Abstract: A membrane filtration module having a plurality of permeable, hollow membranes is disclosed. In use, a pressure differential is applied across the walls of the permeable, hollow membranes when immersed in a liquid suspension containing suspended solids. Some of the liquid suspension passes through the walls of the membranes to be drawn off as clarified liquid or permeate, and at least some of the solids are retained on or in the permeable, hollow membranes or otherwise as suspended solids within the liquid suspension. The module has a shell or similar structure that at least partially surrounds the membrane module and substantially effects retaining at least portion of fluid flowed into the membrane module.

Abstract: Hydrophilic porous polymeric membranes with high permeabilities, and processes for the preparation thereof are disclosed. Membranes may be prepared by including a preferably hydrophilic cross-linkable component such as PVP (either by inclusion into the polymer dope prior to casting, or coating or quenching cast membranes); and treating the polymeric microfiltration or ultrafiltration membrane with a crosslinking agent to cross-link said cross-linkable component. Preferred cross-linking agents include Fenton's reagent.

Abstract: A method of cleaning a membrane filtration module (6), the module (6) including at least one membrane (8) located in a feed-containing vessel (7), the membrane (8) having a permeable wall which is subjected to a filtration operation wherein feed containing contaminant matter is applied to one side of the membrane wall and filtrate is withdrawn from the other side of the membrane wall. The method comprising the steps of: suspending the filtration operation; performing a cleaning process on the membrane wall to dislodge contaminant matter therefrom into liquid surrounding the membrane (8); performing a high velocity sweep of the feed-containing vessel (7) to remove the liquid containing the dislodged contaminant matter; and recommencing the filtration operation. An improved gas scouring method is also disclosed.

Abstract: A method and system of treating wastewater that can provide operating flexibility is disclosed. The system is operated with a sequencing batch reactor, which is typically cycling to any of fill, react, settle, decant, and idle stages, to treat the wastewater. The system can further utilize a membrane filtration system to further treat water from the sequencing batch reactor and produce suitable water. A solids-reducing system can be connected to the sequencing batch reactor and reduce an amount of biodegraded solids by converting the character or distribution of microorganisms population in the biomass.

Abstract: A method for removing inert solids from low-yield wastewater treatment processes. The method includes combining wastewater with bacteria-laden sludge in a mainstream reactor to form a mixed liquor, separating the mixed liquor into a clear effluent and activated sludge, returning a first portion of activated sludge to the mainstream reactor, treating a second portion of activated sludge in a sidestream bioreactor prior to returning the second portion of activated sludge to the mainstream reactor, and employing a screening device within the wastewater treatment process to remove inert solids.

Abstract: The invention is directed to a method an apparatus for treating wastewater. The wastewater treatment system includes an aeration system that cycles between biological multiple biological basins. The system also includes one or more membrane basins. A method of the invention includes controlling the introduction of air into each biological basin in response to one or more operating conditions.

Abstract: A synergistic composition is provided for controlling odor from waste products. The composition comprises a combination of nitrate salt, sulfide-consuming compound, pH-elevating compound, sulfide-oxidizing, nitrate-reducing bacteria, and sulfide-oxidizing enzyme. The method includes adding a sufficient amount of the composition to a waste stream to provide sufficient sulfide-consuming compound to effect immediate removal of sulfide. The composition incorporates a pH elevating compound, which both decreases the amount of gaseous H2S and puts the aqueous phase into a pH range where naturally occurring bacteria can more easily metabolize the sulfide. The composition also includes one or more nitrate salts which will accomplish longer term prevention of odors. Specific bacteria are incorporated into the formulation to insure that the nitrate has the right type and amount of bacteria present to prevent formation of and/or consume sulfide.

Abstract: A wastewater treatment system for treating wastewater by processes which include aeration. The system includes an influent conduit for delivery of wastewater to be processed and a treatment tank for processing of the wastewater. Also included is an air conduit for providing compressed air for aeration of the wastewater and a particle size regulation device disposed between the conduit and the tank, wherein the particle size regulation device regulates a size of particles present in the wastewater to provide particle size regulated wastewater. The system also includes at least one aeration jet having a nozzle diameter sized to allow the particle size regulated wastewater to pass through the nozzle.

Abstract: The invention is directed to a wastewater treatment system having an anoxic biological treatment zone, an aerobic biological treatment zone and a separator. The concentration of oxygen in streams within the system is strategically managed for improved removal of nutrient from the wastewater. A source of biodegradable carbon may be introduced to reduce the concentration of oxygen within the system. An effective treatment time under anoxic or aerobic conditions may further be varied.

Abstract: A process for treating BOD, nitrogen and phosphorus containing wastewater, wherein the process includes the steps of providing wastewater influent into an anoxic zone having activated sludge and mixing the wastewater influent with the activated sludge in the anoxic zone to form a mixed liquor. The process further includes providing the mixed liquor into one more further treatment zones and transferring a portion of the mixed liquor from the further treatment zone to a membrane filter wherein a filtrate is separated from sludge. The process also includes selectively recycling at least a portion of the sludge to the anoxic zone as recycled activated sludge.

