A method includes supplying a supersaturated brine stream having a plurality of minerals and anti-scalant from a water treatment system to a gypsum removal system disposed within a mineral removal system. The gypsum removal system includes a gypsum reactor that may receive the supersaturated brine, may deactivate the anti-scalant such that gypsum precipitates from the supersaturated brine, and may generate a gypsum slurry having a mixture of desupersaturated brine, precipitated gypsum, and the anti-scalant in solution with the desupersaturated brine. The method also includes supplying gypsum seed crystals to the gypsum reactor. The gypsum seed crystals may precipitate the gypsum from the supersaturated brine to generate the gypsum slurry. The method also includes directing a first portion of the gypsum slurry from the gypsum reactor to a gypsum settler. The gypsum settler may reactivate the anti-scalant such that the anti-scalant absorbs onto the precipitated gypsum to remove the anti-scalant from the desupersaturated brine and may generate anti-scalant-gypsum crystals and a desupersaturated overflow having at least a portion of the plurality of minerals. The method further includes generating the gypsum seed crystals supplied to the gypsum reactor using the anti-scalant-gypsum crystals.

A method for preparing agricultural products from a biological sludge containing microbial cells includes the steps of: subjecting the biological sludge to a pretreatment process which includes introducing ozone and supplying a hydraulic pressure to generate cavitation to destroy cell wall of the microbial cells; and subjecting the pretreated biological sludge to a solid-liquid separation treatment to obtain a solid fraction including cell debris and a liquid fraction including a cell lysate solution.

The invention provides methods and compositions for reducing the amount of water required in an industrial process, especially a bottling process such as beer or beverage manufacturing. The method comprising the steps of: collecting water used to rinse cleaned and/or dirty recycled bottles, spraying the collected water at a food contacting piece of equipment as part of a CIP rinse, and passing the CIP second rinse water into a cooling tower as make-up water. The method allows for the re-use of water already in the system but by being careful where each water stream goes the water does not accumulate contaminants that would damage the cooling tower or foul the bottled product or vessel that is cleaned by CIP method.

A method for making a titania-polymer nanocomposite by simultaneously forming TiO.sub.2 nanoparticles in situ from a TiO.sub.2 precursor in the presence of urea and interfacially polymerizing polyamide precursors thereby producing a titania-polymer nanocomposite. A titania-polymer nanocomposite made by this method. A method for removing a dye or metal from water comprising contacting contaminated water with the titania-polymer nanocomposite.

Water treatment systems including electrically-driven and pressure-driven separation apparatus configured to produce a first treated water suitable for use as irrigation water and a second treated water suitable for use as potable water from brackish or saline water and methods of operation of same.

A metal surface treatment liquid recycling system includes a treatment liquid collecting tank, a pre-treatment device, a nanofiltration device and a vacuum distillation device, all of which are connected sequentially. The nanofiltration device includes a feed tank, a first-stage nanofiltration membrane unit, and a second-stage nanofiltration membrane unit. Treatment wastewater in the treatment liquid collecting tank is fed into the pre-treatment device to filter out suspended solids and then enter the feed tank. The wastewater in the feed tank is filtered by the first-stage nanofiltration membrane unit and transformed to a first-stage concentrated waste liquid and first-stage infiltration fluids. The first-stage infiltration fluids are fed into and re-filtered by the second-stage nanofiltration membrane unit and transformed to a second-stage concentrated waste liquid and second-stage infiltration fluids. The second-stage infiltration fluids are evaporated and concentrated by the vacuum distillation device for generation of distilled water and high-concentration acid concentrated fluids.

A system and method for increasing the efficiency of a multi-pass nanofiltration system associated with water desalination and mineral extraction. A saline source water is preferably subjected to a first treatment by passage through a first nanofiltration unit, followed by a second treatment by passage through a second nanofiltration unit. At least a portion of the second nanofiltration unit's reject stream is recirculated to the inlet of the first nanofiltration unit, thereby increasing the production of permeate from the first nanofiltration unit, as well as increasing the purity of monovalent ions in the first nanofiltration unit permeate. Further nanofiltration units with one or more recirculated reject streams may be connected in series and/or in parallel with the first and second nanofiltration units.

A method is provided herein for using produced water (PW), for example, for use in a fracturing fluid. The method includes performing ultrafiltration on the PW to form filtered PW, filtering seawater (SW) to form filtered SW, and blending the filtered PW with the filtered SW to form an aqueous blend.

A water purification system includes: a composite filter cartridge including a pretreatment filter cartridge and a filter membrane assembly; a raw water inlet pipe; a pure water outlet pipe; a pretreated water pipe; a booster pump; a water quality detecting device disposed to the raw water inlet pipe and/or the pure water outlet pipe and configured to detect water quality in the raw water inlet pipe and the pure water outlet pipe; and a control device connected to the water quality detecting device and configured to determine service life of the composite filter cartridge and/or judge whether the composite filter cartridge has lost efficacy according to information detected by the water quality detecting device.

This specification describes membrane based filtration and softening systems and methods. A system has a microfiltration or ultrafiltration (MF/UF) membrane unit upstream of a nanofiltration or reverse osmosis (NF/RO) membrane unit, optionally with no intermediate tank. In some cases, the system and method may be used with feed water provided at municipal line pressure to the membranes. NF/RO permeate is collected in a tank and then pumped to a header. Treated water may be drawn from the header for use or recycled to the system, for example to backwash or flush one or both of the membrane units. In a combined process, NF/RO permeate flushes the feed side of the NF/RO unit and then backwashes the MF/UF unit. In another process, the MF/UF unit and NF/RO unit are filled with NF/RO permeate before being placed in a standby mode.