Process Systems Engineering for Biofuels Development

11Thermochemical Processes for the Transformation of Biomass into Biofuels

Carlos J. Durán‐Valle

Departamento de Química Orgánica e Inorgánica, IACYS, Universidad de Extremadura, 06006 Badajoz, Spain

11.1 Introduction

When plants grow, all carbon in the biomass comes from the atmosphere. When plants are burned, all carbon is liberated, giving a zero net carbon footprint. However, if fossil fuels are used, it causes a flow of carbon from the soil into the atmosphere, creating a greenhouse effect that produces global warming. Global warming coupled with declining fossil fuel reserves has attracted a great deal of attention for sustainable processes using renewable resources. Among them, obtaining fuels from biomass stands out.

There are two main routes for obtaining biofuels from biomass: biological and thermochemical (Damartzis and Zabaniotou 2011). Other methods such as direct solvent extraction or chemical hydrolysis are still under investigation or are inefficient in most cases. Depending on the raw material and the desired target, some methods may be preferable to others. Figure 11.1 shows a classification of the main methods for obtaining biofuels from biomass and the main products obtained with each method.

Figure 11.1 Processes for the transformation of biomass into biofuels.

Thermochemical processes for the transformation of biomass are a set of methods characterized ...