A bag assembly for use with a heat exchanger includes a flexible bag having of one or more sheets of polymeric material, the bag having a first end that bounds a first compartment and an opposing second end that bounds a second compartment, a support structure being disposed between the first compartment and the second compartment so that the first compartment is separated and isolated from the second compartment. A first inlet port, a first outlet port, and a first drain port are coupled with the flexible bag so as to communicate with the first compartment. A second inlet port, a second outlet port, and a second drain port are coupled with the flexible bag so as to communicate with the second compartment.

A device for bubbling a gas into a liquid is disclosed. The device comprises a first bubbling apparatus nested inside a second bubbling apparatus. The first bubbling apparatus comprises a gas inlet for receiving the gas and a plurality of first openings for releasing the gas. The second bubbling apparatus at least partially encloses the plurality of first openings of the first bubbling apparatus. The second bubbling apparatus receives the gas from the plurality of first openings. The second bubbling apparatus comprises a plurality of second openings for bubbling the gas into the liquid.

A bag assembly for use with a heat exchanger includes a flexible bag having of one or more sheets of polymeric material, the bag having a first end that bounds a first compartment and an opposing second end that bounds a second compartment, a support structure being disposed between the first compartment and the second compartment so that the first compartment is separated and isolated from the second compartment. A first inlet port, a first outlet port, and a first drain port are coupled with the flexible bag so as to communicate with the first compartment. A second inlet port, a second outlet port, and a second drain port are coupled with the flexible bag so as to communicate with the second compartment.

A method for filtering a gas comprises passing a gas through a compartment of a filter assembly, the filter assembly comprising: an inlet opening; a first outlet opening; a casing comprising polymeric film and bounding the compartment, the compartment communicating with the inlet opening and the first outlet opening; and a first filter at least partially disposed within the compartment. The method further comprising forming a first seal across a first section of the casing at a location between the inlet opening and the first filter to form a first sub-compartment within the casing and severing the casing at a first location.

An apparatus for use with a wastewater treatment tank is described. The apparatus includes a track, pipe modules coupled to the track such that the pipe modules are translatable along the track, and diffusers attached to the pipe modules. Each pipe module defines a respective partially curved mating surface, a respective partially curved mating cavity, and a respective gas passage passing through it. The respective partially curved mating surface of a first pipe module is inserted into the respective partially curved mating cavity of a second pipe module, while the respective partially curved mating surface of the second pipe module is inserted into the respective partially curved mating cavity of a third pipe module. Each gas passage of the pipe modules is in gaseous communication with the other gas passages of the pipe modules. At the same time, each diffuser is in gaseous communication with the gas passages of the pipe modules.

A container assembly includes a flexible bag having an interior surface bounding a chamber and an opposing exterior surface. The bag has a bottom end wall that includes a first sparger and a second sparger. The first sparger and the second sparger each have a flexible first sheet overlying a flexible second sheet, the first sheet and the second sheet being secured together so as to form a sparging area bounded between the first sheet and the second sheet, at least a portion of the first sheet overlying the sparging area being gas permeable so that gas can pass from the sparging area, through the first sheet, and into the chamber.

A mixer-sparger assembly includes a first body portion; a second body portion; a gasket positioned between the first and second body portions to form a seal between the two body portions; an inlet disposed in the first body portion; a flexible tube connected to the inlet; a fluid chamber disposed in the first body portion or the second body portion and in fluidic communication with the inlet; an outlet disposed in the first body portion or the second body portion and in fluidic communication with the fluid chamber; and a plurality of supports extending downwardly from the second body portion to form a self-standing assembly with a space disposed below the second body portion. The first and second body portions have a density greater than about 1.0 g/cm.sup.3, and the inlet, fluid chamber, and outlet in spatial combination are configured to have an axis of rotational symmetry.

A method for filtering a gas comprises passing a gas through a compartment of a filter assembly, the filter assembly comprising: an inlet opening; a first outlet opening; a casing comprising polymeric film and bounding the compartment, the compartment communicating with the inlet opening and the first outlet opening; and a first filter at least partially disposed within the compartment. The method further comprising forming a first seal across a first section of the casing at a location between the inlet opening and the first filter to form a first sub-compartment within the casing and severing the casing at a first location.

A container system includes a collapsible bag having an interior surface at least partially bounding a chamber, the chamber being adapted to hold a fluid. A sparger is disposed within the chamber of the bag, the sparger bounding a compartment and having an inside edge that encircles an opening passing through the sparger. At least a portion of the sparger is gas permeable. A tubular member is coupled to the sparger and is in communication with the compartment. A shaft passes into the chamber of the bag and through the opening of the sparger. A mixing element is secured to the shaft and is disposed within the chamber of the bag.

A diffuser assembly includes a flexible diffuser membrane and a diffuser body. The flexible diffuser membrane defines a circumferential bead. The diffuser body defines a circular plate underlying the flexible diffuser membrane, and an edge ring covering a covered portion of the circumferential bead. The edge ring defines an inside surface that conforms to an outside shape of the covered portion of the circumferential bead. The edge ring is integral to the diffuser body. Such a diffuser assembly may provide a disposable diffuser assembly option with many advantages over conventional technologies such as improved ease of installation, lower weight, and lower cost.