Experimental study on a fine-grained encapsulated refractory gold deposit in Liaoning Province

The stage grinding and selection process was proposed and optimized to address the high energy consumption and severe mudization caused by full-flow ultra-fine grinding of a low-grade fine-grained encapsulated refractory gold deposit in Liaoning. The test results show that in the optimal conditions of the grinding fineness of −0.074 mm accounting for 70 %, pulp concentration of 33 %, isopentyl sodium xanthate 80 g/t and butyl ammonium black medicine 20 g/t as the combined collectors, and BK204 8 g/t as the frother, the crude concentrate is reground （−0.038 mm accounting for 88.9 %）. The final grade of gold concentrate is 40.47 g/t and the recovery is 82.56 %. Product verification confirms that the dense encapsulation of sulfides is effectively broken by the stage grinding and selection, thus achieving efficient dissociation of gold. This study provides reliable technical support for the efficient and low-consumption development of similar low-grade fine-grained encapsulated refractory gold deposits.