Photobioreactor predictive models

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... 

Thus, the construction of predictive models of photobioreactors requires careful formulation of radiative transfer within the reaction volume, in order to obtain the radiation field (cf step 1 in the earlier procedure). Such analysis is developed this chapter, starting in Section 2 with determination of the light scattering and absorption properties of photosynthetic-microorganism suspensions. Next, these properties are used in Section 3 for analysis of radiative transfer and in Section 4 for rigorous solution of the radiative transfer equation by the Monte Carlo method. Finally, the thermokinetic coupling between radiative transfer and photosynthesis is addressed in Section 5. It should be noted that Sections 2 and 4 mainly summarize works that have been already published elsewhere, whereas Sections 3 and 5 include extensive original work and results. 

Umitation by Hght (luminostat y = 1, or photo-limitation y < 1, see Comet, 2010) are presented in Table 2. They are compared with the predictive model calculations presented in this chapter, where the radiative transfer equation was solved using the one-dimensional two-flux approximation for all the simple geometric stmctures of photobioreactors except for reactor PBR 2 (as indicated in Table 2), for which we used the three-dimensional finite element method developed by Comet et al. (1994). As shown in the table, the mean deviation between the experimental results and the model calculation is less than 5% (ie, within the range of the experimental standard deviation), thus confirming the ability of the proposed predictive approach to quantify photobioreactor performance under many conditions of operation. 

Pottier L, Pmvost J, DeremetzJ, CometJF, LegrandJ, Dussap CG A fuUy predictive model for one-dimensional light attenuation by chlamydomonas reinhardtii in a torus photobioreactor, Biotechnol Bioeng 91(5) 569—582, 2005. 

In the simplified model approach to predict photobioreactor productivity adopted in this chapter it was assumed that microalgae immediately respond... 

D Aquino CA, BalmantW, Ribeiro RLL, Munaro M, Vargas JVC, Amico SC. A simplified mathematical model to predict PVC photodegradation in photobioreactors. Polym Test 2012 31 (5) 638-644. 

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