Performance evaluation of the electrolysis process for waste sludge stabilization in decentralization practices
Desalination and Water Treatment
Faculty of Agriculture, Science and Technology, Department of Biological Sciences, North-West University, Mafikeng Campus, Private Bag X2046, Mmabatho, South Africa; Department of Civil Engineering, Yeungnam University, Gyungsan, South Korea; Graduate Faculty of Environment, University of Tehran, Tehran, Iran
Abstract: This study was undertaken to evaluate the potential use of electrolysis process for waste sludge stabilization in decentralization practices by focusing on the operating parameters such as sludge composition, detention time, and electric voltage. The laboratory batch scale results show that the sludge extracted from a packed bed biofilm reactor can reach the minimum concentration of 659 mg/L volatile suspended solids (VSS) merely within 5 h detention time at an applied voltage of 2 V, whereas the most identical level is obtained from activated sludge by 7 h with 3.6 V. The soluble COD in the supernatant phase of the former process would be increased to 297 mg/L by means of 27% VSS reduction. The economical pre-estimation indicates that electrolysis is more sustainable if stand as a preconditioning stage of biological digestion by 70% capital and operating cost reduction. This configuration can also cause occupying 54% lesser footprint area of aerobic digestion with total average reduction of 56% VSS within 77 h. The biological assay on digested product was also determined with reference to the growth of Phragmites sp. plant. This study recommends the electrolysis-pretreated conditioning waste sludge followed by aerobic digestion incorporating with attached growth biological systems as a valuable process in decentralization. © 2014, © 2014 Balaban Desalination Publications. All rights reserved.