Comparison of Measuring Methods for the Equilibrium Constant of SO_3 and NH_3 Reaction

Zhuo Chen ； Yuanfa Zhuang ； Wentao Du ； Dengguo Yin ； Yi Deng

《International Core Journal of Engineering》 9卷7期 (2023/07) Pp. 109-117

https://doi.org/10.6919/ICJE.202307_9(7).0015

摘要

During the selective catalytic reduction (SCR) process for sulfur-containing coal combustion flue gas, the reaction between SO3 in the flue gas and NH3 added in SCR device will generate ammonium bisulfate (ABS) and ammonium sulphate (AS). Due to the high viscosity and corrosiveness of ABS liquid, the reaction product is harmful to the flue gas purification system. In order to predict the amount of ABS and AS production in flue gas, it is necessary to obtain the reaction equilibrium constant through experimental measurement. In this paper, the non-contact measuring method and the high-temperature isothermal condensation measuring method for reaction equilibrium constant measurement are compared theoretically. The comparison results indicate that non-contact measurement is more suitable for measuring low product concentration, while high-temperature isothermal condensation method is suitable for measuring high product concentration.

關鍵字

SCR ； Ammonium Bisulfate ； ABS ； Ammonium Sulphate ； Equilibrium Constant

參考文獻

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