48results about How to "Mitigation of membrane fouling" patented technology

Desalination methods that include carbonate compound precipitation are provided. In certain embodiments, feed water is subjected to carbonate compound precipitation conditions prior to desalination. In certain embodiments, desalination waste brine is subjected to carbonate compound precipitation conditions. In yet other embodiments, both feed water and waste brine are subjected to carbonate compound precipitation conditions. Aspects of embodiments of the invention include carbone dioxide sequestration. Embodiments of the invention further employ a precipitate product of the carbonate compound precipitation conditions as a building material, e.g., a cement. Also provided are systems configured for use in methods of the invention.

Filtration systems (40) utilize a pre-treatment method to cause scale formation to occur on particles (94) in the fluid stream (96) rather than on the filter surface and may also destroy microorganisms in the fluid stream. More specifically, but not limited to, a filtration device can be a filtration membrane, such as spiral wound filtration membrane (60), that utilizes an open feed spacer (80), such for example an embossed or printed pattern on the membrane, to create a thin feed spacer channel which replaces a conventional feed spacer mesh material. System (40) further utilizes a treatment device (54) to enable a pulsed power, magnetic, electro-magnetic, electro-static, or hydrodynamic fluid treatment scheme to condition particles in the fluid stream (96) such that scale forming elements precipitate (94) on to the particles in the fluid stream rather than on the filtration surfaces.

High flow, low-pressure ultrafiltration or microfiltration spiral wound membrane cartridges are used in filtration of liquid feedstocks having high suspended solids. Applications may utilize either vacuum or pumping for transmembrane drive pressure (TMP), and gas may optionally be bubbled up through the cartridges with certain feedstocks. Water permeate flux rates as high as 90 gallons per square foot per day (gfd) can be obtained at TMPs below 5 pounds per square inch. By locating each spiral wound cartridge in its own casing and supplying liquid feedstock to an open lower end of the casing, as opposed to submerging such cartridges in a tank filled with feedstock, overall low pressure performance is greatly improved. High permeate flow can be maintained for long periods of time between shutdowns for intensive cleaning. TMP is gradually increased to maintain a substantially constant rate of permeate discharge until a target is reached, indicative of solids accumulation on the membrane surface to an undesirable extent; then backflushing is effected for a short time. Discarding the hold-up volume of feedstock in the cartridge, the backflushing fluid and dislodged solids, allows production to be promptly resumed with fresh feedstock at performance at near original levels.

A novel fluid filtration system that exhibits antifouling properties against a variety of potential foulants includes at least one filtration membrane placed in a cross-flow filtration module. The module is subjected to microwave irradiation at a certain power or intensity over a controlled time interval. At least one microwave generator produces microwaves and may be fixed or movable to treat the fluid. Dislodged foulants are removed by the microwave electromagnetic energy from the filtration membrane and carried away in a cross-flow stream and wasted or recycled back to a feed solution container. The filtration system may use different filtration configurations such as, but not limited to, flat sheet, hollow fiber, spiral wound and tubular membranes. The filtration membrane materials may be polymeric, ceramic, and combinations. The functionalized membranes can be such as, but not limited to, membranes coated or blended or cross-linked with materials displaying strong microwave absorption; and combinations.

The invention discloses a two-dimensional layered composite film and a preparation method and application thereof. The two-dimensional layered composite film comprises a base film; two-dimensional nanosheets which are vertically arranged on the surface of the base film to form a nanosheet layer; and nanospheres which are dispersed among the nanosheet layers. According to the prepared two-dimensional layered composite film, the stability of the layered channel of the film is improved through positive and negative electrostatic assembly, and then the stable nanofiltration separation performance is guaranteed; the size of the layered channel can be effectively regulated and controlled by utilizing the nanospheres with different sizes, so that the film pores can just intercept ions and molecules, the problem of poor molecular ion interception effect when the water flux is large is effectively solved, and the energy consumption in the separation process can be reduced; meanwhile, the hydrophilic nanospheres are introduced to enhance the anti-dirt and antibacterial capabilities, so that the film pollution and film degradation are effectively reduced.

A method and system for controlling dissolved oxygen levels in a secondary treatment system of a wastewater treatment facility that can employ a membrane bioreactor in which oxygen introduction into mixed liquor is controlled to prevent bulking and minimize generation of extra cellular polymeric substances. The control is exercised by insuring that dissolved oxygen levels within the mixed liquor do not fall below a minimum system level at which microorganism stress would occur. This is done by setting a minimum dissolved oxygen level control point equal to a sum of the minimum system level and an adjustment factor determined on the basis of oxygen uptake rate and time delays inherent in sensing oxygen levels and changes thereof within the mixed liquor. The minimum system dissolved oxygen level can be continually calculated on the basis of an inferred food to mass ratio that would vary with sensed mixed liquor suspended solids.

A mixture for treating water in a biological water treatment process is provided comprising an organic-based flocculant, a micronutrient; and a polymer. The flocculant, the micronutrient and the polymer are mixed in a predetermined ratio to enhance said biological water treatment. The mixture is particularly suited to enhancing flocculation of particles, reducing fouling on a surface of a membrane in a membrane bioreactor, improving uptake of phosphorous and/or nitrogen by a biomass in a biological water treatment system, improving bioactivity of a biomass and/or floc in a biological water treatment system and improving flux in a membrane bioreactor.

The invention discloses a double-aeration aerobic granular sludge-membrane bioreactor coupling device and application thereof, and belongs to the technical field of sewage treatment. The device of theinvention comprises a water inlet pipe, an outer cylinder, an inner cylinder, a first aeration assembly, an upper shell, a settling tank, a membrane pool body, a second aeration assembly and a wateroutlet pipe; a lower outer reaction zone is located between the outer cylinder and the inner cylinder, and an inner cavity of the inner cylinder is provided with a lower inner reaction zone; the firstaeration assembly is used for aeration in the lower inner reaction zone; an upper ascend flow zone is located between the upper shell and the settling tank, and an upper descend flow zone is locatedbetween the settling tank and a membrane biological reaction tank; the bottom part of the settling tank is connected with the outer cylinder through a return pipe; the membrane pool body consists of porous plates; a membrane assembly is arranged in the membrane pool body; the second aeration assembly is used for performing aeration scouring on the surface of the membrane assembly; and two ends ofthe water outlet pipe respectively communicate with an inner cavity of the membrane assembly and a clear water tank. The coupling device can fully guarantee the different aeration intensity and aeration rate requirements of the aerobic granular sludge and membrane bioreactor (MBR) membrane assembly.

The invention provides an alternate two-stage aerobic membrane bioreactor. The alternate two-stage aerobic membrane bioreactor comprises a first reactor MRR1, a second reactor MBR2, a regulating tank I, a flow meter, a valve, a centrifugal pump, an automatic-control motor case II, a water storage tank IV, an alkali liquor box III, an acid liquor box V, a first air blower GFJ1, a second air blower GFJ2, a perforated pipe aerating apparatus and an inka aeration apparatus. The invention can realize that after high concentrated organic waste water is hydrolyzed and acidized, the effluent is not subjected to methanogenic-phase reaction but directly enters into the aerobic membrane bioreactor for treatment, so that the effluent has qualified quality; and in the process, the effluent is ensured to be continuous, membrane fouling is retarded, membrane flux is recovered to the maximum limit, and full-automatic control, safety, stability and high efficiency are achieved.