Abstract:

Based on reaction plane theory, a mass transfer model of gas-liquid reaction absorption enhanced by reactive particles was established for the absorption of CO₂ into aqueous ammonia suspension with gypsum particles. The absorption enhancement factor was derived theoretically as E=1/λ^*+qβλ^*/2 with the dimensionless reaction position λ^* as the characteristic parameter. The validation experiments of CO₂ absorption into the suspension was carried out in a thermostatic reactor and the enhancement factors were measured with different solids loadings at selected speeds. The results showed that the enhancement factor increased from 1.69 to 2.10 when the solids loadings varied from 5% to 30% (mass); and it changed sparingly from 1.75 to 1.80 as the stirred speed varied from 150 to 300 r·min^-1. It revealed that the enhancement factors were controlled by the solids loading and dissolution rate of gypsum particles. The experimental data agreed well with the model prediction, with a maximum deviation of 10%.

Key words: absorption, enhancement factor, mass transfer, gypsum particles, CO₂ mineralization

摘要：

基于化学活性颗粒强化气液吸收机理,建立了磷石膏悬浮液强化氨法烟气CO₂捕集模型。以液膜内量纲一传质距离λ^*为特征参数,增强因子E=1/λ^*+qβλ^*/2。用恒温反应器在不同搅拌转速及磷石膏颗粒固含量下实验测定CO₂吸收增强因子对模型进行检验,结果表明:随颗粒固含量由5%增加到30%(质量分数),增强因子由1.69增加到2.10;而随搅拌转速从150 r·min^-1增加到300 r·min^-1,增强因子仅由1.75略增到1.80,表明磷石膏颗粒固含量及溶解速率是影响增强因子的控制性因素。实验结果与模型预测值吻合良好, 偏差小于10%。

关键词: 吸收, 增强因子, 传质, 磷石膏颗粒, CO₂矿化