Details

Autor(en) / Beteiligte

• Zhao, Shujie
• Xia, Ming
• Yu, Lin
• Huang, Xiao
• Jiao, Binquan
• Li, Dongwei

Titel

Optimization for the preparation of composite geopolymer using response surface methodology and its application in lead-zinc tailings solidification

Ist Teil von

• Construction & building materials, 2021-01, Vol.266, p.120969, Article 120969

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2021

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• •The feasibility study of geopolymer with high strength based on uncalcined coal gangue and blast furnace slag was conducted.•Response surface method was adopted for the optimization of preparation of composite geopolymer.•The effective solidification of heavy metals in lead-zinc tailing were achieved.•Solidified bodies have potential for application of construction purpose. The improper disposal of solid wastes could bring great pressures and threats to ecosystem. These detrimental impacts could be reduced or eliminated through solidification/stabilisation technology based on geopolymer. In this paper, composite based geopolymer prepared from coal gangue and blast furnace slag was used for the solidification of heavy metals in lead–zinc tailing (LZT). The impact of various factors on compressive strength development in composite geopolymer was evaluated through response surface experiment. Additionally, the sample with maximum strength (91.13 MPa) was chosen to solidify LZT. The results showed that strength of solidified bodies with addition of 70% LZT fell to 21.68 MPa. Based on leaching tests, these samples could potentially be used for construct applications, since leaching concentrations were far below the standard limits. Heavy metals in LZT were effectively solidified via physical and chemical ways, which was evidenced by chemical speciation analysis, mercury intrusion porosimetry, X-ray diffraction and scanning electron microscope with energy dispersive spectrometry analyses.