Activated sludge tanks for waste water purification plants or the like having round or approximately rectangular ground plan, in particular activated sludge tanks having low levels of pollution

摘要

Activated sludge tanks for waste water purification plants or the like having round or approximately rectangular ground plan and having separate devices for aeration and circulation, a ring-shaped circulation being produced in the tank by means of rotating flat elements and the aeration being produced in a manner known per se by means of aeration elements.