Abstract
Microalgae are microorganisms of great relevance towards sustainable development, due to their elevated growth rate without the requirement of fertile lands; they can also absorb carbon dioxide and other pollutants during their cultivation. Moreover, all the fractions of microalgae can be transformed to produce chemical compounds, biofuels, as well as other value-added products. In the cultivation of microalgae, the bioreactor design is a key element. In this case, the bioreactor must enable the reception of the highest values of photosynthetically active radiation and it has to promote good availability of nutrients for allowing good microalgae culture; also, this system must reduce both energy and water flow requirements in order to ensure the positive energetic balance and reduce the operating costs. In this context, process intensification is a powerful tool that allows improving the design of the bioreactors since both mass and heat transfer rates are increased; in some cases, it is possible to combine two individual unit operations or reduce the equipment size. Therefore, in this chapter, a review of the available literature regarding the intensification of bioreactors for microalgae cultivation will be presented. The outline of the chapter includes information about the most relevant microalgae species and their bioproducts, as also the conventional bioreactors used for their cultivation. Later, the intensification strategies reported in the literature will be presented, based on which the future trends will be discussed.
