Photobioreactor light

Photobioreactors Light-controlled chambers used to grow microalgae in mass culture. 

KEYWORDS Hydrogen production, photosynthetic bacteria, photobioreactor, light energy conversion... 

Grima ME, Fernandez AFG, Camacho GF, Chisti Y Photobioreactors light regime, mass transfer, and sc2lenp,J Biotechnol 70 231-247, 1999. 

The rate of H2 production by one unit of photobioreactor s volume is not useful for estimation of strain capabilities or for measurements of efficiency of light energy conversion. However, it is useful unit of measurements for optimization of hydrogen production by particular photobioreactor. From practical point of view it does not matter how much cells are in the photobioreactor or how much hydrogen is produced by one unit of illuminated surface. The rate of hydrogen production by the whole photobioreactor is of first importance. For a comparison of different photobioreactors it is better to express rate of hydrogen photoproduction per unit of its volume. So, it is practical unit for estimation of actual hydrogen photoproduction. 

Many different types of photobioreactors for suspension cultures are described in literature. The photobioreactor construction should solve the main problem an application of uniform light intensity to the culture. The detail description of photobioreactors is not a topic of present mini-review. For reference last reviews of photobioreactors are available [Tsygankov, 2001 Akkerman et al., 2002],... 

El-Shishtawy R.M.A., S. Kawasaki, M. Morimoto (1997) Biological ff2 production using a novel light-induced and diffused photobioreactor. Biotechnol. Techn., 11 403-409... 

A. A. Tsygankov, T. Laurinavichene, I. Gogotov, Y. Asada, J. Miyake (1996) Switching over from light limitation to ammonium limitation of chemostat cultures of Rhodobacter capsulatus grown in different types of photobioreactors. J. Marine Biotechnol., 4 43-46... 

In summary, an optimal H2-photoproducing biological system would have to be able to function at high rates and with about 10% solar light conversion efficiency in an aerobic atmosphere, simultaneously evolving H2 and O2 gases at a ratio of 2 1. Materials and gas separation issues, as well as photobioreactor designs to address these, will be discussed in section 5.3. 

Sun light should be provided homogeneously at appropriate intensity inside of photobioreactors, which seems a key factor for improvement of efficiency. 

Incident light intensity measured at the surface of photobioreactor. 

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