An immersed membrane system or process may use measured or calculated process information to optimize one or more process operating parameters to improve performance or reduce operating costs. An on-line process control system or method may use the resistance in series method in operating an immersed membrane water treatment system. A process control system or process may consider resistance values and adjust operational parameters such as membrane aeration frequency factor, membrane aeration flow, permeate flux, permeation duration, backwash flow and duration, relaxation duration or maintenance or recovery chemical cleaning frequencies in order to reduce the operational costs related to membrane fouling removal.

The embodiments disclosed herein include forward osmosis hydration and dewatering devices. The forwards osmosis devices disclosed herein include one or more forward osmosis membranes and one or more barriers. The barriers are configured to protect the forward osmosis membranes from damage, such as damage caused by contact between at least one osmotic agent or another ingredients of the forward osmosis device.

A screen decanter for decanting liquid from a reservoir, comprising at least one rack comprising screens and baffles forming the sides of a cavity; a frame attached to the screens and baffles and providing a barrier so that liquid cannot pass from outside into the cavity without passing through the screens; a patterned perforated drain pipe inside the cavity and leading to an opening through which liquids may drain out from the cavity. The pattern of the openings counteracts the hydrostatic head within the rack such that flow through the screens is uniform at all depths of immersion in the liquid reservoir. Preferably, the screens have a porosity of about 50 micrometers.

A filtration module according to an embodiment of the present invention includes a plurality of hollow fiber membranes held while being aligned in one direction and a pair of holding members that fix both ends of the hollow fiber membranes. In the holding members, an existence region where the hollow fiber membranes exist has a rectangular shape in a direction perpendicular to the direction in which the hollow fiber membranes are aligned; a ratio of an average length of the existence region in a long side direction to an average length of the existence region in a short side direction is 10 or more and 50 or less; an average outer diameter of the hollow fiber membranes is 1 mm or more and 6 mm or less; and a ratio of an average effective length of the hollow fiber membranes between the holding members to the average length of the existence region in the short side direction is 40 or more and 200 or less.

A potting system comprising a potting unit having an integrated compressible seal formed from the same material that the potting unit is composed of.

A method for operating a membrane separation device includes (a) setting a flow amount M(t) of permeated water and extracting the permeated water from the membrane separation device by the set flow amount M(t), and (b) temporarily stopping the extracting the permeated water, when a water level of a first water tank in which the membrane separation device is immersed, a water level of a second water tank in communication with the first tank, or a water level of a third water tank receiving overflowing water from the first water tank becomes lower than a predetermined halt water level. M(t), which is the flow amount of the permeated water during a time period t, satisfies a equation M(t)=KQ(t−1), where K is a gain (K>1), and Q(t−1) is an amount of inflow of the water-to-be-treated during a time period t−1 immediately prior to the time period t.

A method for cleaning a filter membrane in which at least 2 types of cleaning water containing oxidizing agents are prepared, and the filter membrane is cleaned using the cleaning water in an ascending order of the oxidizabilities of the oxidizing agents. Moreover, an apparatus for cleaning a filter membrane of the present invention comprises a means for cleaning the filter membrane using at least 2 types of cleaning water containing oxidizing agents, and the filter membrane is cleaned using the cleaning water in an ascending order of the oxidizabilities of the oxidizing agents. The method and the apparatus for cleaning a filter membrane can efficiently remove polluting substances adhered to a filter membrane while reducing the amounts of oxidizing agents and water to be used, and can maintain the filtration performance for a long period of time.

There is provided a film separation device 1 equipped with a treatment tank 2 receiving a liquid to be treated, a film unit 3 to be immersed in the liquid to be treated, and a guide mechanism 4. The guide mechanism 4 is composed of holding sections 14 and a guide section 15. The holding sections 14 are provided on a side section of a film cassette 5 constituting the film unit 3, and the guide section 15 is fixed to the treatment tank 2. The guide section 15 has a tank-wall fixed section 15a, an upper extension section 15b, a held section 15c, a lower extension section 15d, and a tank-bottom fixed section 15e. When fixing the film unit 3 to the treatment tank 2, the holding sections 14 are fitted to the held section 15c, thereby guiding the film unit 3 to a predetermined position in the treatment tank 2.

A separation-membrane module 1 includes an element block 2 that is formed by arranging, in parallel, a plurality of separation-membrane elements 4 that are formed by arranging a pair of separation-membranes with their respective permeate surfaces in opposition to each other and sealing the edges of the pair of the membranes; and an aeration block 3 that includes an aeration pipe 31 and that is disposed under the element block 2. In the element block 2, at least one upper spacer 8 is disposed in the upper portion of each space between the adjacent separation-membrane elements 4, and a lower spacer 9 is disposed under the upper spacer 8 in each space between the adjacent separation-membrane elements 4. And the leftmost and the rightmost separation-membrane elements 4 of the plurality of the separation-membrane elements 4 are secured to a frame 12 at the lower spacers 9.

Separation methods and systems for converting high concentrations of animal wastes into nutrients and other useful products such as struvite and potassium struvite. Advantageously, the system and methods do not require the addition of external chemicals other than an acid and a base.