Stripping columns are used to remove unwanted materials from process streams. The air stripping column shown below is used to remove ammonia from water and wastewater feedstreams. This section describes various types of air stripping columns as well as steam strippers.


A membrane is a thin barrier that permits the transport of certain species across it from one fluid to another. Membranes can be classified by the operating driving force for transport.


Liquid-liquid extraction has only become popular as a separations technique in the past thirty years. In this time, liquid-liquid extractors have become the separation equipment of choice for selected processes.


Crystallizers are used in industry to achieve liquid-solid separation. They are an important piece of chemical processing equipment because they are capable of generating high purity products with a relatively low energy input.