Pathogen Deactivation of Glow Discharge Cold Plasma While Treating Organic and Inorganic Pollutants of Slaughterhouse Wastewater

Abstract

Challenges for better treatment of slaughterhouse wastewater (SWW) stem from too strong organic pollutants as well as the potential existence of various pathogen but conventional biological treatment still has shown its limitation. Using cold plasma, this study investigates the physicochemical deactivation of pathogens while treating organic and inorganic pollutants of slaughterhouse wastewater (SWW). Experiments were conducted by decreasing the hydraulic retention time from 0.16 to 1 L/day to derive the best operating condition based on the performance in the cold plasma oxidation. While operating the continuous plasma process, this study identifies the main mechanisms for nitrogen, phosphorus, and iron removal. The results show that chemical oxygen demand (COD), total nitrogen (TN), and total phosphorus (TP) recorded the removal efficiencies of 78~93, 51~92, and 35~83%, respectively. A slight increase in pH via cold plasma influence total iron (T-Fe) removal up to 93%. Cell counting confirms that bacteria could be removed as much as 98% or more in all the operating conditions tested. Toxicity unit dramatically decreased to less than 1 (~ 96% removal). These results suggest that the cold plasma treatment of SWW might be a viable option to manage organic pollutants, pathogen, and toxicity simultaneously.