Abstract: A chloride dioxide generation system made efficient by the use of a minimum number of seals and the use of a sophisticated computerized control system with the chlorine dioxide generation system comprising a) multiple PID loop control, b) a touch screen interface (HMI), c) automatic flow control of chemical precursors, d) a process controller, e) a minimum number of seals, f) a seal-less vacuum eductor, g) a unit design of the ejector; seal-less tubing connector and seal-less manual flowmeters, h) a vacuum eductor to be used with gas supply and other chemical feeds, i) a mass dispersion chlorine flowmeter to accurately supply amount of chlorine gas, j) an optical chlorine dioxide analyzer looped to the process controller and k) an automatic efficiency control screen.

Abstract: A stratified bed of activated carbon having regions of functionalized and non-functionalized activated carbon can be utilized to remove contaminants from fluids such as groundwater. The functionalized region has activated carbon particles comprising a cationic or anionic compound that can remove organic or inorganic anionic or cationic compounds from the fluid to be treated. The non-functionalized region comprises powdered or granular activated carbon or adsorbent media downstream of the functionalized region and captures any leaching species or compounds from the functionalized region.

Abstract: This invention is directed to a wastewater treatment system having a fluidizable media carrying anoxic bacteria in a first treatment zone and a filter membrane positioned in a second treatment zone. A wastewater is contacted with the fluidizable media and further contacted with air and a filter membrane.

Abstract: A method for managing multivalent metal ion concentrations in low-yield wastewater treatment processes. The method includes combining wastewater containing BOD with bacteria-laden sludge in a mainstream reactor to form a mixed liquor, separating the mixed liquor into a clear effluent and an activated sludge stream, returning a first portion of the activated sludge stream to the mainstream reactor, processing a second portion of the activated sludge stream in a sidestream bioreactor, returning at least a portion of the activated sludge stream in the sidestream bioreactor to the mainstream reactor, and adding multivalent metal ions to at least one of the wastewater, the mixed liquor, the activated sludge stream and combinations thereof to reduce the generation of waste activated sludge.

Abstract: The invention is directed to a wastewater treatment system having an anoxic biological treatment zone, an aerobic biological treatment zone and a separator. The concentration of oxygen in streams within the system is strategically managed for improved removal of nutrient from the wastewater. A source of biodegradable carbon may be introduced to reduce the concentration of oxygen within the system. An effective treatment time under anoxic or aerobic conditions may further be varied.

Abstract: This invention is directed to a wastewater treatment system having a fluidizable media carrying anoxic bacteria in a first treatment zone and a filter membrane positioned in a second treatment zone. A wastewater is contacted with the fluidizable media and further contacted with air and a filter membrane.

Abstract: A method and system of providing ultrapure water for semiconductor fabrication operations is provided. The ultrapure water is treated by utilizing a free radical scavenging system and a particulate removal system. The free radical scavenging system can utilize actinic radiation with a free radical precursor compound, such as ammonium persulfate. The particulate removal system can comprise one or more ultrafiltration apparatus. The ultrapure water may be further treated by utilizing ion exchange media and degasification apparatus. A control system can be utilized in feedforward or feedback mode to regulate addition of the precursor compound and the actinic radiation source, and to maintain a temperature of the ultrapure water product.

Abstract: A method and system of providing ultrapure water for semiconductor fabrication operations is provided. The ultrapure water is treated by utilizing a free radical scavenging system and a particulate removal system. The free radical scavenging system can utilize actinic radiation with a free radical precursor compound, such as ammonium persulfate. The particulate removal system can comprise one or more ultrafiltration apparatus. The ultrapure water may be further treated by utilizing ion exchange media and degasification apparatus. A control system can be utilized in feedforward or feedback mode to regulate addition of the precursor compound and the actinic radiation source, and to maintain a temperature of the ultrapure water product.

Abstract: Injection bonded articles comprised of a rigid core and secured together with an elastomeric material network which also forms seals and encapsulates at least a portion of the rigid core. The elastomeric material is selected to be compatible with the material comprising the rigid core to create a chemical and mechanical bond therebetween. Injection bonding and over-molding techniques are used to fabricate an electrodeionization apparatus spacer comprised of mated rigid segments secured by a unitary elastomeric material network that also forms internal and external seals that fluidly isolate one or more of inlet ports, resin cavities, and outlet ports as well as throughports. Injection bonding and over-molding techniques can also be used to fabricate other articles comprised of multiple segments.

Abstract: A projectile of non-lethal composition includes an outer casing that is substantially sealed prior to impact with a target both when the projectile is in a static condition and when the projectile is in a dynamic condition. A marking material is encapsulated within the outer casing prior to impact. The outer casing is configured to deform and unseal upon impact such that the marking material disperses forward via hydraulic action.