An enhanced multiple compartmented (segmented or chambered) supplemental tank system that (i) adds another media to enhance wood chip denitrification, and (ii) includes a component for recycling treated wastewater back to the front end of the system with mainly nitrate-N recycled back and combined with organic carbon (present in wastewater) under anoxic to form nitrogen gas and CO.sub.2. The latter uses an aeration pump and tubing to reduce soluble organics and assist with the conversion of ammonia-N to nitrite-N and nitrate-N.

Embodiments include a vacuum airlift system for treating an aqueous effluent including an upflow liquid column, where the upflow liquid column is configured to retain a fluid, a fluid inlet, the fluid inlet being fluidly coupled with the upflow liquid column, where the fluid inlet is positioned at about the bottom of the upflow liquid column, a downflow liquid column, a fluid outlet, the fluid outlet being fluidly coupled with the downflow liquid column, wherein the fluid outlet is positioned at about the bottom of the downflow liquid column, and a plurality of moving bed biofilm reactors, the plurality of moving bed biofilm reactors being positioned in the upflow liquid column or the downflow liquid column.

The present invention relates to a wastewater treatment apparatus for shortcut nitrogen removal using anaerobic ammonium oxidation (ANAMMOX) and partial nitritation using ammonium oxidizing bacteria (AOB) granules. High-purity AOB granules are formed by means of AOB predominance using a side stream generated during a sludge treatment process. Moreover, the formed AOB granules are supplied to a partial nitritation tank (130) of a main treatment process and thus the partial nitritation is efficiently performed and nitrogen is quickly removed, and thus oxygen and an organic material is reduced compared to an existing method.

An organic wastewater treatment device includes a biological treatment tank in which biological treatment units are connected in series along a flow of organic wastewater. Each biological treatment unit has a pair of an anoxic tank disposed on an upstream side, and an aerobic tank disposed on a downstream side in which a membrane separation device is immersed in activated sludge. The activated sludge returns from a most downstream-side aerobic tank to a most upstream-side anoxic tank through a sludge return path. Whether to stop an operating membrane separation device and whether to start a stopped membrane separation device are determined for each biological treatment unit based on at least one of an inflow amount of the organic wastewater, a tank water level, a transmembrane pressure difference of each membrane separation device, a T-N concentration of the treated water, and an NH3-N concentration of the treated water as an index.

The invention relates to water regeneration in a fish breeding complex combining closed and flow-through water supply systems. A module of a biological filter in a water regeneration system comprises a reservoir, an aerator, a channel for sludge accumulation and discharge and a reservoir bottom sloped in direction of the water movement and, with the water surface, forming a diffuser providing for circulation of water and filler in the biological filter. Fish breeding complex comprises fish breeding pools and a water regeneration system comprising a mud settler-denitrificator, a device for water lifting and aeration, a biological filter, degassing and disinfection units. Each fish breeding pool comprises water oxygenation and disinfection systems, dosage units, water discharge systems and insoluble residues collecting and discharge systems. In the water flow-through mode, water regeneration system is switched off and water supply from an outside source and wastewater discharge are switched on.

The present invention relates to a nitrogen-rich wastewater treatment apparatus using a partial nitritation sequencing batch reactor (SBR) tank, ammonium oxidizing bacteria (AOB) granules and anaerobic ammonium oxidation (ANAMMOX). AOB granules can efficiently be formed by means of a sludge exchange between the SBR tank and an AOB granule production tank. Moreover, partial nitritation is performed by means of allowing the AOB granules to flow into the SBR tank again, nitrogen is quickly removed by means of ANAMMOX without a supply of an external carbon source, and oxygen and an organic material are reduced and a sludge yield decreases compared to an existing method.

A method and apparatus for conditioning the settled solids in the bottom of a wastewater filtration tank to reduce the acidification of the sludge and prevent the excessive growth of undesirable biological growth.

A bubble generator including a container having a side wall and a top wall defining a cavity. An insert is located within the cavity defining a gas path with a trap portion. The gas path being in communication with an exit in the container. The cavity including an opening receiving a gas accumulating within the cavity, the gas path allowing the accumulating gas to escape through the exit once the accumulating gas reaches a predetermined level proximate the trap portion.

The present invention provides a method and apparatus for controlling gas flow rate to the membrane of a membrane aerated biofilm reactor (MABR) in order to effect one or more process outcomes, in particular to reduce or minimize N.sub.2O emissions in the exhaust gas from the MABR while managing gas delivery to mixing apparatus of the MABR and maintaining NH.sub.4 and NO.sub.3 targets in the treated effluent, the method comprising monitoring one or more parameters of the wastewater and the exhaust gas and modulating the supply of feed gas to the membrane based on the one or more parameters in order to control the composition of the exhaust gas.

A process for aerobic treatment of wastewater is provided, which process comprises: (a) supplying a liquid influent comprising wastewater to a reactor containing granular biomass; (b) subjecting the reaction mixture to aerobic conditions comprising a concentration of dissolved oxygen from 0.1 mg/L to 4.0 mg/L, and a hydraulic retention time from 0.5 to 72 hours; (c) separating the reaction mixture into granular biomass and treated wastewater; and (d) recycling separated granular biomass to the reaction mixture. A bioreactor for the process is also disclosed, comprising a reaction vessel provided with an aeration means, a solids separation device with an inlet in the lower part of the reaction vessel having an outlet line for solids arranged to transport separated solids to a riser driven by airlift action and arranged to transport the solids to the upper part of the reaction chamber.