A new technique to simultaneously oxidize NO and SO2 in flue gas

Based on atmospheric chemistry research, a new method was presented to simultaneously oxidize NO and SO2 in flue gas. A mechanism analysis was given about the process. Influences of reaction temperature, additive dose and gas composition on both NO and SO2's oxidation were investigated experimentally, and the result showed that HNO3 can oxidize both NO and SO2 under proper conditions. NO and SO2's oxidation ratios first increased with temperature, then decreased with temperature after 750K. NO and SO2's oxidation ratios increased first fast with HNO3's concentration, then SO2's oxidation ratio increased slowly after 100ppm HNO3, and NO's oxidation ratio decreased slowly because of NO's generation by HNO3's decomposition. NO and SO2's oxidation ratios increased with O-2's concentration nearly proportionally. At fixed condition, NO's oxidation ratio decreased with NO's concentration and SO2's oxidation ratio first increased, then decreased with NO's concentration, which indicated a favorable chain reaction and an adverse competitive reaction coexist in the process.