Loading patent…
AssigneeIonics, Incorporated
InventorsIrving D. Elyanow, Arthur L. Goldstein, Russell J. MacDonald, Wayne A. McRae, Keith J. Sims, Li Zhang
Estimating the term…
Electrodialysis ("ED") stacks are disclosed having components selected from the group: a) cation exchange ("CX") membranes and/or CX granules having in at least a surface a predominant amount of sulfonate exchange groups and a minor amount of weakly ionized exchange groups; b) anion exchange ("AX") membranes and/or AX granules having in at least a surface substantially only quaternary ammonium and/or phosphonium exchange groups which upon decomposition leave almost no amine or phosphine groups bound to the membranes or granules; c) AX and/or CX granules which are selective to monovalent ions at currents which are fractions of the limiting current of such granules; d) AX and/or CX membranes and granules, such membranes and granules selective to monovalent ions at currents which are fractions of the limiting current of such membranes and granules; e) ion exchange ("IX") granules in which the concentration of IX groups in the inner regions is a fraction (including zero) of the concentration in the outer regions; f) AX membranes and/or granules having in at least a surface AX groups having the formula ##STR1## where the R's represent substituents other than hydroxyethyl having at least two carbon atoms, at least one of the R's represents the polymeric structure of such membranes or granules, or a connection thereto, where two or more R's may represent ring structures and A represents nitrogen or phosphorus. Also disclosed are processes for softening, de-nitrating, de-silicizing or demineralizing water or for removing ash from milk products.
An electrodialysis stack comprising one or more components selected from the group consisting of:
An electrodialysis apparatus comprising first and second dilute compartments, said first dilute compartments comprising:
An electrodialysis apparatus comprising first and second dilute compartments, said first dilute compartments containing ion exchange granules comprising in part anion exchange granules which are selective to nitrate and/or chloride ions compared to sulfate ions in dilute solutions during electrodialysis at current densities substantially less than the limiting current density of said anion exchange granules in said first dilute compartments, said second dilute compartments containing as a packing anion exchange granules and cation exchange granules, said apparatus further comprising means for conveying effluent from said first dilute compartments to said second dilute compartments.
A demineralization apparatus comprising means for removing at least part of any colloidal matter from a liquid, means for conveying liquid from which at least part of any colloidal matter has been removed to the first dilute compartments of an electrodialysis apparatus having first and second dilute compartments, said first dilute compartments containing ion exchange granules comprising in part anion exchange granules which are selective to nitrate and/or chloride ions compared to sulfate ions in dilute solutions during electrodialysis at current densities substantially less than the limiting current density of said anion exchange granules in said first dilute compartments, said second dilute compartments comprising anion exchange granules and cation exchange granules, said apparatus further comprising means for conveying effluent from said first dilute compartments to said second dilute compartments.
A demineralization apparatus comprising means for removing at least part of any colloid matter from a liquid, said means selected from the group consisting of means for sorbing colloid matter, means for filtering out colloid matter, microfiltration means, ultrafiltration means, nanofiltration means and reverse osmosis means, said apparatus also comprising means for conveying liquid from which at least part of any colloid matter has been removed to at least the dilute compartments of an electrodialysis apparatus, said dilute compartments containing ion exchange granules comprising at least in part anion exchange granules which are selective to nitrate and/or chloride ions compared to sulfate ions in dilute solutions during electrodialysis at current densities substantially less than the limiting current density of said anion exchange granules in said dilute compartments.
A demineralization apparatus comprising means for removing at least part of any colloid matter from a liquid, said means selected from the group consisting of means for sorbing colloidal matter, means for filtering out colloid matter, microfiltration means, ultrafiltration means, nanofiltration means, and reverse osmosis means, means for conveying liquid from which at least part of any colloid matter has been removed to at least dilute compartments of an electrodialysis apparatus, said dilute compartments containing ion exchange granules comprising at least in part cation exchange granules which are selective to sodium ions compared to calcium ions in dilute solutions during electrodialysis at current densities substantially less than the limiting current density of said cation exchange granules in said dilute compartments.
A demineralization apparatus comprising means for removing at least part of any colloid matter from a liquid, means for conveying liquid from which at least part of any colloid matter has been removed at least to at least partly filled compartments of an electrodialysis apparatus, said at least partly filled compartments containing as filling ion exchange granules comprising at least in part monovalent-ion-selective ion exchange granules which are selective to monovalent ions compared to divalent ions of the same charge sign in dilute solutions during electrodialysis at current densities substantially less than the limiting current density of said monovalent-ion-selective granules in said at least partly filled compartments.
A demineralization apparatus comprising:
Apparatus for removing silica from aqueous liquid having a pH substantially less than about 9, said apparatus comprising:
Apparatus for demineralizing aqueous liquid said apparatus comprising:
Apparatus for removing silica from an aqueous liquid, said apparatus comprising:
Apparatus for removing silica from an aqueous liquid, said apparatus comprising:
Apparatus for removing silica and other minerals from an aqueous liquid, said apparatus comprising:
Apparatus for demineralizing and desilicizing aqueous liquid, said apparatus comprising:
Apparatus for demineralizing and desilicizing aqueous liquid which has a pH substantially less than about 9 and an electrical conductivity less than about 10 micro-Siemens/cm, said apparatus comprising:
A reversing or non-reversing electrodialysis stack comprising cation exchange membranes which comprise as exchange groups, in at least the surface portions of said membranes which surface portions contact fluid in the diluting compartments of said stack, a predominant amount of sulfonic acid moieties and a minor amount of weakly acid and/or weakly basic moieties or both weakly acid moieties and weakly basic moieties.
A reversing or non-reversing electrodialysis stack comprising anion exchange membranes having as anion exchange groups, in at least those surface portions of said membranes which contact the fluid in diluting compartments of said stack, substantially only quaternary ammonium and/or phosphonium groups and substantially no primary, secondary and/or tertiary amine and/or phosphine groups and in which decomposition of said ammonium and/or phosphonium groups during electrodialysis leaves in the said surface portions substantially no primary, secondary and/or tertiary amine and/or phosphine groups bound to said membranes, said stack optionally containing ion exchange granules.
A reversing or non-reversing electrodialysis stack comprising:
Dependencies are inferred from the claim text.