In concrete, producing an effective concrete-air content is a vital aspect. Though the air reduces the strength of the concrete, the air does add compressibility to the concrete. This makes the concrete more durable through temperature changes allowing the concrete bend and flex in very high or very low temperature conditions. There are situations when air is determined to be too excessive for those situations, and in that case, some specific phosphates are used to reduce the effects of the air on the concrete and bring the concrete back to its original strength. These products are called Defoamers. Defoamers are needed in the concrete when the thickening agents cause air to be trapped inside creating the foam. Common deformers used for this situation are Tributyl Phosphate (TBP). The thickening agent and defoamer (TBP) have a direct relationship in terms of usage (i.e. more thickening agent used the more defoamer that will be needed as well).
Phosphate defoamers can also be used in other industries outside of concretes as well, such as in detergents for automated dish washing machines, and processing recycled paper in the Erco chlorine dioxide process. During such processes, you can treat the liquid streams with a surfactant such as TBP before you get to the absorption phase of the process reducing the foam that one would be dealing with during the Erco chlorine dioxide process.