The unburnt carbon exists in fly ash as two kinds of form, honeycombed or spongy carbon monomer, and commensal together with silicon and aluminium inside sinking and floating beads.

• 粉煤灰中的炭有两种存在形态,一种是蜂窝状和海绵状的纯炭粒单体,另一种则与硅、铝结合存在于漂珠和沉珠内部。