亚心形四爿藻培养和产氢过程一体化平板光生物反应系统

Integrated Cultivation and Photohydrogen Production of Tetraselmis Subcordiformis in a Flat-plate Photobioreactor System

利用整合了燃料电池的平板光生物反应器,探讨了将亚心型四爿藻高密度培养和产氢两段工艺一体化集成的可行性.在培养阶段通入体积分数为2%～5%的CO2可使藻细胞迅速增殖,9 d内即可达到产氢要求的生物量（8.5×10^6cell/mL）.通过叶绿素荧光参数分析,选择2%的CO2培养的藻进行后续的产氢实验.结果表明,PSⅡ活性和光合电子传递速率均随时间的推移而逐渐下降.通过对产氢动力学曲线的分析,计算出最大产氢速率为1.1 mL/（h·L）,持续产氢时间为60 h.

This paper aimed to develop an integrated processes of microalgal cultivation and hydrogen photoproduction in a fiat-plate photobioreactor system combined with alkaline fuel cell. The optimal high cell density of 8.5 × 10^6 cell/mL was achieved on 9 d when the cultivation of Tetraselmis subcordiformis was supplemented with CO2 of 2%-5% （volume fraction） in the flat-plate photobioreactor. When the bioreactor system was switched to the hydrogen production condition, hydrogen evolution was induced by the addition of carbonylcyanide （m-chlorophenylhydrazone, CCCP） and anaerobic condition, with a maximum hydrogen production rate of 1.1 mL/（ h · L） for 60 h. The kinetics analysis of algal chlorophyll fluorescence was carried out to identify the limiting factors in both algal growth and hydrogen production at 2% CO2 supplementation. At hydrogen production phase, algal PS 11 activity and relative electron transfer rate （rETR） decreased with the increase of time, which caused the decline and eventual stop in hydrogen production. To sustain the hydrogen production, PS Ⅱ activity and rETR must be maintained. The results demonstrate the feasibility of process integration of algal cultivation and hydrogen production in one single system, which will significantly improve the process economies.