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Purification of effluents of acid copper and nickel plating galvanic processes with conventional cation exchange resins: Copper and nickel recovery
158 The principal ion exchange systems are described: reactor water clean-up system; fuel pool water clean-up systems; condensate treatment system; radioactive wastes treatment system; water make-up system. General considerations and possible develoPments of these techniques are illustrated. Experience with ion exchange resins in the condensate treatment system during start-up of the Caorso nuclear power plant is described. Problems, solutions, and comments on operation of other systems are discussed. F.L. Rizzo, A n s a l d o I m p i a n t i , G e n o a , Italy: O u t l o o k a n d Desires of I o n E x c h a n g e R e s i n T e c h n o l o g y D e v e l o p m e n t in the N u c l e a r Field The report outlines how water treatment systems that generate low quantities of solid and liquid wastes are advantageous for the nuclear plant. Besides, it emphasizes what saving could be possible by developing high-temperature resins used in association with special filtration techniques such as magnetic filters.
R. Stortini, A u s i n o / M o n t e d i s o n , Milan, Italy: P u r i f i c a t i o n of E f f l u e n t s of A c i d C o p p e r a n d N i c k e l Plating G a l v a n i c Processes W i t h C o n v e n tional C a t i o n E x c h a n g e Resins: C o p p e r a n d N i c k e l R e c o v e r y The use of cation exchange resins in processing of dynamic rinse waters from acidic copper and nickel electroplating is discussed. Operations are accomplished by isolating the rinse water from each plating process considered. The purpose of this is to obtain by regeneration of the exhausted exchanger pure and concentrated solutions of one metallic ion (Cu 2÷ or Ni 2÷) which, following a slight correction of properties, may be recycled to the main electroplating tank and thus recovered to afford a financial advantage. The formation of slurry and its environmental and financial disadvantages are thus eliminated. The use of weak-acid (carboxylic) and strong-acid (sulphonic) exchangers is compared and their advantages and disadvantages are emphasized. The use of cationic sulphonic exchangers with countercurrent regeneration seems to be more rational in view of production of decationized water which may, after anion exchange, be recycled in deionized form to the washing of electroplated components. J.R. E m m e t t , B r e w o o d , G r e a t Britain: A n i o n R e s i n K i n e t i c s at H i g h F l o w R a t e s A laboratory testing technique has been developed to study the kinetics of various types of anion resins at high flow rates. This information on resin kinetics is particularly relevant to the selection of resins for use in high flow rate condensate polishing plants. The results illustrate the importance of the resin particle size on the exchange kinetics. L. Liberti, R. Pascali, F. Sigon, a n d R. Z a n n o n i , I s t i t u t o di R i c e r c a Sulle A c q u e , Bari, Italy; E n e l - C R T N , Milan, Italy; Officine R e g g i a n e O M I , Reggio, Italy: I o n E x c h a n g e D e s u l f a t i o n of F e e d W a t e r to M S F E v a p o r a t o r s : Full Scale E x p e r i e n c e To improve the performance of MSF desalination plants it is necessary to decrease the sulfate content of the seawater feed in order to avoid scaling of the heat transfer surfaces. The Desulf process, an ion exchange seawater treatment using a weak anionic resin with primary and secondary amino functional groups (then regenerated with blow-down of the plant itself) has been proved. The thermodynamic and kinetic parameters of the resin are discussed as well as the ion exchange mechanism, determined through laboratory experiments. Data from an actual full-scale plant, treating 140 Mg/h of seawater, are also discussed on a theoretical basis to validate the hypothesized theories. Projections of future developments and new plants are presented. F.X. M c G a r v e y , E.W. H a u s e r , a n d S.M. Z i a r k o w s k i , S y b r o n C h e m i c a l Division, B i r m i n g h a m , N J , U.S.A.:
R. Stortini, A u s i n o / M o n t e d i s o n , Milan, Italy: P u r i f i c a t i o n of E f f l u e n t s of A c i d C o p p e r a n d N i c k e l Plating G a l v a n i c Processes W i t h C o n v e n tional C a t i o n E x c h a n g e Resins: C o p p e r a n d N i c k e l R e c o v e r y The use of cation exchange resins in processing of dynamic rinse waters from acidic copper and nickel electroplating is discussed. Operations are accomplished by isolating the rinse water from each plating process considered. The purpose of this is to obtain by regeneration of the exhausted exchanger pure and concentrated solutions of one metallic ion (Cu 2÷ or Ni 2÷) which, following a slight correction of properties, may be recycled to the main electroplating tank and thus recovered to afford a financial advantage. The formation of slurry and its environmental and financial disadvantages are thus eliminated. The use of weak-acid (carboxylic) and strong-acid (sulphonic) exchangers is compared and their advantages and disadvantages are emphasized. The use of cationic sulphonic exchangers with countercurrent regeneration seems to be more rational in view of production of decationized water which may, after anion exchange, be recycled in deionized form to the washing of electroplated components. J.R. E m m e t t , B r e w o o d , G r e a t Britain: A n i o n R e s i n K i n e t i c s at H i g h F l o w R a t e s A laboratory testing technique has been developed to study the kinetics of various types of anion resins at high flow rates. This information on resin kinetics is particularly relevant to the selection of resins for use in high flow rate condensate polishing plants. The results illustrate the importance of the resin particle size on the exchange kinetics. L. Liberti, R. Pascali, F. Sigon, a n d R. Z a n n o n i , I s t i t u t o di R i c e r c a Sulle A c q u e , Bari, Italy; E n e l - C R T N , Milan, Italy; Officine R e g g i a n e O M I , Reggio, Italy: I o n E x c h a n g e D e s u l f a t i o n of F e e d W a t e r to M S F E v a p o r a t o r s : Full Scale E x p e r i e n c e To improve the performance of MSF desalination plants it is necessary to decrease the sulfate content of the seawater feed in order to avoid scaling of the heat transfer surfaces. The Desulf process, an ion exchange seawater treatment using a weak anionic resin with primary and secondary amino functional groups (then regenerated with blow-down of the plant itself) has been proved. The thermodynamic and kinetic parameters of the resin are discussed as well as the ion exchange mechanism, determined through laboratory experiments. Data from an actual full-scale plant, treating 140 Mg/h of seawater, are also discussed on a theoretical basis to validate the hypothesized theories. Projections of future developments and new plants are presented. F.X. M c G a r v e y , E.W. H a u s e r , a n d S.M. Z i a r k o w s k i , S y b r o n C h e m i c a l Division, B i r m i n g h a m , N J , U.S.A.: