The role of ozone combined with UVC/H2O2 process for the tertiary treatment of a real slaughterhouse wastewater

Pello Alfonso-Muniozguren; Ana I Gomes; Devendra Saroj; Vítor J P Vilar; Judy Lee

doi:10.1016/j.jenvman.2021.112480

The role of ozone combined with UVC/H₂O₂ process for the tertiary treatment of a real slaughterhouse wastewater

J Environ Manage. 2021 Jul 1:289:112480. doi: 10.1016/j.jenvman.2021.112480. Epub 2021 Apr 2.

Authors

Pello Alfonso-Muniozguren¹, Ana I Gomes², Devendra Saroj³, Vítor J P Vilar⁴, Judy Lee⁵

Affiliations

¹ Chemical and Process Engineering, University of Surrey, Guildford, GU27XH, United Kingdom; Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal.
² Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal.
³ Centre for Environmental Health and Engineering (CEHE), Civil and Environmental Engineering, University of Surrey, Guildford, GU27XH, United Kingdom.
⁴ Laboratory of Separation and Reaction Engineering - Laboratory of Catalysis and Materials (LSRE-LCM), Department of Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465, Porto, Portugal. Electronic address: vilar@fe.up.pt.
⁵ Chemical and Process Engineering, University of Surrey, Guildford, GU27XH, United Kingdom. Electronic address: j.y.lee@surrey.ac.uk.

PMID: 33819652
DOI: 10.1016/j.jenvman.2021.112480

Abstract

The main goal of this work is to evaluate the usage of ozone (O₃) as a pre-treatment or simultaneously combined with UVC/H₂O₂ process for the polishing stage treatment of real bio-treated slaughterhouse wastewater. Two different treatment strategies were tested: i) pre-ozonation of the wastewater followed by an UVC/H₂O₂ process (two-step treatment); ii) simultaneous application of O₃/UVC/H₂O₂ combined process (one-step treatment). For the two-step strategy, the pre-treatment with 30 mg O₃/min for 10 min reduces significantly total suspended solids (TSS), turbidity and colour, reducing light filtering effects and increasing the efficiency of the following UVC/H₂O₂ process. In turn, the one-step treatment strategy (O₃/UVC/H₂O₂) allows a more efficient use of injected O₃ by reducing the amount of O₃ required (from 273 to 189 mg O₃/L_effluent) to achieve similar mineralization levels. The real bio-treated slaughterhouse wastewater treated by O₃/UVC/H₂O₂ process achieved final colour values of 20 Pt/Co, TSS of 35 mg/L and COD of 61 mg O₂/L, allowing its direct discharge into water compartments according to European Council Directive 91/271/EEC.

Keywords: Advanced oxidation processes; Ozonation; Process integration; Slaughterhouse wastewater.

MeSH terms

Abattoirs
Hydrogen Peroxide
Oxidation-Reduction
Ozone*
Wastewater
Water Pollutants, Chemical* / analysis
Water Purification*

Substances

Waste Water
Water Pollutants, Chemical
Ozone
Hydrogen Peroxide