Abstract: Method and apparatus are provided for reprocessing dry pellets made of waste bio-solids in which the pellets and wet sludge waste bio-solids are supplied to the inlet of a material combining conveyor whose angular position can be adjusted. The pellets are coated with the sludge as they travel along the material combining conveyor to its output which feeds a dryer or oven. By adjusting the speed, length and angular position of the material combining conveyor, the amount of sludge coated onto the pellets can be controlled. The material combining conveyor is preferably a sealed shaftless screw conveyor that extends in a generally veritcal direction so that pellets not properly coated fall by gravity to the conveyor inlet. Dry pellets and wet sludge can be supplied from separate bins to a common feed conveyor such as a shaftless screw conveyor which conveys the mixture to the input of the material combining conveyor.

Abstract: This invention provides apparatus for creating circulation of liquid in a vertical direction within a standing body of such liquid, using a gas bubble generator, without creating excessive turbulence at the surface of the liquid, thus avoiding the formation of foam. A preferred embodiment of this apparatus provides for a vertically extending stackpipe, a gas bubble generator at a lower portion of the stackpipe and means for delivering gas bubbles under pressure to the stackpipe, and, at the upper portion of the stackpipe adjacent the upper discharge opening, means designed to laterally divert a flow of liquid and entrained gas bubbles into a substantially horizontal direction, to cause separation of the gas and liquid and to discharge the gas to a location above the level of the surface of the body of liquid.

Abstract: The invention relates to apparatus for carrying out mixed liquid, gas and solid phase reactions and is intended for use in sewage digestion tanks where the removal of sludge and foam from the tanks is required. A reactor vessel is provided which includes a floating cover vertically movably maintained within the vessel. A device for limiting gas pressure is connected to the vessel below the cover. A buoyancy chamber is provided which is supported by the cover and located therebelow and is intended to be at least partially immersed within the liquid in the vessel. A foam/sludge withdrawal opening is located below the uppermost portion of the buoyancy chamber and connects the interior of the vessel to the exterior. In a preferred embodiment, a ballast member is supported from the cover and extends from the roof to below the buoyancy member.

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: An apparatus is provided for causing circulation within a large body of fluid, especially a fluid comprising long molecules, such as polymer chains. The apparatus comprises a so-called "large bubble" generator, which generates a gas bubble to push the liquid through a series of bent pipes and ultimately into a vertically extending stackpipe. Upon generating a large gas bubble into the stackpipe, the gas acts as a piston within the stackpipe, pushing liquid upwardly therethrough, and thereby drawing liquid into the bottom. In order to prevent "motoring", a sharp-edged baffle plate is provided at a bend in the pipes between the gas-accumulator and the stackpipe. The baffle plate serves to prevent continuing flow of the fluid created by the presence of the long chain molecules.

Abstract: An apparatus is provided for causing circulation within a large body of fluid. The apparatus comprises a "large bubble" generator exposed to the pressure of the fluid at a predetermined level, a vertically extending standpipe, preferably of adjustable height, an inverted siphon between the standpipe and the generator, and a transverse connection between the standpipe and a vertically extending stackpipe. Upon generating a large gas bubble into the stackpipe, the gas acts as a piston within the stackpipe, pushing liquid upwardly therethrough, and thereby drawing liquid into the bottom. The continuous passage of such large bubbles through the stackpipe results in a current flow circulation through the large standing body of liquid.

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: A method and an apparatus for continuously aerating sewage is in the form of a gun with a nozzle for producing a jet of oxygen-containing gas and a plurality of funnels converging downstream and arranged downstream of the nozzle and of one another so as to gradually mix the gas into the liquid and to dispense the resultant mixture into more liquid. The result is that the liquid issuing from the gun does so with an even oxygen content and velocity profile, and that any bubbles which may exist are very small and cannot easily coalesce.

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.