Abstract:

To solve the problem of insufficient light supply within cell-immobilized bioreactor, a new type of annular fiber-illuminating biofilm reactor(AFIBR)was developed for photo-H₂ production by indigenous photosynthetic bacteria Rhodopseudomonas palustris CQK 01 using glucose as the sole carbon source. A side-glowing optical fiber(SOF)with desired surface light intensity and uniform light distribution was inserted into a sealed glass vessel as internal light source of AFIBR and photosynthetic bacterial cells were successfully attached onto the surface of SOF to form a steady biofilm within bioreactor at the start-up stage of bioreactor. A detail investigation of the continuous hydrogen production performance of AFIBR was then carried out under different light wavelength, light intensity, inlet substrate concentration and flow rate. The results showed that AFIBR exhibited excellent performance on both hydrogen production and light energy conversion. A high hydrogen production rate of 0. 83 mmol·（g cell）^-1·h^-1 and excellent light conversion efficiency of 47.9% were attained under the operational conditions of monochromatic light illumination at 530 nm, light intensity of 4.15 W·m^-2, inlet substrate concentration of 10 g·L^-1 and flow rate of 100 ml·h^-1. The results revealed also that proper emission spectrum of light source, even light intensity distribution within cell-immobilized zone within bioreactor and enhanced mass transfer operation were efficient measures to improve the performance of AFIBR. So, further research on photobiological reactor may be necessary for practical hydrogen production.

摘要：

采用使光合细菌生物膜直接附着生长在具有高导光性的弥散光纤表面的方法，构造了环流型光纤生物膜制氢反应器，用于解决目前固定化细胞连续流光生物制氢反应器研究中存在的难以同时实现细胞固定化和保持细胞固定化区域具有良好光分布性的问题。通过连续流产氢实验研究发现该反应器在以葡萄糖为有机底物，入射光波长为530 nm，弥散光纤表面光照强度为4.15 W·m^-2，进口底物浓度为10 g·L^-1，流速为100 ml·h^-1的条件下，反应器的光能转化效率和产氢速率得到显著提高，分别达到47.9%和0.83 mmol·(g dry cell)^-1·h^-1。实验结果表明，采用适合光合细菌产氢的入射波长，保持固定化细胞区域均匀的光强分布和强化传质的操作方法都有助于提高反应器的产氢性能。该研究可以为规模化光生物制氢反应器的探索提供一定参考。