Flotation and dump leaching combined gold extraction process

Abstract

The invention discloses a flotation and dump leaching combined gold extraction process for improving the gold extraction rate. Oxidized heavier minerals which are wrapped by limonite in a traditional flotation process, cannot float upwards and are large in specific gravity are recycled in a dump leaching mode after being subjected to gravity concentration and enrichment through the spiral chute, so that the effect of comprehensive utilization of resources is achieved, the grade of tailings is reduced as much as possible, and the mineral separation extraction rate is increased as much as possible.

Description

Technical field:

[0001] The invention relates to a flotation and heap leaching combined gold extraction process, belonging to the field of ore dressing. Background technology:

[0002] Gold exists in nature in a single form, but is generally densely associated with sulfides. Slightly oxidized ores that are not oxidized or have an oxidation rate of less than 30% in sulfide deposits are called sulfide ores, while those with an oxidation rate of more than 30% are called oxidized ores. Natural gold and sulfide ores are easily floated minerals and are easily captured by xanthate collectors. Flotation technology is used to extract gold. The surface of gold particles in oxidized ores is often contaminated or covered by iron oxides, and the floatability is poor. For low-grade oxidized gold ores, heap leaching technology is used to recover them.

[0003] The traditional flotation process can only float the metals that coexist with sulfides through foam, while those heavily oxidized minerals do not have sulfides as carriers and most of them are lost in the tailings. Summary of the invention:

[0004] The object of the present invention is to provide a flotation and heap leaching combined gold extraction process for improving the gold extraction rate.

[0005] The present invention is implemented by the following technical scheme: a gold beneficiation process, which comprises the following steps:

[0006] 001. Crushing and grinding the gold-containing sulfide ore to obtain gold ore powder;

[0007] 002. Place the gold ore powder in a flotation tank for slurry preparation to obtain ore slurry;

[0008] 003. Roughing the slurry obtained in step 002 to obtain coarse gold concentrate and roughing tailings;

[0009] 004. The coarse gold concentrate is subjected to flotation to obtain gold concentrate and selected tailings;

[0010] 005. Sweep the rougher tailings to obtain scavenged ore and scavenged tailings;

[0011] 006. The tailings and the scavenged tailings are returned to step 002 together;

[0012] 007. Reselect the scavenged tailings to obtain heavy sand;

[0013] 008. Crushing the gold-containing oxide ore to obtain crushed material;

[0014] 009. Mix and stir the heavy sand and the gold ore particles to obtain heap leaching particles;

[0015] 010. Heaping the heap leaching particles to form an ore pile;

[0016] 011. Spray the leaching solution onto the top of the ore pile and obtain the heap leaching solution by percolation;

[0017] 012. Collect heap leach liquid to extract gold leached from the ore.

[0018] Preferably, in step 001, the gold-containing sulfide ore is ground.

[0019] Preferably, in step 002, the slurry concentration is 40% to 45% by mass.

[0020] Preferably, water glass and sodium hexametaphosphate g / t slurry preparation and activator sodium sulfide 45g / t are added to the slurry in sequence according to the mass ratio of gold ore powder before slurry preparation, and the mixture is stirred for activation for 3 to 5 minutes; collector C745a 1.5g / t, isopentyl xanthate 2.45g / t and butyl ammonium black medicine 1.05g / t are added to the slurry after stirring and activation in sequence according to the mass ratio of gold ore powder before slurry preparation, and the mixture is stirred evenly.

[0021] Preferably, in step 003, the rough selection is performed for 2 to 3 minutes.

[0022] Preferably, in step 007, the scavenged tailings are reselected by a spiral chute.

[0023] Preferably, in step 008, the gold-containing oxide ore is crushed to ≤10 mm.

[0024] Preferably, in step 011, the spray leaching liquid is a green and environmentally friendly gold leaching agent solution, and the heap leaching cycle is 50 to 60 days.

[0025] Preferably, in step 012, the process of extracting ore with heap leaching liquid is an activated carbon adsorption process.

[0026] Advantages of the present invention: Compared with the traditional flotation process, the present invention uses a spiral chute to recover the heavier oxidized minerals that are wrapped by limonite and cannot float in the traditional flotation process and have a relatively large specific gravity through heap leaching after gravity selection and enrichment, and does not discharge them into the tailings pond, so as to achieve the effect of comprehensive resource utilization, reduce the tailings grade as much as possible, and improve the mineral processing extraction rate. Specific implementation method:

[0027] Embodiment: 1. Gold beneficiation process, comprising the following steps:

[0028] 001. Crushing and grinding the gold-containing sulfide ore to -200 mesh accounting for 90% to obtain gold ore powder;

