School of Materials Science and Engineering, Nanchang University, Nanchang, Jiangxi, 330000, China.
School of Materials Science and Engineering, Nanchang University, Nanchang, Jiangxi, 330000, China.
J Environ Manage. 2020 Jul 1;265:110551. doi: 10.1016/j.jenvman.2020.110551. Epub 2020 Apr 8.
In recent years, lithium slag (LS) has increased sharply with the development of lithium industry, which has caused serious environmental problems. However, the utilization of this industrial waste residue has been a difficult topic in lithium industry. In this paper, the effects of LS on mineral crystal type, ionic solid solution, decomposition temperature of CaCO and strength of white Portland cement clinker were studied by XRD, FT-IR, DSC, SEM-EDS and other means. The results show that LS can stabilize the M1 crystal of CS, improve the crystallinity of CA, and reduce the content of ACn. The LS content of 5 wt% can reduce the decomposition temperature of CaCO about 10 °C, but increase the low eutectic temperature of materials. Na elements tended to be dissolved in the intermediate phase, while Al3+ dissolved in calcium silicate may replace Ca or Si. Sintering white Portland cement clinker with appropriate content of LS can effectively reduce the content of f-CaO and greatly improve the early compressive strength of clinker. Therefore, LS within 5 wt% can be used as high quality raw material of white cement, which can recycle LS.
近年来，随着锂工业的发展，锂渣（LS）急剧增加，这造成了严重的环境问题。然而，这种工业废渣的利用一直是锂工业的一个难题。本文采用 XRD、FT-IR、DSC、SEM-EDS 等手段研究了 LS 对矿物晶体类型、离子固溶体、CaCO 分解温度和白色波特兰水泥熟料强度的影响。结果表明，LS 可以稳定 CS 的 M1 晶体，提高 CA 的结晶度，降低 ACn 的含量。LS 含量为 5wt%时，CaCO 的分解温度约降低 10°C，但降低材料的低共熔点。Na 元素倾向于溶解在中间相中，而 Al3+溶解在硅酸钙中可能取代 Ca 或 Si。用适量 LS 烧结白色波特兰水泥熟料可以有效降低游离氧化钙的含量，极大地提高熟料的早期抗压强度。因此，LS 含量在 5wt%以内可作为优质白水泥原料，实现 LS 的回收利用。
