The problem of foaming at Aerotank in wastewater treatment operation
1. Cause of load shock:
Causes of Aerotank tank shock load causing foam to float on the surface:
– Waste water input changes changes mutations;
– There is a process of synthesis or sanitation that causes a change in the concentration of pollution in the wastewater;
– The aerotank tank is contaminated with foreign substances outside the receiving source, microorganisms are weak but still receiving normal processing loads;
The phenomenon of shock loading the Aerotank tank causes the foam to rise with expression:
– The pH in the “Aerotank” and behind the “aerotank” begins to decrease, the phenomenon of decrease lasts 2-3 days to show clearly, sometimes it decreases to 4.5-5;
– The water after settling has residue drifting out, microorganisms begin to die;
– The foam floating in the clarifier is usually large, easy to break when it meets water, but it will be smooth and difficult to break when watered a lot to break the large foam.
Image: Aerotank foaming due to load shock
This is the main and common cause. The direction of remedial action is dependent on the operating conditions that provide a remedial operation plan. Depending on the factory, the following main processes are normally performed:
Solution to overcome temporary load shock:
– Minimizing the amount of wastewater received;
– Supplement easily absorbed nutrients for microorganisms;
– Dilution of input wastewater is carried out putting wastewater in to disposing of non-biodegradable waste from the tank;
– If it is a regular source of wastewater that needs to be supplemented with microorganisms, it is necessary to add microorganisms.
Solution to overcome prolonged load shock:
– Identify the source of foreign waste, provide a dilution method if the concentration is too high;
– If the overload lasts for a long time, the flow increases, it is necessary to take measures to increase the capacity of the system;
– Perform microbiological recovery similar to transient load shock.
2. Caused by old mud:
Causes of bubbles in aerotank due to old mud age with manifestations:
– Floating foam is usually small in size;
– Hard to break when watering;
– Floating continuously;
– Foam is accompanied by mud, then it becomes dead mud on the scum.
Image: Aerotank tank foaming due to floating dead old mud
Floating foam caused by old sludge is the common cause nowadays in wastewater treatment works.
The direction of remedial action depends on the cause that the operator offers a solution.
Typically, the following main processes are performed:
– Discharging circulating sludge;
– Adding microorganisms in the tank;
– Increase the Carbon source for the Aerotank tank when necessary.
In this article, I give 2 causes of floating bubbles in the Aerotank tank as above.
In addition to the two reasons mentioned above, there are many other causes of floating foam in the Aerotank tank, such as the development of filamentous microorganisms, nutritional imbalance, incorrect operating mode, and arising technology. error after going into operation…
Depending on each case of operation of the specific wastewater treatment system, the original source can be assessed and a remedy is given.
Please call the hotline of Thanh An Environmental Company (Hotline: 0907071879) for detailed consultation support.