Photobioreactor solar

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. 

A key property of potential construction materials for solar H2 photobioreactors is the rate of H2 and O2 permeation through the materials. Data on the perme-... 

Figure 9 A schematic diagram of the system for solar light collection and transmission into the photobioreactor.

Figure 10 A schematic diagram of integrated solar and artificial light for internal illumination of a stirred tank photobioreactor.

Ogbonna J. C., Soejima T. and Tanaka, H. (1999). An integrated solar and artificial light system for internal illumination of photobioreactors. J. Biotechnol. 70,289-297. 

In conelusion, green algae with a truneated Chi antenna size are indispensable in efforts to substantially inerease solar eonversion efifieieneies and the yield of biomass and H2 production in photobioreactors under mass eulture conditions. 

Photobioreactor engineering addresses optimization of the volumetric rate of biomass production, the surface rate of biomass production (with respect to the solar-energy collecting surface), and thermodynamic efficiency of the process as well as biomass composition (ie, the biomass quality). Hereafter, we mainly focus on construction of a predictive model for the volumetric rate (eg, expressed in kg, or moles of dry biomass per second and per m of the reaction volume). This is the main difficulty with assessing performance of a photobioreactor because most of the other parameters of interest can be deduced only from the value of < >, in a... 

Initially, we will focus on the mesoscopic description associated with the radiative transfer equation. Then, we will introduce the single-scattering approximation and two macroscopic approximations the PI approximation and two-flux approximation. AH of these discussions are based on the configuration shown in Fig. 6. Collimated emission and Lambertian emission wiU also be considered in the discussion later they correspond to the direct component and the diffuse component of solar radiation, respectively. Throughout our study, the biomass concentration Cx is homogeneous in the reaction volume V (assumption of perfect mixing), and the emission phenomena in V are negligible. The concentration Cx is selected close to the optimum for the operation of the photobioreactor the local photon absorption rate. 4 at the rear of the photobioreactor is close to the compensation point A.C (see Section 5 and chapter Industrial Photobioreactors and Scale-up Concepts by Pruvost et al.). 

In Fig. 24, the irradiance field obtained with the two-flux approximation for fi —> 00 is compared with the Monte Carlo reference solution in the case of collimated solar-light incidence. The two-flux approximation wiU be used in Section 5.6 to analyze the coupling between radiative transfer and photosynthesis thermokinetics in photobioreactors with simple geometric structure. 

It is also important to note that due to the linearity of the radiative transfer equation, the solutions for configurations illuminated on both sides (or for mixtures of collimated and difiuse illumination) are obtained simply by adding up the solutions obtained in this section. For example, for incident solar radiation with direct and diffuse components, the radiation field can be obtained by adding up solutions 2 and 3. For a photobioreactor illuminated... 

Figure 26 (A) A 25 L prototype of the solar volumetrically illuminated photobioreactor DiCoFluV (Cornet, 2010). (B) EDStar geometric structure both the reactor 1Z) and the 979 light-diffusing optical fibers [T) are cylinders 1 m high the reactor s diameter is 16.5 cm, the distance between two fiber axes is djr = 4.8 mm, and the fiber radius is ryr = 1.2 mm.Tl and T are diffuse-reflective with uniform reflectivity p and pT, respectively.. is Lambertian emitting with the uniform surface flux density qn,v (Q Two-dimensional hexagonal lattice fiber arrangement an optical-path example in the culture medium V.

Acien Fernandez FG, Garcia Camacho F, Sanchez Perez JA, Fernandez Sevilla JM, Mohna Grima E A model for light distribution and average solar irradiance inside outdoor tubular photobioreactors for the microalgal mass culture, Biotedinol Bioeng 55(5) 701—714, 1997. 

DiCoFluV solar photobioreactor with Fresnel lenses for sun capture and lateral diffusing optical fibers inside the reactor (Institut Pascal, Clermont-Fd, France)... 

Goetz V, Le Borgne F, PruvostJ, Plantard G, LegrandJ A generic temperature model for solar photobioreactors, Chem EngJ 175 443-449, 2011. 

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