Application of a combined inhibitor in flotation separation of associated gold-silver-lead-zinc sulfide ore

Abstract

The application discloses application of a combined inhibitor in associated gold-silver-lead-zinc sulfide ore flotation separation, wherein the combined inhibitor is a combination of zinc sulfate and methionine, and the mass ratio of the two combined is 2:1; the combined inhibitor is used to realize associated gold-silver-low-copper-lead-zinc polymetallic sulfide ore flotation separation in a low-alkali environment, has a good separation effect, high concentrate grade, effectively reduces the zinc content of lead concentrate, improves the gold and silver recovery rate in the lead concentrate, and has important significance for improving the quality and efficiency of associated gold-silver-low-copper-lead-zinc polymetallic sulfide ore flotation separation. In addition, the methionine in the combined inhibitor is a small-molecule organic substance, is non-toxic and non-polluting, and is easy to degrade, thereby avoiding the problems of traditional inhibitors, such as toxicity, environmental unfriendliness and human body unfriendliness. The combined inhibitor has small dosage, stable effect, and good process application prospect.

Description

TECHNICAL FIELD

[0001] The application relates to application of a combined inhibitor in flotation separation of associated gold-silver-lead-zinc sulfide ore, in particular to mixing zinc sulfate and methionine at a mass ratio of 2:1 as a combined inhibitor for sphalerite, and belongs to the technical field of mineral processing. BACKGROUND

[0002] Copper, lead and zinc, as common non-ferrous metals, play a vital role in the fields of aerospace, power, electronic components, ships and medical treatment. With the progress of science and technology and the development of economic construction, the demand for copper, lead and zinc is gradually expanding. Gold and silver, as common precious metals, are also increasingly in demand in production and life. Therefore, comprehensive recovery and utilization of associated gold-silver polymetallic sulfide ore is of great significance.

[0003] In the high-alkali process for inhibiting iron sulfide minerals (including pyrite and pyrrhotite) of polymetallic sulfide ore, lime is low in cost and good in inhibiting effect. However, when a large amount of lime is used, pipe slurry is hardened, pipes are blocked, flotation froth is sticky, inhibited sulfur is difficult to activate, and mineral processing wastewater is difficult to treat, and a series of problems occur. Therefore, it is necessary to select a method for realizing flotation separation of polymetallic sulfide ore in a low-alkali environment.

[0004] Associated gold-silver low-copper-lead-zinc polymetallic sulfide ore is mainly composed of galena, chalcopyrite, sphalerite and pyrite. Galena is the main carrier mineral of silver, and gold mainly exists in the form of sulfide inclusions in chalcopyrite, galena and pyrite.

[0005] The difficulties in ore dressing of the ore by using the existing flotation process are that (1) high-alkali sulfur inhibition leads to low recovery rates of associated precious metals gold and silver, and most of the precious metals are lost in tailings; and (2) the sphalerite inhibition effect is poor, and the lead concentrate contains high zinc, leading to zinc loss. The above problems seriously affect the economic benefits. SUMMARY

[0006] The application aims to provide application of a combined inhibitor in flotation separation of associated gold-silver-lead-zinc sulfide ore, the combined inhibitor is small in dosage, safe and environmentally friendly, and is a new sphalerite inhibitor. The combined inhibitor is combined with zinc sulfate at a ratio of 1:2 to inhibit sphalerite at low alkalinity, so that flotation separation of lead-zinc sulfide ore is realized.

[0007] The methionine in the combined inhibitor has the following structural formula:

[0008]

[0009] The combined inhibitor, which increases the silver content in lead concentrate and decreases the zinc content under low-alkali conditions, and decreases the silver content in zinc concentrate, thereby comprehensively improving the economic efficiency of the product, is applied in the flotation separation of associated gold, silver, lead, and zinc sulfide ores. The specific steps are as follows:

[0010] (1) Grind the mineral to be selected to a grinding concentration of 64% to 67% and grind until the particle size of less than 0.074 mm by mass accounts for 60-65%;

[0011] (2) Add lime, combined inhibitor and combined collector to the slurry after grinding in step (1) in sequence. After adjusting the slurry, carry out lead roughing to obtain lead roughing concentrate and lead roughing tailings respectively.

