The contents of sulfur and potassium in the coal and the residue before and after the water washing are measured by the high resolution SEM with EDX analysis.

• 用扫描电子显微镜(SEM)下的能量弥散X-衍射(EDX)考察了原煤及残炭洗涤前后硫、钾等元素的含量变化趋势。