title: Improving CO2 fixation efficiency by optimizing Chlorella PY-ZU1 culture conditions in sequential bioreactors.
abstract: To fix CO2 emissions efficiently from flue gas of coal-fired power plants, the culture medium, light intensity and bioreactors were comprehensively optimized in the process of CO2 fixation by Chlorella PY-ZU1. To make up for relative insufficiency of nutrients (except for the carbon source) resulting from continuous bubbling of 15% CO2, three chemicals were added into the culture to optimize the molar ratios of nitrogen to carbon, phosphorus to carbon, and magnesium to carbon in culture from 0.17 to 0.69, from 0.093 to 0.096, and from 0.018 to 0.030, respectively. Such adjustments led to a 1.25-fold increase in biomass (from 2.41 to 5.42 g L(-1)). By enhancing light intensity from 4500 to 6000 lux, the peak growth rate of Chlorella PY-ZU1 increased by 99% and reached to 0.95 g L(-1) day(-1). Use of a multi-stage sequential bioreactor notably improved the peak CO2 fixation efficiency to 85.6%.
authors.affiliation: State Key Laboratory of Clean Energy Utilization, Zhejiang University, Hangzhou 310027, China. juncheng@zju.edu.cn
authors.forename: Jun
authors.initials: J
authors.lastname: Cheng
authors.forename: Yun
authors.initials: Y
authors.lastname: Huang
authors.forename: Jia
authors.initials: J
authors.lastname: Feng
authors.forename: Jing
authors.initials: J
authors.lastname: Sun
authors.forename: Junhu
authors.initials: J
authors.lastname: Zhou
authors.forename: Kefa
authors.initials: K
authors.lastname: Cen
mesh_terms: D018533:Biomass; D019149:Bioreactors; D002245:Carbon Dioxide / Q000378:metabolism* / Q000494:pharmacology; D018929:Cell Culture Techniques / Q000295:instrumentation* / Q000379:methods*; D002708:Chlorella / Q000187:drug effects / Q000254:growth & development* / Q000378:metabolism* / Q000528:radiation effects; D002734:Chlorophyll / Q000378:metabolism; D003470:Culture Media / Q000494:pharmacology; D008027:Light; D008274:Magnesium / Q000494:pharmacology; D009566:Nitrates / Q000494:pharmacology; D010710:Phosphates / Q000494:pharmacology; D013997:Time Factors
chemical_list: D003470:Culture Media; D009566:Nitrates; D010710:Phosphates; D002734:Chlorophyll; D002245:Carbon Dioxide; D008274:Magnesium
keywords: Bioreactors; CO(2) fixation; Culture optimization; Light intensity; Microalgae