NaOH-CO_(2)体系下并流立体旋流筛板塔传质性能

Experiments on mass transfer performance for tridimensional rotational flow sieve tray in a cocurrent column with NaOH-CO_(2) system

二氧化碳捕集是应对全球气候变暖问题的重要技术之一。本文使用NaOH溶液和CO_(2)作为实验体系,在并流塔中对立体旋流筛板(TRST)的传质性能进行实验研究,测定并计算出全塔及塔板段的气相总体积传质系数[K_(G)a_(e),(K_(G)a_(e))t],重点考察塔板安装数量和方式、空塔气相动能因子和喷淋密度、CO_(2)和NaOH浓度等参数的影响规律。研究结果表明,塔板段是传质过程的主要区间,增加塔板数量以及采用塔板逆向安装方式是提升传质性能的有效技术手段;塔板段的气相总体积传质系数随空塔气相动能因子和NaOH浓度的增加呈先增大后减小的趋势,随喷淋密度和CO_(2)浓度的增加而减小,最高可达12.18kmol/(m^(3)·h·kPa);建立塔板段的气相总体积传质系数的经验模型,模型计算值与实验数据的吻合性较好,相对误差小于20%。

Carbon dioxide capture is one of the important technologies to deal with global warming.In this paper,a cocurrent gas-liquid column was used as the experimental system to investigate the mass transfer performance of tridimensional rotational flow sieve tray(TRST)with NaOH solution and CO_(2).The volumetric overall mass transfer coefficient(K_(G)a_(e))was calculated from the experiment results under different operating conditions.The effects of operating parameters on K_(G)a_(e) and the K_(G)a_(e) of the tray section[(K_(G)a_(e))t]were investigated,including gas F-factor,spraying density,CO_(2)concentration,NaOH concentration,the tray number and installation method.The results showed that the tray section is the main place for mass transfer and the increase in tray number and backward installation can improve the mass transfer performance.The(KGae)t decreases with the increase in CO_(2)concentration and spraying density.The(K_(G)a_(e))t first increases and then decreases with the increase in NaOH concentration and gas F-factor.Under the experimental conditions,maximum of(K_(G)a_(e))t was 12.18kmol/(m3·h·kPa).Based on the experiments,the empirical correlation of the operating parameters of CO_(2) absorption on(K_(G)a_(e))t was established.The calculated values of(K_(G)a_(e))t are in good agreement with the experimental data,and the relative error is within±20%.