A ultrapure water supply system 10 includes a pure water tank 16 provided vertically below a use point 30, a return pipe 32 through which ultrapure water is returned from the use point 30 to the pure water tank 16, a first pressure regulating valve 40 that is provided at a first position H1 of the return pipe 32 and adjusts a first pressure upstream of the first position H1 and a second pressure regulating valve 42 that is provided at a second position H2 downstream of the first position H1 and vertically below the first position H1 of the return pipe 32 and adjusts a second pressure downstream of the first position H1 and upstream of the second position H2.

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.

A process for recovery of lithium ions from a lithium-bearing brine includes contacting the lithium-bearing brine with a lithium ion sieve (where that LIS includes an oxide of titanium or niobium) in a first stirred reactor to form a lithium ion complex with the lithium ion sieve, and decomplexing the lithium ion from the lithium ion sieve in a second stirred reactor to form the lithium ion sieve and an acidic lithium salt eluate.

Per- and polyfluoroalkyl substances (PFAS) are destroyed by oxidation in supercritical conditions. PFAS in water is concentrated in a reverse osmosis step and salt from the resulting solution is removed in supercritical conditions prior to destruction of PFAS in supercritical conditions.

Draw compounds and draw solutions comprising said draw compounds for use in forward osmosis solvent purification systems. The draw compound may be a linear random, sequential, or block molecular chain consisting of at least one oxide monomer or diol monomer and have a temperature-dependent affinity with a feed solvent. The draw compound may further include a first terminal group and a second terminal group, at least one of the first terminal group and the second terminal group selected from the group consisting of a hydroxyl group, an amine group, a carboxylic group, an allyl group, and a C1 to C14 substituted and unsubstituted alky group. The draw compound may also be a branched random, sequential, or block molecular chain consisting of at least one oxide monomer or diol monomer.

The present disclosure provides a physicochemical water treatment process using a microfiber filter coated with a coagulant, including: a) performing a pressurized filtration by supplying raw water to an upper portion of a pressurized microfiber filtering device including a microfiber filter coated with a coagulant; b) backwashing the microfiber filter by supplying backwashing water and air from a lower portion of the microfiber filtering device; and c) after the backwashing of the microfiber filter is completed, coating the microfiber filter with the coagulant by supplying the coagulant together with the backwashing water, wherein backwashing wastewater of the pressurized microfiber filtering device is concentrated by the suction type microfiber filter coated with the coagulant and transferred to a dehydrator.

A method and system is provided for treating waste generated from manufacturing operations including at least one of Printed Circuit Boards Fabrication (PCB FAB), General Metal Finishing (GMF), semiconductors manufacturing, chemical milling, and Physical Vapour Deposition (PVD). The method and system are used to create zero liquid discharge recycling.

The invention relates to a system and method of use for concentrating a solution that is eluted from an ion exchange process (elution solution) during an ion exchange regeneration using the osmotic pressure of the salt saturator. This method recovers solvent from the elution solution that could be used in a future ion exchange regeneration process. The concentration of the elution solution may include the precipitation and removal of solids from the elution solution.

A method and system is provided for treating waste generated from manufacturing operations including at least one of Printed Circuit Boards Fabrication (PCB FAB), General Metal Finishing (GMF), semiconductors manufacturing, chemical milling, and Physical Vapour Deposition (PVD). The method and system are used to create zero liquid discharge recycling.

The disclosure relates to a method for separation and purification of N-acetyl-glucosamine, and belongs to the technical field of biological engineering. In the disclosure, a raw material solution containing N-acetyl-glucosamine is obtained by microbial fermentation or by hydrolyzing the chitin. The raw material solution is subjected to flocculation pretreatment, and continuous centrifugation or pressure filtration is performed to remove suspended solids such as microorganisms, proteins and polysaccharides to obtain clear liquid. Double-stage ion exchange chromatography is performed to remove impurities such as charged organic molecules and inorganic salts. Membrane concentration is performed to efficiently remove water to improve the concentration of the target product. Spray drying or further evaporation concentration and crystallization are performed. Finally drying is performed to obtain an N-acetyl-glucosamine crystal of which the purity is more than 99%.