Methods and apparatuses for adding gas bubbles to a tank containing liquid at locations that allow the bubbles to rise to the top of the tank are disclosed. One embodiment comprises a membrane filtration system connected to a gas source and a drain. The membrane filtration system draws gas into the system from the gas in response to a reduced pressure profile created by opening a drain. The gas may be air supplied at atmospheric pressure.

Algae harvesting and cultivating systems and methods for producing high concentrations of algae product with minimal energy. In an embodiment, an algae harvesting method is provided for performing dead-end filtration in an algae harvesting system having at least one treatment tank defining a plurality of filtration stages including at least a first filtration stage and a second filtration stage. An algae medium is pulled through the hollow fiber membranes such that a retentate and a permeate are produced.

Provided are a plate-type filter module for water treatment and a filter assembly for water treatment comprising the same. The plate-type filter module for water treatment according to one embodiment of the present invention comprises: a plurality of filter units having a predetermined area and formed in a plate shape; a block frame to which the plurality of filter units is engaged so that the filter units are kept parallel to each other; and a collecting/receiving tube fixed on one side of the block frame and including a plurality of first fittings respectively connected to the plurality of the filter units to allow filtered water produced in the filter units to be introduced thereinto and at least one second fitting for discharging the filtered water introduced through the plurality of first fittings to the outside.

It is to intermittently and effectively generate large bubbles in a liquid phase. A bubble generation device 1 intermittently generates large bubbles a2 in a liquid phase. The bubble generation device 1 includes a bubble storing container 3, a pivot 4, and a pair of edge portion receivers 5a, 5b. The bubble storing container 3 stores bubbles a1 generated by a gas supply nozzle 2 in the liquid. The pivot 4 allows the bubble storing container 3 to pivot thereon, thereby releasing the large bubbles a2 from the bubble storing container 3. The pair of edge portion receivers 5a, 5b receives and blocks an edge portion of the bubble storing container 3 to limit pivot of the bubble storing container 3. An inside of the bubble storing container 3 is partitioned by a partition 30 that is installed in an axial direction of the pivot 4.

An electrochemical membrane module for selectively removing pollutants and a preparation method thereof are provided. A Ti/SnO.sub.2Sb substrate electrode is coated with a MI-TiO.sub.2 sol-gel by means of a dip-coating method, and then sintered to obtain a molecular imprinting type Ti/MI-TiO.sub.2/SnO.sub.2Sb coated electrode; the coated electrode is adhered to a ceramic micro-filtration membrane using epoxy resin glue to obtain a Ti/MI-TiO.sub.2/SnO.sub.2Sb MI-anodic conductive composite membrane; the MI-anodic conductive composite membrane is used as an anode, and a titanium mesh is used as a cathode, so that the electrochemical membrane module capable of selectively removing pollutants is obtained. The invention effectively combines an electrochemical micro-filtration membrane and a molecular imprinting technique. When the electrochemical membrane module is used, suspended particles and refractory organics in the sewage are removed, and a highly selective removal of certain refractory pollutants can be achieved.

Methods, systems, and devices for water treatment or for preventing fouling of components of water treatment systems can include the upstream introduction of nanobubbles in-line and/or in close proximity to a reverse osmosis membrane in the water treatment system. The nanobubbles can bind to and cluster (flocculate) nanoparticles (and possible larger solid particles) so that they can be removed and not foul water purification components such as reverse osmosis membranes. The nanobubbles can also interact with and change some characteristics of nanoparticles and thereby reduce fouling of some system components, such as reverse osmosis membranes, or other components. The systems, methods, and devices disclosed herein can help produce potable water safe for human consumption in a more cost-effective manner, e.g., by reducing maintenance costs and in some cases manufacturing costs.

A header-equipped air diffusion device can sufficiently suppress the intrusion of sludge into the air diffusion device from the header and allow stable operation even with repeated operating and stopping, and a membrane separation activated sludge device. The header-equipped air diffusion device can include an air diffusion device and a header which are immersed in water to be treated. The header includes an air storage unit, on the lower end of which is formed an inlet for the water to be treated, and an air supply part and an air sending part provided on the upper section of the air storage unit. The air sending part and a horizontal tube of the air diffusion device are connected, the air sent from the header is diffused by the air diffusion device, and an air sending of the air sending part in the air storage unit is positioned above an air supply port of the air supply part.

Systems and related methods for purging air burst supply piping of accumulated water prior to delivering pulses of pressurized air to an interior of a screen intake through the air burst supply piping. The systems and methods can include a purge compressor delivering a purging air supply at a head pressure slightly above a head pressure of water in the air burst supply piping, wherein the head pressure of the water is equivalent to a depth at which the intake screen. The system and methods can also include a purge line arranged in a parallel orientation to an air burst supply line, wherein both the purge line and the air burst supply line are operably coupled to a pressurized air tank.

A water filtration module includes filtration elements, each formed from a bundle of hollow fibers. In each element, the end portions of the fibers are included in the coating blocks that do not close them, and a longitudinal hollow tube is arranged at the center of the bundle, so as to open on either side of the coating blocks. Each element includes a cap attached around the lower coating block providing a chamber in hydraulic communication with the hollow fibers and with the central tube. The set of elements are assembled removably in a housing of the module, such that an upper permeate collection chamber of the module is in hydraulic communication with the hollow fibers and the central tubes of each of the elements.

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.