IN-SITU DETERMINATION OF CURRENT DENSITY DISTRIBUTION AND MASS TRANSFER MODELING OF A CONTINOUS ELECTROCOAGULATION REACTOR AND ITS EFFECT ON CHROMIUM AND NICKEL REMOVAL IN NICKEL MINE WASTEWATER: SIMULATION THROUGH COMPUTATIONAL FLUID DYNAMICS APPROACH

• Main Author: Risal Rusman, Muhammad
• Format: Theses
• Language: Indonesia
• Subjects: Teknik saniter dan perkotaan; teknik perlindungan lingkungan
• Online Access: https://digilib.itb.ac.id/gdl/view/86620
• Institution: Institut Teknologi Bandung

As a rapidly growing sector, Nickel mining faces environmental challenges due to resource exploitation. Open-pit mining in laterite deposits can result in impacts such as topographical changes and declining water quality due to the oxidation of minerals in the overburden layer, leading to contamination by hazardous metals like chromium and nickel that pose risks to human health and the environment. As a country rich in natural resources, Indonesia has a total nickel resource of 143 million tons and reserves of 49 million tons. This study explores electrocoagulation as an effective method for removing pollutants from nickel mine runoff water. The results indicate that using iron electrodes is more efficient in removing hexavalent chromium (Cr(VI)), achieving 99.76% removal at a current of 2 A and a flow rate of 0.99 liter/minute. For total nickel, the removal efficiency reaches 99.82% with a specific energy consumption of 0.48 kWh/gram. Meanwhile, aluminum electrodes achieved a Cr(VI) removal of 99.76% and total nickel removal of 68.82% at a current of 6 A and a flow rate of 0.61 L/min, with a specific energy consumption of 10.73 kWh/gram. A positive correlation was found between current density and metal removal efficiency, with correlation values of 0.38 for Cr(VI) and 0.43 for nickel. These results indicate that increasing current density contributes to enhanced metal removal efficiency, with the main mechanisms involved being adsorption onto hydroxides and indications of electrodeposition on aluminum electrodes. Computational fluid dynamics (CFD) approaches can be used to predict flow distribution and current density in the metal removal process from nickel mine runoff water using a continuous electrocoagulation reactor.