Project Background

In 2017, Our Company formally signed a contract with the project company for a 500tpd gold ore dressing plant project to provide a solution. Hengtailong pointed out that due to the inclusion of granular gold, some of the granular gold was lost during the sampling, sample preparation, and subtraction processes in the original geological exploration process. Sampling and analysis, and pay attention to the bonding of particle gold on the surface of the equipment during the sample preparation process.

(Project site of Congo 500tpd gold ore dressing plant)

Hengtailong's rigorous attitude, accurate data and customized plant selection services greatly appreciated the customers of this project. At the same time, customers also appreciated Hengtailong's strong brand strength, mining project solutions, advanced and reliable equipment quality and excellent service Fully affirmed, which led to this cooperation. In the end, Hengtailong Company achieved the formal commissioning of the project in only 10 months (including transportation and customs clearance for 2 months), and the economic benefits of the plant selection were considerable.

(Project site of Congo 1000tpd gold ore dressing plant)

Project Overview

The nature of the ore: The ore of the project is mainly oxidized ore, 80% of the ore is powdered clay ore, containing granular gold, the average grade of the ore is 1.0g / t, the impurity element is very little, gold is the only recyclable element, and the ore is easy to select.

Processing capacity: 500tpd

Proposal : a section of closed-circuit grinding classification-re-election-cyanide gold extraction-desorption electrolysis, smelting-tailings treatment. 

(Project site of Congo 1000tpd gold ore dressing plant)

Hengchang scheme

1. the original ore

Most of the original ores in this project are fine-grained ore deposits with a finer particle size and do not need to be crushed. The original ore yard is set up, and the incoming materials can be directly fed to the original ore bin, or unloaded to the original ore yard for storage, and then fed to the steel silo with a forklift. Go to the ball mill for grinding.

2. Grinding classification + Gravity separation

The ore transported by the belt conveyor is fed into the ball mill for a period of grinding. The ball mill discharge ore is sent to the jig for re-election by the slurry pump, and the re-selected coarse concentrate flows to the 6S shaker for selection. Then it flows to another 6S shaker for selection to obtain granular gold. The tailings in the shaker flow to the pump box, which is transported by the slurry pump to the ball mill for grinding, and the tailings of the jig are transported to the cyclone group by the slurry pump Classification, the grit of the cyclone is returned to the ball mill for re-grinding, and then the self-flowing overflow removes the sieves and removes impurities. Then it is classified by the two-stage cyclone. Other overflows will flow to the thickener for concentration.

3. Concentration, cyanide leaching

The underflow concentration of the thickener is concentrated to about 40%, and the slurry pump is driven into the double-impeller high-efficiency leaching tank for leaching and carbon adsorption, and the Roots blower is used to fill the leaching tank with air, and NaCN is added to make the slurry, reagent and air sufficient Mixed reaction.

The gold in the ore reacts with NaCN in an alkaline environment to generate gold cyanide ions. The gold enters the solution and is adsorbed by activated carbon. During production, the carbon is reversely extracted, and the saturated gold-carrying carbon is extracted from the leaching tank, fed into the carbon-lifting sieve, the ore pulp under the sieve is returned to the leaching tank, and the gold-carrying carbon on the sieve is hydraulically transported to the carbon storage tank for carbon washing. The clean saturated gold-loaded carbon is then sent to the desorption electrolysis system for gold extraction, and the electrolyzed gold sludge is smelted in a high-frequency gold melting furnace to obtain the final gold.

4. Activated carbon regeneration

After using activated carbon several times, its activity will be weakened and its adsorption capacity for gold will be reduced. In order to restore its activity to a certain extent and ensure its recycling, the de-golded carbon needs to be regenerated. There are two methods of activated carbon regeneration: one is acid cleaning regeneration, and the other is high temperature activation regeneration.

5. Tailings treatment

The cyanide tailings are transported to the tailings pond by a slurry pump for sedimentation. The tailings are piled up in the pond and the clarified water is returned to the production return tank for recycling to achieve zero discharge of production sewage.

Project Benefits

1. From beneficiation testing, mine design, equipment manufacturing and procurement, packaging and shipping, to installation and commissioning, worker training, standard production, to project management, mine operation, all contracted by Hengchang Company Solution: The project has high construction efficiency, short construction period, and quick commissioning.

Since the signing of the contract, it took only 8 months (including transportation and customs clearance for 2 months) for Hengchang Mine Equipment to realize the formal commissioning of the gold mine project.

2. The design scheme is adapted to local conditions and the process is advanced and reasonable

✦ Open-pit mining is adopted, because the ore is in the form of sand powder, so no blasting is needed during mining, and it is directly excavated and loaded with trucks to the processing plant, which greatly reduces the mining cost.

✦ 80% of the ore in the project is powdered clay ore, and the original ore contains 25 to 30% water. On the one hand, Hengchang Company solved the problem of easy plugging and ore feeding of powdered clay mines, on the other hand, it adopted the process of re-selection + cyanidation, specially strengthened the re-selection operation and grinding process, and recovered part of the re-selection operation first. Granular gold reduces the grade of gold entering the leaching operation, thereby reducing the consumption of chemicals and the production cost of mineral processing.

✦ The entire plant is built according to the terrain, and the buildings are relatively concentrated. The equipment configuration in each plant of the concentrator takes into account the main pulp to achieve self-flow as much as possible. The operation of similar equipment is relatively centralized, which is convenient for operation and management.

3. Green and environmentally friendly

✦ The leaching agent used in this project adopts a low-toxic and environmentally friendly leaching agent that can replace sodium cyanide. The consumption of the agent is low and the cost is low. At the same time, the index remains the same as that of sodium cyanide.

✦ The production drainage of the concentrator (the overflow water of the thickener and the clarified backwater of the tailings pond) are returned to the production backwater tank for recycling, so as to achieve zero discharge of production sewage.

Project results

At present, the 500tpd gold ore beneficiation plant project has been successfully put into operation, the entire beneficiation plant is running stably, the equipment quality is reliable, and the beneficiation indicators and economic benefits have reached expectations. Hengchang's professional factory selection service strength has also been strongly affirmed and recognized by customers of the project.