A system and method for producing from saline source water a product containing an increased ratio of multi-valent ions to mono-valent ions, which includes multiple nanofiltration units arranged to selectively remove mono-valent ions from the water fed into each nanofiltration stage in the nanofiltration permeate stream while retaining multi-valent ions in the nanofiltration reject stream. The rate at which the increase in the multi-valent ion- to mono-valent ion ratio is obtained may be enhanced by introduction of lower salinity water into the nanofiltration reject between stages, and by recirculating a portion of downstream nanofiltration reject flow into an upstream nanofiltration unit. The enhanced multi-valent ion product is suitable for multiple uses, including irrigation of plants and remineralization of desalinated water. The relative concentrations of the multi-valent ions in the product may be adjusted, for example by selection of nanofiltration membrane technologies which have higher or lower rejection for specific multi-valent ions.

A process to remove nitrates and chrome from water. The process includes the steps of passing incoming nitrate and chrome contaminated water through a nanofiltration membrane. Retentate liquid rejected from the nanofiltration membrane is pumped to effluent or returned to the nanofiltration membrane. Permeate from the nanofiltration membrane is sprayed through a well screen upper collector above an open atmospheric bed having strong base ion exchange resin. The permeate is pumped through the ion exchange resin and through a gravel layer beneath the resin. The strong base ion exchange resin is periodically regenerated.

A system and method for producing from saline source water a product containing an increased ratio of multi-valent ions to mono-valent ions, which includes multiple nanofiltration units arranged to selectively remove mono-valent ions from the water fed into each nanofiltration stage in the nanofiltration permeate stream while retaining multi-valent ions in the nanofiltration reject stream. The rate at which the increase in the multi-valent ion to mono-valent ion ratio is obtained may be enhanced by introduction of lower salinity water into the nanofiltration reject between stages, and by recirculating a portion of downstream nanofiltration reject flow into an upstream nanofiltration unit. The enhanced multi-valent ion product is suitable for multiple uses, including irrigation of plants and remineralization of desalinated water. The relative concentrations of the multi-valent ions in the product may be adjusted, for example by selection of nanofiltration membrane technologies which have higher or lower rejection for specific multi-valent ions.

Disclosed is a natural compound sweetener, comprising mogroside V, rebaudioside A, natural tea theanine and dietary fibre. The method for preparing the sweetener comprises the steps of: (1) dissolution, filtration, concentration and sterilization: dissolving the mogroside V, rebaudioside A, natural tea theanine and dietary fibre in water, filtering, concentrating in a vacuum, and sterilizing to obtain a sterilized solution; and (2) paste-collection, drying and granulation: carrying out paste-collection on the sterilized solution obtained in the step (1), vacuum drying the collected liquid paste, and drying and then granulating the dry powder to obtain the sweetener.

Embodiments disclosed herein are directed to methods and systems for treating wastewater via forward osmosis. By way of example, the methods and systems disclosed herein may be used to filter one or more precipitated salts and/or other particles from wastewater generated by power plants such as flue gas wastewater, oil and gas wastewater, and other industrial processes. For example, the methods and systems disclosed herein may be used to filter one or more precipitated salts from a wastewater feed concentrate formed during the forward osmosis process that is recirculated through at least one membrane module to continue the forward osmosis process. Filtering the one or more precipitated salts from the wastewater feed concentrate helps limit clogging of open channel feed spacer(s) of the at least one membrane module.

Processes and systems for filtering a liquid sample are provided. Batches of a liquid sample can be routed to two or more cycling tanks (e.g., first and second cycling tanks). Upon filling a first cycling tank, a first batch of the liquid sample can be routed to a filtration assembly by a continuous diafiltration process that includes routing produced retentate back to the first cycling tank or to a collection vessel. Upon filling a second cycling tank, a second batch of the liquid sample is routed to the filtration assembly by a continuous diafiltration process that includes routing produced retentate back to the second cycling tank or to the collection vessel. The filling and continuous diafiltration of batches of the liquid sample continues to alternate between the two or more cycling tanks until a total product volume is processed.

A direct water purifier comprises: a first filter for filtering water flowing in through a first flow path; a second filter receiving, through a second flow path, and filtering the water filtered by the first filter; a first valve, provided on the second flow path; a pump, provided on the second flow path, for supplying, to the second filter, water at a water pressure equal to or greater than a preset water pressure; a third filter receiving, through a third flow path, and filtering the water filtered by the second filter; a second valve, provided on the third flow path, for decreasing a pressure in the flow path; a third valve, provided at a rear end of the second valve, for preventing a backflow of the water; and a heating unit receiving the water filtered by the third filter and heating the water to a preset temperature.

A direct water purifier comprises: a first filter for filtering water flowing in through a first flow path; a second filter receiving, through a second flow path, and filtering the water filtered by the first filter; a first valve, provided on the second flow path; a pump, provided on the second flow path, for supplying, to the second filter, water at a water pressure equal to or greater than a preset water pressure; a third filter receiving, through a third flow path, and filtering the water filtered by the second filter; a second valve, provided on the third flow path, for decreasing a pressure in the flow path; a third valve, provided at a rear end of the second valve, for preventing a backflow of the water; and a heating unit receiving the water filtered by the third filter and heating the water to a preset temperature.

This invention relates to various membrane-based processes and their combinations, such as Forward Osmosis (FO), Reverse 5 Osmosis (RO), Nanofiltration (NF), Ultrafiltration (UF), Membrane Bioreactor (MBR), Osmotic Distillation (OD) and Membrane Distillation (MD), for various application of dilution, concentration, dewatering, separation, purification, fractionation or extraction applications of different solvents including 10 various sources of water, wastewater, active pharmaceutical ingredients (APIs), food and beverage sources, dairy products etc. It is also applicable to all the industrial and domestic applications that involves recovering or water reclamation from inlet sources.

Liquid solution concentration systems, and related methods, are generally described. In some embodiments, the system is an osmotic system comprising a plurality of osmotic modules. For example, the osmotic system can comprise a feed osmotic module configured to produce an osmotic module retentate outlet stream having a higher concentration of solute than the retentate inlet stream transported to the feed osmotic module. The osmotic system can also comprise an isolation osmotic module fluidically connected to the feed osmotic module. The osmotic system can also optionally comprise a purification osmotic module fluidically connected to the feed osmotic module and/or the isolation osmotic module. Certain embodiments are related to altering the degree to which the feed osmotic module retentate outlet stream is recycled back to the retentate-side inlet of the feed osmotic module during operation. Additional embodiments are related to the manner in which the retentate-side effluent from the isolation osmotic module is distributed among the system modules during operation.