A method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore

Abstract

This invention discloses a method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore. The method employs a physical desliming-rapid flotation-coarse grinding-flotation-zinc concentrate regrinding followed by desulfurization process. Desliming is carried out using a combination of strong dispersion stirring, weak stirring, and weak stirring siphon desliming, effectively removing fine mud from the zinc oxide and reducing zinc loss in the mud. A portion of the coarse, easily floatable zinc oxide particles is then rapidly selected as high-quality zinc oxide concentrate. The incompletely liberated zinc oxide is further processed by grinding followed by flotation. The high-quality zinc oxide concentrate produced by rapid flotation is combined with the low-quality zinc oxide concentrate obtained after desulfurization to form a qualified zinc concentrate. This invention features a simple process flow, low cost, and wide applicability, achieving a zinc oxide recovery rate of 72-75%. It shows promising application prospects for the recovery of zinc oxide with high sulfur content.

Description

Technical Field

[0001] This invention relates to the field of metallurgical technology, specifically a method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore. Background Technology

[0002] Zinc recovery from zinc oxide resources has always been a challenging research area in mineral processing. The difficulties in zinc oxide recovery stem from several factors: 1. Zinc oxide contains a large amount of slime, including primary and secondary slime. This slime not only consumes significant amounts of beneficiation reagents, increasing beneficiation costs, but also significantly impacts ore selectivity, hindering the normal separation of coarse particles. 2. During desliming, zinc loss is inevitable, requiring a balance between desliming yield, zinc loss rate, and the impact on subsequent flotation. 3. The selection, dosage, and timing of the addition of modifiers and collectors are crucial for zinc recovery; otherwise, the recovery effect will be unsatisfactory. 4. Controlling the efficiency of zinc oxide beneficiation operations is extremely important and critical. Metal content is easily lost in the middlings during beneficiation, resulting in unsatisfactory final concentrate grade and recovery rate. 5. For zinc oxide with high sulfur content, sulfur is a major factor affecting the final concentrate quality, leading to substandard concentrate quality.

[0003] Because the actual production of lead-zinc oxide mines involves large quantities of zinc oxide reagents, resulting in high reagent costs, poor concentrate quality, complex or improper desliming processes, and unsatisfactory recovery effects, the profit margin for zinc oxide recovery is small. Some mines even abandon zinc oxide recovery altogether. This portion of zinc oxide contains 2-5% zinc, and in some mines, the zinc oxide grade is even higher. If this portion of zinc oxide is not recovered and is directly pumped to tailings ponds for storage, it results in a serious waste of mineral resources.

[0004] Currently, the main methods for recovering zinc oxide from flotation tailings of zinc oxide ore are gravity separation and flotation. Gravity separation primarily uses shaking tables, but the fine particle size of zinc oxide flotation tailings results in low zinc recovery rates. Flotation is the most common method, mainly including sulfide ammonium salt flotation, sulfide xanthate flotation, fatty acid flotation, and flocculation flotation. Zinc oxide ore differs from zinc sulfide; its composition and structure are more complex, and different ores require different beneficiation methods. To maximize flotation performance, a suitable process should be selected based on the properties and composition of the zinc oxide ore. Summary of the Invention

[0005] The purpose of this invention is to provide a method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore. The method employs a physical desliming-rapid flotation-coarse grinding-flotation-zinc concentrate regrinding followed by desulfurization process. This method rapidly selects some coarse, easily floatable zinc oxide particles as high-quality zinc oxide concentrate. For zinc oxide that is not fully liberated, it is subjected to flotation after grinding. The high-quality zinc oxide concentrate produced by rapid flotation is combined with the low-quality zinc oxide concentrate obtained after desulfurization to form a qualified zinc concentrate.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore includes the following steps:

[0008] Step 1: Physical desliming

[0009] Take 940-1160g of lead-zinc oxide ore flotation tailings slurry with a mass concentration of 34.5-42.5%, first strongly disperse and stir, then weakly stir, and then weakly stir while simultaneously desliming by siphon. During the strong dispersion and desliming process, add modified water glass at a dosage of 300-500g / t. Collect the deslimed slurry. The desliming yield of the lead-zinc oxide ore flotation tailings slurry is 7.75-11.61%, and the zinc loss rate is 6.52-10.28%.

