CFD Tailings Dam Brazil

Modelling of several Tailings Dam Break scenarios with CFD, 2D-hydrodynamic and dispersion models

The client is operating a phosphate fertilizer plant in Uberaba, Brazil and investigates the expansion of the existing storage facilities for the by-product phosphogypsum.

Potential impacts of several storage failure scenarios including breaks at the tailings compartments, breaching of the clarification lagoons’ dikes and the resulting contamination of the nearby Rio Grande were analysed by AFRY Brazil based on numerical simulation results prepared by AFRY Austria.

While the hydrodynamic behaviour of the lagoon water is comparable to clear water, the phosphogypsum tailings flow was qualified as a Non-Newtonian fluid of Bingham-type, resulting in a vis-cous compartment outflow until a freezing process terminates the fluid motion.

The expected river contamination by 4 chemical parameters finally was simulated in a water quality model for the 80 km long river reach including a hydropower reservoir.

The hydro-numerical dam break simulations of water and tailings mud show which areas could be affected, how much polluted fluid enters the river and how flooding would develop over time. The resulting degree of river contamination and the duration of exceeding legal limits were determined.

This information is crucial for the adequate development of emergency action plans.

Facts to Project

VALE Fertilizantes

Services:

Break simulation of tailings compartments A/B/E/F and C/D
Dam break simulation of lagoons, cascade scenarios
Water quality and contamination simulation of Rio Grande
CFD-analysis of liquefied tailings outflow 8 scenarios
2D-hydrodynamic breach modelling for lagoons and compartment top ponds (14 scenarios)
1D-hydraulic and water quality simulation of the contamination at the Rio Grande at low and medium discharge (8 scenarios)
Visualization of results with animated video clips and GIS layers