Nanofiltration

In nanofiltration and reverse osmosis membrane systems 75–90% of the feed water is conversed to product, and as a consequence dissolved compounds are concentrated in the membrane concentrate. Subsequently, sparingly soluble inorganic compounds such as calcium carbonate and barium sulphate become sup

It is imperative to review the history of the past to provide a vision for the future. It is therefore the objective of this paper to review the history of the development of membranes and membrane processes for water production in general and seawater desalination in particular. The review highligh

Very severe troubles of scale formation might be expected when the recovery of water from seawater increases. The main constituents of the scale are CaCO3, Mg(OH)2 and CaSO4, all of which are salts of alkaline earth metals. Therefore, if a key technology will be developed by which the main constitue

Irvine Ranch Water District (IRWD) is located in the heart of Orange County in Southern California. 1RWD provides water to and Ireats wastewater for more than 130,000 people. IRWD is now developing the Deep Aquifer Treatment System (DATS), which consists of an 8 mgd (30,000 cmd) membrane plant for r

Membrane fouling may be dissected into four types: complete pore blocking, incomplete pore blocking, standard pore blocking and external surface fouling (cake/gel deposition). Using our experimental data on nanofiltration (NF) of NaCl solutions containing biosodiummethylene-bis-naphthalene sulphonat

For the last 3 years, the SWCC–RDC conducted extensive R&D work on nanofiltration (NF) pretreatment of feed to SWRO and make-up to MSF pilot plants in dihybrid arrangement of NF–SWRO or NF–MSF, also in trihybrid of NF–SWROreject–MSF, where the SWROreject from the dihybrid NF–SWRO is used as make-up

Integrated membrane systems (IMS) were pilot tested for treatment of a high TOC river water. Pretreatment methods included microfiltration, in-line coagulation–microfiltration, and coagulation–sedimentation–filtration. Fouling was minimized at lower flux, lower recovery and with the addition of a bi

Most of volatile organohalide compounds (HOVs) present in surface waters and ground waters are carcinogenic. In drinking water, they represent a danger for human health and are present in water resources. The objective of this study was to characterize the performances of nanofiltration as a refinin

Scaling in reverse osmosis (RO) and nanofiltration (NF) systems is generally controlled by limiting the conversion and/or the addition of antiscalants. An alternative approach might be the desupersaturation of membrane concentrate before e.g. the last stage of an RO and/or NF system. A desupersatura