NiO对白云石烧结性能的影响

Effect of NiO Addition on the Sintering Properties of Dolomite Clinker

以天然白云石为原料,采用二步煅烧工艺,研究了NiO对白云石烧结性能的影响,并采用扫描电子显微镜和X射线衍射仪对试样进行分析。研究结果表明:NiO添加到白云石中,高温烧结后,NiO完全固溶到MgO晶格中,改变MgO晶格常数,导致MgO晶格畸变,促进白云石的烧结。烧结温度为1600℃,无NiO添加剂时,白云石熟料的体积密度为3.30 g/cm3,显气孔率为3.4%,MgO晶粒尺寸为3.26μm。当NiO添加量为0.75%时,白云石熟料的体积密度提高到3.33 g/cm3,显气孔率为2.7%,MgO晶粒尺寸达到3.54μm。

In this study, nature dolomite was carried out in the presence of NiO by two-step calcination process. The samples were characterized by scanning electron microscopy and X-ray diffraction （XRD）. The results showed that the doping of NiO to natural dolomite changed the lattice constants of CaO and MgO and made the MgO lattice distortion happen, which consequentially reduced the activation energy of the grain growth and promoted the sintering of the dolomite. Without additive the bulk density and the apparent porosity of dolomite clinker after the sintering at 1600 ℃ were 3.30 g/cm3 and 3.4%, the crystal size of MgO only was 3.26 μm. But when the addition of NiO accounted to 0.75%, the bulk density and the apparent porosity of dolomite clinker after the sintering at 1600 ℃ were 3. 33 g/cm3 and 2. 7%, respectively. At same time, the crystal size of MgO reached to 3.54 μm.