钙钛锆石和榍石人造岩石固化模拟放射性焚烧灰的研究

SOLIDIFICATION OF SIMULATED RADIOACTIVE INCINERATION ASH WITH ZIRCONOLITE AND SPHENE SYNROC

以天然锆英石(ZrSiO4)、CaCO3、TiO2为原料,利用高温固相反应,借助X射线衍射(XRD)、扫描电子显微镜(SEM)等分析方法,进行了钙钛锆石(CaZrTi2O7)和榍石(CaTiSiO5)人造岩石固化模拟放射性焚烧灰的研究。结果表明:针对成分为CaO 60.9%(wt),TiO210.2%(wt),SiO26.16%(wt),Fe2O311.4%(wt)的焚烧灰,当模拟放射性焚烧灰掺量分别为20%、40%、60%时,最佳合成及烧结温度分别为1260℃、1230℃、1200℃。采用本实验的工艺技术和路线,可以制备得到性能优良的钙钛锆石和榍石人造岩石固化体,其最佳烧结及合成温度随模拟放射性焚烧灰掺量的增加而降低;可以将固化基材的合成与人造岩石体固化体的烧结工艺合二为一,易于实现工程化。

Making use of cheap natural zirconite, CaCO3 and TiO2 as raw materials, adopting high teraperature solid-state reaction, the study of solidification of simulated radioactive incineration ash was carried out with the zircondite and sphene by means of volume-densities measurement, X ray diffraction （XRD） and scanning electron microscopy （SEM）. The results indicate zirconolite and sphene synroc form with excellent capability can be prepared, and optimum sinter and synthesis temperature decrease as the the content of simulated radioactive incineration ash increases. When the content of simulated radioactive incineration are 20% ,40% ,60% （wt）,the suitable sinter temperature are 1230- 1290 ℃, 1200- 1260 ℃, 1170- 1260 ℃, respectively, and the optimum sinter and synthesis temperature are 1260℃, 1230 ℃, 1200 ℃, respectively. The zirconolite and sphene can be synthesized and the simulated radioactive incineration synroc form can be sintered at the same time, which makes the process workable in engineering.