[0012] (3) The lead roughing tailings obtained in step (2) are subjected to two scavenging operations. Lime and combined collector are added in the first scavenging operation, and combined collector is added in the second scavenging operation. The concentrate from each scavenging operation is returned to the previous operation in sequence to form a closed loop. The final lead tailings are obtained after two scavenging operations.

[0013] (4) The lead roughing concentrate obtained in step (1) is subjected to three cleaning operations. Lime and combined inhibitors are added in the first and second cleaning operations, and only combined inhibitors are added in the third cleaning operation. The tailings of each cleaning operation are returned to the previous operation in sequence to form a closed loop. The final lead concentrate is obtained after three cleaning operations.

[0014] The combined collector is a combination of No. 25 black powder and aniline black powder, with a mass ratio of 3:1; the combined inhibitor is a combination of zinc sulfate and methionine, with a mass ratio of 2:1; lime is used as a pyrite inhibitor and pH adjuster.

[0015] In step (2), the amount of lime used is 1000-2000 g / t, the amount of combined inhibitor used is 700-1000 g / t, and the amount of combined collector used is 120-150 g / t.

[0016] In step (3), the amount of lime used in the first scavenging operation is 300-500 g / t, the amount of combined collector is 40-60 g / t, and the amount of combined collector used in the second scavenging operation is 10-20 g / t.

[0017] In step (4), the amount of lime used in the first fine cleaning operation is 300-500 g / t, the amount of combined inhibitor is 400-600 g / t, the amount of lime used in the second fine cleaning operation is 100-200 g / t, the amount of combined inhibitor is 200-300 g / t, and the amount of combined inhibitor is 100-200 g / t in the third fine cleaning operation.

[0018] The rough lead selection operation time is 4 min, the first and second sweep selection operation time is 4 min and 3.5 min respectively, and the first, second and third selection operation time is 3.5 min, 3 min and 2.5 min respectively.

[0019] In combination with the above scheme, the principles and beneficial effects of the present application are:

[0020] The present application uses No. 25 black medicine and aniline black medicine as a combined collector, which takes advantage of the strong collecting performance of No. 25 black medicine on copper and lead sulfide minerals under low alkali conditions and the selective collection of aniline black medicine on copper and lead in the presence of sphalerite and iron sulfide, which has a significant effect on improving the recovery rate of gold and silver. The combination of the two has the functions of coordination and promotion of collection and high selectivity. The combined depressant of sphalerite in the present application inhibits sphalerite under low alkali conditions to achieve efficient separation of lead-zinc sulfide ore. The amino and carboxyl groups in the methionine molecule have strong chelating ability with metal ions, and can also complex with zinc ions on the surface of sphalerite, exposing the hydrophilic carboxyl group to the outside to make the mineral surface hydrophilic, so that the sphalerite is inhibited. The Ca 2+ and Ca(OH) + can also be adsorbed on the surface of sphalerite to make it hydrophilic, and under alkaline conditions, zinc sulfate generates zincate ions adsorbed on the surface of sphalerite to inhibit sphalerite. In addition, methionine reacts with zinc sulfate first to produce zinc methionine adsorbed on the surface of sphalerite, which can also make the surface of sphalerite hydrophilic and be inhibited.

[0021] Compared with the prior art, the beneficial effects of the present application are:

[0022] (1) The present application provides a combined depressant and combined collector for lead-zinc sulfide ore flotation separation method under low alkalinity, which solves the environmental pollution and difficult treatment of beneficiation wastewater and a series of problems caused by traditional high alkali method.

