1) Physical methods From the perspective of physics, the methods to eliminate foam mainly include placing baffle or filter screen, mechanical agitation, static electricity, freezing, heating, steam, ray irradiation, high-speed centrifugation, pressure reduction, high-frequency vibration, instantaneous discharge and ultrasonic (acoustic liquid control), which all promote the gas transmission rate at both ends of the liquid film and the liquid discharge of the bubble film to varying degrees, The stability factor of foam is less than the attenuation factor, and the number of foam gradually decreases. However, the common disadvantage of these methods is that their use is strongly constrained by environmental factors, and the defoaming rate is not high. The advantage is that they are environmentally friendly and have a high reuse rate.

2) Chemical methods from the chemical point of view to eliminate foam mainly include chemical reaction method and the method of adding defoamer. Foam bursting process Chemical reaction method during foam bursting process refers to the chemical reaction between the foam and the foaming agent by adding some reagents to generate water insoluble substances, thus reducing the concentration of surfactant in the liquid film and promoting the bursting of foam. However, this method has some shortcomings, such as uncertain foaming agent composition, producing insoluble substances that will harm the system and equipment. The most widely used defoaming method in various industries nowadays is the method of adding defoamers. The biggest advantage of this method is its high defoaming efficiency and convenient use. However, finding suitable and efficient defoamers is the key.