湿法烟气脱硫机理与工程对策

烟气脱硫关注的是对流扩散.脱硫工艺根据双膜理论的基本概念所确定的相际传质速度关系,为传质设备设计的主要依据.烟气脱硫技术中大量采用化学吸收法.合理提高吸收塔内烟气流速,有利于提高系统传质速率,减少传质阻力;通过对塔局部优化设计,可增强系统传质性能.对石灰石-石膏法而言,液气比决定了石灰石的消耗量.烟气中的飞灰既在液相膜表面结壳,阻碍石灰石的溶解,又影响脱硫系统含尘量排放指标,降低石膏品质.石灰石粒径确定原则为在保证一定脱硫率的前提下,获取最优的经济指标.浆液的pH值是影响脱硫效率的重要因素.通过对系统操作、运行和设计中几个重要参数的分析,提出相应工程对策.

Wet Flue Gas Desulfurization Mechanism and Engineering Countermeasures

Flue gas desulfurization pays attention to convection and diffusion.The main reference for mass transfer equipment design in desulfurization process is the inter-phase mass transfer speed relation ascertained by double film theory basic concept.Chemical absorption method is largely adopted in flue gas desulfurization.How to reasonably improve the flue gas flow rate in the absorption column helps to enhance mass transfer speed and reduce resistance;the local optimized design can strengthen the performance of mass transfer.To limestone/gypsum desulfurization, the ratio of liquid to gas determines the eonsumption quality. Fly ash in flue gas not only crusts on the surface, stopping the dissolving of limestone, but also affects the dust discharge index, reducing the quality of gypsum. In grain diameter determination, first the desulfurization rate should be ensured, to obtain the optimized ecsnomic index. PH value of the liquid is the main factor affecting desulfurization efficiency. The comesponding enginering countemeasures are put forward through analysis on several important parameters in operation, running and design.