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The mass transfer and kinetics of NOx absorption into (NH4)2SO3 solution, the main compound of an ammonia-based wet flue gas desulfurization process, have been investigated in a double-stirred reactor. Under the experimental conditions, the gas−liquid reaction between NOx and the (NH4)2SO3 solution without O2 coexisting is controlled mainly by the gas film because the (NH4)2SO3 concentration is higher than 0.05 mol/L. In this case, the absorption rate of NOx is found to be zero-order with respect to the (NH4)2SO3 concentration. The inlet partial pressure and the oxidation degree (Φ = NO2/NOx) have an apparent effect on the absorption rate of NOx. In this research, a simplified mathematical calculated model is applied to the simulation of the absorption process. The experimental results demonstrate that the orders of the reaction with respect to the concentration of NOx (NO2* or NO*) in the gas phase and the reaction rate constants of NOx (NO2* or NO*) with (NH4)2SO3 are all a function of the oxidation deg...

Iron leaching from fly ash has been investigated under simulated ammonia-based wet flue gas desulfurization conditions to determine the effects of the reaction temperature, initial pH value, liquid/solid ratio, and vibration frequency. The experimental results indicated that the ferric ion concentration in solution increased with the increase of the temperature and vibration frequency and the decrease of the pH value and liquid/solid ratio. The kinetics of iron leaching can be expressed as diffusion combined with a surface chemical reaction model. The reaction path can be described by the equation: 1 − (1 − α)1/3 = kt. The apparent activation energy was estimated to be about 20.01 kJ/mol. Such a value of the activation energy indicates that the leaching of iron under experimental conditions is controlled by both chemical reaction and diffusion.

In this study, the influences of different geometric nozzle electrodes on corona discharge characteristics, ozone and NOx formation characteristics, and NO conversion characteristics were investigated. In addition, an experiment that involved the NO conversion characteristics, relative to multinozzle electrodes, was performed. The results show that the different nozzle radii may transform the discharge modes. The increasing nozzle quantity can enlarge the corona region and increase the discharge current, while it almost has no effect on the onset voltage and sparking voltage. The ozone formation during corona discharge is affected by different geometric nozzle electrodes. More ozone is generated with the increasing nozzle radius and nozzle quantity. However, NOx concentrations are not affected much and the NOx concentrations are basically