Disclosed are methods of treating wastewater using a membrane bioreactor and achieving a target phosphorus concentration for the membrane permeate stream. These methods include the steps of dosing a wastewater stream with a rare earth clarifying agent and passing the dosed wastewater stream through the membrane to obtain a membrane permeate stream with a permeate concentration that is less than the phosphorus concentration of the influent stream. This permeate concentration also can be equal to or less than a target phosphorus concentration. In the methods as disclosed herein, the rare earth clarifying agent can be chloride salts of one or more rare earth elements and in certain embodiments, the rare earth clarifying agent can be CeCl.sub.3 and LaCl.sub.3.

Embodiments described herein relate to methods and systems for dewatering solutions via forward osmosis.

A portable water conditioning system is provided that includes an incoming water inlet; a reverse osmosis stage in fluid communication with the incoming water inlet, the reverse osmosis stage having a permeate outlet and a concentrate outlet; a diversion device having a diversion valve, the diversion valve placing the concentrate outlet in fluid communication with a waste water outlet; a deionizing stage in fluid communication with a pure water outlet; a bypass valve configured to selectively place the permeate outlet in fluid communication with one or more of the waste water outlet, the deionizing stage, and the pure water outlet; and a controller configured to control the diversion device and the bypass valve to provide water at the pure water outlet of a desired condition.

This specification describes a method for lowering the content of monovalent ions in a final concentrate of a nanofiltration system relative to a brine and a corresponding nanofiltration system. The nanofiltration system comprises at least three stages of nanofiltration, wherein the concentrate from each segment flows into the next segment. A feed stream is sent into one stage to generate a concentrate stream, and a first portion of the concentrate stream is recirculated to the one stage. The pH of the feed stream is controlled in a range of 2-7. The temperature of the feed stream is in a range of 20-60 C. The feed stream includes the recirculated concentrate stream and at least part of a concentrate generated from an upstream stage. The method and the system described herein can reduce the concentration of monovalent ions in the final concentrate during a nanofiltration separation process.

Disclosed is a process for enriching silicate content in drinking water that includes separating raw water via reverse osmosis into a permeate comprising demineralised raw water and a retentate comprising mineral enriched raw water. The permeate is mixed with a water glass solution comprising sodium silicate and/or potassium silicate. An ion exchange process is used to reduce the concentration of sodium and/or potassium ions in at least part of the mixture. At least part of the retentate is supplied to the mixture after reducing the concentration of sodium and/or potassium ions to provide a silicate-enriched drinking water. Also disclosed is an apparatus for producing a drinking water enriched with silicate. The apparatus includes a reverse osmosis unit, a mixing unit, an ion exchanger, and a feed unit for feeding at least part of the retentate to the mixture after reducing the concentration of sodium and/or potassium ions.

This membrane separation device includes: an organic substance concentration measurement means which measures the organic substance concentration in the treatment target water; a pressure measurement unit which measures a transmembrane pressure of the separation membrane; transmembrane pressure increase speed comparing means which compares a transmembrane pressure increase speed selected on the basis of the value of the organic substance concentration measured by the organic substance concentration measurement means, with a transmembrane pressure increase speed calculated from the transmembrane pressure measured by the pressure measurement unit; and a control unit which controls the membrane surface aeration flow amount of the membrane surface aeration device, wherein the control unit changes the membrane surface aeration flow amount on the basis of the difference between the transmembrane pressure increase speeds, obtained by the transmembrane pressure increase speed comparing means.

This membrane separation device includes: an organic substance concentration measurement means which measures the organic substance concentration in the treatment target water; a pressure measurement unit which measures a transmembrane pressure of the separation membrane; transmembrane pressure increase speed comparing means which compares a transmembrane pressure increase speed selected on the basis of the value of the organic substance concentration measured by the organic substance concentration measurement means, with a transmembrane pressure increase speed calculated from the transmembrane pressure measured by the pressure measurement unit; and a control unit which controls the membrane surface aeration flow amount of the membrane surface aeration device, wherein the control unit changes the membrane surface aeration flow amount on the basis of the difference between the transmembrane pressure increase speeds, obtained by the transmembrane pressure increase speed comparing means.

A method and a system for recycling spent ethylene or propylene glycol recovered from aircraft deicing solutions is described. The recovered spent ethylene or propylene glycol contains water and other undesirable substances which require to be removed to produce a solution free of these substances which can be further processed to remove substantially all of the water content and to blend-in additives required to certify the final glycol solution for aircraft deicing. The method and system employs a computer controller for continuous automatic batch processing of the spent glycol, including, in combination, filtering, distillation, blending and testing in specific sequences and achieves an improved quality recycled glycol of a purity of at least 99.5% and preferably between 99.6% to 99.9% glycol concentration.

A method for managing an operation of a reverse osmosis membrane device, includes managing the operation of the reverse osmosis membrane device based on an aluminum ion concentration and/or an iron ion concentration of a feed water and/or a concentrated water of the reverse osmosis membrane device. Any one or more of suitability of a raw water as the feed water, a water temperature of the feed water, a concentration ratio (recovery rate), a pressure (feed water supply pressure, concentrated water pressure, or treated water pressure of the reverse osmosis membrane), an amount of the concentrated water, a continuous operation period, a washing time, a wash frequency, and a timing of replacement of the reverse osmosis membrane are managed based on the aluminum ion concentration and/or the iron ion concentration of the feed water and/or the concentrated water.

An automated modular filtration system, particularly for low volume tangential flow filtration processes, comprises a plurality of filtration modules formed as separate assemblies and at least one control unit for jointly controlling filtration processes of individual filtration units. Each filtration module contains at least one individual filtration unit for executing a filtration process independent of the other filtration units, first input ports for receiving a first type of fluids, second input ports for receiving a second type of fluids, and exit ports for outputting unused system fluids. First type fluids are process fluids are specific to the filtration processes executed in individual filtration units. Second type fluids are system fluids not specific to filtration processes executed in the individual filtration units. The second input and exit ports establish inter-module connections so system fluids can be forwarded from one filtration module to an adjacent filtration module of the filtration system.