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.

A bio-trickling filter box device capable of purifying organic wastewater and generating electricity is provided, which includes battery component(s) and a bio-trickling filter box component. The battery component(s) is provided in the bio-trickling filter box. The other end of each of trickling filter tube(s) is connected with a water tank. A water pump operates to make water flow through the trickling filter tube(s), pass through leakage holes and trickling holes, and drip into the battery component(s) in a water-drop manner, so as to supply an electric apparatus component with power. The bio-trickling filter box component(s) and the battery component(s) are combined, and the long-term impingement of water droplets on the battery component(s) can accumulate electric charge and generate the electricity. so as to provide power required by the electric apparatus component, which forms a biological treatment system that generates the power while treating the wastewater.

A process for enhanced anaerobic digestion of sludge by alcoholization of food waste, comprising steps of: (1) ethanol prefermentation of food waste—feeding the food waste having been crushed into a uniform grain size into an ethanol production reactor, where the food waste is subjected to rapid and efficient anaerobic fermentation activated by addition of yeast and pH adjustment to produce ethanol and obtain a fermentation broth and a fermentation residue; (2) sludge pretreatment—pretreating the sludge after mixing with the fermentation residue; and (3) methanogenesis of anaerobic digestion—subjecting products resulting from the sludge pretreatment to be mixed with the fermentation broth and then to methanogenesis of anaerobic digestion in a methane production reactor. With this process, the sludge and the food waste can be treated efficiently via multi-phase reactions, and the resource recovery and biogas quality can be enhanced.

A microbial electrochemical cell is described herein. The cell includes an anode electrode disposed in an anoxic environment below a water surface. The anode receives electrons from anaerobic decomposition of organic matter or other reduced compounds by microbes in sediment below the water surface. The cell also includes a cathode electrode disposed in an environment at a higher electrochemical potential than the anoxic environment. The cathode is electrically connected to the anode to receive the electrons from the anode. A reference electrode is disposed in the environment at the higher electrochemical potential than the anoxic environment. A potentiostat is electrically connected to each of the anode, the cathode and the reference electrode and is configured to receive electrons from the anode and control distribution of the electrons to the cathode based on a potential difference between the anode and the reference electrode. Methods of remediating aquaculture sediment are also described.

We provide methods, systems, and apparatus for treatment of high chemical oxygen demand wastewater using anaerobic treatment with ceramic membranes. We also provide post-treatment using microbial fuel cells.

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.

Disclosed are devices, systems and methods for operation and control of gravity-fed fluid flows in water and wastewater related systems. The disclosed flow control system uses gravity to provide a flow of a fluid from a fluid source and a motorized flow control device fluidically coupled to the fluid source to control a defined flow rate of the flow by changing a position of an internal volume of the flow control device through which the fluid flows relative to a fixed level of the fluid in the fluid source. The disclosed devices, systems and methods can be used in a wide variety of systems for environmental and low-energy demand applications such as, for example, a wastewater treatment system to control a flow of wastewater in the system.

“Biocathode MCL,” designated for its main bacterial constituents (Marinobacter, Chromatiaceae, and Labrenzia), is a stable microbial community enriched from seawater that forms biofilms on the surfaces of electrodes. These biofilms are effective to perform carbon fixation without the need for external electrical power nor sunlight applied thereto.

Bioelectrochemical systems (BES) having configurations with spiral wound structures and with frame-and-plate structures are provided. Systems may allow for production of an electrical current that is at least partially generated by anodophilic microorganisms connected directly or indirectly to an electrode. A spiral wound or frame-and-plate type bioelectrochemical system may include an anolyte influent point, a catholyte influent point, electrodes, ion selective membranes, mesh separators, gas collection devices, an exterior containment vessel, and one or more external electrical devices.