| 摘要 |
PURPOSE:To facilitate the separation of the impurity by adding water into the tower top when the impurity of fermented alcohol is conducted the countercurrent extraction by using propane, propylene, n-butane or i-butane as the solvent. CONSTITUTION:A mixture of water/ethanol/impurity as the raw material is supplied through a raw material supply line 2 at the middle of a countercurrent extraction tower 1, water is supplied from a water supply line 3 at the upper part of the extraction tower 1 and, on the other hand, the extraction solvent is supplied through a liquid solvent supply line 4 at the lower part of the countercurrent extraction tower 1 and while the extraction solvent is kept in a liquid state, the countercurrent extraction operation is carried out. The impurity is selectively extracted with the solvent and is taken out from a solvent take-out line 6 as a solvent phase not incorporating ethanol together with the solvent. From a raffinate take-out line 5 on the tower top, a mixture of water/ethanol separated the impurity is taken out. This process can easily separate ethanol and prevent the loss of ethanol. |
