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Published on: October 15, 2015
Valuation of OSA process and folic acid addition as excess sludge minimization alternatives applied in the activated
C L Martins1, V F Velho1, S R A Ramos1
1Department of Sanitary and Environmental Engineering - UFSC/CTC/ENS, Campus Universitário - Trindade, Florianópolis, SC 88.010-970, Brazil
Abstract:
The aim of this study was to investigate the ability of the oxic-settling-anaerobic (OSA)-process and the folic acid addition applied in the activated sludge process to reduce the excess sludge production. The study was monitored during two distinct periods: activated sludge system with OSA-process, and activated sludge system with folic acid addition. The observed sludge yields (Yobs) were 0.30 and 0.08 kgTSS kg(-1) chemical oxygen demand (COD), control phase and OSA-process (period 1); 0.33 and 0.18 kgTSS kg(-1) COD, control phase and folic acid addition (period 2). The Yobs decreased by 73 and 45% in phases with the OSA-process and folic acid addition, respectively, compared with the control phases. The sludge minimization alternatives result in a decrease in excess sludge production, without negatively affecting the performance of the effluent treatment.
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