Abstract: An apparatus for the anaerobic treatment of waste water, including in a same closed enclosure, under a gas pressure, a fermentation zone and a decantation zone, with internal recycling of the slurries from the decantation zone to the fermentation zone, made of at least two attached identical cells in mutual communication. The two cells operate alternately and reciprocally as a fermentation cell and as a decantation cell. Each cell is fitted out, in order to be fed while it operates as a decantation cell, with a gas-lift transfer device with two branches, one of the branches opening into the cell which is attached to that where it is placed.

Abstract: A device for the collection of water from a granular material bed filter includes means for injecting water and air through the filtration bed as well as an outer chute provided with a weir for the discharge of water, characterized in that it is made of a storage capacity placed between the filter and the discharge chute and defined by a vertical perforated wall such as a grid situated in vertical alignment with the filter vertical wall, and a plane slanting inwardly to the inside of the filter, said slanting plane connecting the weir for the discharge of the water via the chute to the filter wall situated below the vertical perforated wall such as the grid.

Abstract: A reactor for aerobically or non-aerobically treating a fluid flowing from the bottom to the top of the reactor through a fluidized bed of granular material. The reactor includes a base having an orifice therein, through which fluid flows into the reactor and in which gas is added to the fluid. A horizontally extending plate surrounded by a supple membrane faces the base and the orifice. The plate and the membrane form a valve for preventing fluid from the reactor from entering the orifice in the event fluid flow into the reactor ceases. The gas entrains the granular material so that when the gasified fluid passes upward through the granular material a three-phase liquid-gas-granular material mixture is produced. The upper portion of the reactor includes a device for disembedding the granular material from the fluid, a device for degasing the three-phase liquid-gas-granular material mixture, and a device for separating the granular material from the fluid to produce a fluid discharge.

Abstract: A horizontal-axis aerator for use in a waste water purification system includes a cylinder having a horizontal axis, a first series of parallel blades on the surface of the cylinder and extending in directions nonparallel to the axis, and a second series of parallel blades on the surface of the cylinder and extending in directions nonparallel to the axis. The directions of the first series of blades are opposite to the directions of the second series of blades, with respect to the axis. The first and second series of blades intersect each other, such that upon the aerator being partially immersed in a body of waste water to be treated and being rotated therein, at any rotational position of the aerator about the axis, a constant portion of the total blade length of all of the blades of the aerator will be immersed in the waste water.

Abstract: An apparatus for introducing gas into a liquid mass, particularly at a certain depth therein, includes at least one emulsifying tube adapted to be positioned within the liquid mass and to be vertically aligned above a gas port. The tube has at a lower portion thereof structure for receiving therein gas from the gas port and liquid from the liquid mass, such that the gas and liquid form an emulsion flowing upwardly through the tube. The tube has at an upper portion thereof, structure opening downwardly into the liquid mass for reversing the flow of the emulsion and for then discharging the emulsion downwardly into the liquid mass. Such reversing and discharging structure may be the form of a bend in the upper end of the tube or in the form of a hood mounted above and confronting the upper open end of the tube.

Abstract: A circular decanter includes a stationary hollow column rotatably supporting a bridge which spans the decanter. A trough is integral with the bridge and rotates therewith, whereby sludge drawn by vacuum from the bottom of the decanter is collected in the trough. A sludge evacuation duct is positioned centrally within the hollow column. That portion of the trough which is closest to the column is formed as a siphon having an upstream branch extending downwardly into the sludge collection chamber of the trough and a downstream branch extending downwardly into the sludge evacuation duct. An electric motor for rotating the bridge, trough and siphon is positioned above the column and includes rotating elements attached to the siphon and non-rotating elements. The power supply cables for the electric motor are led upwardly through the column, the sludge evacuation duct and the downstream branch of the siphon and are enclosed within a stationary casing and tube.