Steam Stripping

Steam stripping, also known as steam distillation, is an economic method of cleaning up plant wastewater streams. It is a multistage continuous distillation process where steam is used as a stripping gas to remove hydrocarbons from dischargeable waste waters; all while meeting the latest EPA, PEG (Pharmaceutical Effluent Guidelines) and NESHAP regulations such as MACT, HON, and MON.

It is easy to strip VOC’s by this method if they have lower boiling points than water or have limited solubility in water. The concentrated organic product generated by the steam stripping operation is a distillate stream. It is not uncommon for this stream to be a mixture of many compounds. Furthermore, it is usually desirable to minimize the volume of this distillate because it is often sent off-site for disposal or incineration.

Typically, waste minimization is accomplished by first condensing and then decanting the overhead product from the column to separate water insoluble organics, with subsequent refluxing of the water phase from the decanter to the top of the stripping column. If the stripped organics are soluble in water, then it is typical to add several rectification stages and reflux to the stripping column to reduce the water content of the distillate. The distillate can be drawn off as a liquid product for recycle or disposal, or as a vapor product that is then fed to a thermal oxidizer.