The Bio filter media is selected as a main raw material for several kinds of polyolefins and polyamides, which are resistant to corrosion, temperature and aging, and mixed with hydrophilic, absorbent, heat-resistant oxygen and other additives, and adopts special wire drawing. It is manufactured by the silk hair processing technology. Due to the excellent material selection and process formula, the Bio filter media can be stretched in a three-dimensional and uniform manner in an effective area, and the gas, water, and biofilm can be fully mixed and contacted and exchanged，and do a good metabolism.
Due to the special nature of materials, Bio filter media should not be stored in open air for long periods of time, and should be protected from direct UV radiation and freezing cold. When assembling and suspending biological fillers, they should be tightened so as to avoid mutual winding during operation. Soaking in fresh water, and a short period of aeration, to maximize the stretch of the silk, to ensure the quality of water.
There are also many common types of Bio filter media. One is a semi-soft filler consisting of a single piece of packing, a plastic casing, and a central rope. It has a special structure and hydraulic properties. It has a large porosity and a small flow resistance. When the water passes through the packing layer, a clear turbulent flow state can be generated, the contact efficiency between the water and the biofilm can be increased, and the ability of removing the contaminant can be increased. Not only that, but also a certain degree of rigidity and flexibility of the filler, with a strong re-distribution of water, gas capacity.
The other is a combination of fillers, which focus on the soft and semi-soft structural characteristics, which are also subdivided into modular double ring packing, modular porous ring packing, elastic three-dimensional packing and other varieties to meet different application needs. There is also an elastic three-dimensional filler. The filler is made of all-plastic material and has a longer life than the soft filler. Each filament vibrates when aerated. Therefore, the gap of the filler is variable without clumping or blocking and the biofilm is easy to be updated. At present, more hydrolytic acidification stages are used in the treatment of refractory organics to improve the biodegradability of wastewater.
In addition, the suspension filler is also a kind of Bio filter media. It exists in suspension in the aeration tank and its amount is about 20% to 70% of the aeration tank volume, like multi-faced hollow ball filler, built-in type Float packing can belong to suspension type bio-filler.