基于反应工程法的脱硫废水液滴蒸发特性数值研究

Numerical Research on Evaporation Characteristics of DesulfurizationWastewater Droplets Based on Reaction Engineering Approach

采用数值模拟方法研究了干燥塔进口烟气温度、进口烟气流量、塔径对某燃煤电厂脱硫废水旋转喷雾蒸发设备中液滴蒸发特性的影响。为完善液滴蒸发传热传质模型,使用反应工程法(REA)中的液滴表观活化能函数描述液滴的传热传质过程,并将其编译到离散相计算过程中。结果表明:提高进口烟气温度与进口烟气流量,可缩短液滴的蒸发停留时间和竖直蒸发距离;增大干燥塔塔径可延长高温烟气在塔内的停留时间,增大旋流强度,进而加快液滴的换热蒸发过程。

Influence of inlet flue gas temperature,inlet flue gas flow rate and tower diameter on evapration characteristics of desulfurization wastewater droplets in a rotary spray evaporation equipment of a coal-fired power plant was studied by numerical simulation.In order to improve the heat and mass transfer model of droplets evaporation,their heat and mass transfer process was described by apparent activation energy function of droplets in reaction engineering approach(REA)and compiled into the calculation process of discrete phase.Results show that increasing the temperature and flow rate of inlet flue gas can shorten the evaporation residence time and vertical evaporation distance of droplets.Increasing the diameter of drying tower can prolong the residence time of high-temperature flue gas in the tower and improve the swirl intensity,which can accelerate the evaporative heat transfer process of droplets.