Efficient backwash method for biofilter

Abstract

The invention relates to an efficient backwash method for a biofilter. The method includes: 1) a water outlet side wall, below a backwash effluent weir, of a newly constructed biofilter is provided with a long strip shaped backwash water outlet and provided with an electric water discharge device; and a water outlet side wall, below a backwash effluent weir, of a biofilter in use is provided with a rectangular or round backwash water outlet and provided with a manual water discharge device; 2) sequentially performing gas washing, gas-water washing and water washing during backwashing of the biofilter; 3) slowly descending a water discharging baffle after sewage discharging; 4) starting a backwashing motor to blow suspended solids to a suspended state; 5) starting a water inlet valve to flush sewage out of the backwash water outlet, and closing the backwash water outlet. The efficient backwash method for the biofilter has advantages that the suspended solids and aged biological membranes generated in the biofilter can be cleared and discharged outside the biofilter thoroughly on the premise that backwash water consumption is not increased; blockage and filter material caking in the biofilter can be reduced, shedding of the biological membranes due to excessive flushing of filter materials can be avoided, and accordingly biochemical treatment effects of the biofilter are improved.

Description

technical field [0001] The invention relates to the technical field of wastewater purification treatment, in particular to a high-efficiency backwashing method for a biological filter. Background technique [0002] The biofilter is usually backwashed by air washing, air washing, and water washing to remove the aging biofilm and suspended solids in the biofilter. When backwashing, a large amount of suspended solids flow out through the backwash weir with the backwash effluent. A clear water area is set above the filter material layer to prevent the filter material from being washed out of the pool during backwash. The water surface of the clear water area is lower than the backwash effluent weir; However, in actual operation, after backwashing, there is still sewage containing a large amount of suspended solids in the clean water area that cannot be discharged. Part of the sewage enters the subsequent treatment process with the effluent of the biofilter, and the other part is...

AI Technical Summary

Problems solved by technology

If there are too many suspended solids deposited on the filter material layer after each backwash, a large amount of backwash water can only be used for flushing, which not only wastes water resources and electric energy, but also washes the biofilm with a large amount of backwash water, which is likely to cause biological Membrane falls off, which affects the effect of biochemical treatment; in addition, the backwash water reservoir and the discharge wastewater pool need to have sufficient volume to provide backwash water and receive backwash drainage, which will also increase the one-time investment

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