An apparatus for degrading the organic fraction of sewage by means of active biomass, in particular active sludge particles, comprising: —at least one tank (1) adapted to contain the sewage and said active biomass; —at least one hollow structure (6, 106, 206), adapted to be at least partially immersed in the sewage, provided with at least one first opening (61) for letting in the sewage and with at least one second opening (62) for letting out the sewage, wherein the ratio between the area of the at least one first opening (61) and the area of the at least one second opening (62) is equal to at least 5:1; —air delivery means (7, 70) adapted to introduce air inside said at least one structure (6, 106, 206); wherein said at least one first opening (61) is proximal to said air delivery means (7, 70) and said at least one second opening (62) is distal from said air delivery means (7, 70), so that the air delivery means (7, 70) are adapted to generate a flow of sewage from said at least one first opening (61) to said at least one second opening (62).

A floating aerator that is highly efficient in oxygenating water and wastewater utilizes high-volume, low pressure air that is diffused into a sub-surface oxygen transfer chamber in which water and wastewater is oxygenated. An air lift is created in the oxygen transfer chamber through the discharge of air bubbles in the water column in the aerator. The aerator comprises a floating head having a concave lower surface, a main chamber or barrel that defines the oxygen transfer chamber, and an air diffuser that extends coaxially through the float head and barrel interconnects the float head to the barrel such that there is a discharge slot defined between the lower surface of the float head and the barrel. A ballast ring floats the aerator at the desire level such that a flow of air bubbles and oxygenated water or wastewater are discharged at a subsurface level.

Apparatus for introducing a gas into a main medium, comprising: a main conduit for guiding the main medium, a multitude of injection lines for guiding the gas, wherein each of the injection lines has a respective end section with a respective outlet opening situated within the main conduit, and wherein the end sections are oriented essentially parallel to each other and to the main conduit. With the apparatus a gas can be introduced in particular into waste water for obtaining a biologically activated sludge. Thereby, interaction between the gas and the waste water can be particularly pronounced due to a particularly large liquid-gas-interface caused by particularly extensive turbulences. Further, shear stress acting on particles in the activated sludge can be advantageously low, thus avoiding damage of the biological particles.

Apparatus for introducing a gas into a main medium, comprising: a main conduit for guiding the main medium, a multitude of injection lines for guiding the gas, wherein each of the injection lines has a respective end section with a respective outlet opening situated within the main conduit, and wherein the end sections are oriented essentially parallel to each other and to the main conduit. With the apparatus a gas can be introduced in particular into waste water for obtaining a biologically activated sludge. Thereby, interaction between the gas and the waste water can be particularly pronounced due to a particularly large liquid-gas-interface caused by particularly extensive turbulences. Further, shear stress acting on particles in the activated sludge can be advantageously low, thus avoiding damage of the biological particles.

The present invention relates preferably to ways of biologically treating liquids, and devices applicable in this respect. Processes and devices according to the present invention preferably relates to a system for biological treatment of liquid such as water, the system typically comprising a container having first and second gas supplies for creating a first and second circulating flow of liquid and bio-film carriers and preferably also for aerating the liquid. Preferred embodiments of a container according to the invention comprises an outflow channel extending along, and preferably throughout, a perimeter of an upper part of the container, the flow channel having a fluid penetrable wall section facing inwardly so that fluid may flow from the interior of the container, through the fluid penetrable wall section and into the outflow channel, and an outlet for leading fluid out from the outflow channel.

The present invention relates preferably to ways of biologically treating liquids, and devices applicable in this respect. Processes and devices according to the present invention preferably relates to a system for biological treatment of liquid such as water, the system typically comprising a container having first and second gas supplies for creating a first and second circulating flow of liquid and bio-film carriers and preferably also for aerating the liquid. Preferred embodiments of a container according to the invention comprises an outflow channel extending along, and preferably throughout, a perimeter of an upper part of the container, the flow channel having a fluid penetrable wall section facing inwardly so that fluid may flow from the interior of the container, through the fluid penetrable wall section and into the outflow channel, and an outlet for leading fluid out from the outflow channel.

An air infusion aeration system includes a submersible downdraft tube that carries fluid from its inlet opening to the outlet opening vertically above the inlet opening. The system includes an impeller coupled to the outlet opening and configured to: draw fluid into the inlet opening and provide the drawn fluid into a discharge pressure manifold (DPM) as a fluid stream. The system includes a turbo blower that injects air into the DPM, and the DPM, which includes a center portion and a smaller diameter end portion at opposite ends of the center portion. The DPM is configured to: reduce pressure of the fluid stream at a center of the DPM; within the end portions, receive the air injection into the pressure-reduced fluid stream thereby infusing the injected air into the fluid steam; and forcibly discharge the air-infused fluid stream down toward the body of fluid.

A water treatment system including an enclosure for water to be treated, a multiplicity of biomass carriers located within the enclosure, at least one airlift in the enclosure for raising the water and the biomass carriers and at least one mechanical biomass carrier accumulated residue removal apparatus operative to remove accumulated residue from the biomass carriers.

A vacuum airlift system for treating an aqueous effluent includes an upflow liquid portion, where the upflow liquid portion is configured to retain a fluid, and a fluid inlet, the fluid inlet being fluidly coupled with the upflow liquid portion, where the fluid inlet is positioned at about a bottom of the upflow liquid portion. The vacuum airlift system can also include a downflow liquid portion, where the downflow liquid portion is fluidly coupled with the upflow liquid portion, and a fluid outlet, the fluid outlet being fluidly coupled with the downflow liquid portion, where the fluid outlet is positioned at about a bottom of the downflow liquid portion. The vacuum airlift system can also include a plurality of aerators fed by one or more fluidic oscillators, the plurality of aerators being coupled to the upflow liquid column.

A vacuum airlift system for treating an aqueous effluent includes an upflow liquid portion, where the upflow liquid portion is configured to retain a fluid, and a fluid inlet, the fluid inlet being fluidly coupled with the upflow liquid portion, where the fluid inlet is positioned at about a bottom of the upflow liquid portion. The vacuum airlift system can also include a downflow liquid portion, where the downflow liquid portion is fluidly coupled with the upflow liquid portion, and a fluid outlet, the fluid outlet being fluidly coupled with the downflow liquid portion, where the fluid outlet is positioned at about a bottom of the downflow liquid portion. The vacuum airlift system can also include a plurality of aerators fed by one or more fluidic oscillators, the plurality of aerators being coupled to the upflow liquid column.