Assmang Limited, which is jointly controlled by African Rainbow Minerals Limited and Assore Limited, has completed the 10 million tonne per annum Khumani Iron Ore Mine on time and within budget. The Khumani Expansion Project currently underway will increase Khumani’s capacity from the current level of 10 mtpa to 16 mtpa. Khumani is a brown-fields open-cast iron ore mining project. The plant consists of a crushing, washing and screening plant, with jig beneficiation to process off-grade ore. Grading is done to split out lumpy, medium and fine products. DRA was the main contractor and managing contractor for the expansion project, which include the construction of thickeners, launders and process water management systems. Qfinsoft played an important role in the Computational Fluid Dynamic (CFD) modelling of these systems. Multi-Phase CFD modelling was used to approximate transient start-up scenarios, evaluate launder fluid heights and flow velocities, resolve free surface boundaries and calculate residence time as particles move through these systems.