Next Article in Journal
Influence of Two-Stage Combinations of Constructed Wetlands on the Removal of Antibiotics, Antibiotic Resistance Genes and Nutrients from Goose Wastewater
Next Article in Special Issue
Removal of Tetracycline by Hydrous Ferric Oxide: Adsorption Kinetics, Isotherms, and Mechanism
Previous Article in Journal
The Association Between Health Conditions, Consciousness, Involvement, and Knowledge and Dietary Supplement Intake among University Students in South Korea
Previous Article in Special Issue
Investigation of a Gas Hydrate Dissociation-Energy-Based Quick-Freezing Treatment for Sludge Cell Lysis and Dewatering
Open AccessArticle

Physicochemical and Biological Effects on Activated Sludge Performance and Activity Recovery of Damaged Sludge by Exposure to CeO2 Nanoparticles in Sequencing Batch Reactors

by Qian Feng 1,2,*, Yaqing Sun 2, Yang Wu 2, Zhaoxia Xue 1,2, Jingyang Luo 1,2, Fang Fang 1,2, Chao Li 1,2 and Jiashun Cao 1,2
1
Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, Nanjing 210098, China
2
College of Environment, Hohai University, Nanjing 210098, China
*
Author to whom correspondence should be addressed.
Int. J. Environ. Res. Public Health 2019, 16(20), 4029; https://doi.org/10.3390/ijerph16204029
Received: 13 August 2019 / Revised: 19 September 2019 / Accepted: 2 October 2019 / Published: 21 October 2019
(This article belongs to the Collection Municipal Wastewater Treatment and Sludge Treatment and Disposal)
Recently, the growing release of CeO2 nanoparticles (CeO2 NPs) into sewage systems has attracted great concern. Several studies have extensively explored CeO2 NPs’ potential adverse impacts on wastewater treatment plants; however, the impaired activated sludge recovery potentials have seldom been addressed to date. To explore the physicochemical and biological effects on the activated sludge performance and activity recovery of damaged sludge by exposure to CeO2 NPs in sequencing batch reactors (SBRs), four reactors and multiple indicators including water quality, key enzymes, microbial metabolites, the microbial community structure and toxicity were used. Results showed that 10-week exposure to higher CeO2 NP concentration (1, 10 mg/L) resulted in a sharp decrease in nitrogen and phosphorus removal efficiencies, which were consistent with the tendencies of key enzymes. Meanwhile, CeO2 NPs at concentrations of 0.1, 1, and 10 mg/L decreased the secretion of tightly bound extracellular polymeric substances to 0.13%, 3.14%, and 28.60%, respectively, compared to the control. In addition, two-week recovery period assays revealed that the functional bacteria Proteobacteria, Nitrospirae and Planctomycetes recovered slightly at the phyla level, as analyzed through high-throughput sequencing, which was consistent with the small amount of improvement of the effluent performance of the system. This reflected the small possibility of the activity recovery of damaged sludge. View Full-Text
Keywords: cerium oxide nanoparticles; key enzymes; extracellular polymeric substances; microbial community; activity recovery of damaged sludge cerium oxide nanoparticles; key enzymes; extracellular polymeric substances; microbial community; activity recovery of damaged sludge
Show Figures

Figure 1

MDPI and ACS Style

Feng, Q.; Sun, Y.; Wu, Y.; Xue, Z.; Luo, J.; Fang, F.; Li, C.; Cao, J. Physicochemical and Biological Effects on Activated Sludge Performance and Activity Recovery of Damaged Sludge by Exposure to CeO2 Nanoparticles in Sequencing Batch Reactors. Int. J. Environ. Res. Public Health 2019, 16, 4029.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
  • Supplementary File 1:

    PDF-Document (PDF, 644 KB)

  • Externally hosted supplementary file 1
    Doi: 10.5281/zenodo.3366864
    Link: https://doi.org/10.5281/zenodo.3366864
    Description: Figure Captions Figure S1. The magnified SEM images of the activated sludge from R4. (The yellow circles in Figure S1 a, b, c, d represent the filamentous bacteria, spherical bacteria, rod-shaped bacteria and the attached CeO2 NPs, respectively.) Figure S2. Relative LDH release during one cycle after 1-d and 10-week exposure to CeO2 NPs at different concentrations, respectively. Error bars represent standard deviations of triplicate measurement. Figure S3. The energy spectrum of activated sludge within 2-week recovery time relieved from the 10-week exposure to 0.1 (a), 1 (b), and 10 (c) mg/L CeO2 NPs. Figure S4. Heat-map of the four reactors within 2-week recovery time relieved from the 10-week exposure to different CeO2 NPs concentration
Back to TopTop