Outotec HIGmills; A Fine Grinding Technology

ABSTRACT Global ore grades are declining while commodity demands continue to increase. Ore bodies requiring treatment are becoming increasingly complex requiring a finer grind size for maximum mineral recovery and grade. The demand for a finer grind size has set new challenges especially for grinding technology.

Energy efficiency is a major driving force targeted for environmental sustainability and project viability. Fine grinding technology is utilized especially

in concentrate regrinding to liberate the valuable minerals after the first stage of concentration. Maintaining the correct particle size and particle size distribution of the regrind product is crucial for downstream process performance.

Outotec HIGmills™ being based on existing, well proven stirred milling technology provide modern, sophisticated, flexible and energy efficient grinding

solution for fine and ultra fine grinding. Outotec HIGmills™ offer the unique possibility for online control and optimization of regrind product particle size.

This paper describes the basis of this online control possibility and how this fine grinding technology can be implemented in minerals processing especially in regrinding applications. The main focus of this paper is to describe the flexibility of this grinding solution to respond the fluctuations in feed rate  tonnages as well as particle size fluctuations in concentrate regrinding.