An elongate diffuser (10) comprises a diffuser body (30), and a membrane (20) attached so that introduction of gas at a working pressure into the diffuser displaces part of the membrane (20) from contact with the diffuser body (10) providing an elongate sealed compartment (50) between the membrane (20) and a surface (32) of the diffuser body (30). The gas can pass from the compartment (50) through the membrane (20) for aeration of fluid in which the diffuser (10) is immersed. The diffuser body surface (32) which bounds the compartment (50) is recessed away from the membrane (20) in use, to contribute to the lateral cross sectional area of the compartment (50) and facilitate distribution of gas along the diffuser by the compartment (50). An automatic purge valve for purging water from a gas feed pipe of a diffuser is also disclosed.

An apparatus has a plurality of gas transfer membranes. The apparatus floats in water with the membranes submerged in the water. To treat the water, a gas is supplied to the membranes and is transferred to a biofilm supported on the membranes or to the water. Gas is also used to supply mixing or membrane scouring bubbles to the water. The mixing or scouring bubbles can be provided by a cyclic aeration or other gas supply system, which optionally provides gas at a variable pressure to the membranes in parallel or series with an aerator. Condensates can be removed from the membranes, and exhaust gasses from the membranes can be monitored, optionally through one or more dedicated pipes.

An apparatus has a plurality of gas transfer membranes. The apparatus floats in water with the membranes submerged in the water. To treat the water, a gas is supplied to the membranes and is transferred to a biofilm supported on the membranes or to the water. Gas is also used to supply mixing or membrane scouring bubbles to the water. The mixing or scouring bubbles can be provided by a cyclic aeration or other gas supply system, which optionally provides gas at a variable pressure to the membranes in parallel or series with an aerator. Condensates can be removed from the membranes, and exhaust gasses from the membranes can be monitored, optionally through one or more dedicated pipes.

This application relates to a method of treating wastewater wherein an oxygen infusion system is used to supersaturate wastewater before aerobic biological processes, wherein oxygen is transferred to the wastewater free of oxygen bubbles and achieves a reduction in power demand for the aeration process of wastewater.

Systems and methods for aeration and mixing processes are disclosed.

Systems and methods for aeration and mixing processes are disclosed.

Systems and methods for enabling dynamic volumetric transitioning and segmentation of treatment conditions are disclosed. Such treatment conditions may include, by way of example, systems and methods for dynamically transitioning treatment environments within a reactor for activated sludge treatment processes. Such environments may include anaerobic, anoxic, fermentation, suboxic, and aerobic environments.

Systems and methods for enabling dynamic volumetric transitioning and segmentation of treatment conditions are disclosed. Such treatment conditions may include, by way of example, systems and methods for dynamically transitioning treatment environments within a reactor for activated sludge treatment processes. Such environments may include anaerobic, anoxic, fermentation, suboxic, and aerobic environments.

A mixing aerator is disclosed that includes a housing defining a chamber having a bottom end and a top end, the housing having at least one inlet and at least one outlet; and a longitudinally extending diffuser disposed within the chamber and configured to deliver air bubbles into the chamber when the chamber is filled with liquid. The diffuser includes (a) a tubular elastomeric membrane having a plurality of perforations and, within the tubular elastomeric membrane, (b) an air pipe having a plurality of openings, the openings being larger and fewer than the perforations, and the tubular membrane having upper and lower ends that are sealed against an outer surface of the air pipe.

A system for recovering fat, oil and grease (FOG) from wastewater has multiple annular flotation zones in a concentric configuration surrounding a central column to create progressively increasing surface areas for FOG and solid particles flotation, and thereby enhance FOG recovery and removal. Each flotation zone is equipped with an independent pressurized micro air and ozone bubbles distribution system. A controlled amount of ozone can be injected into the wastewater along with recirculated effluent and micro-size air bubbles. Upon the release of pressurized air-ozone-water mixture, micro-size bubbles are generated and distributed in each flotation zone to effectively float up FOG and solid particles in the wastewater stream.