| 摘要 |
PROBLEM TO BE SOLVED: To provide such a method for cleaning a biodiesel fuel that, environmental burden stemming from effluent after cleaning can be reduced by decreasing water in the cleaning and reusing such water, the refining process is simple with no need of any drying step and the production cost is low, thus a high-purity fatty acid methyl ester or fatty acid ethyl ester usable as biodiesel fuel can be obtained, and concurrently, alcohol fractions are recovered and reused, and the amount of soap to be disposed of is decreased by suppressing saponification reaction. SOLUTION: The method for cleaning a biodiesel fuel by an alkali-catalyzing technique comprises the following process: misty water microparticles generated by a humidifier are gently allowed to fall spontaneously into a cleaning tank, and a fatty acid methyl ester or fatty acid ethyl ester is refined by removing alkali ions, glycerol and free fatty acids through suppressing saponification reaction. Surplus water in the lower layer in the cleaning tank is distilled to recover alcohol fractions. The distillation is continued, and the resultant distilled water is fed to the humidifier. Hydrophobic components (the objective biodiesel fuel, free fatty acids, etc.) contained in the surplus water in the lower layer in the cleaning tank are then separated and recovered. COPYRIGHT: (C)2009,JPO&INPIT
|
