可再生乙二胺湿法烟气脱硫实验研究

Experimental Study on the Regenerable Wet Flue Gas Desulfurization With Ethylenediamine

以乙二胺为主剂，硼酸、磷酸、柠檬酸和硫酸为添加剂，配制乙二胺类烟气吸收剂，测定其对SO2吸收容量和脱除效率的影响。结果显示，乙二胺／硼酸对SO2吸收容量为450mg／L，脱硫率达97％；同时研究乙二胺／硼酸溶液10次吸收一解吸循环过程。数据表明，SO2的脱除效率达99％，解吸后pH稳定在6．10-23；选择乙二胺／硼酸为最佳脱硫剂，在鼓泡反应器中对湿法烟气脱硫（wetflue gas desulphurization，WFGD）工艺进行研究。通过改变吸收剂温度、乙二胺浓度、吸收剂pH和SO2进口浓度，探讨其对脱硫率的影响。确定吸收SO2适宜的工艺条件：吸收剂温度30℃，乙二胺浓度0．3mol／L，吸收剂pH为8．5。结果显示，实验范围内，烟气中SO2浓度越大，脱硫率越高。

Boric acid, phosphate acid, citric acid, and sulfuric acid as additives, a series of ethylenediamine-based desulfurizers were prepared. SO2 absorption capacity and removal efficiency were studied. The results show that absorption capacity of SO2 in ethylenediaminefooric acid solvent is 450 mg/L, and the desulfurization efficiency reaches to 97%. The cycles of ethylenediamine/boric acid solvent were also performed for ten times. The desulfurization efficiency reaches above 99% and pH value of the solvent are stable at 6.10-6.23. Ethylenediamine/boric acid solvent was selected as a better absorbent to study the wet flue gas desulphurization （WFGD） process on a bubbling system. By changing the temperature, the ethylenediamine concentration, pH value and SO2 inlet concentration, and the impacts on the SO2 removal efficiency were investigated. The experimental results show that the suitable conditions for SO2 absorption are following： absorption temperature is 30℃, concentration of ethylenedi- amine in the absorbents is 0.3 mol/L, and pH value of the solution is 8.5. It is also found that the desulfurization efficiency increases with the initial SO2 concentration increasing.