首页 | 本学科首页   官方微博 | 高级检索  
     


Effect of light/dark cycles on wastewater treatments by microalgae
Authors:Kwangyong Lee  Choul-Gyun Lee
Affiliation:(1) Institute of Industrial Biotechnology, Department of Biological Engineering, Inha University, 402-751 Incheon, Korea
Abstract:Chlorella kessleri was cultivated in artificial wastewater using diurnal illumination of 12 h light/12 h dark (L/D) cycles. The inoculum density was 105 cells/mL and the irradiance in light cycle was 45 μmol m2 s−1 at the culture surface. As a control culture, another set of flasks was cultivated under continuous illumination. Regardless of the illumination scheme, the total organic carbon (TOC) and chemical oxygen demand (COD) was reduced below 20% of the initial concentration within a day. However, cell concentration under the L/D lighting scheme was lower than that under the continuous illuminating scheme. Thus the specific removal rate of organic carbon under L/D cycles was higher than that under continuous illumination. This result suggested thatC. kessleri grew chemoorganotrophically in the dark periods. After 3 days, nitrate was reduced to 136.5 and 154.1 mg NO3 -N/L from 168.1 mg NO3 -N/L under continuous illumination and under diurnal cycles, respectively. These results indicate nitrate removal efficiency under continuous light was better than that under diurnal cycles. High-density algal cultures using optimized photobioreactors with diurnal cycles will save energy and improve organic carbon sources removal.
Keywords:microalgae  nitrogen removal  diurnal cycle  wastewater
本文献已被 SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号