Envirex Inc.

George W Smith

John W Wittmann

Donald J Thiel

Marc E Roehl

Mark Franklin Pamperin

In an orbal wastewater treatment process including a plurality of concentric, annular basins or channels having surface aeration means, wastewater and recycled activated sludge are mixed in a first channel by a combination of the surface aeration means and introducing an oxygen-containing gas such as air into the lower portion of the zone under conditions which produce a complete mix reaction and sufficient oxygen is supplied to meet the biological oxygen demands of the mixed liquor. The gas is introduced, preferably by a plurality of fine bubble membrane diffusers, in the form of fine bubbles having a diameter of less than about 4 mm. The mixed liquor is sequentially oxidized in second and third channels by a combination of surface aeration means and introducing an oxygen-containing gas into the lower portions of the channels, preferably by fine bubble membrane diffusers.

Orbal wastewater treatment process

Wastewater and recycled activated sludge are homogeneously mixed in a first aeration zone by injecting an oxygen-containing gas such as air into the lower portion of the zone under conditions which produce a complete mix reaction and sufficient oxygen is supplied to meet the biological oxygen demands of the mixed liquor. The gas is introduced, preferably by a plurality of fine bubble membrane diffusers, in the form of fine bubbles having a diameter less than about 4 mm. The bubbles provide both the mixing to keep solids in suspension and the oxygen required to maintain the overall dissolved oxygen content in the first aeration zone as close to 0 as possible. The mixed liquor is sequentially contacted with an oxygen-containing gas in second and third aeration zones under conditions which produce a complete mix reaction, preferably by fine bubble membrane diffusers, clarified and a portion of the settled sludge is recycled to the first aeration zone.

Activated sludge wastewater treatment process

A side channel clarifier for use in wastewater treatment devices employing the circulation of water in a tank having a circuitous path for the purposes of aeration and biological digestion of wastes, wherein the clarifier is mounted in the wall of the channel so that the main flow of water in the tank is undisturbed, and that a portion of that flow is diverted into as quiescent clarification zone, where an inclined baffle collects settled sludge and returns that sludge to the main flow for further decomposition. Siphoning means are provided to ensure the return of a substantial portion of the sludge to the main flow before stagnation occurs and without disrupting the inflow of wastewater into said clarifier. Means are also provided to separate the clarified effluent for further treatment.

Side channel clarifier

An apparatus for use in an activated sludge process for treating wastewater wherein raw sewage or the like is mixed with activated sludge and the resulting mixture is circulated in a confined aerated tank (usually in the form of additional subsurface aeration) so that the mixture follows a predetermined vertical flow cycle through a plurality of flow passageways created by gas impermeable baffle means in order to optimally increase the retention time of aerating air in the tank. The retention time of the air is increased by means of at least one secondary horizontal baffle means specifically designed to collect large bubbles of air trapped beneath said gas-impermeable baffle means and to be permeable to gases, so as to provide additional air/liquid surface area to escaping air. The secondary baffle is situated adjacently above and substantially parallel to the gas impermeable flow directing baffle means.

Vertical looped reactor tank with delayed air release feature

The center clarifier of an endless channel type activated sludge sewage treatment plant is provided with a steep conical floor, a conical baffle and a circular effluent launder. The upper periphery of the baffle includes an overflow trough to receive the scum which is allowed to collect between the trough and the tank wall. The feed to the clarifier is directed through a circular series of spaced submerged ports in the tank wall and toward the conical baffle below the scum collection zone to promote and allow separation of the scum which is removed by overflowing into the scum trough.

Growing community of inventors

Mukwonago, WI, United States of America

George W Smith