采用可再生胺法脱除烟气中SO_2

Removal of SO_2 in flue gas by regenerable amine process

为加快可再生胺法脱硫工艺的工业化进程,开发了一套撬装式脱硫再生中试装置,通过SO_2连续吸收解吸实验验证装置性能。分别考察吸收剂质量分数、pH、液气比(L/G)、解吸温度、SO_2进口含量对吸收和解吸效率的影响,结果表明:随吸收剂质量分数、pH、液气比的增大吸收率升高,而解吸率下降;解吸温度升高,吸收率变化不大,解吸率增速较快;SO_2进口浓度增大,吸收率和解吸率迅速降低。确定适宜工艺条件为:吸收剂质量分数30%,pH=6~8,吸收温度30℃,解吸温度(90±5)℃,液气比L/G=5.0 L·m-3。通过微分法导出体积总传质系数KGa的计算公式,并与相关工艺参数进行关联拟合,回归出填料吸收塔K_Ga经验模型:K_Ga=0.081(L/G)^(0.232 0)(8.91 w^(0.107 3)pH^(0.24)8e-0.32yA-1)。

To speed up industrialization of the regenerable amine sweetening process,a skid-mounted desulfurization and regeneration pilot device was developed. To test device performance,continuous SO_2 absorption /desorption experiments were conducted. The effect of varying absorbent mass fraction,pH,liquid-gas ratio,desorption temperature,and SO_2 inlet content on the absorption / desorption efficiency was investigated. The absorption rate increased with an increase in absorbent mass fraction,pH,and liquid-gas ratio,while the desorption rate decreased under these conditions. However,with an increase in desorption temperature,little effect was observed for the absorption rate,while a rapid growth in the desorption rate was observed. Furthermore,both the absorption and desorption rates decreased significantly with an increase in SO_2 inlet content. The optimal conditions for this process were therefore as follows： 30% absorbent mass fraction,pH 6—8,an absorption temperature of 30 ℃,a desorption temperature of（ 90 ± 5） ℃,and a liquid-gas ratio 5. 0 L·m^（-3）. To calculate the total volume of the mass transfer coefficient,KGa,the following mathematical expression was derived by differential methods to incorporate the relevant process parameters： K_Ga = 0. 081（LG）0. 232 0（ 8. 91w^（0.1073）pH^（0.248）e^（-0. 32yA）-1）.