Slow Pyrolysis of Bamboo Biomass: Analysis of Biochar Properties

Abstract

Due to the issue of deforestation and the pressure to avoid use of native forest resources for production of char, there is increasing requirement for the use of renewable materials and development of additional sustainable processes. Bamboo, a biomass that presents the property of fast growth, is an alternative to native or reforested wood. In this work the slow pyrolysis of a woody bamboo (species Dendrocalamus giganteus Munro) was studied, aiming the determination of biochar properties. The process was conducted in a fixed bed reactor at temperatures ranging from 300 to 600 °C and at a 10 °C/min heating rate. The thermal degradation behaviour of bamboo was investigated through thermogravimetric analysis (TGA/DTG). The bamboo biomass and the biochar were characterized by physical-chemical analysis in order to investigate the main changes caused by the pyrolysis process on biochar properties. The surface morphology of bamboo biomass and biochar was determined using scanning electron microscopy (SEM). Additionally, a discussion about the advantages and disadvantages of biochar production by slow pyrolysis is presented, taking into account the applied conventional methods in the process. Results revealed the advantage of pyrolysis process due to simultaneous biochar and bio-oil production. The bamboo biochar presents suitable properties for its use as energy source and for agricultural applications. Its high porosity and carbon content suggest its application as activated carbon after physical or chemical activation.