[0010] Step 2: Rapid Flotation

[0011] The slurry collected in step one is concentrated. Under the conditions of a slurry fineness of -200 mesh, a slurry mass percentage content of 52.41-55.89%, and a mass concentration of 26-29%, GH-7 modifier is added to the slurry at a ratio of 2500-3500 g / t, sodium sulfide activator at a ratio of 10000-15000 g / t, and GY-101 collector at a ratio of 300-400 g / t. Rapid flotation is then performed to obtain zinc concentrate 1 and rapid flotation tailings. The zinc concentrate 1 has a zinc mass percentage content of 28-29%, and a zinc recovery rate of 25-28%.

[0012] Step 3: Rapid flotation tailings coarse grinding

[0013] The rapid flotation tailings obtained in step two are then ground to a grinding concentration of 25-28%. GH-7 modifier is added to the ball mill at a ratio of 500-1000 g / t, resulting in a grinding fineness of -200 mesh and a pulp mass percentage of 55.31-60%.

[0014] Step 4: Flotation

[0015] The slurry ground in step three is subjected to flotation. The roughing concentration is 24-27%. Sodium sulfide activator is added at a ratio of 10,000-20,000 g / t, and collector GY-101 is added at a ratio of 100-200 g / t. The process involves one roughing, two cleaning, and one scavenging to produce zinc concentrate 2 and flotation tailings 1. The zinc concentrate 2 contains 17.86-20% zinc by mass, and the zinc recovery rate is 50.12-55%.

[0016] Step 5: Re-grinding of zinc concentrate 2

[0017] The zinc concentrate 2 obtained in step four is placed in a ball mill and ground at a grinding concentration of 30-32% to obtain zinc concentrate 2 powder with a fineness of -200 mesh and a zinc mass percentage content of 68-70%.

[0018] Step 6: Zinc concentrate reverse flotation desulfurization

[0019] The zinc concentrate 2 powder processed in step 5 is subjected to reverse flotation desulfurization under the condition of flotation concentration of 32.05-35%, with copper sulfate added at a ratio of 30-50 g / t and butyl xanthate added at a ratio of 50-100 g / t, to obtain low-quality zinc concentrate 3 and desulfurization froth. The zinc concentrate 3 has a zinc mass percentage content of 23-25%.

[0020] The zinc concentrate 1 collected in step one and the zinc concentrate 3 prepared in step six are used as the final zinc concentrate, and the flotation tailings 1 prepared in step four and the desulfurization foam prepared in step six are used as the final tailings; the zinc mass percentage content in the final zinc concentrate is 25.21-27%, and the zinc recovery rate is 72-75%.

[0021] Preferably, in step one, during strong dispersion and stirring, the mixer power is 20-25W, the rotation speed is 800-1000 rpm, and the stirring time is 3.5-4.5 minutes. Both coarse and fine particles in the slurry move at high speed. The fine particles of mineral mud adsorbed on the surface of zinc oxide are detached from the mineral surface due to shear force and are uniformly dispersed in the slurry under the action of modified water glass. During weak stirring, the mixer power is 2.0-2.5W, the rotation speed is 80-100 rpm, and the stirring time is 15-17 minutes. After the stirring speed and power are reduced, the coarse particles in the slurry settle to the bottom of the beaker because gravity is greater than the shear force they receive. The fine particles continue to disperse in the middle and upper part of the slurry under the shear force of stirring, thus separating the coarse and fine particles.

[0022] Preferably, the modifier GH-7 comprises the following components in parts by weight: 3-5 parts sodium silicate, 1-2 parts hydroxyethyl cellulose, 0.5-1 parts synthetic tannin, and 1.5-2 parts sodium bicarbonate.

