期刊
WASTE MANAGEMENT
卷 134, 期 -, 页码 21-31出版社
PERGAMON-ELSEVIER SCIENCE LTD
DOI: 10.1016/j.wasman.2021.07.036
关键词
MSWI fly ash; Pressure-assisted sintering; Sintering kinetics; Sintering mechanism
资金
- National Key Research and Development Program of China [2019YFC1903903]
The study utilized pressure-assisted sintering method to treat MSWI fly ash, producing high-strength ceramic products with compressive strength significantly higher than conventional construction materials, while heavy metals leaching concentrations were below the standard limit. Increased mechanical properties and decreased heavy metals leaching concentrations were mainly attributed to the increased density and crystalline degree.
Municipal solid waste incineration (MSWI) fly ash disposal is an urgent task with some technical bottlenecks. In this study, a novel pressure-assisted sintering method was employed to treat the MSWI fly ash. A series of pressure-assisted sintering experiments were carried out by varying mechanical pressures and sintering temperatures, and their properties of compressive strength, density and heavy metals leaching behavior were determined to screen out the optimal conditions. Instrumental analysis of XRF, SEM, XRD and TEM-EDX and calculation kinetics were conducted to explore the enhancement mechanism of pressure-assisted sintering. With the help of mechanical pressure, a high-strength ceramic product was produced from MSWI fly ash sintered at a low temperature (400 degrees C), which never occurred in the conventional low-temperature sintering process. Maximum compressive strength of 218.30 +/- 4.08 MPa was obtained at 400 degrees C and 100 MPa, which was much higher than conventional construction materials of brick and cement. In addition, the leaching concentrations of heavy metals obtained from pressure-assisted sintering process were lower than the standard limitation. The SEM and XRD results revealed that the increased mechanical properties and the decreased heavy metals leaching concentration were mainly attributed to the increased density and crystalline degree. The kinetics calculation results indicated that the sintering activation energy was much lower than the sintering process without pressure, suggesting surface diffusion and grain boundary diffusion were main sintering mechanisms in the pressureassisted sintering process. These findings proved that pressure-assisted sintering could be a promising method to treat fly ash together with producing high-value building materials.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据