The vast majority of wastewater treatment plants are equipped with primary sedimentation tanks, where settleable substances are removed, which relieves the subsequent stage significantly. On the other hand, the deducted primary sludge can be pumped directly into the digestion where it significantly contributes to gas production.
In the primary treatment, 20 g of BOD₅ / PE d are removed from the influent, i.e. 1/3 of the BOD₅ contained in the raw wastewater influent.


« back