkali consumption. For this , black liquor from paper industry was used to pretreat corn stover at different alkalinity (3, 6, 12, 24 g NaOH/L) for different time periods (3, 6, 12, 24, 48h). The highest methane production of anaerobic digestion ( 260.51 mL/g VS) of corn stover was achieved by the treatment with 12g NaOH/L alkalinity BL for 24h, which was 59.10% higher than untreated corn stover (163.74 mL/g VS) due to the chemical and physical changes of the substrates during the pretreatment process. Organic components in the black liquor attributed to the methane production of co-digetion for 171.73 ml/g VS. Effect of black liquor pretreatment on the stability of anaerobic digestion was investigated in semi-continuous mode, the results show that black liqour increased the buffering capacity of the digester to maintain suitable pH and total VFA/alkalinity ratio, thus leading to higher biogas production compared with no black liqour used. On the whole, the results showed that black liquor pretreatment followed by the whole slurry anaerobic co-digestionwas feasible and could contribute to application value for anaerobic digestion industry while providing an effective way for the treatment of BL wastewater. |