An activated sludge process for the treatment of municipal wastewater, particularly applicable to oxidation ditch activated sludge treatment systems which utilize a conventional race track or continuous loop reactor basin configuration. The process removes phosphorus and nitrogen from an activated sludge wastewater treatment system, with an anoxic cycle followed by an aerobic cycle, and followed by a surface wasting cycle until a low flow diurnal period is reached in a diurnal or twenty-four hour period. Automated microprocessor control system using “oxidation-reduction potential” (ORP) and “dissolved oxygen” (DO) as process variable inputs automate aerated and anoxic cycles to optimize phosphorus and nitrogen removal using the available carbon in the influent wastewater resulting in an energy efficient dynamic dissolved oxygen control during the aerated periods.

A method for modifying a wastewater treatment device, the method including: 1) fixing a filling support in a wastewater pool, where the filling support includes a support frame; the support frame includes a hollow shaft, a fixed ring, and at least one vane; 2) adjusting the height of the filling support, until the fixed ring is submerged below the liquid level of the wastewater pool, where the water intake velocity of the wastewater pool is no less than 0.25 m/s, whereby a water current is produced and drives the support frame to rotate; 3) adding a functional liquid into the hollow shaft; and 4) adding an enzyme mixture to the hollow shaft when the rotation speed of the support frame is less than a first preset value, until the rotation speed of the support frame reaches a second preset value.

A recovery device is configured to recover specific material as a dewatering aid from sludge generated in a sewage treatment process. The recovery device includes: a grinder configured to fragment a solid in the sludge to obtain prepared sludge; a separator configured to separate hardly decomposable organic matter and easily decomposable organic matter from the prepared sludge; and an extractor configured to continuously extract hardly decomposable organic matter having specific properties as the dewatering aid from the hardly decomposable organic matter separated by the separator.

A method for modifying a wastewater treatment device, the method including: 1) fixing a filling support in a wastewater pool, where the filling support includes a support frame; the support frame includes a hollow shaft, a fixed ring, and at least one vane; 2) adjusting the height of the filling support, until the fixed ring is submerged below the liquid level of the wastewater pool, where the water intake velocity of the wastewater pool is no less than 0.25 m/s, whereby a water current is produced and drives the support frame to rotate; 3) adding a functional liquid into the hollow shaft; and 4) adding an enzyme mixture to the hollow shaft when the rotation speed of the support frame is less than a first preset value, until the rotation speed of the support frame reaches a second preset value.

A method for treating wastewater is provided. The method uses a cationic mineral composition, which is a cationic clay composition, to assist with flocculating out biomass suspended within the wastewater. The cationic clay composition may be mixed with the wastewater undergoing a wastewater treatment process at numerous injection sites. Mixing the cationic clay composition with wastewater at these injection sites may provide different benefits, wherein these benefits are dependent on the point at which the wastewater is along the wastewater treatment process. The cationic clay composition may be added at one injection site or multiple injection sites, depending on a determination made by the operator.

A cationic mineral composition for treating wastewater is provided. The composition assists with flocculating out biomass suspended within the wastewater. The cationic clay composition may be mixed with the wastewater undergoing a wastewater treatment process at numerous injection sites. Mixing the cationic clay composition with wastewater at these injection sites may provide different benefits, wherein these benefits are dependent on the point at which the wastewater is along the wastewater treatment process. The cationic clay composition may be added at one injection site or multiple injection sites, depending on a determination made by the operator.

A system for growing algae for biofuel production includes a bioreactor configured to contain an algae slurry, an algae-water separator fluidly coupled to the bioreactor to receive and separate the algae slurry into algae and separated water, and an organics treatment system that receives a portion of the separated water and is configured to reduce a concentration of organics in the portion of the separated water. A recycle line conveys the portion of the separated water back to the bioreactor following processing in the organics treatment system, wherein the portion of the separated water is recycled and forms part of the algae slurry reducing the raw water demand of the bioreactor.

The invention provides inoculants for the generation of a biologically active layer in a water treatment or purification device. In some embodiments, the invention provides inoculants for a biologically active zone in a wastewater treatment system or device, for example in municipal wastewater and sewage treatment. In other aspects, the invention provides inoculants for water purification, for example in municipal drinking water purification or in slow sand filtration. Inoculants of the invention increase the effectiveness of the above systems and devices in providing useable water.

A treatment plant and method for controlling a treatment plant suitable for treatment of wastewater. The treatment plant includes a circulation channel housing liquid, a submersible flow generating machine arranged in the circulation channel and generating a liquid flow along the circulation channel, and a control unit that is operatively connected to the flow generating machine. The flow generating machine is driven in operation by the control unit. The method includes the steps of: driving the flow generating machine at a nominal speed, decreasing the rotational speed of the flow generating machine from the set nominal speed, detecting the rotational speed at which the torque of the flow generating machine is equal to a predetermined threshold, and determining the flow velocity of the liquid at the flow generating machine based on a predetermined relationship between the rotational speed of the flow generating machine and the flow velocity of the liquid.

An organic wastewater treatment device includes a biological treatment tank in which biological treatment units are connected in series along a flow of organic wastewater. Each biological treatment unit has a pair of an anoxic tank disposed on an upstream side, and an aerobic tank disposed on a downstream side in which a membrane separation device is immersed in activated sludge. The activated sludge returns from a most downstream-side aerobic tank to a most upstream-side anoxic tank through a sludge return path. Whether to stop an operating membrane separation device and whether to start a stopped membrane separation device are determined for each biological treatment unit based on at least one of an inflow amount of the organic wastewater, a tank water level, a transmembrane pressure difference of each membrane separation device, a T-N concentration of the treated water, and an NH3-N concentration of the treated water as an index.