线管式热电子发射高温静电除尘器的数值研究

热电子发射式高温静电除尘技术是一种新颖的高温烟气净化方法,与传统的电晕式静电除尘技术不同,其以稀土钨制成的阴极在高温下发射电子的方式使烟气中的粉尘荷电,然后依靠电场力的作用将其捕集. 本文建立了线管式热电子发射式高温静电除尘器除尘过程数学物理模型,模型涵盖了颗粒荷电方程和颗粒浓度场. 利用MATLAB编写粉尘荷电量和除尘效率的计算程序,并进行数值计算,得到不同条件下粉尘荷电量和除尘效率,系统地研究了各种影响因素与除尘效率的关系,发现降低烟气进口流速、提高温度及收尘电压、减小除尘管半径,都可以提高除尘效率.

Numerical Investigation of Line Tube Thermal Emission StyleHigh-Temperature Electrostatic Precipitator

The thermal emission style high-temperature electrostatic precipitation is an innovative technique for cleaning up high-pressure hot flue gases. It utilizes the negative electrode made of tungsten doped with rare earth oxides which emits a large number of electrons when heated,instead of the corona discharge in traditional ESP,to charge dust particles. The charged particulate is collected by grounded plates under the action of the electric field. This article has established a dust collection mathematical and physical model of the wire-pipe thermal emission style high-temperature electrostatic precipitation,which has covered the particle charging equation,the electric field equation,the flow field and the dust pellet density field,compiled computational procedure of the dust particle charged quantity and the dust removal efficiency using MATLAB,and carried on the numerical calculus,obtained dust electrically charged quantity and dust removal efficiency under the dissimilar condition. This article has systematically studied each kind of influencing factor and the dust removal efficiency relationship,and quantitative pointed out:to reduce the flue gas flow rate of imports,to enhance the temperature and the particle charged area voltage and the dust removal area voltage,to increase the dust removal area length,to reduce dust removal tube’s radius,may obviously raise its particle collection efficiency.