UASB reactor bio-hydrogen production characteristics of stable operation

摘要

This study chose brown sugar as substrate for bio-hydrogen production using an up flow anaerobic sludge bed (UASB) to prove the feasibility of biological hydrogen and the characteristics during the phases of steady operation.In this paper,brown sugar was used as the substrate to be the artificial wastewater,Temperature was controlled at about (35 ± 1) °C HRT was 8 h.During the whole operation,ORP stably remained at the range of-380 mV～-440 mV.COD removal rate was above 28％.Although,pH value in feeding box varied a lot,the pH value in effluent was always stably maintained at the range of 4.5～5.0.Fermentative gas production kept significant increasing,the maximum value of which is 27.040 L/d while the hydrogen content is about 50％ at the same time.Terminal liquid production was consisting of ethanol,acetic acid,butyric acid and propionic acid.As the expected aimed production,ethanol acid and acetic acid kept increasing,the proportion of which was large and stably maintaining at the range of 80％～85％.Furthermore,the content of ethanol in terminal liquid production was significantly higher than acetic acid,propionic acid and butyric acid,which indicated that the system,in UASB reactor,successfully formed ethanol-type fermentation.