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RECORD NUMBER: 22 OF 28

OLS Field Name OLS Field Data
Main Title Rate of Crystallization of Calcium Sulfate in Sulfite Liquor in the Presence of Seeding (Skorost Kristallizatsii Sulfata Kaltsiya v Sulfitnom Shcheloke v Prisutstvii Zatravki).
Author Sibirtsev, Yu. A. ; Sapotnitskii., S. A. ;
CORP Author Environmental Protection Agency, Research Triangle Park, N.C. Translation Services Section.
Year Published 1970
Report Number EPA-TR-76-115;
Stock Number PB-254 556-T
Additional Subjects Crystallization ; Calcium sulfates ; Solutions ; Supersaturation ; Translations ; USSR ;
Holdings
Library Call Number Additional Info Location Last
Modified
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Status
NTIS  PB-254 556-T Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 06/23/1988
Collation 7p
Abstract
Sulfite liquor, obtained during boiling with acid and containing not only a calcium, but also a mixed calcium-sodium base, after preliminary concentration by evaporation is a supersaturated solution of calcium sulfate. Independently of the degree of replacement of the calcium ion with a sodium ion in boiling acid during the two-step method used in industry involving the neutralization of the liquor by milk of lime and ammonia, the solubility curve of calcium sulfate passes through a minimum corresponding to a pH value of 3.5 for the liquor. Upon introduction of a seeding of gypsum crystal into the calcium sulfite liquor, the supersaturation of the solution may be decreased to a significant degree. The effect of the indicated parameters on the rate of crystallization of calcium sulfate was investigated for sulfite liquors of the Kotlasskiy (calcium base) and the Solikamskiy (calcium-sodium base) cellulose-paper combines.