Mechanism and Kinetic Study on Elemental Mercury Oxidation in Flue Gas by Ozone Injection

The mechanism and kinetics of the elemental Hg oxidation in flue gas by ozone injection are investigated in detail by using quantum chemistry, kinetic simulation and experimental research. The reaction processes, activation energies and kinetic parameters are calculated and analyzed by quantum chemistry. From the comparison of activation energies, the Hg-0 oxidation ability of oxidizing radicals is that: NO3>O-3>NO2. The calculated results are in good agreement with literature experimental results. The calculated kinetic parameters are employed for kinetic simulation. The results of kinetic simulation are in good agreement with the experimental results. Results show that, the Hg-0 oxidization increases linearly when the mole ratio of O-3/NO becomes larger or the reaction temperature becomes higher. The reaction Hg+NO3=NO2+HgO is the key elemental reaction and the concentration of NO3 is the most important factor for affecting Hg-0 oxidation.