Laboratory distillation set-up: 1: Heat source 2: Still pot 3: Still head 4: Thermometer/Boiling point temperature 5: Condenser 6: Cooling water in 7: Cooling water out 8: Distillate/receiving flask 9: Vacuum/gas inlet 10: Still receiver 11: Heat control 12: Stirrer speed control 13: Stirrer/heat plate 14: Heating (Oil/sand) bath 15: Stiring means e.g. magnetic follower (shown), anti-bumping granules or mechanical stirrer 16: Cooling bath.

Distillation is a method of separating chemical substances based on differences in their volatilities in a boiling liquid mixture. Distillation usually forms part of a larger chemical process, and is thus referred to as a unit operation.

Commercially, distillation has a number of uses. It is used to separate crude oil into more fractions for specific uses such as transport, power generation and heating. Water is distilled to remove impurities, such as salt from sea water. Air is distilled to separate its components - notably oxygen, nitrogen and argon - for industrial use. Distillation of fermented solutions has been used since ancient times to produce distilled beverages with a higher alcohol content.

实验室蒸馏装置：1：热源 2：蒸馏瓶 3：蒸馏瓶顶盖 4：温度计/沸点温度5：冷凝器 6：冷却水进口 7：冷却水出口 8：蒸馏物/接收烧瓶 9：真空/气体入口 10：蒸馏接收器 11：加热控制器 12：搅拌器速度控制器 13：搅拌器/加热板 14：热浴(油或沙) 15：搅拌方法，磁力搅拌、防爆沸石搅拌或机械搅拌 16：冷浴蒸馏是一种根据沸腾液体混合物挥发度差而分离化学物质的方法。蒸馏通常构成一个大的化学工艺的一部分，因而，是一个单元过程。

蒸馏在商业上有一些使用价值，被用于将原油分离为更多的具有特殊用途(如，交通、动力及加热)的组分。把水进行蒸馏以除去杂质，如从海水中除去盐。为了工业用途，进行空气蒸馏以分离其组分，特别 是氧气、氮气和氩气。古代，人们蒸馏发酵液以产生乙醇含量较高的蒸馏酒。