PROCESSING WASTE ELECTRIC AND ELECTRONIC EQUIPMENT (WEEE) FOR PRECIOUS METAL RECOVERY

• Main Author: Putri Larasati, Aqila
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/84898
• Institution: Institut Teknologi Bandung

The rapid advancement of technology nowadays has led to more frequent replacement of electronic devices, resulting in an abundance of electronic waste, particularly Printed Circuit Boards (PCB). PCBs contain various valuable metals such as gold and copper. However, research on WEEE metal recovery is still limited and has never been directly conducted in laboratories in Indonesia. Therefore, this study contributes to realizing a circular economy and supporting the Sustainable Development Goals (SDGs), particularly goals number 9 (Industry, Innovation, and Infrastructure), number 12 (Responsible Consumption and Production), and number 13 (Climate Action). Copper and gold metals can be recovered from WEEE through the pyrometallurgical process of smelting. This study aims to determine the thermodynamic and techno-economic analysis of the recovery process of valuable copper and gold metals from WEEE waste. The thermodynamic analysis of this research was conducted using FactSage software version 7.3, while the mass and energy balance for techno-economic calculations were determined using HSC Chemistry software. The feed used in this smelting process includes PCBs, copper scrap, FCS slag, coke, and air. Four variations were conducted in this study, namely variations in slag feed composition, temperature, operating atmosphere, and oxygen amount in the oxidation stage. The research objectives are to determine the optimum conditions (temperature, operating atmosphere) in the reduction and oxidation stage that can yield high valuable metal (copper and gold) recovery, low impurity concentrations in the molten metal, and no solid formation in the system. The most optimal slag feed composition variation used was the FeO-SiO2-CaO system with a CaO composition of 91%. Based on the simulation results, the optimum conditions for the reduction stage were at a temperature of 1400°C and oxygen partial pressure (pO2) of 10-8 atm, while for the oxidation stage, the temperature was at 1100°C with an oxygen amount of 5200 kg. Under these conditions, the copper metal recovery reached 75% with a purity of 98.84%, while the gold recovery reached 99% but further purification steps were necessary. The techno-economic analysis of recovering valuable metals from WEEE yielded significant potential as a sustainable and economically viable source of valuable metals.