燃煤飞灰对痕量重金属吸附脱除的研究

STUDY ON ABSORPTION REMOVAL OF TRACE HEAVY METALS BY USING FLY ASH FROM COAL COMBUSTION

煤燃烧过程中生成的飞灰实际上是一种吸附痕量重金属的固体吸附剂 ,而飞灰结构和组分、灰中含碳量以及烟气温度等因素对飞灰吸附脱除痕量重金属有不同的影响。研究表明 ,这种吸附脱除机理是一种复杂的物理吸附和化学反应及化学吸附的组合 ,飞灰本身的结构特性和化学组分对痕量元素的吸附影响很大 ,烟温也是关键的影响因素 ,而灰中含碳量对其影响很小。

The fly ash produced in the process of coal combustion is actually a solid adsorbent of trace heavy metals, but many factors, such as structure and components of the fly ash, carbon content in the fly ash, and flue gas temperature etc., have different influence upon absorption removal of the trace heavy metals. Study results show that the mechanism of absorption removal is a complicated combination of physical absorption, chemical reaction, and chemical absorption. The structure specificity and chemical components of the fly ash proper have the greatest influence upon absorption of trace elements, the flue gas temperature is also a key influencing factor, but the carbon content in fly ash only has very little influence.