多级电场的粉煤灰物理化学性质差异及意义

THE DIFFERENCES IN CHEMICAL AND PHYSICAL PROPERTIES OF POWDER FLY ASH FROM MULTI ELECTROSTATIC PRECIPITATORS AND THEIR SIGNIFICANCE

以华能南京电厂为例，研究了燃煤电厂不同电场收捕的粉煤灰化学成分和物理性质的差异。从第一电场至第５电场，粉煤灰的平均粒径变小，化学成分也有一定的差别，而矿物相组成则基本相同；各种微量元素趋向于在四、五电场的细粒径灰中富集。采用多个装置分别收集干灰，可促使粉煤灰资源的优化。

There exist differences in the chemical compositions and some physical properties of powder fly ash(PFA) from multi electrostatic precipitators in the firing coal powder plant, which merit a study with the example of Huaneng Nanjing Power Plant in this paper. From the first electrostatic precipitator to the fifth, the average particle size of PFA decreases one after another, and there are also some differences in major chemical compositions, but their mineral phases are rather similar. Various trace elements tend to enrich in smaller particles of PFA from the fourth and fifth electrostatic precipitator. Collecting dry PFA from the electrostatic precipitators by multi equipment respectively can result in the PFA source optimization. As much as possible, the smaller particles of PFA escaping in atmosphere should be reduced in quantity.