旋转喷雾塔Ca（OH）2／NaClO2联合脱硫脱硝数值模拟

摘要

针对开发低温烟气联合脱硫脱硝技术的需求，采用欧拉拉格朗日方法，建立了旋转喷雾塔气固流动与脱硫脱硝反应耦合的三维数理模型。气相场采用k-ε湍流模型，SO2，NOx的吸收采用双膜理论模型。以2个180 m2烧结烟气的旋转喷雾塔为模拟对象，采用Ca（OH）2/NaClO2浆液作为吸收剂，考察了NaClO2/Ca（OH）2摩尔比、烟气流速、烟气温度、SO2和NO的浓度等对烟气二氧化硫和氮氧化物脱除效率的影响。研究结果表明：随着溶液中NaClO2/Ca（OH）2摩尔比的增加，氮氧化物的脱除效率显著提高，二氧化硫的脱除效率无明显变化；随烟气流速、温度的增大，二氧化硫以及氮氧化物脱除效率均有所降低；氮氧化物的脱除效率随SO2浓度的增大无显著变化，而二氧化硫的脱除效率明显降低；随NO浓度的增加，氮氧化物脱除效率明显降低，二氧化硫脱除效率无显著变化。%A three-dimensional numerical model of a rotating spray tower gas-solid flow coupling with simultaneous desulfurization and denitration reaction was set up on the Euler-Lagrange approach for the demand of the development of low temperature flue gas desulfurization and denitration tech-nology.The k-εturbulence model was used for the gas phase,and the two-film theory absorption model for the absorption of SO2,NOx.The investigation of the influence of NaClO2/Ca(OH)2 mo-lar ratio,gas velocity,gas temperature,SO2 and NO concentration on the removal efficiency of sul-fur dioxide and nitrogen oxides using Ca(OH)2/NaClO2 slurry as the absorbent was carried out on a model of 2 ×1 80 m2 sintering gas rotating spray tower.Research results show that with the increase of NaClO2/Ca(OH)2 molar ratio,the removal efficiency of nitrogen oxides increases significantly, while the removal efficiency of sulfur dioxide has no obvious change.With the increase of gas veloc-ity and temperature,both the removal efficiency of sulfur dioxide and nitrogen oxides decrease.The removal efficiency of nitrogen oxides has no significant change with the increase of SO2 concentra-tion,while the removal efficiency of sulfur dioxide decreases obviously.With the increase of NO concentration,the removal efficiency of nitrogen oxides decreases obviously,while the removal effi-ciency of sulfur dioxide has no significant change.