[0023] Preferably, the collector GY-101 comprises the following components in parts by weight: 1-2 parts of cocoyl amine, 3-6 parts of N-hydroxyphthalimide, 0.5-1 part of No. 25 black powder, 0.5-1 part of kerosene, and 2-4 parts of acetic acid.

[0024] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0025] This invention employs a method of strong dispersion stirring followed by weak stirring and then weak stirring siphon desliming to effectively remove fine mud from zinc oxide while reducing the zinc loss rate in the mud. The desliming method is simple, low-cost, and easy to industrialize.

[0026] This invention employs a rapid flotation-coarse grinding-flotation-zinc concentrate regrinding followed by desulfurization process. A portion of the coarse, easily floatable zinc oxide is rapidly selected as high-quality zinc oxide concentrate. For zinc oxide that is not fully liberated, flotation is performed after grinding. To prevent the formation of secondary slime after over-grinding, coarse grinding followed by flotation is necessary. Due to the influence of sulfur, the grade of the zinc concentrate obtained from flotation is low, making it difficult to become a qualified product. To further improve the quality of the zinc concentrate, regrinding followed by desulfurization is required. Since most of the gangue minerals have been removed, there is no need to worry about the impact of secondary slime; grinding at this point allows for the fullest possible liberation of zinc and sulfur. After reverse flotation desulfurization, the quality of the zinc concentrate is greatly improved. The high-quality zinc oxide concentrate produced by rapid flotation is then combined with the low-quality zinc oxide concentrate obtained after desulfurization to form a qualified zinc concentrate.

[0027] The modifier GH-7 and collector GY-101 used in this invention play a key role in the flotation of zinc oxide. Modifier GH-7 can effectively reduce the amount of gangue added during the cleaning operation and ensure the quality of zinc concentrate. Collector GY-101 can reduce the viscosity of foam, improve the stability of reagent action, and has strong collecting ability, which can improve the efficiency of zinc cleaning operation and thus ensure the final recovery rate of zinc.

[0028] The process described in this invention is simple, low-cost, and highly applicable, with a zinc oxide recovery rate of 72-75%. It has good application prospects for the recovery of zinc oxide with high sulfur content. Attached Figure Description

[0029] Figure 1 This is the process flow diagram of this method. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings.

[0031] Example 1

[0032] A lead-zinc mine in Inner Mongolia has a raw ore grade of 2.37% lead, 8.45% zinc, and 1.89% sulfur. The lead oxidation rate is 54.17%, and the zinc oxidation rate is 59.42%. On-site production employs a method of preferential flotation of lead sulfide, followed by lead oxide, and then mixed flotation of zinc sulfide and pyrite to produce zinc oxide. This method is costly, and the zinc oxide is directly discharged into the tailings pond as tailings. The zinc content (by mass) in the on-site flotation tailings slurry sample is 4.46%.

[0033] A method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore includes the following steps:

[0034] Step 1: Physical desliming

[0035] Take 946g (940-1160g) of lead-zinc oxide ore flotation tailings slurry with a mass concentration of 40.67%-34.5-42.5%. First, vigorously disperse and stir, then weakly stir, and then simultaneously deslim by siphoning while weakly stirring. Modified water glass is added during the vigorous dispersion and desliming process, with a dosage of 350g / t. Collect the deslimed slurry. The desliming yield of the lead-zinc oxide ore flotation tailings slurry is 10.23%, and the zinc loss rate is 9.65%.

[0036] During strong dispersion stirring, the mixer power is 20W, the speed is 800 rpm, and the stirring time is 4 minutes. Both coarse and fine particles in the slurry move at high speed. The fine particles of mineral mud adsorbed on the surface of zinc oxide are detached from the mineral surface due to shear force and are uniformly dispersed in the slurry under the action of modified water glass. During weak stirring, the mixer power is 2.0W, the speed is 80 rpm, and the stirring time is 16 minutes. After the stirring speed and power are reduced, the coarse particles in the slurry settle to the bottom of the beaker because gravity is greater than the shear force. The fine particles continue to disperse in the middle and upper part of the slurry under the action of shear force during stirring, thus separating the coarse and fine particles.

