用旋转填充床以双碱法脱除烟气中的SO_2

在旋转填充床中,以NaOH溶液为吸收液,进行SO2气体吸收的实验。考察了吸收液和气体流量的比(简称液气比)、旋转填充床转速、吸收液浓度和入口气体中SO2质量浓度对SO2脱除率(θ)和气相传质系数(KGa)的影响。实验结果表明,θ和KGa随液气比和吸收液浓度的增大而增加;随旋转填充床转速的提高,先降低后增加;随入口气体中SO2质量浓度的增大而降低。采用旋转填充床用NaOH溶液吸收SO2的最佳工艺条件是:吸收液浓度100mmol/L,液气比3.00～4.00L/m3,旋转填充床转速1200～1600r/min,入口气体中SO2质量浓度小于5g/m3。在此条件下,出口气体中SO2质量浓度低于50mg/m3,θ稳定在99%以上。

Removal of Sulfur Dioxide from Flue Gas in Rotating Packed Bed by Dual-Alkali Method

SO2 in flue gas was absorbed by sodium hydroxide solution as liquid absorbent in a rotating packed bed.Effects of ratio of liquid absorbent flow rate to gas flow rate,rotating speed,concentration of NaOH solution and mass concentration of SO2 in feed gas on removal rate of SO2(θ)and coefficient of mass transfer(KGa)were studied.θ and KGa increased with increasing of ratio of liquid absorbent flow rate to gas flow rate,and concentration of NaOH solution.θ and KGa decreased firstly and then increased with increasing of rotating speed.θ and KGa decreased with increasing of mass concentration of SO2 in feed gas.Under optimal experimental conditions:concentration of NaOH solution 100 mmol/L,mass concentration of SO2 in feed gas less than 5 g/m3,ratio of liquid absorbent flow rate to gas flow rate 3.00-4.00 L/m3 and rotating speed 1 200-1 600 r/min,mass concentration of SO2 in exit gas was reduced to below 50 mg/m3 and θ could reach around 99%.