Fig. 7: System boundaries considered in the reconstruction of the nickel sulfate dataset.
From: Improving process granularity of life cycle inventories for battery grade nickel
Six nickel concentrate processing routes are expanded to encompass all steps from mining to refining to nickel sulfate hexahydrate, battery-grade. Process steps are depicted as per descriptions from the impact assessment reports or process simulations selected for life cycle inventory modelling36,42,51,67,69. Concentrate pathways are separated between treatment of sulfide ores, tailings and laterite ores. For sulfide ores, from left to right, supply chains for flash smelting, pressure oxidation leaching and heap bioleaching are depicted. Next, the process route for tank-bioleaching of sulfide tailings is included. For laterite ores, the supply chain for the rotary-kiln-electric-furnace pathway is represented, followed by the value chain for high pressure acid leaching.
