The effect on growth of Chlamydomonas reinhardtii of flue gas from a power plant based on waste combustion.
Flue gases from a power plant based on waste combustion were tested as a carbon dioxide (CO2) source for growing Chlamydomonas reinhardtii. To achieve recognition as an environmentally friendly hydrogen production method, waste gases should be used to grow this hydrogen-producing microalgae. The algae were grown in undiluted flue gas containing 11.4±0.2% CO2 by volume, in diluted flue gas containing 6.7±0.1% or 2.5±0.0% CO2, and in pure liquid CO2 at a concentration of 2.7±0.2%. The NOx concentration was 45±16 mg m(-3), the SO2 concentration was 36±19 mg m(-3), the HCl concentration 4.1±1.0 mg m(-3) and the O2 concentration 7.9±0.2% in the undiluted flue gas. Undiluted flue gas reduced the dry weight production by around 20-25% when grown at a photon flux density (PFD) of 300 μmol m(-2) s(-1) artificial light and at 24 or 33°C, compared with the other treatments. A less negative effect was found at the highest flue gas concentration when the algae were grown at 75 μmol m(-2) s(-1) PFD. Growing the algae outdoors at a day length of 12.5 h and a temperature of around 24°C, the dry weight production was higher (about 15%) in the 2.6% CO2 flue gas treatment compared with all other treatments. Reducing the light level by 30% through shading did not affect the dry weight production. Calculated on aerial basis the productivity reached approximately 70 g m(-2) day(-1) in the 300 μmol m(-2) s(-1) PFD treatment (corresponding to 25 mol m(-2) day(-1)) and approximately 17 g m(-2) day(-1) in the 75μmol m(-2) s(-1) PFD treatment (corresponding to 6.5 mol m(-2) day(-1)). The outdoor production reached around 14 g m(-2) day(-1). It was concluded that the negative effect of the undiluted flue gas was attributable to the high CO2 concentration and not to the other pollutants.
Department of Plant Science, The University of Life Sciences, Ås NO-1432, Norway.
Leiv M
LM
Mortensen
Department of Plant Science, The University of Life Sciences, Ås NO-1432, Norway.
Hans R
HR
Gislerød
Carbon dioxide concentration; Chlamydomonas reinhardtii; Flue gas; Photosynthetic active radiation