Dewaterability of Excess Activated Sludge with Fly Ash Conditioning

Abstract:

The coal fly ash (CFA)/coal fly ash modified by sulfuric acid (MCFA)-conditioned sludge dewaterability was investigated in this study. Specific resistance of filtration (SRF) was used to assess the sludge dewaterability. Extracellular polymeric substance (EPS) was determined in attempt to explain sludge conditioning process. The results showed that SRF of the sludge significantly decreased with coal fly ash addition, and the MCFA showed much stronger conditioning capacity than the raw coal fly ash. Under a MCFA dosage of 36g.L^-1, the SRF of the sludge decreased from 1.18×10¹² to 6.47×10¹⁰ m.kg¹, and EPS concentration of the sludge decreased from 32.64 to 17.55mg.L^-1. The sludge conditioning mechanisms with MCFA mainly included improving adsorption bridging and providing the water transmitting passages by skeleton builder.

• Periodical: Advanced Materials Research (Volumes 726-731)
• Pages: 2651-2654
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.726-731.2651
• Online since: August 2013
• Authors: Chang Nian Wu, Wei Hua Li, Qi Ling, Li Wang, Fa Kang Pan, Yi Tang, Yang Li
• Keywords: Coal Fly Ash, Dewaterability, Modification, Sludge

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