Pyrolysis of torrefied Phragmites australis from atmospheric and gas-pressurized torrefaction: Pyrolysis kinetic and product analysis

摘要

Herein, the atmospheric torrefaction (AT) and the gas-pressurized torrefaction (PT) were compared as pre-treatment processes for pyrolysis of Phragmites australis (PAS) to scrutinize the influences of the torrefaction method on the physicochemical properties and pyrolysis kinetics of torrefied PAS (TPAS), and the features of bio-oils and biochars derived from TPAS. The experimental results showed that the pyrolysis stability level of PAS increased after torrefaction. The PT bio-oils contained more complex organic compounds than the AT bio-oils, indicating that PT could produce more valuable bio-oils than AT by pyrolysis of TPAS. The AT biochars had larger specific surface areas, smaller pore diameters and better adsorption capacity than the PT biochars, indi-cating that AT was more effective to produce better biochars from TPAS than PT. This study compared AT and PT as pretreatment processes for pyrolysis to investigate their effects on the properties of the produced bio-oils and biochars. These results will provide a theoretical basis for developing novel applications of torrefaction and pyrolysis of wetland plants.