Abstract: The present invention relates to a heat exchanger comprising a plurality of parallel-oriented plates or layers securely fixed between two outer walls or frames to define between adjacent plates an area of sealed passages for two heat exchanging fluids, channel or duct means for conducting a hot medium and a cold medium respectively over the layers such that the flow of hot and cold medium takes place in an in-line and a counter-flow fashion, and an external return bend means providing a transfer of the respective medium from one layer to another. Each of the channel means are defined by a pair of layers disposed one next to the other, by straight or directional baffle means, and an internal return bend means located between the adjacent layers.

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: 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: 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, 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 large bubble generator includes a cylindrical gas accumulator tank open at its bottom and having a top wall. An inverted siphon includes a vertical bubble discharge leg coaxial with the tank and projecting upwardly through the tank top wall, and a roughly circular tubular section extending from the bottom of the vertical leg downwardly and outwardly and through the lower part of the tank peripheral wall, and thence upwardly, and thence inwardly into registry with a port in the upper part of the peripheral walls of the tank. Gas supply pipe coupling nipples extend upwardly and outwardly from the upper part of the siphon curved section. The bubble generator is disposed in the lower part of a liquid immersed liquid circulator conduit and is supported by the conduit wall by circumferentially spaced radial struts extending upwardly and outwardly from the accumulator tank to the conduit wall.