Wastewater is treated though primary treatment of the water by way of a micro-sieve to produce a primary effluent and primary sludge. There is secondary treatment of the primary effluent by way of a membrane bioreactor (MBR) or an integrated fixed film activated sludge (IFAS) reactor to produce a secondary effluent and a waste activated sludge. The micro-sieve may have openings of 250 microns or less, for example about 150 microns. In a process, a gas transfer membrane is immersed in water. Pressurized air flows into the gas transfer membrane. An exhaust gas is withdrawn from the gas transfer membrane and used to produce bubbles from an aerator immersed in the water.

A header-equipped air diffusion device can sufficiently suppress the intrusion of sludge into the air diffusion device from the header and allow stable operation even with repeated operating and stopping, and a membrane separation activated sludge device. The header-equipped air diffusion device can include an air diffusion device and a header which are immersed in water to be treated. The header includes an air storage unit, on the lower end of which is formed an inlet for the water to be treated, and an air supply part and an air sending part provided on the upper section of the air storage unit. The air sending part and a horizontal tube of the air diffusion device are connected, the air sent from the header is diffused by the air diffusion device, and an air sending of the air sending part in the air storage unit is positioned above an air supply port of the air supply part.

This publication relates to a method and a system for producing freshwater through a reverse osmosis process in a submerged membrane system requiring a differential pressure over the membrane system. The differential pressure is provided by introducing gas bubbles in the riser device (2) downstream the outlet (7) for fresh water in the riser device (2). The system comprises at least one submerged, reverse osmosis unit (1), with an inlet (4) for water and an outlet (7) for fresh water, a riser device (2) extending from the outlet (7) of the submerged membrane system to at, above or below sea level and a system for providing a low pressure side for the reverse osmosis process.

A cord for supporting a biofilm has a plurality of yarns. At least one of the yarns comprises a plurality of hollow fiber gas transfer membranes. At least one of the yarns extends along the length of the cord generally in the shape of a spiral. Optionally, one or more of the yarns may comprise one or more reinforcing filaments. In some examples, a reinforcing yarn is wrapped around a core. A module may be made by potting a plurality of the cords in at least one header. A reactor may be made and operated by placing the module in a tank fed with water to be treated and supplying a gas to the module. In use, a biofilm covers the cords to form a membrane biofilm assembly.

A filtration apparatus for treating a fluid comprises a vessel, a first partition plate dividing the vessel into first and second chambers and defining a through hole, and a filtration module located within the second chamber and including a body section defining an outer diameter which is greater than the diameter of the through hole in the first partition plate. The apparatus further comprises a reducing connector having a first end secured to the body section of the filtration module and a second end sealed relative to the through hole in the first partition plate to permit communication between the filtration module and the first chamber.

In a disclosed embodiment the apparatus includes a second partition plate such that the vessel is divided into first, second and third chambers, wherein the filtration module is mounted between the partition plates.

An aeration diffuser system includes an air inlet conduit defining an orifice, an air plenum coupled to the air inlet conduit at the orifice, such that the air plenum and the air inlet conduit are in fluid communication, a diffuser secured to a top of the air plenum, and a plurality of pressure transducers including a first pressure transducer at least partially located inside the air inlet conduit, and a second pressure transducer at least partially located inside the air plenum.

An aerator device, a filter system including an aerator device, and a method of aerating a filter using an aerator device. An aerator device includes a housing having an interior cavity; a first plate in the interior cavity and defining a first cavity portion and a second cavity portion thereof, the first plate being spaced apart from a top wall of the housing to define a first opening through which the first cavity portion and the second cavity portion are in communication; and a second plate defining a first chamber and a second chamber of the second cavity portion, the first chamber and the second chamber being in communication with each other below a lower end of the second plate, the housing having an inlet opening in communication with the first cavity portion, and an outlet opening through the top wall and in communication with the second chamber.

Algae harvesting and cultivating systems and methods for producing high concentrations of algae product with minimal energy. In an embodiment, a dead-end filtration system and method includes at least one tank and a plurality hollow fiber membranes positioned in the at least one tank. An algae medium is pulled through the hollow fiber membranes such that a retentate and a permeate are produced.

A cord for supporting a biofilm has a plurality of yarns. At least one of the yarns comprises a plurality of hollow fiber gas transfer membranes. At least one of the yarns extends along the length of the cord generally in the shape of a spiral. Optionally, one or more of the yarns may comprise one or more reinforcing filaments. In some examples, a reinforcing yarn is wrapped around a core. A module may be made by potting a plurality of the cords in at least one header. A reactor may be made and operated by placing the module in a tank fed with water to be treated and supplying a gas to the module. In use, a biofilm covers the cords to form a membrane biofilm assembly.

Hydrogen generation assemblies, hydrogen purification devices, and their components are disclosed. In some embodiments, the devices may include a permeate frame with a membrane support structure having first and second membrane support plates that are free from perforations and that include a plurality of microgrooves configured to provide flow channels for at least part of the permeate stream. In some embodiments, the assemblies may include a return conduit fluidly connecting a buffer tank and a reformate conduit, a return valve assembly configured to manage flow in the return conduit, and a control assembly configured to operate a fuel processing assembly between run and standby modes based, at least in part, on detected pressure in the buffer tank and configured to direct the return valve assembly to allow product hydrogen stream to flow from the buffer tank to the reformate conduit when the fuel processing assembly is in the standby mode.