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(now under DWA) is the German standard for the dimensioning of single-stage activated sludge wastewater treatment plants with secondary clarification. It is widely used in Central Europe and beyond as a benchmark for biological nutrient removal (nitrogen and phosphorus). atv dvwk a 131 epdf top
: A design tool that implements the ATV-A 131 rules, allowing for calculations based on Chemical Oxygen Demand (COD) and various aeration methods. "atv dvwk a 131 epdf top" It looks