Technical discussion: The impact of salt content on activated sludge systems
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This post was last edited by hesonchang214 on 2011-5-28 23:12. The chlorine ion concentration in our plant’s wastewater treatment facilities is currently above 1700, while the sodium concentration is above 2800; the sodium ions come from the alkaline solutions. The color of the water has changed recently; please share your opinions. :victory:
When the shock load of NaCl on the activated sludge system used for treating domestic wastewater is less than 5 g/L, the system is not significantly affected, and both the oxygen uptake rate (OUR) of the activated sludge and the removal rate of total organic carbon (TOC) in the system remain normal. When the shock load exceeds 10 g/L, it has an impact on the activated sludge: its OUR decreases by about 35%, while the TOC removal rate drops by around 30%.
Thank you, up above; I’ve finally learned something
Chloride ions have a significant impact on sewage systems
Fluctuations in salt content have a significant impact on activated sludge; generally, when TDS fluctuates by more than 20%, the COD level in the effluent immediately exceeds the allowed limits. Our factory normally monitors conductivity and TDS; we don’t conduct specific ion analysis yet, but fluctuations certainly are not good for microorganisms. Microorganisms with too high levels will dehydrate, while those with too low levels will absorb water and burst. . It’s so annoying!
I learned a little bit before; it’s new knowledge, I’ve gained some insight from it
Such a low level of salinity is considered a minor CASE; it takes just a few days to adapt to it； However, there are few that have an increased salt content alone without any other seasonings added. It might have a significant impact, but the direct cause is often unrelated to these few thousand levels of salinity
Hello, teacher. I’m from Yingkou; you might know me. I’d like to ask for your advice: what is the impact of high TDS levels, those above 5000 milligrams, on activated sludge? I’ve done some research, and it turns out that high TDS levels can disrupt the aggregation of microorganisms; visually, this results in looser flocs. Physiologically, it creates an osmotic pressure within the microbial cells, disrupting the balance of electrolytes there, which in turn affects their activity. I’m not sure if my analysis is correct or not Additionally, what is your view on the high likelihood of sludge bulking in activated sludge processes at wastewater treatment plants in northern regions during winter? I’m a bit puzzled. Thank you. Your old friend. Zhang.
When the TDS exceeds 5000, first determine what the main components are. The sodium chloride concentration is acceptable. If it’s other salts, such as mirabilite, then one needs to be careful. I remember that in some more comprehensive manuals, there is a table showing the limits for conventional salt concentrations. In the case of 5000 mg/L sodium chloride, biochemical activity remains very good. But the profiles of all freshwater indicator microorganisms are invalid. The performance of the flocs generally declines. But it should be noted that if freshwater and saltwater levels fluctuate frequently, it often has a significant impact on microorganisms. Generally, after proper acclimatization, freshwater microorganisms can tolerate salinities of up to about 10,000. 20,000 salinity is the most difficult. 30,000 salinity is actually easier to handle. Isn’t Yingkou coastal? Inoculated with coastal sludge, acclimatization is rapid.