[0023] (2) The present application improves the recovery rate of gold and silver in lead concentrate and reduces the zinc content of lead concentrate, thereby improving the economic benefits of the product. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The process flow chart of the present application. DETAILED DESCRIPTION

[0025] The present application will be further described in detail below in combination with specific embodiments, but the scope of protection of the present application is not limited to the content described.

[0026] Embodiment 1:

[0027] The associated gold, silver, low copper, lead and zinc polymetallic sulfide ore, galena is the main carrier mineral of silver, and gold mainly exists in the form of sulfide inclusions, mainly in chalcopyrite, galena and pyrite. The lead grade of raw ore is 3.07%, the zinc grade is 4.44%, the silver grade is 60.42g / t, and the gold grade is 0.21g / t. The useful minerals are mainly galena and sphalerite. The beneficiation is carried out by adopting the flow chart shown in the figure, and the specific steps are as follows: Figure 1 The specific steps are as follows:

[0028] Step (1), the ore to be selected is subjected to grinding treatment, and the grinding quality concentration is 64%, and the mineral particle size after grinding is 60% of-200 mesh;

[0029] Step (2), lime, combined depressant and combined collector are added in sequence to the ore slurry after grinding in step (1), and the slurry is stirred, and then lead roughing is carried out, and lead roughing concentrate and lead roughing tailings are obtained;

[0030] Step (3), the lead roughing tailings obtained in step (2) are subjected to two times of scavenging operation, lime and combined collector are added in the first scavenging operation, and combined collector is added in the second scavenging operation, and the concentrate of each scavenging operation is returned to the upper operation in sequence to form a closed loop, and the final lead tailings are obtained after two times of scavenging;

[0031] Step (4), the lead roughing concentrate obtained in step (2) is subjected to three times of concentration operation, lime and combined depressant are added in the first and second concentration operations, and combined depressant is added in the third concentration operation, and the tailings of each concentration operation are returned to the upper operation in sequence to form a closed loop, and the final lead concentrate is obtained after three times of concentration operation;

[0032] The combined collector is a combination of No. 25 black medicine and aniline black medicine, and the mass ratio of the two is 3:1; the combined depressant is a combination of zinc sulfate and methionine, and the mass ratio of the two is 2:1; lime is used as a pyrite depressant and a pH adjuster.

[0033] The amount of lime used in step (2) is 2000g / t, the amount of combined depressant is 1000g / t, and the amount of combined collector is 150g / t.

[0034] In step (3), the amount of lime used in the first scavenging operation is 500g / t, and the amount of combined collector is 60g / t, and the amount of combined collector used in the second scavenging operation is 20g / t.

[0035] In step (4), the amount of lime used in the first concentration operation is 500g / t, and the amount of combined depressant is 600g / t, the amount of lime used in the second concentration operation is 200g / t, and the amount of combined depressant is 300g / t, and the amount of combined depressant used in the third concentration operation is 150g / t.

[0036] The flotation time is 4 min for roughing, 4 min and 3.5 min for the first, second and third scavenging, respectively, and 3.5 min, 3 min and 2.5 min for the first, second and third cleaning, respectively.

[0037] The reagent system of the above experiment is shown in Table 1, the lead and zinc experimental results are shown in Table 2, and the gold and silver experimental results are shown in Table 3.

[0038] According to the above experimental procedure, the amount of lime is changed to 6000 g / t for roughing operation, and the rest of the reagent system remains unchanged for the experiment. The experimental reagent system is shown in Table 1, the lead and zinc experimental results are shown in Table 2, and the gold and silver experimental results are shown in Table 3.

[0039] Table 1. Reagent system of Example 1, Comparative Example 1 and Comparative Example 2, unit (g / t)

[0040]

[0041] Table 2. Experimental results of lead and zinc of Example 1, Comparative Example 1.

[0042]

[0043] Table 3. Experimental results of gold and silver of Example 1, Comparative Example 1.

