筛板脱硫塔气液流动及运行参数的影响分析

Analysis of Multiphase Flow and Different Parameters Impact on a Sieve-plate Desulphurization Tower

基于筛板式脱硫喷淋塔的结构特点,研究了烟气流速、浆液循环量、液滴粒径和喷嘴形式对雾滴携带特性、筛板的整流效果、系统压损的影响。结果表明,烟气流速增加到3.6 m/s,液滴被携带的作用明显增加,烟气流速增加,除雾器入口的雾滴浓度明显增加,系统压损增大;而循环量对1 300μm雾滴携带没有明显影响,循环量增加,系统和整流层的压损明显增大;液滴粒径越小,其携带作用越弱,1 300μm以上液滴几乎没有被携带出脱硫吸收塔,而800μm以下液滴携带作用明显增强。液滴分级粒径由50μm增加到1 900μm,其系统压损由2 349 Pa降到975 Pa,除雾器段压损由361 Pa降到67 Pa,液滴粒径对塔内系统压损影响较大。对安装有五层喷淋层的吸收塔,在四层以上安装双向双头喷嘴对除雾器入口的雾滴浓度有明显增加,而三层以下是否安装对雾滴携带无明显作用,同时其携带作用增强,筛板的整流效果减弱。

Based on the structural characteristics of the sieve plate desulfurization spray tower,the influence of the flow velocity of flue gas,slurry circulation,droplet size and nozzle form on the carrying characteristics of fog drops,the rectifying effect of the sieve plate and the pressure loss of the system were studied.The results show that,with the increase of flue gas velocity to 3.6 m/s,the effect of droplet carrying is significantly increased,and with the increase of flue gas velocity,the concentration of fog droplet at the inlet of the defogger is significantly increased,and the pressure loss of the system is increased.The circulation volume has no obvious influence on the droplet diameter to 1 300 microns,but the pressure loss of the system and the rectifier layer increases obviously with the increase of the circulation volume.The smaller the droplet size,the weaker the effect of carrying and the drops over 1 300 microns have hardly been carried out the desulphurization absorber,while the drops below 800 microns have significantly increased their carrying capacity.Meanwhile droplet grading particle size has increased from 50 microns to 1 900 microns,pressure loss of the system decreased from 2 349 Pa to 975 Pa,pressure loss of the atomizer section decreased from 361 Pa to 67 Pa and droplet particle size has great influence on pressure loss of the system inside the tower.For absorption tower with 5 spray layers installed,the installation of bi-directional double-head nozzle above 4 layers significantly increases the concentration of fog drops at the entrance of the defogger,while the installation of bi-directional double-head nozzle below 3 layers has no obvious effect on the carrying of fog drops,and its carrying effect is enhanced,thus the rectifying effect of sieve plate is weakened.