Selection of additives to improve the efficiency of NOx and SO2 treatment in electron beam process

Abstract

In this study, we used mixed additives (base additive + oxidant) to increase the efficiency of the NOx and SO2 removal process using an electron beam. To assess the removal characteristic and efficiency of their compounds, influencing factors, such as the presence or absence of mixed additives, the stoichiometric ratio of the oxidant among the mixed additives, and the absorbed dose, were investigated. As a result, the removal efficiency when using NaOH as a base additive for both NOx and SO2 was higher than that when using NH4OH; in the case of NO, when NaOH was used as a sole additive, the efficiency was the highest at 87.90%. For NO2, when NaOH was mixed with the oxidant NaCl, the removal efficiency was confirmed to increase by about 6%. Furthermore, in most cases of NOx, as the absorbed dose increased to (0−20) kGy, the removal efficiency increased; but when NaClO2 was used as the oxidant, the removal efficiency tended to decrease. However, when a mixed additive of NaOH + NaClO2 was used at a low dose (5 kGy), the removal efficiencies of NO and NO2 were confirmed to be 89.28% and 88.16%, respectively, indicating high removal efficiency.