[0044]

[0045] From Tables 1, 2 and 3, it can be seen that using zinc sulfate + methionine as an inhibitor under low alkali conditions can obtain a lead concentrate with a lead grade of 71.49%, a recovery rate of 90.59%, a silver grade of 1147.65 g / t, a silver recovery rate of 73.89%, a gold grade of 2.21 g / t, a gold recovery rate of 40.94%, and a zinc content of 5.69%. Under high alkali conditions, using this scheme for testing found that although high alkali conditions improved the quality of the lead concentrate, the zinc content of the lead concentrate increased, and the addition of a large amount of lime inhibited most of the pyrite, resulting in part of the gold and part of the silver also being inhibited with the pyrite, greatly limiting the recovery of gold and silver.

[0046] Example 2

[0047] A certain associated silver low copper lead-zinc polymetallic sulfide ore in Yunnan, galena is the main carrier mineral of silver. The lead grade of the raw ore is 1.58%, the zinc grade is 2.03%, and the silver grade is 27.41 g / t. The separation is carried out by using the flowchart shown in the figure, and the specific steps are as follows: Figure 1 The specific steps are as follows:

[0048] Step (1), the to-be-selected mineral is subjected to grinding treatment, and the grinding quality concentration is 67%, and the mineral particle size after grinding is 65% for -200 mesh;

[0049] Step (2), lime, combined depressant and combined collector are added to the ground ore slurry of step (1) in turn to perform rough lead separation, and rough lead concentrate and rough lead tailings are obtained respectively;

[0050] Step (3), the rough lead tailings obtained in step (2) are subjected to two times of scavenging operation, lime and combined collector are added in the first time of scavenging operation, and combined collector is added in the second time of scavenging operation, and the concentrate of each time of scavenging operation is returned to the previous operation in turn to form a closed loop, and the final lead tailings are obtained after two times of scavenging operation;

[0051] Step (4), the rough lead concentrate obtained in step (2) is subjected to three times of cleaning operation, lime and combined depressant are added in the first and second times of cleaning operation, and combined depressant is added in the third time of cleaning operation, and the tailings of each time of cleaning operation is returned to the previous operation in turn to form a closed loop, and the final lead concentrate is obtained after three times of cleaning operation;

[0052] The combined collector is a combination of No. 25 black medicine and aniline black medicine, and the mass ratio of the two is 3:1; the combined depressant is a combination of zinc sulfate and methionine, and the mass ratio of the two is 2:1; lime is used as a pyrite depressant and a pH adjuster.

[0053] In step (2), the amount of lime is 1500g / t, the amount of combined depressant is 800g / t, and the amount of combined collector is 130g / t.

[0054] In step (3), the amount of lime in the first time of scavenging operation is 400g / t, and the amount of combined collector is 50g / t, and the amount of combined collector in the second time of scavenging operation is 15g / t.

[0055] In step (4), the amount of lime in the first time of cleaning operation is 400g / t, and the amount of combined depressant is 500g / t, the amount of lime in the second time of cleaning operation is 150g / t, and the amount of combined depressant is 250g / t, and the amount of combined depressant in the third time of cleaning operation is 150g / t.

[0056] The flotation time is 4min for rough separation, 4min, 3.5min and 3.5min, 3min and 2.5min for the first, second and third times of scavenging operation, and the first, second and third times of cleaning operation respectively.

[0057] The above experimental reagent system is shown in Table 4, and the lead-zinc experimental results are shown in Table 5.

[0058] Comparative Example 2

[0059] According to the above experimental procedure, the combined depressant is changed to zinc sulfate + sodium sulfite, the experimental reagent system is shown in Table 4, and the experimental results are shown in Table 5.

[0060] Table 4. The dosage regimen of Example 2, Comparative Example 2, unit (g / t)

[0061]

[0062]

[0063] Table 5. Experimental results of Example 2, Comparative Example 2.

