Guidelines for the dimensioning of activated sludge plants outside Germany standard DWA-A 131

In Germany municipal activated sludge plants are usually designed according to DWA Standard DWA-A 131. If DWA-A 131 is applied outside Germany, design parameters have to be adjusted to the process requirements abroad, especially for the case of higher wastwater temperatures and effluent requirements based on daily means instead of qualified grab samples. The adjustments may result in economic advantages by reduced design volumes of the aeration tanks.