The Separation of Carbonaceous Matter from Refractory Gold Ore Using Multi-Stage Flotation: A Case Study

Abstract

As a pre-treatment method of refractory gold ore, carbonaceous matter (C-matter) flotation was investigated with multi-stage flotation by rougher, scavenger, and cleaner stages. Different dosages of kerosene and MIBC (4-Methyl-2-pentanol) were applied and the optimum dosage was selected by testing in each flotation stage. With the combination of each stage, four circuit designs were suggested, which were a single-stage rougher flotation (R), rougher-scavenger flotation (R+S), rougher-scavenger-scavenger cleaner flotation (R+S+SC), and rougher-rougher cleaner-scavenger-scavenger cleaner flotations (R+S+RC+SC). The results indicated that the scavenger flotation increased C-matter recovery but reduced C-matter grade compared with single-stage rougher flotation. Cleaning of the scavenger flotation concentrate improved C-matter grade significantly, but reduced recovery slightly. Cleaning of the rougher flotation concentrate achieved overall improved selectivity in flotation. A combination of rougher-scavenger flotation followed by cleaning of both concentrates (R+S+RC+SC) resulted in 73% C-matter recovery and a combined cleaner concentrate grade of 4%; the final tailings C-matter grade was 0.9%, where the C-matter remaining in the tailings was locked, and fine grained. The results demonstrate the need for the multi-stage flotation of C-matter from refractory gold ore to achieve selective separation and suggested the potential of C-matter flotation as the pre-treatment for efficient gold production.

Using Kerosene as an Auxiliary Collector to Recover Gold from Refractory Gold Ore Based on Mineralogical Characteristics

“…When the kerosene consumption was further increased to 2400 g/t, the Au grade in the concentrate was almost unchanged, and the Au recovery rate increased to 65.64%. The results show that the addition of kerosene improved the surface properties of sulfide ore, enhanced the adsorption of the collector to sulfide ore, and produced a synergistic effect [27,32]. The influence of kerosene consumption on the concentrate index and economic benefit was analyzed comprehensively, and the appropriate kerosene consumption was determined to be 2000 g/t.…”

“…Therefore, in order to reduce the amount of xanthate, in the flotation industry experiment, a more economical agent is often selected, and useful minerals are recovered collaboratively through a combination of drugs to achieve the purpose of reducing costs [23][24][25][26]. Kerosene has received a lot of attention in recent years as a common flotation collector and auxiliary collector, and some studies have shown that kerosene can have a synergistic effect with the sulfide ore collector to improve the recovery rate of gold [22,[27][28][29].…”