A purification unit includes a first electric conductor and a second electric conductor that contacts the first electric conductor. The first electric conductor includes a junction composed of a contact surface with the second electric conductor and an electronic connection section that conducts electrons from the junction to a catalyst. The second electric conductor includes a junction composed of a contact surface with the first electric conductor and an electronic connection section that conducts electrons, which moves from microorganisms to the second electric conductor, to the junction. The electronic connection section of the first electric conductor has higher electrical resistivity than the junction of the first electric conductor, and/or the electronic connection section of the second electric conductor has higher electrical resistivity than the junction of the second electric conductor. The first electric conductor contacts a gas phase including oxygen, and the second electric conductor contacts a treatment target.

A reactor for water splitting or water treatment includes a first electrode, a second electrode electrically coupled to the first electrode, and a proton exchange membrane separating the first electrode and the second electrode. The first electrode includes a first optical fiber coated with a photocatalytic material.

In an apparatus for treating wastewater, e.g sewage water, the water passes through a standard treatment process stream to promote production of dissolved reactive phosphate ions (PO4). Iron (or aluminum) ions are generated by electrochemical means and added to the process stream at one or more locations to produce metal-P coagulant solids removed in part by pump-out, with the substantial remaining P removed by mineralization and filtration in a biological filter such as a sand filter or leach field. In another apparatus, the water passes through a standard aerobic treatment process stream to promote production of dissolved reactive phosphate ions. Iron (or aluminum) ions are generated by electrochemical means and added to the process stream at one or more locations to produce a flocculant of FeP minerals that are separated out by sedimentation, physical filtration or magnetic means.

Supercapacitive bioelectrical systems (SC-BESs) wherein the anode and cathode act as electrodes for a self-powered internal supercapacitor. The BES may further be enhanced by the use of optimized catalysts and enzymes to increase cell voltage and the use of a third capacitive electrode (AdE) short-circuited to the BES cathode and coupled to the BES anode to improve the power output of the self-powered internal supercapacitor.

A Multi-Stage Wastewater Treatment and Hydroponic Farming Device comprises a compact basin, a moving bed biofilm reactor (MBBR), a modified wetland material, at least one microbial fuel cell (MFC) and a distributor. The MBBR and modified wetland material are disposed within the basin. Openings in the distributor retain hydroponic plants. In one example, wastewater enters through the MBBR which performs primary treatment of wastewater. Treated wastewater is further treated by modified wetland material and the MFC which generates electrical energy that supplies other components. Treated wastewater is pumped through the distributor and processed by hydroponic plants which extract growth inducing nutrients from the treated wastewater. Resultant water treated by the device is selectively recycled through various parts of the device or extracted from the device and used for other purposes. In one example, multiple devices are deployed in an area thereby providing self-sustaining, efficient water treatment and farming functionality.

In one aspect, oxidant is employed for enhancing Feammox activity. Briefly, a medium comprises an ammonium containing contaminant, an iron component, an oxidant, and a Feammox bacterium and/or enzyme thereof capable of oxidizing ammonium with reduction of Fe(II) to Fe(III), wherein the oxidant regenerates Fe(III) via Fe(II) oxidation. In some embodiments, the medium is soil and/or water.

Disclosed are modular microbial fuel cell (MFC) devices, systems and methods for treating wastewater and generating electrical energy through a bioelectrochemical waste-to-energy conversion process. In some aspects, a modular MFC system includes a wastewater pretreatment system to receive and pre-treat raw wastewater for feeding pre-treated wastewater for bioelectrochemical processing; one or more modular MFC devices to bioelectrochemically process the pre-treated wastewater by concurrently generating electrical energy and digesting organic contaminants and particulates in the wastewater to yield treated, cleaner water; and a water collection module to receive the treated water from the one or more modular MFC devices and store the treated water and/or route the treated water from the system.

Disclosed are floating micro-aeration unit (FMU) devices, systems and methods for biological sulfide removal from water/wastewater bodies and streams. In some aspects, a system includes a manifold structure including one or more opening to flow air out of an interior of the manifold structure; one or more support structures connected to the manifold structure, in which the one or more support structures are floatable on a surface of a fluid that includes water or a wastewater; and an air source that flows air to the manifold structure, such that the manifold structure supplies the air containing a predetermined amount of oxygen (e.g., less than 0.1 mg/L of oxygen) to oxidize sulfide of the fluid.

The present disclosure discloses a device for electrochemically assisted aerobic composting of organic solid waste and method therefor. The aerobic composting device includes a compost bioreactor, a working electrode, an auxiliary electrode, and a reference electrode. The working electrode is situated on the inner wall of the compost bioreactor, and the reference electrode is situated between the working electrode and the auxiliary electrode. The bottom of the compost bioreactor is provided with a ventilation pipeline with an aeration head. A method for electrochemically assisted aerobic composting of organic solid waste by using the device is also disclosed. By performing electrochemically assisted composting through the composting device of the present disclosure can enrich and utilize electric energy microorganisms to promote the progress of the redox reaction in the compost pile, quickly increase the temperature of the compost, shorten the compost period, and increase the compost maturity.

A wastewater to chemical fuel conversion device is provided that includes a housing having a first chamber and a second chamber, where the first chamber includes a bio-photoanode, where the second chamber includes a photocathode, where a backside of the bio-photoanode abuts a first side of a planatized fluorine doped tin oxide (FTO) glass, where a backside of the photocathode abuts a second side of the FTO glass, where a proton exchange membrane separates the first chamber from the second chamber, where the first chamber includes a wastewater input and a reclaimed water output, where the second chamber includes a solar light input and a H.sub.2 gas output, where the solar light input is disposed for solar light illumination of the first chamber and the second chamber.