Mesh demisters operate on the principle of inertial impaction.

 The working principle of wire mesh defoamer is as follows:

　　When the gas entrained with liquid foam rises through the wire mesh at a certain speed, due to the inertia of the rising liquid foam, making the liquid foam and wire mesh filaments collision and adhesion on its surface; the liquid foam on the surface of the filament further aggregation and the liquid foam's own gravity settlement, so that the liquid foam to form a larger droplet over the filament flow to the junction of the two intertwined filaments; due to the slipperiness of the filaments, the surface tension of the liquid and the filament of the Capillary effect, making the droplets larger and larger, until the aggregation of droplets large enough to produce its own gravity over the rising gas buoyancy and liquid surface tension of the combined force, the droplets from the filaments were separated from the drop, and flowed to the downstream equipment connected to it. Therefore, as long as the operating gas speed and other conditions are properly selected, the gas through the screen defoamer can achieve the purpose of defoaming.