Signs, causes, and impacts of sludge aging
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Signs, causes, and effects of sludge aging. What are the signs of sludge aging? Can it be determined by microscopic examination to see if protozoa make up the majority, that is, if organisms such as Cyclotella and Paramecium spp. predominate, in order to conclude that the sludge has aged? Is the aging of sludge caused by long-term failure to discharge sludge or an excessively long aerobic zone? The effect of sludge aging is a deterioration in the quality of the effluent, poor sedimentability, and the presence of flocs and particles in the supernatant Can sludge aging be avoided even when sludge is not discharged for an extended period of time?
There seems to be no uniform standard for sludge aging; whether it has aged or not needs to be determined based on factors such as microbial structure, treatment efficiency, the appearance of the sludge, and its physical properties, rather than relying on a single standard. There are many factors that affect sludge aging, such as external temperature, pH value, F/M load, sludge discharge time, and the presence of toxic substances, among others.
It can be seen from the sludge settling ratio!
How can one determine if sludge has aged based on its sedimentation ratio? I happen to have a setup available for this purpose. The sludge no longer receives any nutrients; it is maintained by adding glucose on a daily basis at a rate of 25 kg/day. As a result, the COD level has risen to 2000, while the ammonia nitrogen level is 40. The sludge’s sedimentation ratio has decreased. Since there is no inflow of water, the sludge remains in an aeration state continuously. Is it possible that the sludge has aged, or is it because too little glucose was added? Please help me analyze this situation; I won’t post another thread regarding it. Thank you very much
Sludge aging is not merely a matter of settling properties; in my view, it should be assessed based on MLVSS/MLSS, with emphasis on the proportion of active substances (i.e., biomass) in the sludge. Sludge aging generally occurs due to too high an inorganic content in wastewater, especially under conditions of high calcium and magnesium hardness. Your current condition is not necessarily caused by sludge aging; it could be due to the consumption of flocs resulting from endogenous respiration, and high COD levels may be caused by dispersed microorganisms.
After aging, the sludge exhibits poor sedimentability, becomes loose, and its flocs are smaller in size
To date, there is no widely accepted unified standard for the aging of sludge. There are many factors that affect sludge aging, such as temperature, pH value, F/M load, sludge discharge frequency, water quality conditions, and the presence of toxic substances
Thank you, Wanghuifeng. But how can this situation be improved? Before the shortage of food supply, the sludge system was working well. I welcome everyone’s suggestions
Supply nutrients, accelerate renewal, increase sludge discharge volume
This seems to be caused by low load over a long period of time. Try adding some septic tank sludge; it will provide additional nutrients while helping to re-establish the microbial balance.