Defoamers: linking fundamentals to formulations

Abstract Antifoam (defoamer) chemicals are a crucial part of many industrial processes. Reviewed are the types of defoamers and their mode of operation. Emphasized are the properties and location of the hydrophobic particles which are the active foam breaking agents. The roles of surfactants in spreading, defoamer emulsification and hydrophobic particle orientation are also discussed. Finally, a simple model is described which simulates foam growth as functions of defoamer concentration, air hold‐up, reactor volume and air flow rate. Copyright © 2003 Society of Chemical Industry