| 摘要 |
<p>An apparatus and method of treating sewage is disclosed. The apparatus includes a modular treating tank which is divided by a perforated baffle or screen into primary and mixing chambers. The mixing zone has a curved or semi-sperical end wall. A mixing and aeration system utilizing a high efficiency ejector withdraws liquid from the mixing chamber and directs the recirculated flow toward the primary chamber across the perforated baffle. In this way, a general circular flow pattern is established from the mixing chamber to the primary chamber across the baffle and return. Thus larger solids are maintained in the primary chamber and are subject to substantially complete organic decomposition therein. The effluent from the treating tank is subsequently chemically disinfected by timed, periodic addition of a chemical e.g. a selected halogen. The method includes the establishment of a recirculating generally oval or circular flow pattern in which liquid is withdrawn from the mixing zone, is aerated and is directed toward the primary chamber. Substantially complete mixing with the incoming sewage occurs in the primary chamber to maintain a uniform concentration of oxygen, feed and purifying organisms throughout the tank volume. By these means, satisfactory treatment results are obtained in reduced time, and high solid concentrations can be maintained in suspension. Sludge is almost completely oxidized, so that little or no sludge accumulates or must be withdrawn from the system for disposal.</p> |
