عنوان مقاله [English]
Background and objectives: Biomass is the only source of renewable carbon which can be converted to biofuels and added value products. Thermochemical processes such as fast pyrolysis can play an important role for production of biofuels, bio-chemicals and syngases from biorefinery technologies. With regards to this point that sugarcane wildly cultivate in south of Iran and its pith is an abundant resource of biomass from de-pithing process in pulp and paper and medium density fiberboard industries. The aim of this study is the comparison possibility use of bagasse and its pith for bio-oil production in pilot scale fluidized bed reactor and application development of biorefinery for bio-oil production and added-value products.
Material and methods: This research conducted on biofuel production in a pilot-scale reactor operating in a fluidized bed from bagasse and its pith. The components of bagasse are measured by proximate and ultimate analysis. The type and amount of heavy metals were used by applying an elemental analyzer. The thermal degradation characteristics were measured via TGA. Fast pyrolysis were performed at temperature of 470 °C, under screw feeder carrier the biomass in 90 g/h, inside pyrolyzer with nitrogen gas flow rate of 2 L/min.
The elemental analysis indicated that the pith of bagasse contains substantial amounts of extractives and inorganic matter (predominantly Ca, K and Mg). The results of TGA indicated that most of weight losses of bagasse and its pith are among 250 and 350 ˚C which associated with main degradation components (cellulose, hemicellulose and lignin). Under the mentioned conditions, the yields of 53.2%, 35.5% (w/w); 25, 37% (w/w); 21%, 27.5% (w/w) for bio-oil, bio-char, and syngases were obtained from bagasse and pith respectively. The fixed carbon on bagasse was higher than its pith which led to higher energy value, while pith of bagasse contributes the higher bio-char. The heating value of bio-oil from bagasse is 20.6 Mj/kg which higher than pith and most of lignocellulosic materials reported in literatures. The lower oxygen content of bagasse will reduce the cost of upgrading for converting to bio-diesel and other chemicals. The pyrolysis gases components are CO2, CO, CH4, H2 and other hydrocarbons like ethane, propane and ethylene. The carbon dioxide is the dominant gas among them. Bagasse produced more carbon dioxide than pith in fast pyrolysis process.
Conclusions: The pith showed higher thermal stability which result in more bio-char production, because of the higher lignin content of pith in the fast pyrolysis process. The fast pyrolysis bio-oil of bagasse not only showed the possibility renewable energy and chemicals, but also its syngases enable utilize as proper energy resource in industries.