水泥掺量对水泥-垃圾焚烧飞灰固化体性能的影响

Effects of cement content on performance of MSWI fly ash-cement solidification body

引入单位飞灰重金属溶出的浓度与水泥的固化效率参数分析了水泥掺量对垃圾焚烧飞灰固化效果的影响,并提出了一种垃圾焚烧飞灰低成本、安全高效资源化利用的方法。结果表明:10%水泥的掺入可显著降低Pb、Cd的溶出,但是随着水泥掺量增加,固化体强度增大,水泥的固化作用发挥越不充分,固化效率显著降低。且当水泥掺量在40%以上时,水泥掺量的增加反而促进了单位飞灰Pb的溶出,对Pb的固化起反作用。此外,小掺量飞灰的掺入对水泥凝结时间、标准稠度用水量与力学性能均无不利影响,在控制Cl-的含量满足相关标准的前提下,将飞灰作为混合材应用于水泥生产,水泥的工作性能、力学性能及重金属离子的溶出性能均满足相应的要求,可实现飞灰的安全高效资源化利用。

Two conceptions,heavy metal leaching concentrations of unit MSWI fly ash and solidification efficiency of cement,was introduced for analyzing the effect of the dosage of the addition of cement on the solidification of MSWI fly ash with cement,and a method to efficient recycle MSWI fly ash was also recommend.The results showed that the concentration of Pb and Cd would be reduced significantly when the cement-mixing ratio approach to 10%.But with the increasing of cement content,the strength of solidification body increased obviously,and the solidification efficiency of cement reduced enormously.When the cement content was over 40%,the Pb leaching concentration of unit MSWI fly ash would be promoted with increasing of cement content,and the solidification of Pb harmed.Besides,low-volume fly ash to replace cement had no adverse influence on the setting time,water requirement of normal consistency and mechanical property of cement.On the precondition of Cl-content meeting the national standards,regarded MSWI fly ash as blending materials for producing cement,the workability,mechanical properties of cement and extraction toxicity of heavy metals were all fill with the technique requirement.The effective recycle of MSWI fly ash could be achieved.