TY - JOUR
T1 - Enhanced Sludge Dewaterability and Pathogen Inactivation by Synergistic Effects of Zero-Valent Iron and Ozonation
AU - Yu, Jiangwei
AU - Xiao, Keke
AU - Yang, Jiakuan
AU - Yu, Wenbo
AU - Pei, Kangyue
AU - Zhu, Yuwei
AU - Wang, Junxiong
AU - Liang, Sha
AU - Hu, Jingping
AU - Hou, Huijie
AU - Liu, Bingchuan
N1 - Publisher Copyright:
© 2018 American Chemical Society.
PY - 2019/1/7
Y1 - 2019/1/7
N2 - In this study, the efficiency of the combined zerovalent iron (ZVI) and ozone (O3) treatment at a pH of 2 (acid-ZVI-O3) for simultaneous improvement of sludge dewaterability and pathogen inactivation was investigated. The results showed that the ozone treatment alone deteriorated sludge dewaterability, while the introduction of acid-ZVI into the ozone treatment could significantly enhance the sludge dewaterability. At the optimal conditions with 30 mg O3 g-1 of total solid (TS) and 63 mg ZVI g-1 of TS at a pH of 2, the capillary suction time of conditioned sludge was 1.63 s L g-1 TS, which was much smaller than those of raw sludge (10.45 s L g-1 TS), the single ozonation treated sludge (16.07 s L g-1 TS), and the acid-ZVI-treated sludge (6.98 s L g-1 TS). The acid-ZVI-O3 treatment promoted the generation of hydroxyl radicals and showed synergistic effects in removing key hydrophilic substances which would deteriorate sludge dewaterability, i.e., humic acid-like compounds and soluble microbial byproduct-like substances in the tightly bound extracellular polymeric substances (TB-EPSs). Ferric iron was generated therein and worked as a coagulant to agglomerate sludge particles. The enhanced sludge dewaterability was further confirmed by a laboratory-scale diaphragm filter press. Moreover, the acid-ZVI-O3 treatment showed an effective inactivation of pathogens, which was below the limit specified for class A biosolids, according to the US EPA standard. As such, enhanced sludge dewaterability and pathogen inactivation can be simultaneously achieved with the acid-ZVI-O3 treatment.
AB - In this study, the efficiency of the combined zerovalent iron (ZVI) and ozone (O3) treatment at a pH of 2 (acid-ZVI-O3) for simultaneous improvement of sludge dewaterability and pathogen inactivation was investigated. The results showed that the ozone treatment alone deteriorated sludge dewaterability, while the introduction of acid-ZVI into the ozone treatment could significantly enhance the sludge dewaterability. At the optimal conditions with 30 mg O3 g-1 of total solid (TS) and 63 mg ZVI g-1 of TS at a pH of 2, the capillary suction time of conditioned sludge was 1.63 s L g-1 TS, which was much smaller than those of raw sludge (10.45 s L g-1 TS), the single ozonation treated sludge (16.07 s L g-1 TS), and the acid-ZVI-treated sludge (6.98 s L g-1 TS). The acid-ZVI-O3 treatment promoted the generation of hydroxyl radicals and showed synergistic effects in removing key hydrophilic substances which would deteriorate sludge dewaterability, i.e., humic acid-like compounds and soluble microbial byproduct-like substances in the tightly bound extracellular polymeric substances (TB-EPSs). Ferric iron was generated therein and worked as a coagulant to agglomerate sludge particles. The enhanced sludge dewaterability was further confirmed by a laboratory-scale diaphragm filter press. Moreover, the acid-ZVI-O3 treatment showed an effective inactivation of pathogens, which was below the limit specified for class A biosolids, according to the US EPA standard. As such, enhanced sludge dewaterability and pathogen inactivation can be simultaneously achieved with the acid-ZVI-O3 treatment.
KW - Acid-ZVI-O conditioning
KW - Hydroxyl radicals
KW - Pathogen inactivation
KW - Sludge dewaterability
KW - Waste activated sludge
UR - http://www.scopus.com/inward/record.url?scp=85057554470&partnerID=8YFLogxK
U2 - 10.1021/acssuschemeng.8b03605
DO - 10.1021/acssuschemeng.8b03605
M3 - 文章
AN - SCOPUS:85057554470
SN - 2168-0485
VL - 7
SP - 324
EP - 331
JO - ACS Sustainable Chemistry and Engineering
JF - ACS Sustainable Chemistry and Engineering
IS - 1
ER -