[0064]

[0065] From Table 4, Table 5, it can be seen that using zinc sulfate + methionine as an inhibitor under low alkali conditions can obtain a lead concentrate with a lead grade of 65.32%, a recovery rate of 93.85%, a silver grade of 885.12 g / t, a silver recovery rate of 73.30%, and a zinc content of 4.76%. The use of zinc sulfate + sodium sulfite combination inhibits the use of lime, and at the same time, the quality and recovery rate of lead concentrate are reduced, which also leads to a decrease in silver recovery rate. The scheme of zinc sulfate + methionine improves the production efficiency, and the technical scheme is feasible.

[0066] Example 3

[0067] A certain associated gold and silver lead-zinc polymetallic sulfide ore in Yunnan, galena is the main carrier mineral of silver, and gold mainly exists in the form of sulfide inclusions, mainly in chalcopyrite, galena and pyrite. The lead grade of raw ore is 1.98%, the zinc grade is 1.54%, the silver grade is 51.67 g / t, and the gold grade is 0.18 g / t. The process shown in the flow chart is used for separation, and the specific steps are as follows: Figure 1 The specific steps are as follows:

[0068] Step (1), the selected mineral is subjected to grinding treatment, and the grinding quality concentration is 65%, and the mineral particle size after grinding is 63% of -200 mesh;

[0069] Step (2), lime, combined inhibitor and combined collector are sequentially added to the ore slurry after grinding in step (1) to adjust the pulp, and then lead roughing is carried out, to obtain lead roughing concentrate and lead roughing tailings, respectively;

[0070] Step (3), the lead roughing tailings obtained in step (2) are subjected to two times of scavenging operation, lime and combined collector are added in the first scavenging operation, and combined collector is added in the second scavenging operation, and the concentrate of each scavenging operation is returned to the upper operation in sequence to form a closed loop, and the final lead tailings are obtained after two times of scavenging;

[0071] Step (4), the lead roughing concentrate obtained in step (2) is subjected to three times of cleaning operation, lime and combined depressant are added in the first and second cleaning operation, and only combined depressant is added in the third cleaning operation, and the tailings of each cleaning operation are returned to the previous operation in sequence to form a closed circuit, and the final lead concentrate is obtained after the three times of cleaning operation;

[0072] The combined collector is a combination of No. 25 black medicine and aniline black medicine, and the mass ratio of the two is 3:1; the combined depressant is a combination of zinc sulfate and methionine, and the mass ratio of the two is 2:1; lime is used as a pyrite depressant and a pH regulator.

[0073] The amount of lime used in step (2) is 1000g / t, the amount of combined depressant is 700g / t, and the amount of combined collector is 120g / t.

[0074] The amount of lime used in the first cleaning operation in step (4) is 300g / t, and the amount of combined depressant is 400g / t, the amount of lime used in the second cleaning operation is 100g / t, and the amount of combined depressant is 200g / t, and the amount of combined depressant used in the third cleaning operation is 100g / t.

[0075] The amount of lime used in the first cleaning operation in step (4) is 300g / t, and the amount of combined depressant is 400g / t, the amount of lime used in the second cleaning operation is 100g / t, and the amount of combined depressant is 200g / t, and the amount of combined depressant used in the third cleaning operation is 100g / t.

[0076] The flotation time is 4min for roughing, 4min and 3.5min for the first, second and third scavenging, respectively, and 3.5min, 3min and 2.5min for the first, second and third cleaning, respectively.

[0077] The reagent system of the above experiment is shown in Table 6, the lead and zinc experimental results are shown in Table 7, and the gold and silver experimental results are shown in Table 8.

[0078] Comparative Example 3

[0079] According to the above experimental procedure, the depressant for sphalerite is changed to zinc sulfate + sodium metabisulfite, the reagent system of the experiment is shown in Table 6, the lead and zinc experimental results are shown in Table 7, and the gold and silver experimental results are shown in Table 8.

[0080] Table 6 Reagent system of Example 3 and Comparative Example 3, unit (g / t)

[0081]

[0082] Table 7. Experimental results of lead and zinc of Example 3 and Comparative Example 3.

[0083]

[0084] Table 8. Experimental results of gold and silver of Example 3 and Comparative Example 3.