[0037] Step 2: Rapid Flotation

[0038] The slurry collected in step one was concentrated. With a slurry fineness of -200 mesh, a slurry mass percentage content of 52.41%, and a mass concentration of 27.5%, GH-7 modifier was added to the slurry at a ratio of 3000 g / t, sodium sulfide activator at a ratio of 12000 g / t, and GY-101 collector at a ratio of 350 g / t. Rapid flotation was then performed to obtain zinc concentrate 1 and rapid flotation tailings. The zinc concentrate 1 contained 28.34% zinc by mass, and the zinc recovery rate was 26.75%.

[0039] Step 3: Rapid flotation tailings coarse grinding

[0040] The rapid flotation tailings obtained in step two were ground to a grinding concentration of 26.34%. GH-7 modifier was added to the ball mill at a ratio of 750 g / t, the grinding fineness was -200 mesh, and the slurry mass percentage content was 55.31%.

[0041] Step 4: Flotation

[0042] The slurry ground in step three was subjected to flotation. The roughing concentration was 26.35%. Sodium sulfide activator was added at a ratio of 15,000 g / t, and collector GY-101 was added at a ratio of 150 g / t. The process involved one roughing, two cleaning, and one scavenging to produce zinc concentrate 2 and flotation tailings 1. The zinc concentrate 2 contained 19.33% zinc by mass, and the zinc recovery rate was 53.74%.

[0043] Step 5: Re-grinding of zinc concentrate 2

[0044] The zinc concentrate 2 obtained in step four was placed in a ball mill and ground at a grinding concentration of 30% to obtain zinc concentrate 2 powder with a fineness of -200 mesh and a zinc mass percentage content of 69.14%.

[0045] Step 6: Zinc concentrate reverse flotation desulfurization

[0046] The zinc concentrate 2 powder processed in step 5 was subjected to reverse flotation desulfurization under the condition of flotation concentration of 32.05%, with copper sulfate added at a ratio of 35 g / t and butyl xanthate added at a ratio of 80 g / t, to obtain low-quality zinc concentrate 3 and desulfurization froth. The zinc content of zinc concentrate 3 was 24.51% by mass.

[0047] The zinc concentrate 1 collected in step one and the zinc concentrate 3 prepared in step six are used as the final zinc concentrate, and the flotation tailings 1 prepared in step four and the desulfurization foam prepared in step six are used as the final tailings; the zinc content in the final zinc concentrate is 26.37% by mass, and the zinc recovery rate is 73.98%.

[0048] In this embodiment, modifier GH-7 comprises the following components in parts by weight: 3.5 parts sodium silicate, 1 part hydroxyethyl cellulose, 0.6 parts synthetic tannin, and 1.5 parts sodium bicarbonate. Collector GY-101 comprises the following components in parts by weight: 1.5 parts cocoyl amine, 3 parts N-hydroxyphthalimide, 1 part No. 25 black powder, 1 part kerosene, and 2 parts acetic acid.

[0049] Example 2

[0050] A lead-zinc mine in Yunnan Province is a typical oxidized lead-zinc deposit in China. The raw ore contains 1.22% lead, 5.33% zinc, and 1.48% sulfur by mass. The oxidation rate of lead is 63.78%, and that of zinc is 60.23%. The beneficiation plant uses a process that prioritizes lead sulfide, then lead oxide, and finally zinc oxide. The zinc content in the flotation tailings is 3.43%, which has not been recovered, resulting in a waste of mineral resources. An on-site flotation tailings slurry was used to conduct zinc oxide recovery tests.

