Application of cassava harvest residues (Manihot esculenta Crantz) in biochemical and thermochemical conversion process for bioenergy purposes: A literature review

Bioenergy production from biomass and agricultural wastes has gained significant interest due to rising fossil fuel prices and their decrease in air pollutant emissions. This review paper evaluates the state-of-art for the several applications from cassava harvest residues and their use in bioenergy industry, using different thermochemical and biochemical processes. Regarding the great available literature for this biomass, several pretreatment techniques, including mechanical, chemical, biological, thermal, ultrasonic and wet explosion were observed. The use of cassava harvest residues for the biochemical pretreatments, for example, hydrolysis, fermentation and thermochemical processes, such as direct combustion, gasification, pyrolysis, fast pyrolysis and oxy-fuel combustion was also discussed. Therefore, studies are necessary in order to understand that the use of cassava residues in thermal processes can increase the viability of this feedstock for biofuels production and/or in power co-firing units. After extensive study, it was observed that informations are still lacking about the use of cassava harvest residues in other conversion processes, thus, new studies to discover more on the use of this biomass, in order to extend their application in the bioenergy market is encouraged. Key words: Biomass, cassava, harvest, processes, residues, biochemical, thermochemical.