Record Display for the EPA National Library Catalog

RECORD NUMBER: 97 OF 158

OLS Field Name OLS Field Data
Main Title Operational Control of the Activated Sludge Process. Return Sludge Flow Control.
Author West., Alfred W. ;
CORP Author National Field Investigations Center-Cincinnati, Ohio.
Year Published 1973
Stock Number PB-231 599
Additional Subjects Activated sludge process ; Flow control ; Computation ; Flow rate ; Clarification ; Settling ; Loading ; Load control ; Sewage treatment ;
Holdings
Library Call Number Additional Info Location Last
Modified
Checkout
Status
NTIS  PB-231 599 Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy. NTIS 06/23/1988
Collation 16p
Abstract
The return sludge flow, or more precisely, the clarifier sludge flow which includes both return sludge and excess waste sludge flows, should be adjusted to meet measurable process requirements. Attempts to maintain arbitrary return sludge flow percentages of the wastewater flow will seldom achieve optimum sludge quality and process balance. The results of the one-hour mixed liquor settlometer test, the 15-minute mixed liquor and return sludge centrifuge test, and the final clarifier sludge blanket test reading provide the basic data for simple calculation of the clarifier sludge flow rate needed to maintain or restore process equilibrium.