(521a) Characterization of Bio-Oil, Bio-Char from Biomass Fast Pyrolysis and Bio-Char Application into Soil

Fast pyrolysis of biomass was carried out in a fluidized bed reactor. Three kinds of products including bio-oil, biochar and non-condensible gases were obtained. Characterization of bio-oil, bio-char from biomass fast pyrolysis and bio-char application into soil were investigated. Bio-oil is a clean, cost effective liquid alternative to replace fossil fuel for ‘green power’ generation, transportation and district heating. However, the properties and chemical composition of bio-oil are distinct from petroleum fuel. In general, due to its relatively high water and oxygen content, bio-oil is acidic and not stable when heating. Components of bio-oil from fast pyrolysis of rice hull and their relative mass contents  were detected by GC–MS method. It is shown that fast pyrolysis is a complex process. 112 types of chemical compounds were detected. The ash and fixed carbon content increased and volatile component content decreased for all the three feedstock including elm wood, pine wood and rice hull after pyrolysis. The rice hull biochar had the highest ash content and the lowest fixed carbon and volatile component, which was 50.94%, 33.35% and 13.11%, respectively. The pH value of biochar was from neutral to alkalinity. Of the three kinds of biochar, the pH of pin wood biochar(9.06) was higher than that of rice hull biochar(7.49) and elm wood biochar(6.35). Therefore, rice hull biochar and pine wood biochar could be applied to acid soil improvement. Rice hull biochar had the highest specific surface area (BET) (78.15 m3/g) and apparent densities (418.3 kg/m3), and SEM analysis also confirmed that rice hull biochar had the most micropores. Fourier transform-infrared (FT-IR) demonstrated that the functional groups of three kinds of feedstock were similar, and also similar of three biochar except that rice hull biochar had extra arene functional groups. Results of two-month soil experiment showed that rice hull biochar(4%) could increase soil nutrition including N, K, Mg and Mn, especially for K content of soil which increased from 0.055 to 0.417mg/kg. The soil carbon increased 1.69 times, and the pH value increased from 3.33 to 3.62, but there was no significant effect to phosphorus. The most important thing is that rice hull biochar reduced the Pb and Al availability to some extent, so it could be used to improve the soil quality that was contaminated by heavy metals. Although application biochar into soil has many advantages, a long-term field experiment and the effect of production of biochar on environment need to be estimated before application of biochar in a large scale.