A hybrid activated iron-biological treatment system and method for treating wastewater. The treatment system includes a combination of zero valent iron, ferrous iron, an iron oxide, and a denitrification microorganism.

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.

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.

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.

Self-delivering digester 100s with self-delivery of accumulated solids are described. A primary waste vessel includes a feeding port for kitchen waste, and an upper output component that connects to a top of the primary waste vessel. The upper output component includes a gas output path from a top of the upper output component, and a floating solids output path that delivers floating solids that overflow from the top of the primary waste vessel to a secondary vessel thereby preventing clogging of the gas output path.

An extraction manifold for extracting digestate from a covered lagoon digester includes a digester vessel being shaped generally as a rectangular prism lacking an upward facing face and having a floor sloping generally downward from an intake face to an extraction face of the digester vessel. The intake face and extraction face are oriented vertically, situated in opposed relation on a longer horizontal axis. Each effluent pipe terminates in an extraction nozzle on one end and an independently addressable actuatable valve on the opposite end. Each actuatable valve communicates with a manifold plenum such that actuation of the valve draws digestate from the floor in a region of the floor adjacent to the extraction face and in proximity to the extraction nozzle. A valve controller actuates valves to remove digestate from the region of the floor adjacent to the extraction face. The valve controller includes sensors to monitor biogas production.

The present invention provides advanced livestock wastewater treatment systems, devices and methods for simultaneous removal of nitrate (nitrite) from treated wastewater at cathode chamber and of organics, suspended solids and malodor (caused by volatile fatty acids) from raw wastewater at anode chamber using anaerobic bioelectrochemical system (BES). The present invention provides a device comprising at least one anode chamber equipped inside with at least one anode, and at least one cathode chamber equipped inside with at least one cathode, wherein the anode chamber is attached to the cathode chamber via separator in order to transport anions or cations between the anode chamber and the cathode chamber.

The embodied invention is directed toward capturing air sources that contain higher concentrations of CO.sub.2 and directing the air to a controlled crop growing environment where a crop will be able to benefit from the higher amounts of CO.sub.2. The air is preferably filtered for dust, monitored for CO.sub.2 levels, and a mixer is used to control the CO.sub.2 level to a desirable amount.

The present disclosure provides a method of preparing a carbonaceous material capable of fixing arsenic and an application thereof. Through biomass pretreatment, biomass pyrolysis and arsenite fixation, a biochar activated by potassium carbonate and an arsenic-containing wastewater containing sulfur-containing substances are mixed and deoxidized, and an anaerobic culture is carried out, to fix arsenic by the biochar activated by potassium carbonate. The present disclosure solves the problems that arsenic is released from the soil and groundwater under anaerobic conditions, the ability of conventional passivating agents to fix arsenic under anaerobic conditions is weakened, and the conventional carbonaceous materials not only cannot fix arsenic, but also accelerate the release of anaerobic arsenic.

An ammonia stripper has an aerator and heat exchanger tubing in a tank. The aerator and coil are preferably attached to a frame to form a removable cassette. The cassette may also include a lid for the tank. The tank is preferably rectangular and optionally can be made with the dimensions of a standard shipping container. In a process, water flows through the tank while air bubbles are produced through the aerator. A heating medium such as water flows through the heat exchanger tubing. A gas containing ammonia is withdrawn from a headspace of the tank.