Separation operations achieve their objective by the creation of two or more coexisting zones which differ in temperaturepressure, compositionandor phase stateEach molecular species in the mixture to be separated reacts in a unique way to differing environments offered by these zonesConsequentlyas the system moves toward equilibriumeach establishes a different concentration in each zoneand this results in a separation between the species分离过程通过形成在温度、压力、组成和相态上有区别的两个或多个共存区来达到它的目的。每一种待分离的在混合物中的分子种类以一种独特的17方式与这些区域提供的不同的环境相互作用。结果是随着系统向平衡移动每个物质都在每个区域形成不同的浓度这样就可以使这些物质的到17分离。 The separation operation called distillation utilizes vapor and liquid phases at essentially the same temperature and pressure for the coexisting zonesVarious kinds of device such as dumped or ordered packings and plates or trays are used to bring the two phases into intimate contactTrays are stacked one above the other and enclosed in a cylindrical shell to form a columnPackings are also generally contained in a cylindrical shell between hold-down and support plates利用在共有区中拥有相同温度和压力的汽油和液相的分离操作叫做分离。不同种类的装置例如规整填料和乱堆整料和塔板或塔盘被用来使两相充分接触。塔盘是一个堆着一个排列的并且被装入到一个圆柱形的外壳中形成一个塔。填料通常也被装入一个在压具板和支撑板之间的圆柱形外壳中。
1 Continuous Distillation The feed materialwhich is to be separated into fractionsis introduced at one or more points along me column shellBecause of the difference in gravity between vapor and liquid phases, liquid runs down me columncascading from tray to traywhile vapor floats up the columncontacting liquid at each tray. 2
