A system and method for aerating and mixing wastewater that includes fine bubble diffusers located at least partially below a large bubble mixer. At least a portion of the gas discharged from the fine bubble diffusers is captured by the large bubble mixer and is reused by the large bubble mixer to form and release intermittent large bubbles. Prior to being captured by the large bubble mixer, the gas discharged by the fine bubble diffusers can aerate the wastewater. The large bubble mixer includes an accumulator that, upon becoming filled with gas, generates and releases a large bubble. Upon discharge from the large bubble mixer, the large bubbles generated therein may separate into a plurality of coarse bubbles for providing additional oxygen transfer and mixing of the wastewater. The system may include supply lines for supplying gas only to the fine bubble diffuser.

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 bioreactor for a water treatment system includes a tank configured to receive an influent liquid, a separator structure positioned in the tank, the separator structure having a frustoconical shape and defining a downwardly-facing opening proximal to or at a bottom of the separator structure, an interior of the separator structure being in communication with the tank, external to the separator structure, at least via the opening, an aeration vent positioned proximal to a bottom of the tank and configured to direct air into the tank, but not directly into the interior of the separator structure, and an effluent outlet communicating with the interior of in the separator structure, proximal to a top of the separator structure, a relatively clean effluent liquid, in comparison to the influent liquid in the tank, exiting from the separator structure via the effluent outlet.

A bioreactor for a water treatment system includes a tank configured to receive an influent liquid, a separator structure positioned in the tank, the separator structure having a frustoconical shape and defining a downwardly-facing opening proximal to or at a bottom of the separator structure, an interior of the separator structure being in communication with the tank, external to the separator structure, at least via the opening, an aeration vent positioned proximal to a bottom of the tank and configured to direct air into the tank, but not directly into the interior of the separator structure, and an effluent outlet communicating with the interior of in the separator structure, proximal to a top of the separator structure, a relatively clean effluent liquid, in comparison to the influent liquid in the tank, exiting from the separator structure via the effluent outlet.

Increased control and efficiency over the wastewater purification can be achieved through creating conditions that allow the operator to selectively prioritize the digestive function of microorganism in the activated sludge. The gas-dispersion return sludge is created using pure oxygen or oxygen containing trace amounts of ozone as a reactive gas, which is blended with return sludge to create a mixture of gas and liquid, which is passed through an atomizer or a cavitation pump to instantly render the reactive gas to an ultra-fine bubble state. At least a portion of the ultra-fine bubbles dissolve within the gas-dispersion return sludge, activating the dormant microorganisms. Due to a complete or an almost complete absence of biodegradable material in the gas-dispersion return sludge, the microorganism prioritize their digestive function, and when exposed to biodegradable pollutants present in wastewater, digest the pollutants using biochemical pathways different from the ones used in nature.

Increased control and efficiency over the wastewater purification can be achieved through creating conditions that allow the operator to selectively prioritize the digestive function of microorganism in the activated sludge. The gas-dispersion return sludge is created using pure oxygen or oxygen containing trace amounts of ozone as a reactive gas, which is blended with return sludge to create a mixture of gas and liquid, which is passed through an atomizer or a cavitation pump to instantly render the reactive gas to an ultra-fine bubble state. At least a portion of the ultra-fine bubbles dissolve within the gas-dispersion return sludge, activating the dormant microorganisms. Due to a complete or an almost complete absence of biodegradable material in the gas-dispersion return sludge, the microorganism prioritize their digestive function, and when exposed to biodegradable pollutants present in wastewater, digest the pollutants using biochemical pathways different from the ones used in nature.

A device including a housing having a first side, a second side opposed to the first side, and a wall disposed between the first side and the second side. The wall forms at least a partially enclosed space inside the housing. The device also includes a membrane mounted to the wall inside the housing. The device also includes a drop pipe disposed inside the housing and through or around the membrane, the drop pipe having a proximal end and a distal end, the distal end being closer to the second side than the proximal end. The device also includes a diffuser connected to the distal end of the drop pipe.

An aeration device pertaining to the technical field of sewage treatment includes a flow mixing chamber and an air inlet chamber. The flow mixing chamber has a liquid inlet opening, a liquid outlet opening, and an air inlet hole penetrating the chamber wall and located inside the air inlet chamber. The air inlet chamber has an air inlet opening and an interior space whose cross-sectional area is gradually reduced along the liquid flow direction in the flow mixing chamber. The cross-sectional area and number of the air inlet hole can be properly set in order for the mixed fluid produced by the aeration device to have relatively high-density small-diameter air bubbles that contribute to mixing the liquid flow and air flow sufficiently, dissolving oxygen rapidly and sufficiently into the liquid flow, increasing the oxygen dissolution rate of the mixed fluid, and enhancing aeration efficiency.

An aeration device pertaining to the technical field of sewage treatment includes a flow mixing chamber and an air inlet chamber. The flow mixing chamber has a liquid inlet opening, a liquid outlet opening, and an air inlet hole penetrating the chamber wall and located inside the air inlet chamber. The air inlet chamber has an air inlet opening and an interior space whose cross-sectional area is gradually reduced along the liquid flow direction in the flow mixing chamber. The cross-sectional area and number of the air inlet hole can be properly set in order for the mixed fluid produced by the aeration device to have relatively high-density small-diameter air bubbles that contribute to mixing the liquid flow and air flow sufficiently, dissolving oxygen rapidly and sufficiently into the liquid flow, increasing the oxygen dissolution rate of the mixed fluid, and enhancing aeration efficiency.

A wastewater treatment facility with aerators located on the bottom of a lagoon features a bundled group of air supply lines to supply air individually to each submerged aerator. The bundled group of air supply lines floats—and may additionally be supported by a surface-anchored tether line—at the surface of the lagoon, and the air supply lines are individually supplied with air from a manifold located by the side of the lagoon.