Environmental Processes Laboratory (LAPAM), Chemical Engineering Department, Federal University of Santa Maria - UFSM, Santa Maria, Brazil.
Environ Technol. 2021 Aug;42(20):3205-3217. doi: 10.1080/09593330.2020.1725141. Epub 2020 Feb 11.
This work aims to perform a comparative study of two mechanical processes for the recycling of metals from coaxial cables (aluminium and copper-clad steel): Process I - comminution, sieving and electrostatic separation; and Process II - comminution, magnetic separation and electrostatic separation. Characterization techniques were performed on the cables to discover their composition. The parameters evaluated of electrostatic separation were: roll speed (), electrostatic electrode distance (D2), voltage applied to the electrodes () and splitter angle (). The best conditions for electrostatic separation were: Process I - = 30 rpm, D2 = 8 cm, = 30 kV and = 0°; Process II - = 10 rpm, D2 = 10 cm, = 25 kV and = 2.5°. Process I presented aluminium with purity of 99.51% and recovery efficiency of 94.53%, as well as copper-clad steel with purity of 96.79% and recovery efficiency of 99.68%. Process II presented aluminium with purity of 96.51% and recovery of 70.12%, as well as copper-clad steel with purity of 99.53% and recovery of 99.46%. A simplified economic assessment was performed on both process, and Process I has demonstrated to be the most profitable for coaxial cable recycling. The results showed that Process I is promising for the recovery of metals from cables due to its simplicity and lower cost, being capable of wide application to other processes that contain a mixture of conductive and non-conductive particles.
本工作旨在对两种用于从同轴电缆(铝和铜包钢)中回收金属的机械工艺进行比较研究:工艺 I - 粉碎、筛分和静电分离;工艺 II - 粉碎、磁分离和静电分离。对电缆进行了特性分析技术,以发现其组成。评估静电分离的参数为:辊速()、静电电极距离(D2)、施加到电极的电压()和分流器角度()。静电分离的最佳条件为:工艺 I - = 30rpm,D2 = 8cm, = 30kV, = 0°;工艺 II - = 10rpm,D2 = 10cm, = 25kV, = 2.5°。工艺 I 得到纯度为 99.51%、回收率为 94.53%的铝和纯度为 96.79%、回收率为 99.68%的铜包钢;工艺 II 得到纯度为 96.51%、回收率为 70.12%的铝和纯度为 99.53%、回收率为 99.46%的铜包钢。对两种工艺进行了简化的经济评估,结果表明工艺 I 更适合同轴电缆回收。结果表明,工艺 I 具有较高的金属回收效率和经济效益,在处理含有导电和非导电颗粒混合物的其他过程中具有广泛的应用前景。