In the fermentation mash, not containing alcohol, further contains dozens of other components of the substance with water, the content of these substances far exceeds the content of the alcohol, the alcohol content of the mature wake is only 7-11% (volume) around, including water, alcohols, aldehydes, acids, lipids impurities accounted for almost 90% pure alcohol, some method must be used to separate the alcohol from the mash. Production is the use of heating distillation approach, a variety of different boiling point, specific gravity, volatile substance is separated from the different devices out, to thereby obtain a higher purity of alcohol.

    Crude distillation tower works by preheating the fermented mash, enter the upper part of the crude distillation tower bottoms constantly pass into evenly heated steam, this time due to the heating of the role can be liquid alcohol in the mash into alcohol.gas while the other low-boiling and volatile impurities in the alcohol together into column of row aldehyde (can also directly enter the fractionator), and the bottom after the distillation of the spent grain is discharged outside the tower.

    Crude distillation tower is operating normally, the top temperature shall not be lower than 93 ℃, but also can not be too high, too high temperature of the top of the separation of non-profits, and the large amount of steam consumed. General control in the 95-96 ℃. Temperature is too low, and wake up in the alcohol does not completely evaporated, escape wine significantly increases. The boiling point of the pure alcohol is 78.3 ℃, but the boiling point of the water and other ingredients mixed with the mixed liquid is far more than 78.3 ℃, therefore, the crude distillation bottoms temperature control should not be less than 105 ℃, generally between 105 ℃ -109 ℃.Before preheating the matured mash into the crude distillation tower, reducing the temperature difference, is conducive to the stable operation of the crude distillation tower. General should mash the preheating temperature control between 60-70 ℃, some production units due to the impact of equipment performance, generally low 5-10 ℃.