FGD石膏煅烧过程中汞释放特性研究

Characteristic of mercury release during FGD gypsum calcination

研究了空气气氛在40℃/min的升温速率条件下,4种FGD石膏加热过程中汞的释放规律,探讨以FGD石膏为原料生产石膏产品的煅烧和加热工艺过程中汞的再排放特性.研究结果表明,汞析出的主要温度段是200℃~400℃段,随着温度的继续升高,汞析出量逐渐下降;进一步对汞的析出形态分布进行了探讨,表明FGD石膏加热过程中,零价汞（Hg0）的释放量通常高于二价汞（Hg2＋）.

The attention was focused on the mercury release of four FGD gypsums during heating process with the heating rate of 40 ℃/min under air atmosphere.The characteristic of mercury release during FGD gypsum heating and calcining was analysed.The results indicate that the mercury discharge in four FGD gypsum samples is mainly related to the temperature range of 200 ℃ to 400 ℃,and beyond that range the release rate will descend with the increase of temperature.In the ingredient distribution of mercury release,elemental mercury（Hg0）discharges more than divalent mercury（Hg2＋） during the heating of FGD gypsum.