How to classify the salt content in sewage?
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Most of the sewage treatment we use now is traditional activated sludge. The salt content of sewage has requirements. I wonder who can tell me the impact of the salt content in sewage on activated sludge? Now the salt content of the water from my company's sewage station is 1.68g/L. Is this high salt content? What will happen to the sewage treatment? Why is the water sample we titrated out during the COD test now muddy? Thanks! ! ! ! Urgent.
If the salt content in sewage is high, it will easily increase the osmotic pressure and inhibit the production of microorganisms. In severe cases, it will cause cell rupture and death of microorganisms. Your salt concentration is not high enough to become high-salt wastewater, but the salt content is not low. Based on your salt content, it is estimated that the conductivity is above 5,000. In theory, it will definitely have an impact on biochemical treatment. However, there are also some sewage plants that can cultivate some highly salt-tolerant bacteria, and the biochemical effects are quite good. The biochemical processes they generally use are SBR, BAF, etc., and the ordinary activated sludge method is not well understood. I wonder how effective your current process is? In addition, if most of the salts are chlorides, attention should be paid to appropriately increasing the masking dose when titrating COD.
There is no big problem with the ordinary activated sludge method when the salt content is less than 5000ppm, but it takes a long time to acclimate and cultivate microorganisms, and the treatment efficiency is relatively low. The limit salt content is sometimes as high as 30g/l, but the treatment efficiency is also greatly reduced, that is, the microorganisms are inhibited or even partially killed.
Our process uses anaerobic - anoxic - CAST. Now the treatment efficiency in the anaerobic and CAST stages is not very good. Now the sewage looks very muddy and fine mud, and the precipitated water looks a bit white. . .
I measured the conductivity to be 2800. This was measured using the instrument used by our company to make purified water.
If it has just been debugged, what the poster said is normal.
The biochemical effects of the wastewater we treat will not be affected if the salt content is less than 15g/l. Ordinary sludge will have no problem if it is less than 5g/l. Titration turbidity should have nothing to do with the salt content.