School of Architecture, Building and Civil Engineering, Loughborough University, Loughborough, LE113 TU, UK.
Int J Environ Res Public Health. 2018 Feb 17;15(2):357. doi: 10.3390/ijerph15020357.
Due to urbanisation, there are large amounts of waste concrete, particularly in rapidly industrialising countries. Currently, demolished concrete is mainly recycled as aggregate for reconstruction. This study has shown that larger sizes (2-5 mm) of recycled concrete aggregate (RCA) removed more than 90% of P from effluent when at pH 5. Analysis of the data, using equilibrium models, indicated a best fit with the Langmuir which predicated an adsorption capacity of 6.88 mg/g. Kinetic analysis indicated the equilibrium adsorption time was 12 h, with pseudo second-order as the best fit. The thermal dynamic tests showed that the adsorption was spontaneous and, together with the evidence from the sequential extraction and desorption experiments, indicated the initial mechanism was physical attraction to the surface followed by chemical reactions which prevented re-release. These results suggested that RCA could be used for both wastewater treatment and P recovery.
由于城市化的发展，产生了大量的废弃混凝土，特别是在快速工业化的国家。目前，拆除的混凝土主要作为骨料回收再利用，用于重建。本研究表明，当 pH 值为 5 时，较大粒径（2-5 毫米）的再生混凝土骨料（RCA）可以去除废水中超过 90%的磷。使用平衡模型对数据进行分析表明，Langmuir 模型拟合度最好，预测的吸附容量为 6.88mg/g。动力学分析表明，平衡吸附时间为 12 小时，准二级动力学模型拟合度最好。热动力学测试表明，吸附是自发的，结合顺序提取和解吸实验的证据，表明初始机制是对表面的物理吸引力，然后是化学反应，防止了再释放。这些结果表明，RCA 既可以用于废水处理，也可以用于磷回收。
