Under normal conditions, how many microorganisms should be present per unit volume in the biological treatment tank of a properly functioning sewage treatment plant?
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Everyone, I would like to ask: under normal conditions, how many microorganisms should be present per unit volume in the biological treatment tank of a properly functioning wastewater treatment plant?
The MLSS for conventional activated sludge processes should be between 1500–2500 mg/L. Refer to the \"GB 50014-2006 Code for Design of Outdoor Sewerage Systems\". For SBR-type reactors, it is actually possible to achieve higher values through sludge discharge control, such as 4000 mg/L.
I think the data provided upstairs is not the answer the original poster is looking for. According to the biological expert we consulted, his answer was that under normal conditions, if the concentration of free microorganisms in water exceeds 100,000/ml, it can be considered that bacteria are growing well; such a level of microbial count is sufficient for wastewater treatment. If the microbial count is below the aforementioned value, it indicates that there may be some issue with the system, and it is necessary to identify the cause and take appropriate action.
This data is exactly the data we wanted; thank you very much!:handshake
You’re welcome. We’ve encountered such confusion before as well, so I’ll share as much as I know with everyone.
I have just started studying biological systems. According to what the teacher said, the figures mentioned on the 3rd floor are very accurate; 10 to the power of 5 free bacteria per milliliter represents the minimum value. I hope those who want to help others can provide an accurate answer like the one from the third floor; I support the person from the third floor.
How do I count? I think it’s difficult to determine the bacterial count in activated sludge quickly: both microscopic counting and plate counting methods are not suitable for floc. Could a method combining sludge concentration measurement with sludge activity measurement be used?
Biomass is an important indicator, but it is not possible to measure it specifically during routine operations. In oxidation tanks, it is more common to assess sludge performance by observing protozoa and metazoans; this relies on experience. Find a biochemical system that is operating well and examine its activated sludge, and if possible, consult experienced field technicians for guidance.