Abstract
Within Bechtel Mining & Metals (Bechtel), the Aluminium Center of Excellence tests and validates design alternatives and operational variants to optimize equipment and facility design. In a recent study for a cathode re-lining facility for Ma'aden Aluminium (Ma'aden), a discrete event model (DEM) was developed to demonstrate the achievable potshell throughput by matching planned resources and the expected operating schedule.
The initial number of stalls and stations in the cathode re-lining facility layout was based on static calculations. The DEM provided the tools required to optimize the design resulting in capital expense (CAPEX) savings. Also, the need for extra potshells, spent pot lining (SPL) scrap containers and mobile equipment container delivery units was addressed. The model covered the full cycle of re-lining a potshell: from stopping the cell, cathode cooling time in the potroom, delivery of the potshell to the re-lining facility, undergoing all the steps of cooling, defining, shell repair, re-lining and return to potroom. Various operational patterns were tested; including the timing of cell shutdown, cathode cooling location (potroom or lining facility), potshell movement by transfer gantry and cranes, shift durations, operating schedule and other variables.