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 ^oC, 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 volatiliza-tion stage is ABS dehydration turned into (NH₄)₂S₂O₇. The reaction in the rapid volat-ilization stage is (NH₄)₂S₂O₇ decomposed into NH3, N₂, SO₂ and H2O. There is an inter-section in the reaction temperature range (especially 300 ^oC) between the two-step re-action. This research provides an experimental basis for temperature control of ABS to avoid air pre-heater fouling.