1, the nutrition is unbalanced, and the proportion of C, N and P is out of balance, which leads to small floc particles and is not easy to settle;

2, the aeration amount is too large, the dissolved oxygen rises, and it is not easy to settle;

3. Filamentous bacteria swell;

4. Sludge flocculation;

5. The water quality is unstable, and the load is too large or too small;

6. Residual sludge.

In view of the above points, the following corresponding countermeasures can be made:

1, adding certain nutrients and trace elements, so that microorganisms can fully absorb nutrients during their growth;

2. Adjust the ventilation rate. According to the actual situation, it is between 1.5-3 in the case of activated sludge process and 2-4 in the case of contact oxidation;

3. There are no effective measures to control the expansion of filamentous bacteria. The aeration rate can be adjusted appropriately, and then some flocculants can be added to increase the sludge discharge. If it really doesn't work, adjust it from the beginning;

4. Find out the cause of sludge flocculation and see if there is bacterial poisoning or insufficient nutrition;

5, give full play to the role of regulating pool, try to make the water quality uniform, or add nutrients to adjust or add a small amount of water;

6. Accelerate sludge discharge.

Extended data:

Complex microorganisms in activated sludge and organic nutrients in wastewater form a complex food chain. Heterotrophic bacteria and saprophytic fungi are the first to undertake the task of purification, and bacteria, especially spherical bacteria, play the most critical role.

The well-run activated sludge is a bacterial micelle composed of filamentous bacteria and spherical bacteria. With the normal operation of activated sludge, bacteria multiply and begin to grow protozoa, which are the primary predators of bacteria.

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