Record Display for the EPA National Library Catalog


OLS Field Name OLS Field Data
Main Title Activated Silica in Wastewater Coagulation.
Author Weber, Jr., W. J. ; Ketchum, Jr., L. H. ;
CORP Author Michigan Univ., Ann Arbor. Coll. of Engineering.
Year Published 1974
Report Number EPA-17030-DUW; W74-07738 ; EPA-670/2-74-047
Stock Number PB-232 454
Additional Subjects Coagulation ; Calcium oxides ; Sewage treatment ; Sewage treatment ; Silicon dioxide ; Alkalinity ; Performance evaluation ; Cost estimates ; Waste water ; Activated silica
Library Call Number Additional Info Location Last
NTIS  PB-232 454 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. 06/23/1988
Collation 168p
The role of activated silica in coagulation of wastewaters with lime was examined. Laboratory studies were conducted on synthetic wastewaters to simulate certain wastewater characteristics and verification studies were conducted on samples of natural waters and wastewaters. For high alkalinity wastewaters activated silica provides no substantial benefit; reasons for the loss of effectiveness are discussed. For low alkalinity wastewaters however, significant (3 to 10-fold) reduction in lime requirement is possible; the addition necessary to accomplish this lime reduction is small, 2 to 4 mg/l as SiO2. In low alkalinity wastewaters high in phosphate concentration (approximately 7 mg/l as PO4) coagulation is accomplished with low lime addition only; multinuclear silica is as effective and in most cases more effective than activated silica. This treatment scheme may provide a convenient method of treating storm and combined sewer discharges which are commonly low in alkalinity.