Dewatering of saline sewage sludge using iron-oxidizing bacteria: Effect of substrate concentration. (August 2016)

• Record Type: Journal Article
• Authors: Wong, Jonathan W.C.; Murugesan, Kumarasamy; Selvam, Ammaiyappan; Ravindran, Balasubramanian; Kurade, Mayur B.; Yu, Shuk-Man
• Is Part Of: Bioresource technology. Volume 213(2016)
• Page Start: 31
• Page End: 38
• Publication Date: 2016-08
• Subjects: Activated sludge -- Anaerobically digested sludge -- Sludge dewaterability -- Acidithiobacillus ferrooxidans -- Biogenic flocculant; Biomass -- Periodicals; Biomass energy -- Periodicals; Bioremediation -- Periodicals; Agricultural wastes -- Periodicals; Factory and trade waste -- Periodicals; Organic wastes -- Periodicals; Bioénergie -- Périodiques; Déchets agricoles -- Périodiques; Déchets industriels -- Périodiques; Déchets organiques -- Périodiques; Déchets (Combustible) -- Périodiques; 662.88
• DOI: 10.1016/j.biortech.2016.03.118
• Languages: English
• ISSNs: 0960-8524

Abstract

Highlights: Acidithiobacillus ferrooxidans is a potential biogenic flocculant producer. Bioacidification and dewaterability of saline sewage sludge was investigated. Optimum dose of Fe 2+ to sludge solids was optimized to improve the dewaterability. Sludge CST and SRF were significantly reduced by biogenic flocculant. Abstract: This study investigated the improvement in dewaterability of activated sludge (ACS) and anaerobically digested sludge (ADS) through bioacidification approach using iron-oxidizing bacterium, Acidithiobacillus ferrooxidans . ACS and ADS were treated with A. ferrooxidans culture with addition of different concentrations of energy substrate, in terms of Fe 2+ :sludge solids ratio (0:1, 0.01:1, 0.05:1 and 0.1:1), and the dewaterability was assessed by determining the capillary suction time (CST), time to filter (TTF) and specific resistance to filtration (SRF) of the sludge. The results revealed that the levels of Fe 2+ significantly influenced the sludge acidification (pH ⩽ 3). The CST, TTF and SRF values rapidly decreased in treated sludge, indicating that dewaterability of the sludge was significantly ( p < 0.05) improved than untreated sludge. This investigation clearly demonstrates that A. ferrooxidans culture, as biogenic flocculant, can be potentially used for improving the sludge flocculation, stabilization and dewaterability.