Abstract:Key factors effecting desulfurization of low concentration SO2 flue gas with electrolytic purifying waste solution and the optimum technological conditions were explored. The results indicate that desulfurization efficiency was apparently affected by initial SO2 concentration of flue gas, pH value of absorption liquid, ratio of liquid to gas (L/G), and oxidation reaction time. Under small-scale field experiment conditions, the optimum desulfurization process conditions include inlet SO2 concentration of ≤4 000 mg/m3, pH value of absorption liquid of ≥6, L/G of 4.5 L/m3, and oxidation reaction time after desulfurization of 10 min. Based on the results, double medium desulfurization process was designed, in which electrolytic purifying waste solution was the main desulfurization medium and sodium hydroxide was the absorbing guarantee medium under abnormal condition, at the same time, desulfurization tower with binary system was designed and implemented. The absorption effect is remarkable and offgas meets standard all the time.