环流型光纤生物膜制氢反应器的底物传输与降解特性

Performance of Substrate Transport and Bio-degradation within Annular Optical-fiber-illuminating Biofilm Reactor during Continuous Photo-H_2 Production

以连续流产氢为目标,采用高透光性弥散光纤作为导光介质和光合细菌吸附成膜的载体,构造了环流型光纤生物膜制氢反应器。在实验研究的基础上,根据传质原理和Monod生化反应动力学建立了描述连续流反应器中底物传输和降解的二维数学模型。以强化底物传输和提高底物降解效率为目标,对反应器的实际操作参数进行了优化。研究结果表明,反应器的底物传输特性对反应器的底物降解效率有显著影响。反应器的底物降解效率随进口底物质量浓度的增加呈现先增大后减小的趋势。反应器的底物降解效率随流速的增加呈现逐渐减小的趋势。当反应器的进口底物质量浓度为10 g/L,流速为100 m L/h时,底物消耗速率最大,底物降解效率达到43.5%。合理地控制反应器中的底物传输使得生物膜区域具有适合的底物质量浓度分布,是维持反应器较高底物降解效率的有效途径。

An annular optical-fiber-illuminating biofilm reactor （AOFBR） was developed with photosynthetic bacteria （PSB） attached on the surface of side-glowing optical fiber for the formation of biofilm and continuous photo-hydrogen production. To enhance mass transport and improve substrate bio- degradation efficiency within AFOBR, a two-dimensional mass transfer model was proposed based on the theory of mass transfer and kinetics of bio-chemical reaction. Results on numerical investigation revealed that characters of mass transfer obviously affected biodegradation within AFOBR. With the increase of inlet substrate concentration, substrate degradation efficiency was increased at early stage but decreased later. While, with the increase of flow rate, substrate bio-degradation efficiency was always decreased. The maximum substrate bio-degradation of 43.5% was available with 10 g/L of inlet substrate concentration and 100 mL/h of flow rate. To regulate mass transfer and maintain appropriate substrate concentration within biofilm was proved to be the effect way to achieve higher substrate degradation efficiency within the bioreactor.