𝔖 Bobbio Scriptorium
✦   LIBER   ✦

Microalgae cultivation in air-lift reactors: Modeling biomass yield and growth rate as a function of mixing frequency

✍ Scribed by Maria J. Barbosa; Marcel Janssen; Nienke Ham; Johannes Tramper; René H. Wijffels


Publisher
John Wiley and Sons
Year
2003
Tongue
English
Weight
310 KB
Volume
82
Category
Article
ISSN
0006-3592

No coin nor oath required. For personal study only.

✦ Synopsis


Abstract

The slow development of microalgal biotechnology stems from the failure in the design of large‐scale photobioreactors where light energy is efficiently utilized. Due to the light gradient inside the reactor and depending on the mixing properties, algae are subjected to certain light/dark cycles where the light period is characterized by a light gradient. These light/dark cycles will determine productivity and biomass yield on light energy. Air‐lift reactors can be used for microalgae cultivation and medium‐frequency light/dark cycles will be found in these systems. Light/dark cycles are associated with two basic parameters: first, the light fraction, i.e., the ratio between the light period and the cycle time and second, the frequency of the light/dark cycle. In the present work, light/dark cycles found in air‐lift reactors were simulated taking into account the light gradient during the light period. The effect of medium‐frequency cycle time (10–100 s) and light fraction (0.1–1) on growth rate and biomass yield on light energy of the microalgae Dunaliella tertiolecta was studied. The biomass yield and growth rates were mainly affected by the light fraction, while cycle time had little influence. Response surface methodology was used and a statistical model describing the effect of light fraction and cycle time on growth rate and biomass yield on light energy was developed. The use of the model as a reactor design criterion is discussed. © 2003 Wiley Periodicals, Inc. Biotechnol Bioeng 82: 170–179, 2003.