赤泥基地聚物固化飞灰的试验研究

Experimental Study on Polymer Solidification Fly Ash in Red Mud Base

摘要: 在分析生活垃圾焚烧飞灰和赤泥物理化学性能的基础上，利用赤泥、碱激活剂和垃圾焚烧飞灰制备地聚合物。通过正交实验法得到最佳组分配方：40% wt飞灰，10% wt NaOH，50% wt赤泥，在水灰比为0.5、活化温度为800℃和60%湿度20℃恒温的条件下，养护14天后的抗压强度可达1.6 MPa。赤泥固化飞灰后的地聚物渗滤液中的中重金属达到《生活垃圾填埋场污染控制标准》(GB16889-2008)。制备的地聚物X射线衍射(XRD)分析得出含石英，钙铝黄长石，钙凡石，赤铁矿和石灰石等。扫描电镜(SEM)表征分析为不完整的细小致密的孔洞状网络结构，进一步验证地聚合物利用其类沸石结构可以把重金属包围在空腔内或被吸附而包容在聚合体中，进而固化飞灰中的重金属。

Abstract: Based on the analysis of the physical and chemical properties of domestic waste incineration fly ash and red mud, the paper uses red mud, alkali activator and garbage incineration fly ash to prepare ground polymers. The optimal group formula was obtained by orthogonal experimental method: 40% wt fly ash, 10% wt NaOH, 50% wt red mud, under the conditions of water ash ratio of 0.5, activation temperature of 800°C and 60% humidity of 20°C constant temperature, the compressive strength after 14 days of maintenance can reach 1.6 MPa. The medium and heavy metals in the ground polymer leachate after the solidification of the red mud meet the sanitary landfill standard of waste incineration fly ash (GB16889-2008). The prepared polymer X-ray diffraction (XRD) analysis yielded quartz—containing quartz, calcium-aluminum-yellow feldspar, calcium-vanite, hematite and limestone. Scanning electron microscopy (SEM) characterization and analysis of intact fine, dense, orophobic network structures further validates that the polymer can use its zeolite-like structure to enclose heavy metals in cavities or be adsorbed and encapsulated in polymers, thereby curing heavy metals in fly ash.