This device is suitable for the recovery of dilute alcohol in industries such as pharmaceuticals, food, light industry, and chemical engineering. It is also applicable to the distillation of other solvents such as methanol. This device can distill dilute alcohol at around 30 ℃ to alcohol at 90 ℃ -95 ℃ according to user requirements. The higher the required alcohol content of the finished product, the higher the reflux ratio can be increased, but the output will correspondingly decrease. W-type can also be used for distillation of methanol and other substances. W-type is intermittent, ZW type is continuous.