초록
<P><B>Highlights</B></P><P>► Optical fiber can contact with light-demanding microorganisms to achieve high light transmission efficiency. ► Biofilm has the advantages of low mass transfer resistance, easy light penetration and high operation stability. ► The rough surfaces improve hydrogen production performance because the increase of the attachment site. ► Investigation was carried out for the feasibility and effectiveness of the application of bioreactor with rough surface.</P> <P><B>Abstract</B></P><P>In this study, a biofilm photobioreactor with optical fibers that have additional rough surface (OFBP-R) was developed and it was shown that additional rough surface greatly enhanced the biofilm formation and thus increased the cell concentration, leading to an improvement in the hydrogen production performance. The effects of operational conditions, including the influent substrate concentration, flow rate, temperature and influent medium pH, on the performance of OFBP-R were also investigated. The experimental results showed that the optimum operational conditions for hydrogen production were: the influent substrate concentration 60mM, flow rate 30mL/h, temperature 30°C and influent medium pH 7. Under the optimal operation conditions discovered in this work, the OFBP-R yielded fairly good and stable long-term performance with hydrogen production rate of 1.75mmol/L/h, light conversion efficiency of 9.3% and substrate degradation efficiency of 75%.</P>