Weir Minerals recently sold a KHD high pressure grinding roll (HPGR) to Goldrock Mines for installation in an Argentina heap leach gold mine.

After a hard fought competition by all major suppliers, Goldrock Mines awarded Weir Minerals North America an order for the supply of a roller press (RPS), or a high pressure grinding roll (HPGR) as it is known in the minerals industry. The scope of supply includes a RPS 16-170/180 HPGR, along with motors with variable speed controllers, and special tools.

Goldrock’s Lindero Project consists of a porphyry gold deposit located in northwestern Argentina and includes a shallow open pit mine, two stage conventional ore crushing, followed by a closed circuit HPGR crusher, conventional heap leaching, and a carbon absorption-desorption-recovering processing plant for precious metal recovery.

The KHD HPGR will process approximately 955 metric tons per hour (mt/h) for the gold heap leach process. It will operate in a closed circuit with edge recycling, to ensure adequately sized feed is provided to the heap leach pad.

High pressure grinding rolls are increasingly being used in comminution circuits instead of conventional crushers and AG or SAG mills due to their lower capital cost, lower energy consumption, lower maintenance requirements and enhanced downstream mineral recovery.

In April, 2013 Weir Minerals signed an exclusive and perpetual license with KHD Humboldt Wedag (KHD), giving Weir Minerals direct control over the design, manufacture, and distribution of high pressure grinding rolls in minerals processing applications using KHD technology.