Influence of Reaction Temperature, Pretreatment, and a Char Removal System on the Production of Bio-oil from Rice Straw by Fast Pyrolysis, Using a Fluidized Bed

Rice straw is one of the main renewable energy sources in Korea, and bio-oil from rice straw is produced using a bench-scale plant that is equipped mainly with a fluidized bed and a char removal system. We investigated how the reaction temperature affected the production of bio-oil and the efficiency of a char removal system. To elucidate how the temperature was dependent on the production of bio-oil, experiments were conducted between 400 °C and 600 °C at a feed rate of ∼1 kg/h. The mass balance was established in each experiment, and the produced gas and oil were analyzed with the aid of gas chromatography and a gas chromatography−mass spectroscopy (GC−MS) system. The effect of pretreating rice straw was also investigated by comparing the yield of bio-oil and the content of alkali metals in the bio-oil from the experiments on unwashed rice straw with the corresponding values of washed rice straw. The char removal system is composed of a cyclone and a hot filter. After every experiment, we examined the p...