[0029] 002. Place the gold ore powder in a flotation tank and adjust the slurry according to the mass percentage of 40% to 45% to obtain a pulp; according to the mass ratio of the gold ore powder before the slurry adjustment, add water glass and sodium hexametaphosphate 7.5g / t, activator sodium sulfide 45g / t to the pulp, and stir and activate for 3 to 5 minutes; according to the mass ratio of the gold ore powder before the slurry adjustment, add collector C745a 1.5g / t, isopentyl xanthate 2.45g / t, butyl ammonium black medicine 1.05g / t to the pulp after stirring and activation, and stir evenly;

[0030] 003. Roughing the slurry obtained in step 002 for 2 to 3 minutes to obtain a coarse gold concentrate and roughing tailings;

[0031] 004. The coarse gold concentrate is subjected to flotation to obtain gold concentrate and selected tailings;

[0032] 005. Sweep the rougher tailings to obtain scavenged ore and scavenged tailings;

[0033] 006. The tailings and the scavenged tailings are returned to step 002 together;

[0034] 007. The scavenging tailings are re-selected through a spiral chute to obtain heavy sand; 008. The gold-containing oxide ore is crushed to ≤10mm to obtain crushed material;

[0035] 009. Mix and stir the heavy sand and the gold ore particles to obtain heap leaching particles;

[0036] 010. Heaping the heap leaching particles to form an ore pile;

[0037] 011. Spray the leaching solution onto the top of the ore pile. The spraying leaching solution is a green and environmentally friendly gold leaching agent solution. The heap leaching cycle is 50 to 60 days. The heap leaching solution is obtained by filtration.

[0038] 012. Collect the heap leaching liquid and use the activated carbon adsorption process to extract the gold leached from the ore.

[0039] Working principle: Since pyrite becomes limonite after oxidation, the floatability is poor, and part of the encapsulated gold cannot be enriched and recovered by flotation process. After gravity separation in spiral chute 3, this part of limonite with a larger specific gravity is re-selected and enriched. The gold grade after enrichment reaches more than 0.8g / t, and the yield of gravity separation concentrate reaches about 10%. The leaching rate of the gravity separation concentrate heap leaching test in the laboratory reaches 50%. The amount of metal that can be recovered by heap leaching of heavy sand after gravity separation is 0.8g / t*50%*10%=0.04g. Calculated based on the gold grade of the original ore of 1.2g / t, the mineral processing extraction rate can be increased by about 3%.

Claims

1. A gold beneficiation process, characterized in that: It includes the following steps:

001. Crushing and grinding the gold-containing sulfide ore to obtain gold ore powder; 002. Place the gold ore powder in a flotation tank for slurry preparation to obtain ore slurry; 003. Roughing the slurry obtained in step 002 to obtain coarse gold concentrate and roughing tailings; 004. The coarse gold concentrate is subjected to flotation to obtain gold concentrate and selected tailings; 005. Sweep the rougher tailings to obtain scavenged ore and scavenged tailings; 006. The tailings and the scavenged tailings are returned to step 002 together; 007. Reselect the scavenged tailings to obtain heavy sand; 008. Crushing the gold-containing oxide ore to obtain crushed material; 009. Mix and stir the heavy sand and the gold ore particles to obtain heap leaching particles; 010. Heaping the heap leaching particles to form an ore pile; 011. Spray the leaching solution onto the top of the ore pile and obtain the heap leaching solution by percolation; 012. Collect heap leach liquid to extract gold leached from the ore.

2. The gold beneficiation process according to claim 1, characterized in that: In step 001, the gold-containing sulfide ore is ground.

3. The gold beneficiation process according to claim 1, characterized in that: In step 002, the slurry concentration is 40% to 45% by mass.

4. The gold beneficiation process according to claim 2, characterized in that: According to the mass ratio of gold ore powder before slurrying, water glass and sodium hexametaphosphate g / t and activator sodium sulfide 45g / t are added to the slurry in sequence for slurrying, and activated by stirring for 3 to 5 minutes; according to the mass ratio of gold ore powder before slurrying, collector C745a 1.5g / t, isopentyl xanthate 2.45g / t and butyl ammonium black medicine 1.05g / t are added to the slurry after stirring and activation in sequence, and stirred evenly.

5. The gold beneficiation process according to claim 1, characterized in that: In step 003, rough selection is performed for 2 to 3 minutes.

6. The gold beneficiation process according to claim 1, characterized in that: In step 007, the scavenged tailings are reselected through a spiral chute.

7. The gold beneficiation process according to claim 1, characterized in that: In step 008, the gold-containing oxide ore is crushed to ≤10 mm.

8. The gold beneficiation process according to claim 1, characterized in that: In step 011, the spray leaching liquid is a green and environmentally friendly gold leaching agent solution, and the heap leaching cycle is 50 to 60 days.

9. The gold beneficiation process according to claim 1, characterized in that: In step 012, the process of extracting ore with heap leaching liquid is an activated carbon adsorption process.