Ion exchange water treatment

Owens, Dean L., Practical Principles of Ion Exchange Water Treatment, Tall Oaks Publishing, Inc., Voorhees NJ, 1985. 

S.B. Applebaum, Demineralization by Ion Exchange Water Treatment Chemical Processing of Other Liquids, Academic, NY, ... 

Finally, attitudes are changing in the UK as to how the process industries perceive ownership of ion exchange plant especially for the provision of essential services, such as steam, power, and process water. Serious thought is being given to purchasing services from a plant built, owned, maintained, and operated by others either on or off site. This concept is already well established in the privatized power industry and to extend this practice to include process steam and water is a commercial consideration only. Traditionally, industrial ion exchange water treatment plants are permanently located... 

Chapter 9 covers carbon nanotubes, pillared clays, and polymeric resins. Polymeric resins are in widespread use for ion exchange, water treatment, and analytical chromatography. 

Ion Exchange A special kind of adsorption in which the adsorption of an ionic species is accompanied by the simultaneous desorption of an equivalent charge quantity of other ionic species. Ion exchange is commonly used for removing hardness and other metal ions in water treatment. The ion-exchange media can be arranged to provide a specific selectivity. 

Low Level Waste Treatment. Methods of treatment for radioactive wastes produced in a nuclear power plant include (/) evaporation (qv) of cooling water to yield radioactive sludges, (2) filtration (qv) using ion-exchange (qv) resins, (J) incineration with the release of combustion gases through filters while retaining the radioactively contaminated ashes (see Incinerators), (4) compaction by presses, and (5) solidification in cement (qv) or asphalt (qv) within metal containers. 

A hst of polyol producers is shown in Table 6. Each producer has a varied line of PPO and EOPO copolymers for polyurethane use. Polyols are usually produced in a semibatch mode in stainless steel autoclaves using basic catalysis. Autoclaves in use range from one gallon (3.785 L) size in research faciUties to 20,000 gallon (75.7 m ) commercial vessels. In semibatch operation, starter and catalyst are charged to the reactor and the water formed is removed under vacuum. Sometimes an intermediate is made and stored because a 30—100 dilution of starter with PO would require an extraordinary reactor to provide adequate stirring. PO and/or EO are added continuously until the desired OH No. is reached the reaction is stopped and the catalyst is removed. A uniform addition rate and temperature profile is required to keep unsaturation the same from batch to batch. The KOH catalyst can be removed by absorbent treatment (140), extraction into water (141), neutralization and/or crystallization of the salt (142—147), and ion exchange (148—150). 

Makeup. Makeup treatment depends extensively on the source water. Some steam systems use municipal water as a source. These systems may require dechlorination followed by reverse osmosis (qv) and ion exchange. Other systems use weUwater. In hard water areas, these systems include softening before further purification. Surface waters may require removal of suspended soHds by sedimentation (qv), coagulation, flocculation, and filtration. Calcium may be reduced by precipitation softening or lime softening. Organic contaminants can be removed by absorption on activated carbon. Details of makeup water treatment may be found in many handbooks (22—24) as well as in technical Hterature from water treatment chemical suppHers. 

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