Biological aerated filter for sewage treatment

Abstract

The invention discloses a sewage biological aerated filter. A filter device of the filter comprises a supporting layer and a filter material layer which are arranged from bottom to top, wherein a large-particle-diameter light filler layer is arranged on the upper part of the filter material layer. Filter materials with different particle diameters are used in the biological aerated filter, filter materials with larger particle diameters are used in the supporting layer, filter materials with smaller particle diameters are used in an intermediate layer, and light filter materials with larger particle diameters are added in the surface layer. The light filter materials with larger particle diameters in the surface layer play an effect of pretreatment, so that the surface layer can be used for performing biological treatment and accommodating massive SS (suspending substances), the accumulation speed of the SS amount of the filter materials in the intermediate layer can be greatly retarded, and the time of flow to a critical value can be prolonged, so that the backwashing cycle of the biological filter can be prolonged, the efficiency can be improved, the backwashing water can be saved, and the operation cost can be reduced; relative positions of the structure layers of the filter are not changed after backwashing, the effluent is stable, and the quality is high.

Description

[0001] Technical field: [0002] The invention relates to a sewage aerated biological filter, in particular to an aerated biological filter with three layers of filter materials. Background technique: [0003] Microbial cells can firmly attach to almost any suitable carrier surface in the water environment, and grow and multiply on it. The extracellular polymers extending from the inside of the cell to the outside of the cell make the microbial cells form a fibrous tangle structure, which is convenient called a biofilm. The particulate matter in the feed water of the biological aerated filter is trapped on the surface of the filter and in the voids of the packing, and the excessively grown microorganisms also gather on the surface of the filter and in the voids of the packing. With the continuous operation of the treatment process, the SS in the packing increases, Porosity is reduced. At or near the design flow rate, the total head loss approaches the head necessary to pas...

AI Technical Summary

Problems solved by technology

However, frequent flushing will cause the biofilm to fall off seriously, resulting in the reduction of biomass in the packing layer, which will affect the treatment effect, and easily cause damage and loss of packing, and increase unnecessary backwashing water consumption and power consumption.

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