<p>Lead–zinc tailings (LZT), a low-value mining waste, pose significant environmental and health risks due to their massive accumulation. This study addresses the need for harmless and efficient treatment of LZT by successfully producing lightweight aggregates (LWA) from 100% solid waste (low-cost LZT and poor-quality fly ash) without secondary pollution. The relationship between sintering conditions and LWA properties was investigated, revealing that sintering temperature significantly influences LWA performance more than other parameters. Specifically, it is the core factor controlling particle density, while both sintering temperature and time strongly affect compressive strength. Microstructure analysis showed that over 50% of the total pore area consisted of pores with diameters of 100–1000&#xa0;μm. Insufficient preheating or excessively high sintering temperatures led to the formation of pores larger than 1&#xa0;mm, while extending sintering time from 20 to 40&#xa0;min increased the proportion of 100–1000&#xa0;μm pores. XRD and FTIR analyses indicated that strength development was attributed to the formation of aluminosilicate skeletons and feldspar phases during sintering. Life cycle assessment (LCA) revealed that sintering at 1100–1150&#xa0;°C for 30–35&#xa0;min optimally balances LWA strength, energy consumption, environmental impact, and cost. This study offers an innovative and eco-friendly strategy for low-energy utilization of multi-source solid waste.</p>

错误:搜索内容不能为空,请输入英文关键词
错误:关键词超出字数限制,请精简
高级检索

Physical properties and microstructure of sustainable lightweight aggregates prepared from lead–zinc tailings and fly ash under different sintering regimes

  • Jianxiang Huang,
  • Shouwei Jian,
  • Hongbo Tan,
  • Xiangguo Li,
  • Jian Huang,
  • Yang Lv,
  • Baodong Li,
  • Xin Gao,
  • Bo Peng,
  • Xiwen Guan

摘要

Lead–zinc tailings (LZT), a low-value mining waste, pose significant environmental and health risks due to their massive accumulation. This study addresses the need for harmless and efficient treatment of LZT by successfully producing lightweight aggregates (LWA) from 100% solid waste (low-cost LZT and poor-quality fly ash) without secondary pollution. The relationship between sintering conditions and LWA properties was investigated, revealing that sintering temperature significantly influences LWA performance more than other parameters. Specifically, it is the core factor controlling particle density, while both sintering temperature and time strongly affect compressive strength. Microstructure analysis showed that over 50% of the total pore area consisted of pores with diameters of 100–1000 μm. Insufficient preheating or excessively high sintering temperatures led to the formation of pores larger than 1 mm, while extending sintering time from 20 to 40 min increased the proportion of 100–1000 μm pores. XRD and FTIR analyses indicated that strength development was attributed to the formation of aluminosilicate skeletons and feldspar phases during sintering. Life cycle assessment (LCA) revealed that sintering at 1100–1150 °C for 30–35 min optimally balances LWA strength, energy consumption, environmental impact, and cost. This study offers an innovative and eco-friendly strategy for low-energy utilization of multi-source solid waste.