The present invention relates to systems and methods for removing selenate and/or selenite from water and recovering elemental selenium.

The disclosure belongs to the technical field of flue gas treatment and provides a method for denitration of flue gas. The method includes in the presence of anammox bacteria, subjecting a NO.sub.x-containing flue gas and an ammonia water to an anammox reaction.

A device and method for shortcut nitrogen removal and nitrite-oxidizing bacteria activity inhibition are disclosed herein. An embodiment of the present invention provides a hollow fiber diffuser comprising: a plurality of hollow fibers on which bacteria can be attached and grow; and an inlet capable of supplying gas to one sides of the plurality of hollow fibers, wherein the gas includes oxygen and carbon dioxide, nitrite can be produced by the oxygen, and the concentration of oxygen in the gas is adjusted by the oxygen and the carbon dioxide.

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.

The present disclosure provides a water treatment module, a bioreactor comprising one or more of such modules and a receptive water treatment system. Also provided herein is a method making use of the above module, bioreactor and system. The water treatment module comprises (i) at least one elongated gas enclosure comprising a gas inlet and two vertical walls, at least one vertical wall comprising a water-impermeable and gas-permeable membrane having a water-facing side and a gas-facing side, the two vertical walls separating between water external to said enclosure and gas within said enclosure, the gas enclosure being in a rolled or folded configuration to thereby define a convoluted horizontal path and one or more water-treatment spaces formed between opposite water facing sides of the enclosure; and (ii) a diffuser arrangement comprising gas diffusers configured for introducing a stream of gas into the one or more water treatment spaces.

Methods and apparatuses for overcoming biofilm diffusion in water treatment by the addition of the substrate flux within biofilm by advection or convection in order to overcome diffusional limitations.

The present invention relates to an apparatus for collecting and treating wastewater (1) based on biodegradation-recombination-biodegradation process, comprising: a shell (1.1), the space inside the shell is divided into a first chamber (1.2) and a second chamber (1.3) by a divider wall (1.4), wherein: the first chamber (1.2) contains biological medium suitable for heterotrophic microorganisms growth; the second chamber (1.3) contains biological medium suitable for autotrophic microorganisms and heterotrophic microorganisms growth. The present invention also relates to a system for collecting and treating wastewater combining rainwater drainage used for building, comprising: at least one wastewater treatment apparatus (1) above; a indoor pipe system for collecting and transferring wastewater, rainwater comprising a main vertical pipe (2), substantially horizontal branch pipes; and a outdoor pipe system for transferring wastewater combining rainwater drainage comprising a horizontal pipe (3) for connecting the indoor pipe system for collecting and transferring wastewater, rainwater to at least one wastewater treatment apparatus (1) above.

Disclosed a device for preventing and controlling pollutants in the reuse of reclaimed water in agricultural activity areas with extreme water shortage, including A.sup.2/O tank (1), nano-aeration tank (2) and quick soil infiltration device (3) connected in sequence. A.sup.2/O tank (1) is fed with wastewater to be treated, which is treated sequentially in anaerobic, anoxic and aerobic environment, thereafter the supernatant is transported into nano-aeration tank (2). The supernatant treated by nano-aeration tank (2) is transported into quick soil infiltration device (3), and is allowed to flow through one or more layers of fillers laid in quick soil infiltration device (3) to degrade or remove pollutants.

The present invention is directed to systems and methods for removing trichloroethane (TCA), trichloroethene (TCE), and 1,4-dioxane (1,4-D) from contaminated water and wastewater. The system and methods relying on catalyst reduction of TCA and TCE, and the reduced products are degraded by microorganisms that are capable of biodegrading ethane and 1,4-D. In certain embodiments, a catalyst film comprises precious nanoparticles with diameters of 5-40 nm and a biofilm comprising microorganisms that are capable of degrading ethane and 1,4-D are used in a dual-reactor system to remove TCA, TCE, and 1,4-D from contaminated water and wastewater.

A cord for supporting a biofilm has a plurality of yarns. At least one of the yarns comprises a plurality of hollow fiber gas transfer membranes. At least one of the yarns extends along the length of the cord generally in the shape of a spiral. Optionally, one or more of the yarns may comprise one or more reinforcing filaments. In some examples, a reinforcing yarn is wrapped around a core. A module may be made by potting a plurality of the cords in at least one header. A reactor may be made and operated by placing the module in a tank fed with water to be treated and supplying a gas to the module. In use, a biofilm covers the cords to form a membrane biofilm assembly.