化工学报2016，Vol.67Issue(10)：4446-4454,9.DOI:10.11949/j.issn.0438-1157.20160150
亲水改性碳钢极板用于PM2.5脱除
PM2.5 collection using surface-modified hydrophilic carbon steel collector
摘要
Abstract
Fine particles with aerodynamic diameters of<2.5μm (PM2.5) are significant pollution sources. Dust emission is restricted to less than 10 mg·m−3 under 6% oxygen in eastern China and wet electrostatic precipitators (ESPs) are encouraged for efficient removal of various fine particles in aerosol, especially in coal-fired power plant where strict air pollutant emission standards drive wide use of wet ESP as terminal control equipment. Previous studies showed wetting properties of a hydrophilically modified rigid collector and this study focused on fine particle collection performance of the modified collector at pilot scale. The characteristics of PM2.5 collection, mechanism of uniform water film and effect of main operation parameters on enhancement of particle collection efficiency were investigated. The results showed that the surface fiber layer of the modified rigid collectors reduced flue gas recoiling and particle electro-transportation resistance. A uniform and stable water film was maintained on surfaces of the modified rigid collectors at low washing water flowrate, which inhibited back corona occurrence and a secondary entrainment of dust as well as increased discharge current and flue gas humidity by evaporation of water film. The increase of particle charge number and electro-transportation speed enhanced the particle collection efficiency. With the increase of flue gas temperature, both discharge current and thermophoresis force gradually increased which could improve the particle collection efficiency. However, the increase of gas viscosity reduced the particles collection efficiency. The extension of residence time and the increase of applied voltage improved particle collection, whereas the inlet concentration of particles and the flushing water flowrate had little influence on particle collection. The wet ESPs of modified rigid collectors exhibited reduction of circulating water consumption per square meter by 86 percent and significant increase of particle collection efficiency for ultrafine particles with size of 0.04—0.48μm as well as overall collection efficiency of all particles at low electric voltage. Hence, the modified rigid collectors had good potentials for application.关键词
湿式静电除尘/改性刚性极板/PM2.5/脱除效率/水膜Key words
wet ESPs/modified rigid collector/PM2.5/particle collection efficiency/water film分类
资源环境引用本文复制引用
徐纯燕,常景彩,王翔,张静,崔琳,张波,马春元..亲水改性碳钢极板用于PM2.5脱除[J].化工学报,2016,67(10):4446-4454,9.基金项目
国家自然科学基金项目（51206097，51006063）；山东省自然科学基金（青年基金）项目（ZR2011EEQ019，2014EEM040，2014ZZCX05201）；山东大学基本科研业务费专项资金项目（2014QY001-04）。@@@@Foundation item：supported by the National Natural Science Foundation of China (51206097,51006063), the Natural Science Foundation of Shandong Province (ZR2011EEQ019,2014EEM040,2014ZZCX05201) and the Fundamental Research Funds of Shandong University (2014QY001-04) （51206097,51006063）
