Evaluation of electrical energy consumption in UV/H2O2 advanced oxidation process for simultaneous removal of NO and SO2

The electrical energy consumption (EEC) in removal of NO by a UV/H2O2 oxidation process was introduced and related to removal efficiency of this gas. The absorption-reaction of NO was conducted in a bubble column reactor in the presence of SO2. The variation in NO removal efficiency was investigated for various process parameters including NO and SO2 inlet concentrations, initial concentration of H2O2 solution and gas flow rate. EEC values were obtained in these different conditions. The removal efficiency was increased from about 22% to 54.7% when H2O2 concentration increased from 0.1 to 1.5 M, while EEC decreased by about 70%. However, further increase in H2O2 concentration, from 1.5 to 2, had no significant effect on NO absorption and EEC. An increase in NO inlet concentration, from 200 to 500 ppm, decreased its removal efficiency by about 10%. However, EEC increased from 2.9 × 10−2 to 3.9 × 10−2 kWh/m3. Results also revealed that the presence of SO2 had negative effect on NO removal percentage and EEC values. Some experiments were conducted to investigate the effect of H2O2 solution pH. The changing of pH of oxidation-absorption medium in the ranges between 3 to 10, had positive and negative effects on removal efficiency depending on pH value. Keywords: Electrical energy consumption, NO removal, UV/H2O2