As industry continues to develop, the contents of various recalcitrant substances that are not removed by conventional wastewater treatment have increased in modern society. The metal working fluids (MWFs) used in the metal working process contain chemical substances, such as mineral oils, anticorrosive agents, extreme-pressure additives, and stabilizers, as well as high concentrations of organics and ammonia-nitrogen. Accordingly, MWFs are required to develop advanced treatments to conserve hydro-ecological resources. This study investigated the removal efficiency of ammonia nitrogen from MWFs according to operating time, applied voltage, and NaCl concentration using a Ti/IrO2 electrode in a batch-type reactor. The experimental results showed that ammonia-nitrogen removal efficiencies without NaCl were 89% and 92% when voltage was adjusted to 15 and 20 V for 60 min and removal efficiency was 90% at 25 V for 40 min. Removal efficiencies of 10 mM NaCl were 4% and 2% greater than those of not adding NaCl at 15 V for 50 min and 20 V for 30 min.

• 김고은 | Go-Eun Kim
• 장성호 | Seong-Ho Jang Corresponding author
• S.Sivakumar
• 송영채(부산대학교 바이오환경에너지학과) | Young-Chae Song (Department of Bioenvironmental Energy, Pusan National University)
• 이원기(부산대학교 바이오환경에너지학과) | Won- Ki Lee (Department of Bioenvironmental Energy, Pusan National University)
• 정병길(부산대학교 바이오환경에너지학과) | Byung-Gil Jung (Department of Bioenvironmental Energy, Pusan National University)
• 류재용(부산대학교 바이오환경에너지학과) | Jae-Yong Ryu (Department of Bioenvironmental Energy, Pusan National University)