A method of removing nitrogen-bound nitrate from at least one of groundwater, surface water, or waste water is disclosed. The method includes providing contaminant-containing water from groundwater, surface water, and/or waste water sources. The method further includes adding the contaminant-containing water to an algal photobioreactor system. The method further includes adding an alga culture to the alga photobioreactor system. The method further includes adjusting temperature, CO.sub.2 concentration, pH, light wavelength, and/or light intensity in the algal photobioreactor system to optimize the growth of the algae. The method further includes separating the algae from the water and harvesting algal biomass.

Disclosed are a green synthesis method of an antibacterial super-porous hydrogel, a product of the antibacterial super-porous hydrogel and an application of the antibacterial super-porous hydrogel to degradation of various pollutants in wastewater treatment. The super-porous hydrogel based on poly (ionic liquid) is prepared by copolymerization of an imidazole type ionic liquid with double bonds and polyethylene glycol diacrylate (PEGDA) as a cross-linker. In the reaction system, water is a good solvent for the monomer ionic liquid and PEGDA, but a poor solvent for the poly (ionic liquid); when an initial concentration of the ionic liquid is higher than 25%, the phase separation typically proceeds through poly(ionic liquid) formation, interconnected networks with macroporous structure could be obtained by photo-crosslinking.

Disclosed herein are systems and methods that provide for increased carrying capacity of bioreactors using silica polymers. Disclosed is a method that includes supplying nutrients and silica polymers containing microorganisms to a bioreactor to form a first suspension and controlling temperature, pressure, and nutrient conditions in the bioreactor to produce a second suspension with increased carrying capacity as compared to a control bioreactor containing microorganisms without the silica polymers.

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.

A method and composition are provided for breaking down a contaminant. A method for breaking down a contaminant in animal drinking water or an organic chemical agent includes providing a plurality of sporulated microbes. A composition for breaking down a contaminant in animal drinking water or an organic chemical agent includes a plurality of sporulated microbes.

A method and composition are provided for breaking down a contaminant. A method for breaking down a contaminant in animal drinking water or an organic chemical agent includes providing a plurality of sporulated microbes. A composition for breaking down a contaminant in animal drinking water or an organic chemical agent includes a plurality of sporulated microbes.

A microbial carrier and a device for treating wastewater are provided. The microbial carrier includes a bacteriophilic material and a plurality of foam cells, wherein the foam cells are disposed in the bacteriophilic material. The bactericidal material is a reaction product of a composite, wherein the composition includes a hydrophobic polyvinyl alcohol and a cross-linking agent, wherein the surface energy of the hydrophobic polyvinyl alcohol is 30 mJ/m.sup.2 to 58 mJ/m.sup.2.

This application relates to a system of treating wastewater wherein an oxygen infusion system is used to supersaturate wastewater before aerobic biological processes, wherein oxygen is transferred to the wastewater free of oxygen bubbles and achieves a reduction in power demand for the aeration process of wastewater.

A method for controlled biomass densification in a biological treatment of a raw influent, includes a step of subjecting the raw influent to a biological treatment of free suspended biomass, thereby producing a biomass comprising activated sludge; a step of separation and/or clarification of the activated sludge, thereby producing an effluent and a RAS; a step of extracting at least part of the RAS and/or part of the activated sludge as a first source of a WAS; a step of external density-based selection of at least part of the RAS and/or part of the activated sludge, thereby generating an overflow intended to be extracted as a second source of WAS, and an underflow comprising dense biomass aggregates; a step of producing and/or sustaining dense biomass aggregates, such as aerobic granular sludge or biofilm, by a dense biomass aggregates generating process, with at least part of the raw influent; a step of subjecting the dense biomass aggregates to the biological treatment; a step of subjecting the dense biomass aggregates of the underflow to the biological treatment and/or to the dense biomass aggregates generating process; thereby obtaining a densified biomass.

A carrier to carry a biofilm in a moving bed biofilm reactor (MBBR) having has improved stability against environmental stresses. The carrier comprises a carrier material, wherein the carrier material comprises at least one high density polyethylene having a bimodal molecular weight distribution, whereby the carrier material has a bimodal or a multimodal molecular weight distribution. Also provided is use of the carrier in a moving bed biofilm reactor (MBBR) process.