粉煤灰烧制陶粒过程中二氧化硫的释放规律与形成机理

Emission and formation mechanism of sulfur dioxide in sintering process of coal ash ceramisite

研究了粉煤灰烧制陶粒过程中烟气二氧化硫的释放规律,同时对烧结前后粉煤灰与陶粒中不同形态硫含量和硫平衡进行了分析,探讨了烟气中二氧化硫的来源和转化机理。结果表明,烟气中约55%的二氧化硫来源于硫酸盐的还原,其余主要来自有机硫燃烧和亚硫酸盐的分解。烧制每千克陶粒所产生的二氧化硫量约为7.8 g。高温烧结过程中粉煤灰球内形成的还原性气氛导致了粉煤灰中硫酸盐向二氧化硫的还原转化。

The emission of sulfur dioxide in the sintering process of coal ash ceramisite was lnvestlgatea m detail, the sulfur content of different forms in coal ash and ceramisite was determinated, and the origin and for- mation mechanism of flue gas sulfur dioxide were also discussed. The experimental results show that 55% of sulfur dioxide originates from sulfate sulfur, and the rest of sulfur dioxide is mainly from the combustion of organic sulfur and decomposition of sulfite. It is also demonstrated that the discharge amount of sulfur dioxide for produc- tion of 1 kg ceramisite is about 7.8 g. The transformation from calcium sulfate to sulfur dioxide at high tempera- ture results from reductive atmosphere formed in the coal ash ceramisite.