Author(s): Felipe De La Fuente Saavedra, Jose M. Adriasola V.
Linked Author(s): José M. Adriasola V.
Keywords: Slurry; Spills; Copper Plant; Energy Failure; Hydraulic Works;
Abstract: Usually copper processing plants can be analyzed as a hydraulic system driven by gravity, although there are many pumped recirculation lines within the plants due to process requirements. The hydraulic system goes from the grinding area - where the coarse ore is mixed with water in mills to reduce the average solid particle size - down to the delivering areas of the final product (copper concentrate slurry) and waste (thickened tailings slurry). During normal operation, many pipes and tanks are full of slurry containing solid particles which can easily settle down if there is insufficient turbulence. Solids in slurries typically remain suspended due the turbulence produced by the impingement of slurry jets feeding a tank or the presence of mechanical agitators into it. When a general power failure occurs, some pipes, tanks and equipment tend to get steady, dramatically reducing the usual turbulent environment, and therefore rapidly increasing the risk of massive settling of solids. The latter is unacceptable since it could lead to significant losses due the inability to run the processing plant for several hours, or even days. The way to avoid this issue is having operational protocols in place to rapidly empty the critical tanks and pipes (those unable to drain by gravity) when power fails, together with an adequate set of hydraulic works especially designed to handle these massive spills. This paper summarizes the best engineering practices successfully applied to the design of the hydraulic works for handling massive slurry spills, including feedback from actual operations.