Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
Key Laboratory of Resources Chemistry of Nonferrous Metals, Ministry of Education, College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China.
J Hazard Mater. 2014 Apr 30;271:220-7. doi: 10.1016/j.jhazmat.2014.01.035. Epub 2014 Feb 19.
Novel lightweight bricks have been produced by sintering mixes of zinc smelting slag and clay. A two-stage sintered process has been proposed to recovery of Zn and Pb and reutilization of the zinc smelting slag. In the first stage of the process, called reduction and volatilization procedure, zinc and lead were reduced by the carbon contained in the zinc smelting slag and volatilized into the dust, and the dust can be used as a secondary zinc resource. In the second stage of the process, called oxidation sintering procedure, a lightweight brick was produced. Samples containing up to 60 wt.% zinc smelting slag and 40 wt.% kaolin clay were reduced at 1050°C for 6h, and then sintered at 1050°C for 4h. The recoveries of Zn and Pb from the brick are 94.5 ± 0.6% and 97.6 ± 0.2%, respectively. Low bulk density (1.42 g cm(-3)) and relatively high compressive strength (2 2MPa) sintered bricks were produced, and the leaching toxicity of the sintered bricks was below the regulatory thresholds of Chinese National Standards.
新型轻质砖是通过烧结锌冶炼渣和粘土的混合物制成的。提出了一种两阶段烧结工艺，以回收锌和铅并重新利用锌冶炼渣。在该过程的第一阶段，称为还原和挥发过程中，锌和铅被锌冶炼渣中的碳还原并挥发成粉尘，该粉尘可用作二次锌资源。在该过程的第二阶段，称为氧化烧结过程中，生产出了轻质砖。在 1050°C 下还原 6 小时，含有高达 60wt%的锌冶炼渣和 40wt%的高岭土的样品，然后在 1050°C 下烧结 4 小时。从砖中回收的 Zn 和 Pb 的回收率分别为 94.5±0.6%和 97.6±0.2%。生产出了低体积密度（1.42g cm(-3))和相对较高抗压强度（22MPa)的烧结砖，并且烧结砖的浸出毒性低于中国国家标准的监管阈值。
