Pharmaceutical Industry Trivia - The Powerful Functions of Multi-media Filters

In water treatment systems, there is a kind of equipment that features a simple structure yet plays a crucial role – the multi-media filter, which boasts high-efficiency suspended solids removal capability.

Structural Design

The tank body is made of stainless steel or carbon steel, with an interior coated with epoxy resin or lined with natural rubber to ensure long-term durability of the equipment. For the arrangement of the filter material layer, the bottom is a support layer composed of large-grained cobblestones or quartz sand, which has large gaps and low resistance, facilitating uniform water collection and backwash drainage. Above it is the actual filter medium layer, arranged in a gradient according to density and particle size.

The key to the filter layer design is to ensure natural stratification and recovery after backwashing. Therefore, the upper layer is usually filled with light filter materials of low density and large particle size, and the opposite applies to the lower layer.

Filter Material Combinations

Anthracite-quartz sand combination, three-layer composite filter material, activated carbon combination, etc.

Backwash Regeneration

As the operation time elapses, more impurities are trapped and a filter membrane is formed, leading to a rise in the differential pressure across the filter, which necessitates backwashing.

Combined Processes

Multi-media filters rarely operate independently. When combined with other treatment processes, they can achieve an effect of 1+1>2.