College of Environmental Science and Engineering, North China Electric Power University, Baoding, Hebei, People's Republic of China.
Shengfa Environmental Technology Co., Ltd., Xiamen, People's Republic of China.
Environ Technol. 2020 Feb;41(6):751-763. doi: 10.1080/09593330.2018.1509892. Epub 2018 Sep 6.
A novel zero-liquid discharge (ZLD) technology for desulfurization wastewater treatment is put forward in this paper. A ZLD reconstruction project performed on 2 × 320 MW desulfurization system was taken as the research object, to study the evaporator structure and the key factors affecting spray evaporation through CFD numerical simulation. The result shows that when the evaporator diameter is 2.4 m, the central density difference and the temperature difference of evaporator outlets are 0 kg/L and 0°C, under this condition, the wall sticking can be avoided effectively, and the uniformity of evaporator's outlet flow field is improved. As for the same amount of wastewater, small atomized particle size, high flue gas flow rate and high flue gas temperature are conducive to complete evaporation, and the optimum atomized particle size is 100-150 μm, flue gas velocity is 3-4 m/s and flue gas temperature is 250-260°C. In order to reduce adverse impact on the main flue duct, the optimized design scheme that extracting flue gas before and after the air preheater is put forward in the purpose of energy saving.
本文提出了一种脱硫废水零排放（ZLD）新工艺。以 2×320MW 脱硫系统的 ZLD 改造项目为研究对象，采用 CFD 数值模拟方法研究了蒸发器结构和影响喷雾蒸发的关键因素。结果表明，当蒸发器直径为 2.4m 时，蒸发器出口的中心密度差和温差分别为 0kg/L 和 0°C，在此条件下，可有效避免壁面结垢，提高蒸发器出口流场的均匀性。对于相同的废水量，较小的雾化粒径、较高的烟气流量和较高的烟气温度有利于废水的完全蒸发，最佳的雾化粒径为 100-150μm，烟气速度为 3-4m/s，烟气温度为 250-260°C。为了减少对主烟道的不利影响，提出了在空气预热器前后抽取烟气的优化设计方案，以达到节能的目的。
