The dissolved oxygen level in the AO tank doesn’t increase; it stays around 0.2. What’s the use of aeration?
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The dissolved oxygen level in the AO tank doesn’t increase; it stays around 0.2. What’s the use of aeration? The sludge concentration is around 10,000, and the settling ratio is around 90.
There must be too much sludge; it consumes an excessive amount of oxygen
This post was last edited by zhaolijun on 2015-12-31 at 10:54. We have been studying this phenomenon for 8 years; we have encountered it when dealing with chemical wastewater and landfill leachate. At first we were worried, but later we found that the quality of the treated water was good, so we stopped paying attention to it – it just meant there was more foam, and we would take measures to eliminate it. However, the high-concentration activated sludge process requires aeration equipment with strong mixing capabilities to increase KLa. Our aerated jet aeration machines were developed for this purpose; feel free to contact us to obtain more detailed information
It might be that your sludge concentration is too high; typically, the concentration in activated aeration tanks ranges from 3000 to 5000. A sludge concentration of 10,000 is usually the concentration in an MBR tank. The reasons for poor oxygen dissolution efficiency may lie in the choice of your aerator, the design of the air pipes, etc. Regarding the selection of aerators, even in cases with high concentrations of MLSS, it is not necessarily necessary to use micro-pore aerators; medium-pore aerators can also be used.
1. First, ensure that the dissolved oxygen monitoring data is accurate； 2. Adjust the sludge concentration according to the MLSS value specified in the design documents; 10 g/L is too high, as it will result in the waste of a lot of unnecessary air ； 3. An increase in the concentration of organic matter in the incoming water is also one of the main reasons for increased oxygen consumption ； 4. Uneven aeration, low water levels, and local dead zones can also lead to an increase in oxygen consumption.
Too high sludge concentration, defects in the aeration system, and high system load can all be reasons why dissolved oxygen levels do not increase