Natural and Built Environments Research Centre, School of Natural and Built Environment, University of South Australia, Adelaide, Australia.
Natural and Built Environments Research Centre, School of Natural and Built Environment, University of South Australia, Adelaide, Australia.
J Environ Manage. 2020 May 15;262:110352. doi: 10.1016/j.jenvman.2020.110352. Epub 2020 Mar 3.
The management of abundant drinking water treatment sludge (DWTS) in landfill remains an important issue. The reuse of DWTS as construction material could contribute to the development of greener concrete product and to mitigating the detrimental environment effect from excessive production of DWTS. This paper investigates the potential of using DWTS as sand replacement in Concrete Paving Blocks (CPB). Five CPB mixtures were designed and the replacement ratios of sand by DWTS were 0%, 5%, 10%, 15%, and 20%, by weight. Properties of CPB such as compressive strength, water absorption, abrasion resistance, sulfate attack and metal leachability were determined. The results indicated that above 10% of DWTS, the replacement was detrimental to such properties of the CPB. Microstructure analysis proved the addition of DWTS could result in ettringite formation and the interfacial transition zone (ITZ) between the cement matrix and DWTS was more porous than that of sand. In addition, the metal leachability test of CPB demonstrated that the addition of high-copper DWTS into CPB was safe.
处理过量饮用水处理污泥（DWTS）的管理仍然是一个重要问题。将 DWTS 再利用为建筑材料有助于开发更环保的混凝土产品，并减轻因 DWTS 过度生产而对环境造成的不利影响。本文研究了将 DWTS 用作混凝土铺路砖（CPB）中的砂替代物的潜力。设计了五种 CPB 混合物，DWTS 替代砂的重量比分别为 0%、5%、10%、15%和 20%。测定了 CPB 的抗压强度、吸水率、耐磨性、硫酸盐侵蚀和金属浸出等性能。结果表明，DWTS 的替代率超过 10%时，会对 CPB 的这些性能产生不利影响。微观结构分析证明，添加 DWTS 会导致钙矾石的形成，水泥基质与 DWTS 之间的界面过渡区（ITZ）比砂更多孔。此外，CPB 的金属浸出性测试表明，将高铜 DWTS 添加到 CPB 中是安全的。
