SCR脱硝过程中硫酸氢铵形成特性实验研究

Experimental Research on ABS Formation Characteristics in SCR Denitrification Process

在自主设计的实验台上开展硫酸氢铵（ABS）形成特性实验,研究了温度和反应物体积分数对ABS形成机理的影响,通过热重分析实验得到ABS的挥发温度,并计算ABS分解反应的吉布斯自由能,从而得到ABS的热力学分解温度.结果表明：ABS的形成是温度和反应物体积分数的函数,其形成温度在220-261℃;φ（NH3）与φ（H2SO4）乘积越大,ABS的形成温度越高;H2SO4过量且体积分数一定的情况下,φ（NH3）越大,ABS沉积量越大;相反,若φ（NH3）一定,φ（H2SO4）对ABS沉积量的影响不大;热重分析实验显示,ABS的挥发温度为173.7℃,热力学分解温度为447.18℃.

To study the effects of temperature and reactant concentrations on the formation mechanism of ammonium bisulfate （ABS）, characteristic experiments were conducted on a self-developed test setup, during which the vaporating point of ABS was obtained through thermogravimetric analysis, and subsequently its decomposition temperture was acquired by calculating the Gibbs free energy for decomposition of ABS. Results show that the formation of ABS is a function of temperature and reactant concentrations, and its formation temperature lies in 220-261 ℃ ; the larger the concentration product of NH3 and H2SO4, the higher the formation temperature of ABS; for a constant excessive concentration of H2SO4, the higher the concentration of NH3, the larger the ABS precipitation amount; whereas for a constant concentration of NH3, the effect of H2SO4 concentration on ABS precipitation is not obvious. Thermogravimetric analysis indicates that the volatization and decomposition temperature of ABS are respectively 173. 7℃ and 447.18℃.