蒸发塔技术用于脱硫废水的处理

Evaporation tower technology in FGD wastewater treatment

脱硫废水水质复杂、含有重金属,处理难度很大,为此开发了一种新型的脱硫废水处理技术——蒸发塔技术,可以实现脱硫废水的零排放。在实验室搭建了小型蒸发塔实验台,对脱硫废水的蒸发特性、热量衡算进行了研究。研究表明:导流板角度一定的情况下,脱硫废水主蒸发区在塔体中心位置,随着脱硫废水处理量的增加,主蒸发区域向塔壁和塔体下部偏移;导流板角度减小,高温区下移;雾矩受给液量和雾化器转速的双重影响,给液量越大,雾矩越大,转速越大,雾矩越小;塔径一定的条件下,适当调节进风量和导流板角度可增加脱硫废水的处理量;模拟计算表明,蒸发系统抽取热烟气量较少,不会对电厂热系统产生明显影响。

Flue gas desulfurization（ FGD） wastewater is difficult to treat because of its complex water quality characteristics and heavy metal components. A new FGD wastewater treatment technology called an evaporation tower was developed to realize FGD wastewater treatment with zero discharge. A pilot-scale evaporation tower was built to study its evaporation characteristics and heat balance performance,and findings showed that FGD wastewater evaporated in the center of the tower; the evaporation zone moved toward the direction of the tower wall and bottom with increases in the quantity of spray. Furthermore,the high-temperature zone moved downward with decreases in the guide plate angle. Meanwhile,the fog moment was enlarged with increases in the quantity of spray and was reduced with changes in the rotational speed of the atomizer. The FGD wastewater treatment amount could be increased by adjusting the inlet gas flow rate and guide plate angle. Finally,calculations showed that the treatment system had little effect on the thermal system used by the power station because of the small amounts of hot flue gas that were extracted.