[0051] A method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore includes the following steps:

[0052] Step 1: Physical desliming

[0053] Take 940g of lead-zinc oxide ore flotation tailings slurry with a mass concentration of 34.5%. First, vigorously disperse and stir, then weakly stir, and then simultaneously siphon deslim while weakly stirring. Modified water glass is added during the vigorous dispersion and desliming process, with a dosage of 300g / t. Collect the deslimed slurry. The desliming yield of the lead-zinc oxide ore flotation tailings slurry is 7.75%, and the zinc loss rate is 6.52%.

[0054] During strong dispersion stirring, the mixer power is 22W, the speed is 880 rpm, and the stirring time is 3.5 minutes. Both coarse and fine particles in the slurry move at high speed. The fine particles of mineral mud adsorbed on the surface of zinc oxide are detached from the mineral surface due to shear force and are uniformly dispersed in the slurry under the action of modified water glass. During weak stirring, the mixer power is 2.3W, the speed is 92 rpm, and the stirring time is 15 minutes. After the stirring speed and power are reduced, the coarse particles in the slurry settle to the bottom of the beaker because gravity is greater than the shear force. The fine particles continue to disperse in the middle and upper part of the slurry under the action of shear force during stirring, thus separating the coarse and fine particles.

[0055] Step 2: Rapid Flotation

[0056] The slurry collected in step one was concentrated. Under the conditions of a slurry fineness of -200 mesh, a slurry mass percentage content of 55.89%, and a mass concentration of 26%, GH-7 modifier was added to the slurry at a ratio of 2500 g / t, sodium sulfide activator at a ratio of 15000 g / t, and GY-101 collector at a ratio of 400 g / t. Rapid flotation was then performed to obtain zinc concentrate 1 and rapid flotation tailings. The zinc concentrate 1 contained 29% zinc by mass, and the zinc recovery rate was 28%.

[0057] Step 3: Rapid flotation tailings coarse grinding

[0058] The rapid flotation tailings obtained in step two are then ground to a grinding concentration of 25%. GH-7 modifier is added to the ball mill at a ratio of 1000 g / t, resulting in a grinding fineness of -200 mesh and a pulp mass percentage of 58.97%.

[0059] Step 4: Flotation

[0060] The slurry ground in step three was subjected to flotation. The roughing concentration was 24%. Sodium sulfide activator was added at a ratio of 10,000 g / t, and collector GY-101 was added at a ratio of 200 g / t. The process involved one roughing, two cleaning, and one scavenging to produce zinc concentrate 2 and flotation tailings 1. The zinc concentrate 2 contained 18.22% zinc by mass, and the zinc recovery rate was 50.12%.

[0061] Step 5: Re-grinding of zinc concentrate 2

[0062] The zinc concentrate 2 obtained in step four was placed in a ball mill and ground at a grinding concentration of 32% to obtain zinc concentrate 2 powder with a fineness of -200 mesh and a zinc mass percentage content of 68%.

[0063] Step 6: Zinc concentrate reverse flotation desulfurization

[0064] The zinc concentrate 2 powder processed in step 5 was subjected to reverse flotation desulfurization at a flotation concentration of 35%, with copper sulfate added at a ratio of 30 g / t and butyl xanthate added at a ratio of 100 g / t, to obtain low-quality zinc concentrate 3 and desulfurization froth. The zinc concentrate 3 contained 23% zinc by mass.

[0065] The zinc concentrate 1 collected in step one and the zinc concentrate 3 prepared in step six are used as the final zinc concentrate, and the flotation tailings 1 prepared in step four and the desulfurization foam prepared in step six are used as the final tailings; the zinc content in the final zinc concentrate is 25.21% by mass, and the zinc recovery rate is 72%.

[0066] In this embodiment, the modifier GH-7 comprises the following components in parts by weight: 3 parts sodium silicate, 1.5 parts hydroxyethyl cellulose, 0.5 parts synthetic tannin, and 1.8 parts sodium bicarbonate. The collector GY-101 comprises the following components in parts by weight: 2 parts cocoyl amine, 3 parts N-hydroxyphthalimide, 0.5 parts No. 25 black powder, 0.5 parts kerosene, and 3 parts acetic acid.

