Shang Shuo, Fan Haihong, Li Yuxiang, Li Lin, Li Zhou
College of Materials Science and Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Materials (Basel). 2022 Jan 3;15(1):325. doi: 10.3390/ma15010325.
SiC was chosen as the foaming agent, and river bottom silt, waste oil sludge, paint bucket slag, and fly ash were used as raw materials, to prepare lightweight ceramsite without adding any chemical additives. The effects of SiC dosing and sintering temperature on various properties of the ceramsite were studied, and the pore-forming mechanism of the lightweight ceramsite was clarified by thermal analysis and X-ray diffraction analysis. The results showed that the single ceramsite compressive strength, water absorption, bulk density, and porosity of ceramsite sintered at 1180 °C with 1.0% SiC were 2.15 MPa, 2.02%, 490 kg/m, and 23.85%, respectively. The major mineralogical compositions were quartz, fayalite, and kyanite, with small amounts of albite-low from 1140 to 1190 °C. Furthermore, the concentration of all tested heavy metals from ceramsite was lower than the maximum allowable concentration of the leaching solution specified in the Chinese national standard (GB 5085.3-2007), which reveals that this solid waste ceramsite will not cause secondary environmental pollution. The prepared ceramsite, exhibiting lower bulk density, high water absorption and porosity, and effective solidification of deleterious elements, can be used to prepare green lightweight aggregate concrete. Importantly, preparation of solid waste ceramsite is an effective way to dispose of hazardous wastes.
选用碳化硅作为发泡剂，以河底淤泥、废油污泥、油漆桶渣和粉煤灰为原料，在不添加任何化学添加剂的情况下制备轻质陶粒。研究了碳化硅掺量和烧结温度对陶粒各项性能的影响，并通过热分析和X射线衍射分析阐明了轻质陶粒的成孔机理。结果表明，在1180℃下烧结、碳化硅掺量为1.0%时，单一陶粒的抗压强度、吸水率、堆积密度和孔隙率分别为2.15MPa、2.02%、490kg/m³和23.85%。主要矿物组成是石英、铁橄榄石和蓝晶石，在1140至1190℃时有少量钠长石。此外，陶粒中所有测试重金属的浓度均低于中国国家标准（GB 5085.3-2007）规定的浸出液最大允许浓度，这表明这种固体废物陶粒不会造成二次环境污染。所制备的陶粒堆积密度较低、吸水率和孔隙率较高，且能有效固化有害元素，可用于制备绿色轻质骨料混凝土。重要的是，制备固体废物陶粒是处置危险废物的有效途径。
