不同预处理方法对准东高碱煤中碱金属含量测定的影响

Effect of pretreatment methods on the determination of alkali metal content in high alkali metal Zhundong coal

以四种不同的准东高碱煤及气化飞灰为研究对象,对高碱煤及气化飞灰中碱金属(Na、K)的赋存形态,以及不同预处理方法(低温灰化法、直接消解法、中国国标法、萃取法及氧弹燃烧法)对准东高碱煤及气化飞灰中碱金属(Na、K)含量测定的影响进行了测试分析。结果表明,准东高碱煤中碱金属Na主要以水溶态形式存在,碱金属K主要以水不溶态形式存在;不同的预处理方法对准东高碱煤中碱金属(Na、K)含量的测定结果影响显著,对于准东高碱煤及气化飞灰中碱金属(Na、K)含量测定,建议采用氧弹燃烧法,萃取法也可以相对准确地反映煤中碱金属Na的含量。

High alkali metal coal from four coal mines in Zhundong coalfield and its gasification fly ash were used to investigate the occurrence of alkali metal with five pretreatment methods including lowtemperature ashing,microwave digestion,national standards,cascade extraction and oxygen bomb combustion. The results showthat the sodium in the high alkali metal coal exists mainly in the water soluble form,and the potassium is in the water insoluble form; The method of oxygen bomb combustion is the optimum one to determine the content of Na and K in high alkali coal and gasification fly ash,and the method of cascade extraction is also a better one to determine the content of Na.