Treatment and optimization of high-strength egg-wash wastewater effluent using electrocoagulation and electrooxidation methods

Pankaj Bhatt; Bernard A Engel; Karthik B Shivaram; Ronald F Turco; Zhi Zhou; Halis Simsek

doi:10.1016/j.chemosphere.2023.140632

Treatment and optimization of high-strength egg-wash wastewater effluent using electrocoagulation and electrooxidation methods

Chemosphere. 2024 Jan:347:140632. doi: 10.1016/j.chemosphere.2023.140632. Epub 2023 Nov 13.

Authors

Pankaj Bhatt¹, Bernard A Engel¹, Karthik B Shivaram¹, Ronald F Turco², Zhi Zhou³, Halis Simsek⁴

Affiliations

¹ Department of Agricultural & Biological Engineering, Purdue University, West Lafayette, IN, USA.
² Department of Agronomy, Purdue University, West Lafayette, IN, USA.
³ School of Civil Engineering, Purdue University, West Lafayette, IN, USA; Division of Environmental & Ecological Engineering, Purdue University, West Lafayette, IN, USA.
⁴ Department of Agricultural & Biological Engineering, Purdue University, West Lafayette, IN, USA. Electronic address: simsek@purdue.edu.

PMID: 37967677
DOI: 10.1016/j.chemosphere.2023.140632

Abstract

Egg-washing wastewater contains a high concentration of nutrition and organic matter since eggs are broken during the washing and cleaning processes. Moreover, the wastewater contains small amounts of detergents or sanitizing agents. These contaminants may pose environmental challenges when they are not properly managed or treated. The study scrutinizes the efficiency of electrocoagulation (EO) and electrooxidation (EO) approaches for egg-wash wastewater treatment. The response surface methodology was employed to optimize the operational parameters. The removal efficiencies of soluble chemical oxygen demand (sCOD 90%), ammonia (NH₃-N 91%), nitrate (NO₃^--N 97%), nitrite (NO₂^--N 89.3%), total dissolved nitrogen (TDN 91%), and phosphate (90%) were measured under various treatment conditions. The optimum treatment conditions achieved in the combined EC + EO process were pH 6.0, current density 20 mA cm^-2, and electrolysis time of 60 min, respectively. Degradation kinetics of the egg-wash pollutants showed a significant reduction in half-life (t_1/2) with EO (after EC-Aluminum) at 15 min, 12 min, 17 min, and 15 min for sCOD, NO₂^--N. NO₃^--N, and TDN, respectively. Whereas the half-life of NH₃-N (18 min) and phosphate (17 min) reduced significantly with the EO (after EC-iron). Al and Fe electrodes coupled with boron-doped diamond were found efficient for pollutant removal. Environmental implication. Egg-wash wastewater has a high protein content and contains nutrients that are essential for living organisms. While these compounds can be valuable for agricultural use by increasing soil phosphate concentration, they can also become an issue if the excess nutrients are not properly managed. The soil has a threshold limit for holding phosphate, and any excess amount may be transported through surface runoff or contaminate groundwater through leachate, potentially affecting aquatic ecosystems and water quality. This study explores the efficiency of electrocoagulation and electrooxidation methods in treating egg-wash wastewater. These methods aim to remove pollutants and reduce their environmental impact.

Keywords: Egg-wash; Electrochemical treatment; Environment; Pollution; Wastewater.

MeSH terms

Ecosystem
Electrocoagulation / methods
Electrodes
Environmental Pollutants*
Nitrogen Dioxide
Phosphates
Soil
Waste Disposal, Fluid / methods
Wastewater
Water Pollutants, Chemical* / chemistry

Substances

Wastewater
Nitrogen Dioxide
Environmental Pollutants
Soil
Phosphates
Water Pollutants, Chemical