Sulfate and dissolved sulfide variation under low COD/Sulfate ratio in Up-flow Anaerobic Sludge Blanket (UASB) treating domestic wastewater
Keywords:
COD/sulfate, dissolved sulfide, kinetics, sulfate reduction, UASB reactors
Abstract
In this study, the dynamics of sulfate reduction and dissolved sulfide generation (S2-, HS-, H2Saq) in liquid phase was evaluated in an UASB reactor treating domestic wastewater with low COD/Sulfate content. The evaluation in the UASB reactor was performed at three sludge heights (0.25, 1.25, 2.25 taps) and effluent of the reactor. Sulfate reduction was verified in the reactor, with an average reduction of 24 % throughout the experiment period. However, the dissolved sulfide concentration in the reactor was not higher than 5.0 mg Sdiss/L. The kinetic model of first order showed good fit to describe the sulfate reduction under different COD/sulfate ratio, with K1app between 2.94x10-5 s-1 and 1.17x10-5 s-1 with correlation coefficients for data over 91%. The maximum rate to sulfate reduction was 18.0 mg SO42-/L.h-1 and small variation in COD/sulfate ratio promotes a significant change both in sulfate and sulfide concentrations.
Published
27/04/2012
Issue
Section
Papers
Authors maintain the copyrights for their work. However, they grant rights of first publication to Ambiente e Agua - An Interdisciplinary Journal of Applied Science. In compensation, the journal can transfer the copyrights, allowing non-commercial use of the article including the right of sending the article to other data bases or publication media. The journal uses the CC BY 4.0 license"