These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: In situ generation of zero valent iron for enhanced hydroxyl radical oxidation in an electrooxidation system for sewage sludge dewatering.
    Author: Hu S, Hu J, Liu B, Wang D, Wu L, Xiao K, Liang S, Hou H, Yang J.
    Journal: Water Res; 2018 Nov 15; 145():162-171. PubMed ID: 30142514.
    Abstract:
    A hybrid electrochemical conditioning strategy for enhanced sewage sludge dewatering was proposed. A water content of 47.2 wt.% for the dewatered sludge cake was achieved at an applied voltage of 20 V for 30 min, which was significantly lower than previously reported results. The capillary suction time (CST) and specific resistance to filtration (SRF) were decreased by 75.6% and 90.9%, respectively. Four simultaneous processes, including electrooxidation, the electro-Fenton process, molecular oxygen activation via zero valent iron (ZVI) and Fe(III) flocculation, had synergetic effects on the degradation of extracellular polymeric substances (EPS) to enhance sludge dewaterability. The in situ generation of ZVI on the cathode electrode facilitated the reduction of Fe(III) to Fe(II) via activation of molecular oxygen. The sludge pH decreased spontaneously and remained acidic due to the competitive reaction of ZVI generation to hydrogen evolution as well as the Fe(III) flocculation process, which further guaranteed the high efficiency of hydroxyl radical generation. Changes in the physiochemical properties of the sludge (particle size distribution, zeta potential, viscosity and EPS characteristics) induced by the hybrid conditioning process were further explored. In addition, the economic potential of the hybrid system was preliminarily assessed (USD$ 127.6/ton dry sludge).
    [Abstract] [Full Text] [Related] [New Search]