| 摘要 |
PURPOSE:To obtain absolute ethanol from an ethanol raw material with saved energy, by using combination of a distillation apparatus consisting of a concentration column, azeotropic distillation column and solvent recovery column with a decarbonation apparatus to remove previously gaseous carbon dioxide in the raw material. CONSTITUTION:An ethanol raw material 1 containing CO2 is fed to a deaeration column (A) decompressed by a vacuum generating device (H), decardonated and fed to a concentration column (B) to prevent trouble due to accumulation of CO2. The concentration column (B) and an azeotropic distillation column (C) are used as pressurized distillation columns, and overhead vapors 4 and 8 of both columns (B) and (C) are compressed by compressors (G1) and (G2) to heat bottoms 6 are 11 of the respective columns (B) and (C) with the compressed gases 4' and 8'. One condensed liquid 4' is partially fed to the column (C), and the other is returned to the column (B). The other condensed liquid 9 is separated into two layers in a decanter (F), and the upper layer is returned to the column (C). The lower layer is fed to a solvent recovery column (D). The overhead vapor 14 of the column (D) is cooled, condensed, and partially reluxed to the top of the column (D). The other is returned to the decanter (F) respectively, and water is taken out of the bottom 17 of the column (D) to give the aimed absolute ethanol advantageously from the bottom 7 of the column (B). |
