The Emscher fountain, also called Imhoff tank is a settling tank for mechanical wastewater treatment.
From the sewage water which flows through the settling tank in the longitudinal direction, the mud falls by its own weight and slides down the inclined walls in the actual septic tank. ( Klärwasserzulauf in the picture not shown) The principle of the Emscher fountain was designed in 1906 by Karl Imhoff. International hence the name Imhoff tank is in use. It is a special type of Dortmund fountain. Emscher fountains stand out because of their relatively small Absetzraums by a low hydraulic capacity. Because of the decoupling of sedimentation and septic tank sludge removal may, at the required intervals of mud thrown up the pre-cleaned, solids largely exempt waste not charge again.
Takes its name from the Emscher Emscher fountain Association, which put him in the wastewater treatment plants of the Ruhr Area for the first time. Imhoff was the first plant of this type in Recklinghausen constructed.