Experimental research on the volatilization and condensation of ammonium bisulfate as SCR byproduct

In this paper, the research progress of ammonium bisulfate (ABS) volatilization in coal-fired power plants the SCR denitrification process was reviewed. Combination with self-made experiments, SEM, flue gas analyzer and TG-DTG curves of ABS and ion chromatography. The volatilization and condensation characteristics of ABS were investigated carefully. Results show that as the temperature increased by 50 °C, the ABS/AS volatilization rate increased by an order of magnitude. The decomposition process of ABS should have a two-step reaction. The reaction in the initial volatilization stage is ABS dehydration turned into (NH4)2S2O7. The reaction in the rapid volatilization stage is (NH4)2S2O7 decomposed into NH3, N2, SO2 and H2O. There is an inter-section in the reac-tion temperature range (especially 300 °C) between the two-step reaction. This research provides an experimental basis for temperature control of ABS to avoid air pre-heater fouling.