Bio-oil can be produced from the pyrolysis of wood. Pyrolysis is defined as hydrothermal liquefaction that takes place in an oxygen-deficient environment. The pyrolysis process generates three fractions namely liquid (condensibles), solid (char), and off-gas (non-condensibles). Often these non-condensibles are hard to account for when completing mass balance closures around the reactor. The pyrolysis liquid is generally termed as bio-oil. While the generation of bio-oil is still in its developmental phase, it is anticipated that this material will have many uses. One of the potential uses of bio-oil is as a fuel. Unfortunately, bio-oil is relatively unstable at ambient temperatures during prolonged storage periods. Because of this unstable behavior, bio-oil presents significant challenges towards its utilization as a potential fuel. A study has been undertaken by the researchers at the Chemical Engineering Department-Mississippi State University to develop cost-effective technologies to address this problem of instability. This study focuses on utilizing a small-scale auger reactor to produce bio-oils from different feedstocks at different reactor conditions. Pellets manufactured from pinewood and oak wood were utilized during this study. The main operating variables considered during the pyrolysis studies were feed rate, pyrolysis temperature, vapor residence time, and auger speed. The feed rate selected was between 0.5 and 1.0 kg/hr while the reactor itself was operated in a semi-batch mode. The pyrolysis temperatures of 400degC and 450degC were employed through out this study. A multi-stage condenser was utilized to collect the quenched bio-oils. Bio-oils were mainly collected as aqueous rich and hydrocarbon rich fractions from the condenser at different condensation temperatures.
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