Audit and Optimization Services - Gravity Gold

The industry standard gravity recoverable gold (GRG) test provides benchmark. ore characteristics. The laboratory test includes three gravity stages with intermediate grinding. 

Each of the three test stages reveals coarse, medium and fine gold response. 

In industrial practice, at high throughout conditions, the gravity separation for coarse gold will differ from that of fine gold and production expectations should account for that.

Grinding efficiency remains at the core of every circuit.

It is rarely an issue that gravity circuits affect SAG, Ball or Impact Mills (VSI) as long as basic design and operating considerations are observed.

Hydrocyclone efficiency is a strong contributor to grinding and gravity optimization.

The cyclone U/F to O/F particle size distribution and gold grade ratio are simple and practical metrics that help uncover gravity opportunities. 

Screen classification guards the gravity concentrator from excessive wear, but classification size has little impact on metal recovery.

While centrifugal gravity concentrators operate best in closed circuits with hydro classification (Cyclone U/F or Cyclone Feed), open circuit options (Cyclone O/F) exist in certain applications.

Treating a fraction of the circulating load is sufficient where whole-ore cyanidation follows.

Treating multiple streams and large fractions thereof is essential for gravity-only plants, where combinations of low-G and high-G gravity methods may generate the best outcome.

Batch concentrators prove inherently difficult to optimize through sampling campaigns. Best practice operations and maintenance training are practical optimization pathway.

A comprehensive audit includes downstream gravity upgrading (tabling) or intensive cyanidation assessment. HiGrade is experienced in best-practice gold room operations.

The audit concludes in the form of a concise report, with practical optimization recommendations., focused on improved metal recovery and cost effective maintenance.