Answer: Glass fiber is waterproof but not oil-proof. Oil will form a film on the fiber surface, affecting collection and increasing the functional diameter of the filter element. For this reason, finer fibers must be selected in the design.
The design of the filter layer mainly considers the control of air flow velocity and the physical environment of the filter layer. Only by ensuring that the material has a large enough surface area and the air flow velocity is as low as possible, can the interception, collision and diffusion effects be more effective; on the other hand, the designed filter bed must be thick enough to allow the particles to have sufficient residence time. Finally, there should not be too many fiber layers in the filter element, which will increase the pressure loss and reduce the filter efficiency.
The collection of oil droplets is a physical process. Pressure, flow rate, humidity and the physical properties of the impurities themselves will affect the aggregation results. Therefore, the configuration, arrangement, size and type selection of the filter layer are also critical.