[0085]

[0086] From Table 7 and Table 8, it can be seen that using zinc sulfate + methionine as the depressor under low alkaline conditions can obtain a lead concentrate with a lead grade of 72.32%, a lead recovery of 93.87%, a silver grade of 1468.34 g / t, a silver recovery of 73.03%, a gold grade of 2.88 g / t, a gold recovery of 41.12%, and a zinc content of 2.85%. Compared with using zinc sulfate + sodium pyrosulfite, the gold and silver recoveries are improved under the condition of ensuring the quality of the lead concentrate, which has great significance for production practice.

[0087] In summary, using zinc sulfate + methionine as the combined depressor to depress sphalerite can realize effective separation of gold, silver, low copper, lead and zinc polymetallic sulfide ore under low alkaline conditions. The combined depressor is green and environmentally friendly, can be naturally degraded, is friendly to the environment, and avoids a series of hazards caused by the use of a large amount of lime under low alkaline conditions.

[0088] The above only describes the preferred embodiments of the present application, and does not limit the present application in any form. Any simple modification, equivalent change and modification made according to the technical essence of the present application to the above embodiments are within the scope of the technical solutions of the present application.

Claims

1. The application of a combined inhibitor in the flotation separation of associated gold, silver, lead, and zinc sulfide ores, characterized in that, The specific steps of the flotation separation are as follows: (1) Grind the mineral to be selected to a grinding concentration of 64% to 67% by weight until the particle size of less than 0.074 mm accounts for 60-65% by weight; (2) Add lime, combined inhibitor and combined collector to the slurry after grinding in step (1) in sequence. After adjusting the slurry, carry out lead roughing to obtain lead roughing concentrate and lead roughing tailings respectively. The amount of lime is 1000~2000 g / t, the amount of combined inhibitor is 700~1000 g / t, and the amount of combined collector is 120~150 g / t. (3) The lead roughing tailings obtained in step (2) are subjected to two scavenging operations. Lime and combined collector are added in the first scavenging operation, and combined collector is added in the second scavenging operation. The concentrate from each scavenging operation is returned to the previous operation in sequence to form a closed loop. The final lead tailings are obtained after two scavenging operations. (4) The lead roughing concentrate obtained in step (1) is subjected to three cleaning operations. Lime and combined inhibitors are added in the first and second cleaning operations, and only combined inhibitors are added in the third cleaning operation. The tailings of each cleaning operation are returned to the previous operation in sequence to form a closed loop. The final lead concentrate is obtained after three cleaning operations. The combined collector is a combination of No. 25 black powder and aniline black powder, with a mass ratio of 3:1; the combined inhibitor is a combination of zinc sulfate and methionine, with a mass ratio of 2:1; lime is used as a pyrite inhibitor and pH adjuster.

2. The application of the combined inhibitor according to claim 1 in the flotation separation of associated gold, silver, lead, and zinc sulfide ores, characterized in that: In step (3), the amount of lime used in the first scavenging operation is 300~500 g / t, the amount of combined collector is 40~60 g / t, and the amount of combined collector used in the second scavenging operation is 10~20 g / t.

3. The application of the combined inhibitor according to claim 1 in the flotation separation of associated gold, silver, lead, and zinc sulfide ores, characterized in that: In step (4), the amount of lime used in the first fine cleaning operation is 300~500 g / t and the amount of combined inhibitor is 400~600 g / t. In the second fine cleaning operation, the amount of lime used is 100~200 g / t and the amount of combined inhibitor is 200~300 g / t. In the third fine cleaning operation, the amount of combined inhibitor is 100~200 g / t.

4. The application of the combined inhibitor according to claim 1 in the flotation separation of associated gold, silver, lead, and zinc sulfide ores, characterized in that: The lead roughing operation takes 4 minutes, the first and second sweeping operations take 4 minutes and 3.5 minutes respectively, and the first, second and third fine cleaning operations take 3.5 minutes, 3 minutes and 2.5 minutes respectively.

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