Disclosed are a method and a device for treating high ammonia-nitrogen wastewater using a microbial electrolysis cell (MEC) assisted SANI system, including an SANI system, an MEC and a power supply. The cathode chamber and anode chamber of the MEC are separated by a separator and are respectively connected to the cathode and anode of the power supply, and a cathode electrode is enriched with hydrogen autotrophic denitrifying bacteria. The cathode chamber has two main functions. Firstly, a higher denitrification efficiency is achieved due to the enriched hydrogen autotrophic denitrifying bacteria; and secondly, the alkalinity produced in the cathode can adjust the pH of the nitrification chamber. In addition, the cathode chamber can oxidize the residual sulfide in the effluent to meet the discharge standard. This system retains the advantage of less sludge in a SANI process, but also can be applied to the treatment of wastewater with high ammonia-nitrogen.

An electrochemical membrane module for selectively removing pollutants and a preparation method thereof are provided. A Ti/SnO.sub.2Sb substrate electrode is coated with a MI-TiO.sub.2 sol-gel by means of a dip-coating method, and then sintered to obtain a molecular imprinting type Ti/MI-TiO.sub.2/SnO.sub.2Sb coated electrode; the coated electrode is adhered to a ceramic micro-filtration membrane using epoxy resin glue to obtain a Ti/MI-TiO.sub.2/SnO.sub.2Sb MI-anodic conductive composite membrane; the MI-anodic conductive composite membrane is used as an anode, and a titanium mesh is used as a cathode, so that the electrochemical membrane module capable of selectively removing pollutants is obtained. The invention effectively combines an electrochemical micro-filtration membrane and a molecular imprinting technique. When the electrochemical membrane module is used, suspended particles and refractory organics in the sewage are removed, and a highly selective removal of certain refractory pollutants can be achieved.

A method for changing filler pollutant accumulation of a constructed wetland belongs to the field of environmental protection engineering. A coupling device of a microbial fuel cell and a constructed wetland is constructed by using active carbon as a constructed wetland filler, and pond sewage enters into the constructed wetland from the top of the device in an intermittent mode. A titanium mesh is taken as an electron collector for packaging a cathode of the active carbon filler by using the characteristic that electrons are collected by the titanium mesh in a concentrated mode, after stable operation for a period of time, active carbon close to a water surface and active carbon close to the bottom of the titanium mesh are taken out for carrying out specific surface area and biomass measurement, and the accumulation distribution condition of filler pollutants inside the constructed wetland is analyzed.

The invention relates to a microbial fuel cell arrangement comprising a cell reactor. The cell reactor comprises a membrane, which has an active surface and a support surface, as well as a pore size of 10 nm and/or a divalent ion rejection of 50%; an anode and a cathode, which are connected with each other through an external electrical circuit; an influent inlet for liquid medium arranged at the active surface side of the membrane and at least one permeate outlet arranged at the support surface side of the membrane; an influent line connected to the influent inlet; a concentrate outlet, arranged at the active surface side of the membrane and connected to a concentrate line; and pressurisation means for creating pressure difference between the active surface side and support surface side of the membrane. The invention relates also to a method for operating a microbial fuel cell.

In one aspect, the present invention provides reactor designs, component designs, and operating schemes for removing nitrates and chemical oxygen demand from any suitable wastewater stream. In another aspect, the invention also provides reactor designs, component designs, and operating schemes designed to modify and improve pH and water quality in wastewater streams.

Provided is a wastewater treatment process including: (a) circulating wastewater including biodegradable organic material, between an anaerobic digester (AD) and at least one microbial electrolysis cell (MEC), the MEC including an anode and a cathode; (b) applying voltage on said anode and said cathode; and (c) discharging from said AD biogas with a methane fraction of above 70% v/v. Also provided is a biological wastewater treatment system including wastewater inlet, and (i) an anaerobic digester (AD) comprising biogas outlet, and effluent outlet; and (ii) at least one microbial electrolysis cell (MEC) including an anode and a cathode; said AD and said at least one MEC being in liquid communication through liquid circulation lines configured for at least circulating wastewater between said AD and said at least one MEC.

Exemplary embodiments describe apparatuses and related processes for improving mixing and sheer in a fixed film reactor. One process can include recycling at least a portion of a biogas product through at least one sparger below a fixed film zone in the fixed film reactor at conditions sufficient for mixing and sheering the film from an internal structure within the fixed film zone. Often, a cross-sectional area of the fixed film zone fills at least about 90% of a cross-sectional area of the fixed film reactor.

Provided are a water quality purification device, and a water purifier and an aquarium that use the water quality purification device. The water quality purification device includes a component filled with a micro-electrolysis catalyst and a biological filtration component that are connected in series. By utilizing a micro-electrolysis technology, pollutants in water are preprocessed and the biodegradability of the water is improved. A water body processed by the micro-electrolysis catalyst enters the biological filtration component, which can greatly improve the purification efficiency of the biological filter bed. Working together with an adsorption electrode, this structure can effectively stabilize the water quality in the aquarium and greatly reduce the required times of changing water.

Methods are described for treating aqueous solutions, including wastewater, to remove nitrogen-containing compounds using electrochemical processes. The method may be conducted electrolytically under an applied voltage or using endogenous current in a fuel cell arrangement. In some embodiments, energy is reclaimed in the form of hydrogen, methane, and other hydrocarbons or organic molecules. Microorganisms may be used as the catalyst for oxidation of the nitrogen-containing compound and/or reduction of hydrogen ions, carbon dioxide, or bicarbonate. Anaerobic or low-oxygen conditions may be used in the zone.

A purification unit includes a first electric conductor, a second electric conductor, and a third electric conductor. At least a part of the first electric conductor is electrically connected to one surface of the third electric conductor, and at least a part of the second electric conductor is electrically connected to the other surface of the third electric conductor. At least a part of the first electric conductor contacts a gas phase including oxygen, and at least a part of the second electric conductor contacts a treatment target. A purification device includes the purification unit, and a treatment tank for holding, in an inside, the purification unit and wastewater to be purified by the purification unit. The purification unit is installed so at least a part of the first electric conductor contacts the gas phase, and at least a part of the second electric conductor contacts the wastewater.