Abstract: An improved apparatus is provided for creating circulation and heat transfer capability within a large body of fluid. The apparatus comprises a vertically extending stackpipe, and large bubble generator means for generating an upward current flow through the stackpipe. Improved efficiency in generating liquid flow is obtained by providing an inclined guide surface to gradually introduce a large bubble from the generator into the stackpipe through a lateral opening into the stackpipe. Most preferably, the cross-sectional area of the stackpipe is expanded beginning at about the level at which the bubble enters the stackpipe and extending to a level at or above the top of the lateral opening into the stackpipe. In this way, interference with the flow of liquid in the stackpipe is minimized and the efficiency of flow generation is maximized.

Abstract: A sewage aerating structure comprising a flue of a kind which accelerates sewage upwardly, and an impact plate against which the sewage collides to shatter gas bubbles which are entrained in the fluid. The impact plate is spaced a specific distance above the exit of the flue. The shattering of the bubbles provides a considerably increased quantity thereof, which increases the gas surface area in contact with the sewage, and thus the aerating efficiency.

Abstract: Cascade Aeration mixing guns for oxygenating sewage are known in the art but cannot be properly scaled up, or paralleled in one unit. A double cascaded unit which incorporates integral baffles is shown so that capacity can be greatly increased, while maintaining efficiency.This invention relates to aerators of the double funnel cascade type, as described in Canadian Pat. No. 937, 610 issued on Dec. 4, 1973 in the name of Jan W. Romanowski.To reduce capital costs in any installation it is generally desirable to increase the size and reduce the numbers of aerators. Unfortunately the size of the aerator - the 12 inch diameter tube - of the above mentioned patent represents a good typical compromise of maximum aeration capacity and maximum aeration efficiency, on oxygen transfer. These quantities are to some extent interdependent, and tests show that both depend upon the depth of submersion. The abbreviated table below is an extract based on test results for such a 12 inch diameter unit.