稀磷酸喷淋吸收处理三乙胺废气的应用研究

Study on the application of dilute phosphoric acid for spray absorption of triethylamine exhaust gas

含三乙胺废气处理装置原采用水喷淋吸收技术,存在用水量较大、吸收效果不佳的问题,处理后的尾气不能达标排放。为提高三乙胺的吸收效果,采用稀磷酸代替水喷淋吸收处理废气。通过滴定试验研究了稀磷酸溶液与三乙胺的中和反应行为,并对反应过程中溶液的p H值和废气中挥发性三乙胺进行检测。结果表明:在磷酸质量分数为1.7%~5.1%时,三乙胺的饱和吸收容量随着磷酸浓度的增加而线性提高,三乙胺的饱和吸收摩尔容量是磷酸的2倍。磷酸浓度进一步升高,导致磷酸二级电离不充分,三乙胺的饱和吸收容量与磷酸摩尔比例下降。根据滴定试验结果,提出稀磷酸喷淋吸收三乙胺废气的处理方案,应用结果表明处理后废气达标排放,效果良好。

The water spray absorption technology is originally applied to treat triethylamine exhaust gas,but treatment effect is not satisfactory because of large amount of water consumption and treated exhaust gas substandard.In order to increase the absorption effect of triethylamine,dilute phosphoric acid is used to displace water to absorb triethylamine.The neutralization reaction behavior of dilute phosphoric acid solution with triethylamine is studied by titration experiments.The pH value and volatile triethylamine in the process are detected.The results show that saturated absorbtion capacity of triethylamine increases linearly with the increase of phosphoric acid in the concentration of1.7%to5.1%,while the saturated triethylamine absorption molar capacity is about twice that of phosphoric acid.With further increase of phosphoric acid concentration,the saturated triethylamine absorption molar capacity is less than twice that of phosphoric acid because it cannot be fully secondary ionized.Based on the experimental results,the spray absorption scheme of triethylamine exhaust gas is put forward.The application of dilute phosphoric acid for the treatment of triethylamine exhaust gas achieves good results.