Reverse osmosis boiler feed water

Reverse osmosis desalination plants consisting of 8 long tubular membranes prepared from commercial CA of D.S. 2.5 were set up for supply of drinking water and boiler feed water at two different locations. 

Electrodialysis is now a mature technology, with Ionics remaining the worldwide industry leader except in Japan. Desalting of brackish water and the production of boiler feed water and industrial process water were the main applications until the 1990s, but electrodialysis has since lost market share due to stiff competition from improved reverse osmosis membranes. Beginning in the 1990s,... 

Water supplied to industry has to meet stringent specifications. For example, process water for the chemical and biotechnology industries is routinely purified beyond potable water standards. Boiler feed water for steam generation must contain a minimum of silica. Reverse osmosis units designed specifically for these purposes are in widespread use today. For example, reverse osmosis/distillation hybrid systems have been designed to separate organic liquids. For semiconductor manufacture, reverse osmosis is combined with ultrafiltration, ion exchange, and activated carbon adsorption to produce the extremely clean water required. 

Reverse osmosis continues to be dominated by desalination, that is, by removing salt from water. The substantial range of applications includes seawater, brackish water, and reclamation of municipal waste water. Similar membranes can be used to pretreat boiler feed water, desirable because pretreated water forms scale in boilers more slowly. There... 

A variety of reverse osmosis membrane systems based on cellulose acetate, aromatic polyamides, and other polymers have been tested for their potential applications. Reverse osmosis membrane equipment is available for large-scale operation since the process is widely used for the production of potable water from sea or brackish waters and upstream of ion exchange in the preparation of ultrapure water for steam-generating boilers. In these applications, the feed concentrations may vary from 500 to 40,000 mg/L of dissolved solids. The RO technique can be used at pH values between 3 and 12 and up to 45°C. 

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