School of Metallurgy and Environment, Institute of Environmental Science and Engineering, Central South University, Changsha 410083, China.
School of Metallurgical and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China.
Int J Environ Res Public Health. 2020 Apr 16;17(8):2762. doi: 10.3390/ijerph17082762.
Lead smelting slag (LSS) has been identified as general industrial solid waste, which is produced from the pyrometallurgical treatment of the Shuikoushan process for primary lead production in China. The LSS-based geopolymer was synthesized after high-energy ball milling. The effect of unconfined compressive strength (UCS) on the synthesis parameters of the geopolymer was optimized. Under the best parameters of the geopolymer (modulus of water glass was 1-1.5, dosage of water glass (W(SiO+NaO)) was 5% and water-to-binder ratio was 0.2), the UCS reached 76.09 MPa after curing for 28 days. The toxicity characteristic leaching procedure (TCLP) leaching concentration of Zn from LSS fell from 167.16 to 93.99 mg/L after alkali-activation, which was below the limit allowed. Meanwhile, C-S-H and the geopolymer of the hydration products were identified from the geopolymer. In addition, the behavior of iron was also discussed. Then, the hydration process characteristics of the LSS-based geopolymer were proposed. The obtained results showed that Ca and Fe occupied the site of the network as modifiers in the glass phase and then dissociated from the glass network after the water glass activation. At the same time, C-S-H, the geopolymer and Fe(OH) gel were produced, and then the Fe(OH) was easily oxidized to Fe(OH) under the air curing conditions. Consequently, the conclusion was drawn that LSS was an implementable raw material for geopolymer production.
炼铅炉渣（LSS）已被确定为一般工业固体废物，它是中国原生铅生产中采用火法冶金处理水口山工艺产生的。通过高能球磨合成了基于 LSS 的地质聚合物。优化了无侧限抗压强度（UCS）对地质聚合物合成参数的影响。在地质聚合物的最佳参数下（水玻璃模数为 1-1.5，水玻璃用量（SiO+NaO）为 5%，水胶比为 0.2），养护 28 天后 UCS 达到 76.09 MPa。LSS 经碱激活后，Zn 的毒性特征浸出程序（TCLP）浸出浓度从 167.16 降至 93.99mg/L，低于允许限值。同时，在地质聚合物中鉴定出 C-S-H 和水化产物的地质聚合物。此外，还讨论了铁的行为。然后，提出了基于 LSS 的地质聚合物的水化过程特性。研究结果表明，Ca 和 Fe 作为改性剂占据玻璃相网络的位置，然后在水玻璃活化后从玻璃网络中解离。同时，生成 C-S-H、地质聚合物和 Fe(OH)凝胶，然后在空气养护条件下，Fe(OH)很容易氧化为 Fe(OH)。因此，得出结论认为 LSS 是地质聚合物生产的一种可行的原料。
