Gold ore beneficiation process and specific equipment

1. Zinc powder replacement device

The zinc powder replacement process includes three stages: purification of mother liquor, deoxidation and displacement filtration. The suspended material in the gold-containing mother liquor is removed through a purification step.

The dissolved oxygen in the mother liquor hinders the recovery of gold through zinc replacement, so the oxygen in the mother liquor must be removed to ensure the smooth progress of gold recovery. The displacement filtration stage includes the addition of zinc powder and displacement operations. Once zinc powder is added to the mother liquor, the displacement reaction begins. And the final replacement and filtration of gold mud is completed through the replacement device.

Therefore, the zinc powder replacement device mainly includes a deoxidation tower, zinc powder feeder and replacement device.

 When operating the zinc powder replacement device, we should pay attention to the following points:

1. Observe whether the running pump is normal, and check the inlet pressure and leakage of the replacement and purification rack.

2. Pay attention to the air tightness of the zinc powder replacement system to ensure that deoxidation meets technical requirements. And determine the amount of mother liquid based on the reserve volume of mother liquid and dilute solution, which can reduce the fluctuation amplitude.

3. Since the replacement operation has strong continuity characteristics, it generally does not stop, otherwise it will affect the quality of the gold mud and the replacement effect. If necessary, the stoppage time cannot exceed four hours.

4. Regularly check the pulp condition of the submersible pump and start it in time after the pump tank is filled.

5. Perform patrol inspections to prevent the increase of dilute solution; check whether the liquid levels of the mother liquor tank and dilute solution tank meet the standards; check whether the water temperature and water level of the circulating water tank are normal.

2. Washing and thickening machine

The washing thickener is a professional gold recovery equipment for solid-liquid separation and washing of pulp after cyanidation. It is divided into two layers and three layers. It has the advantages of small floor space, energy saving, and simplified process flow. Continuous discharge reduces multiple cycles of liquid gold and allows for early recovery. At the same time, the pulp time in the thickener is reduced and the leaching rate is improved. This washing thickener achieves reverse washing, continuous operation, large volume and high washing efficiency. It occupies a small area, has a reasonable structure, and has low operation and maintenance costs.

The working principle of the washing and thickening machine is: the paper pulp is fed through the feed pipe, settles freely in the rake pulp, and gradually enters concentration through the pressure of the scraper. It gradually moves from the rake surface to the center of the pool, and enters the pool by gravity from the discharge port. On the next floor, water enters the bottom layer of the material washing distribution box, the bottom of the spillway flow distribution box enters the upper layer of the washing material, and is discharged from the overflow port on the first floor of the overflow weir. After washing, the bottom material is doubled.

3. Classic cyanide project cases and equipment

 Tanzania 1,200 tons/day gold processing project

 Processing flow: All slime gold cyanide processing technology, including thickening – leaching – desorption electrolysis – tailings dry stacking.

Equipment: double impeller leaching mixing tank, desorption electrolysis system, washing and concentrator

Malaysia 700 tons/day gold beneficiation production line

 Treatment process: crushing and classification – cyanidation and leaching – tailings dry stack – sewage treatment

Equipment: Wet energy-saving grid ball mill, wet energy-saving overflow ball mill, highly efficient and improved concentrator, double impeller leaching mixing tank, XPA high-lift wear-resistant rubber slurry pump, chamber filter press, XPA wear-resistant rubber slurry pump

 Zimbabwe 700 tons/day rock gold processing project

Treatment process: twice closed circuit grinding – gravity separation – concentration – cyanidation and leaching

Equipment: fixture, shaking table, hydrocyclone, double impeller leaching stirring tank, desorption electrolysis system