喷淋塔内液滴运动及分布特性的研究

Research on Characteristics of Droplet Motion and Distribution in Spray Tower

以工业规模喷淋吸收塔为研究对象,建立了塔内液滴运动数学模型,考察了液滴直径、液滴初速度、空塔气速、喷淋密度对塔内液滴运动及分布特性的影响。研究结果表明:液滴的临界粒径随空塔气速的增加而增大,终端沉降速度仅与液滴直径有关;增大气速或减小液滴直径可显著增大液滴在塔内的停留时间;塔内持液率及比表面积正比于喷淋密度,反比于液滴直径,提高空塔气速,粒径较小的液滴在塔内分布更为稠密,能显著提高传质面积。

A droplet dynamic model was presented for studying the operation of spay tower with industrial scale. The effects of operating parameters, such as droplet size, initial droplet velocity, superficial gas velocity and spray density to the characteristics of droplet motion and distribution were investigated. The results showed that the critical droplet size is increased with the increase of superficial gas velocity, and the terminal drop velocity is only related to the droplet diameter; the droplet residence time is increased significantly by increasing the superficial gas velocity or reducing the droplet size; the liquid holdup and specific surface area are proportional to spray density respectively, and inversely proportional to droplet diameter. Therefore, actual mass transfer area can be significantly greater at higher flow rates as small droplets deposit themselves more densely at key interfaces in the tower.