论文部分内容阅读
Molasses wastewater was evaluated as substrate for biohydrogen production by anaerobic fermentation in a novel continuous mixed attached growth reactor (CMAGR) with aeration pretreated sludge attached onto granular activated carbon under continuous flow condition. It was indicated that the CMAGR system was operated at the conditions of influent COD of 2000~6000 mg/L, hydraulic retention time (HRT) of 6 h and temperature of 35 ?, when the pH value and oxidation-reduction potential (ORP) ranged from 4. 16 and -434 mV respectively, stable ethanol-type fermentation was formed with the sum of ethanol and acetate concentration ratio of 89. 3％ to the total liquid products after 40 days operation. The H2 content in biogas and chemical oxygen demand (COD) removal were estimated to be 46. 6％ and 13％, respectively. It was also investigated that the effects of organic loading rates (OLRs) on CMAGR hydrogen production system. It was found that hydrogen production yield increased from 3.72 mmol/hL to 12.51 mmol/hL as OLRs increased from 8 kg/m3d to 32 kg/m3d. The maximum hydrogen production rate of 12. 51 mmol/hL at a OLR of 32 kg/m3d and the maximum hydrogen yield by substrate consumed was 130. 57 mmol/mol happened at OLR of 16 kg/ m3d. Greater pHs appeared to be. favour to butyrate production and the maximum of 0. 51 mol/ mol was obtained at pH of 4. 14. However, ethanol/acetate ratio was greater than 1. 1 at pH fluctuated between 3. 4?. 6 and 4. 1?. 4 which indicated that these pHs were favour to ethanol type fermentation. Therefore, the continuous mixed attached growth reactor (CMAGR) could be a promising attached growth system for biohydrogen fermentation.