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Principle of distillation: The process of separating a liquid mixture into relatively pure components by subjecting it to multiple cycles of partial vaporization and partial condensation is known as distillation. A continuous distillation column can be considered as a series of simple distillation vessels connected together. Due to the different volatilities of the components in the feed liquid, with each distillation cycle in one of the vessels, the concentration of light components in the vapor increases; that is, yn+1 > yn > x (where y represents the composition of the gas phase and x represents that of the liquid phase). By increasing the number of distillation vessels, it is possible to obtain light components of sufficient purity, while the amount of light components remaining in the liquid at the bottom of the column gradually decreases, approaching zero. By stacking these distillation kettles and simplifying their structure, a distillation column is created. As the operating pressure in the distillation process increases, the boiling point of the liquid mixture rises accordingly; as a result, the condensation temperature of methanol at the top of the pressurized distillation column also increases. By utilizing the heat of condensation of the methanol product at the higher temperature at the top of the pressurized distillation column as a heat source for the reboiler in the atmospheric pressure distillation column, it is possible to reduce the steam consumption in methanol distillation. This process utilizes an ether removal tower, a pressurized distillation tower, and a atmospheric distillation tower to separate the light and heavy components in the crude alcohol, thereby obtaining pure methanol as the product.