A water purification apparatus includes a flow-rate regulating tank, an aeration tank, a solar power generation unit, and an air blowing unit. The flow-rate regulating tank changes flow-rate of polluted fluid to constantly discharge. The aeration tank purifies the fluid using microorganisms by contacting the polluted fluid supplied from the flow-rate regulating tank to an air, and includes a floatable panel supporting part and a purifying part connected under the panel supporting part to purify the polluted fluid. The solar power generation unit is supported by the panel supporting part to generate electric power using sunlight. The air blowing unit receives the electric power from the solar power generation unit to supply the air in the aeration tank.

The present invention relates to apparatus, methods, and applications for treating wastewater, and more particularly to biological processes for removing pollutants from wastewater. This invention further relates to apparatus and methods for growing microbes on-site at a wastewater treatment facility, and for economically inoculating sufficient microbes to solve various treatment problems rapidly.

The invention relates to bio-electrochemical systems for the generation of methane from organic material and for reducing chemical oxygen demand and nitrogenous waste through denitrification. The invention further relates to an electrode for use in, and a system for, the adaptive control of bio-electrochemical systems as well as a fuel cell.

The present invention relates preferably to ways of biologically treating liquids, and devices applicable in this respect. Processes and devices according to the present invention preferably relates to a system for biological treatment of liquid such as water, the system typically comprising a container having first and second gas supplies for creating a first and second circulating flow of liquid and bio-film carriers and preferably also for aerating the liquid. Preferred embodiments of a container according to the invention comprises an outflow channel extending along, and preferably throughout, a perimeter of an upper part of the container, the flow channel having a fluid penetrable wall section facing inwardly so that fluid may flow from the interior of the container, through the fluid penetrable wall section and into the outflow channel, and an outlet for leading fluid out from the outflow channel.

Disclosed herein are methods and systems for removing carbon dioxide (CO.sub.2) from water and quantifying the carbon so removed, thus facilitating valuation of that carbon for schemes (e.g., Kyoto agreement) that attach financial rewards for capture, sequestration or removal of carbon or CO.sub.2.

The invention relates to a method for nitrogen removal from aqueous medium, comprising steps of (a) converting NH.sub.4.sup.+ in the aqueous medium to NO.sub.2.sup.− by partial aerobic nitrification, (b) partially reducing the obtained NO.sub.2.sup.− to N.sub.2O in anoxic conditions, and (c) decomposing N.sub.2O to N.sub.2 with energy recovery. A mixture of ferrous sulfate and ferric sulfate is used in step (b) for reduction of NO.sub.2.sup.− to N.sub.2O.

We describe a method of determining a food-to-biomass ratio in an aqueous fluid the method comprising: providing an aqueous fluid comprising viable biomass and food for said biomass, and wherein there is insufficient available food to sustain all said viable biomass; using a sensor (for example a respirometer or a sensor for sensing an amount of ammonia, ammonium, nitrates or nitrites) to determine an amount of food in said aqueous fluid available to said biomass; determining a measure of viable biomass in said aqueous fluid by measuring polarisability of viable biomass cells in an AC electric field; and determining a food-to-biomass ratio from said amount of food and said measure of viable biomass.

A system and method of treating wastewater. In one embodiment, the system comprises a biological reactor fluidly connected to a source of wastewater and having a treated wastewater outlet, a fixed film biological reactor connected to the source of wastewater and having a fixed film effluent outlet, and a ballasted system fluidly connected to the fixed film effluent outlet. The ballasted system may comprise a ballast reactor tank configured to provide a ballasted effluent, and a source of ballast material fluidly connected to an inlet of the ballast reactor tank. The system may further comprise a bypass line having an inlet fluidly connected to the source of wastewater, a first outlet fluidly connected to the ballasted system, and a second outlet fluidly connected to the fixed film biological reactor, the bypass line configured to bypass the fixed film biological reactor.

A method and system for wastewater treatment based on dissolved oxygen control by a fuzzy neural network, the method for wastewater treatment comprising the following steps: (1) measuring art inlet water flow rate, an ORP value in an anaerobic tank, a DO value in an aerobic tank, an inlet water COD value, and an actual outlet water COD value; (2) collecting the measured sample data and sending them via a computer to a COD fuzzy neural network predictive model, so as to establish an outlet water COD predicted value, (3) comparing the outlet COD predicted value with the outlet water COD set value, so as to obtain an error and an error change rate, and using them as two input variables to adjust a suitable dissolved oxygen concentration. Accordingly, the on-line prediction and real-time control of dissolved oxygen wastewater treatment are achieved. The accurate control of dissolved oxygen concentration by the present method for wastewater treatment can achieve a saving in energy consumption while ensuring stable running of the sewage treatment system, and the outlet water quality meets the national emission standards.

Chemically oxidizing a wide range of targeted contaminants in soils, sludges, groundwater, process water, and wastewater and assisting in the eventual (over time) biological attenuation of the contaminants utilizing persulfates activated by trivalent metals, such as ferric iron. The use of trivalent metal activated persulfate results in a chemical oxidation process that yields degradation compounds which facilitate further attenuation via biological processes.