Methods and systems for controlling nitrous oxide production in a wastewater treatment facility in which wastewater is treated with microbes in a biological reactor. Nitrous oxide production can be controlled by determining an amount of two or more nutrients in the biological reactor, calculating a value that represents a comparison of the values, comparing the calculated value to a threshold value, and optionally taking a corrective action to reduce nitrous oxide production based on the comparison. In one aspect, nitrous oxide production can be controlled by determining an amount of ammonium in the biological reactor, determining an amount of a nitrogen compound that can include nitrite, nitrate, and/or hydroxylamine, calculating a value that compares the amount of ammonium to the amount of the nitrogen compound, and taking a corrective action that changes a system parameter to reduce the nitrous oxide production if the calculated value surpasses a threshold limit.

Methods and systems for removing pollutants from water include one or more filter systems and a hybrid wetland system. Hybrid wetland systems may include a first pipe transporting water from a body of water to a settling tank, a first constructed wetland connected to the settling tank via a second pipe, and a first filter system removing pollutants from water passing through the second pipe. A second filter system is positioned within the first wetland to further remove pollutants. The system also includes a second constructed wetland connected to the first constructed wetland via a third pipe and a water control chamber. Filtered water exiting the first constructed wetland flows through the water control chamber, through the third pipe, and into the second constructed wetland. A fourth pipe extends between the second constructed wetland and the body of water, returning filtered water to the body of water.

Low strength wastewater such as municipal sewage is treated using an anaerobic digester. In some examples, a wastewater stream is separated into a solids rich portion and a solids lean portion. The solids lean portion is treated, for example to remove nitrogen. The solids rich portion is treated in an anaerobic digester, preferably with influent or recuperative thickening. In another example, the wastewater stream is fed to an anaerobic digester and solid-liquid separation stages downstream of the digester return active bacteria and undigested organics to the digester. Both cases may use a process train comprising treatment in an anoxic tank followed by a nitritation tank with a portion of the effluent from the nitritation tank recirculated to the anoxic tank to provide nitritation and denitritation.

The present invention provides a vertical sewage treatment device including an anaerobic chamber, an anoxic chamber, an aerobiotic chamber, and a secondary precipitation chamber, wherein the anaerobic chamber, the anoxic chamber, the aerobiotic chamber, and the secondary precipitation chamber are vertically arranged in sequence from the bottom to the top. According to another aspect, the present invention also provides a sewage treatment method using the foregoing vertical sewage treatment device. The sewage treatment device and method of the present invention have the advantages such as a reduced occupied area, improved oxygenation efficiency, a decreased head loss, a reduced invalid structure volume, and a low heat loss.

The inventive control system can be built using different measurement units and control units. What units are used for building the control system depends on the wastewater treatment plant. This kind of system structure makes it possible to construct a control system that suits for a specific wastewater treatment plant. Therefore, the invention makes it possible to build a control system for different wastewater treatment plants, in such a way that the wastewater plant operates more efficiently.

The present invention relates to a filtering device for a water treatment system comprising a biological treatment device adapted to provide a sludge from wastewater or filtrated wastewater, and/or the biological treatment device being fluidic connectable to or in fluidic connection with the filtering device for receiving filtrated wastewater from the filtering device and for delivering sludge to the filtering device. The filtering device is a cake filtration device comprising a fluid penetrable support structure and the support structure is provided as one or more tubular elements having a filtration cake provided on the inside of the fluid penetrable support structure. The filtering has device an inlet being connectable to receive liquid to be filtered so that the flux of liquid to be filtered is from the inside of the support structure, through the filtration cake and to the outside of the support structure thereby providing a filtrate, an outlet for outletting liquid from the interior of the tubular element, and a filtrate outlet for outletting filtrate from the filtering device. The filtration cake is being provided by deposition of solids from the sludge formed in the biological treatment device.

Disclosed is a method for preparing the same. The method for preparing a carrier including ammonium oxidizing bacteria immobilized therein includes: preparing a PVA-alginate mixed solution containing PVA mixed with alginate; adding sludge containing ammonium oxidizing bacteria and sodium bicarbonate (NaHCO.sub.3) to the PVA-alginate mixed solution to obtain a foaming-beading solution; and dropping the foaming-beading solution to a saturated boric acid solution to obtain beads including sludge immobilized therein, wherein sodium bicarbonate (NaHCO.sub.3) is decomposed to produce carbon dioxide (CO.sub.2) which is discharged to the exterior of the beads to form pores in the beads, when the foaming-beading solution is dropped to the saturated boric acid solution to obtain beads including sludge immobilized therein.

A system and a method comprises a chamber configured to receive a flow of a wastewater mixture from an input. A first baffle wall forms a first channel within the chamber. The wastewater mixture flows from an input to an output of the first channel. A second baffle wall forms a second channel and a third channel within the chamber. The wastewater mixture flows from the output of the first channel to an input of the second channel to an output of the second channel to an input of the third channel to an output of the third channel. The output of the third channel is configured to direct the flow to an output from the first chamber.

A method for treating wastewater includes passing wastewater through a pretreatment component to remove at least portions of one or more contaminants from the wastewater and generate a permeate and passing the permeate through an electro-chemical cell component to remove at least remaining portions of the one or more contaminants and generate an exudate.

A hybrid membrane aerated biofilm reactor (MABR) and activated sludge (AS) system and process are described herein. At least a portion of the AS system includes aerobic mixed liquor, for example in an aerobic tank or zone downstream of a tank or zone containing membrane aerated biofilm modules. The flow of air to the membrane aerated biofilm is modulated considering the ammonia loading rate to the system or to the aerobic mixed liquor, for example according to a diurnal cycle. For example, air flow to the membrane supported biofilm can be below an average or initial air flow rate during a period of low ammonia loading. Air flow to the aerobic mixed liquor may remain essentially constants during the same period. Optionally, mixed liquor around the membrane aerated biofilm modules may be aerated during a period of high ammonia loading.