[0067] Example 3

[0068] A lead-zinc mine in Hunan Province had the following elemental percentages in its raw ore: lead 1.55%, zinc 6.45%, sulfur 1.23%, lead oxidation rate of 55.23%, and zinc oxidation rate of 57.02%. The concentrator uses a process that prioritizes lead sulfide, then lead oxide, and finally zinc oxide. The zinc content in the flotation tailings was 2.21%, which had not been recovered, resulting in a waste of mineral resources. An on-site flotation tailings slurry was used to conduct zinc oxide recovery experiments.

[0069] A method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore includes the following steps:

[0070] Step 1: Physical desliming

[0071] 1030g of lead-zinc oxide ore flotation tailings slurry with a mass concentration of 42.5% was taken, first strongly dispersed and stirred, then weakly stirred, and then weakly stirred while simultaneously desliming by siphon. Modified water glass was added during the strong dispersion and desliming process, with a dosage of 500g / t. The deslimed slurry was collected, and the desliming yield of the lead-zinc oxide ore flotation tailings slurry was 11.61%, with a zinc loss rate of 10.28%.

[0072] During strong dispersion stirring, the mixer power is 25W, the speed is 1000 rpm, and the stirring time is 4.5 minutes. Both coarse and fine particles in the slurry move at high speed. The fine mineral mud adsorbed on the surface of zinc oxide is detached from the mineral surface due to shear force and is uniformly dispersed in the slurry under the action of modified water glass. During weak stirring, the mixer power is 2.5W, the speed is 100 rpm, and the stirring time is 17 minutes. After the stirring speed and power are reduced, the coarse particles in the slurry settle to the bottom of the beaker because gravity is greater than the shear force. The fine particles continue to disperse in the middle and upper part of the slurry under the action of shear force during stirring, thus separating the coarse and fine particles.

[0073] Step 2: Rapid Flotation

[0074] The slurry collected in step one was concentrated. Under the conditions of a slurry fineness of -200 mesh, a slurry mass percentage content of 54.23%, and a mass concentration of 29%, GH-7 modifier was added to the slurry at a ratio of 3500 g / t, sodium sulfide activator at a ratio of 10000 g / t, and GY-101 collector at a ratio of 300 g / t. Rapid flotation was then performed to obtain zinc concentrate 1 and rapid flotation tailings. The zinc concentrate 1 contained 28% zinc by mass, and the zinc recovery rate was 25%.

[0075] Step 3: Rapid flotation tailings coarse grinding

[0076] The rapid flotation tailings obtained in step two were ground to a grinding concentration of 27.41%. GH-7 modifier was added to the ball mill at a ratio of 500 g / t, the grinding fineness was -200 mesh, and the slurry mass percentage content was 60%.

[0077] Step 4: Flotation

[0078] The slurry ground in step three is subjected to flotation. The roughing concentration is 27%. Sodium sulfide activator is added at a ratio of 20,000 g / t and collector GY-101 is added at a ratio of 100 g / t. The process involves one roughing, two cleaning, and one scavenging to produce zinc concentrate 2 and flotation tailings 1. The zinc concentrate 2 contains 20% zinc by mass and the zinc recovery rate is 55%.

[0079] Step 5: Re-grinding of zinc concentrate 2

[0080] The zinc concentrate 2 obtained in step four was placed in a ball mill and ground at a grinding concentration of 31.55% to obtain zinc concentrate 2 powder with a fineness of -200 mesh and a zinc mass percentage content of 70%.

[0081] Step 6: Zinc concentrate reverse flotation desulfurization

[0082] The zinc concentrate 2 powder processed in step 5 was subjected to reverse flotation desulfurization at a flotation concentration of 33.77%, with copper sulfate added at a ratio of 50 g / t and butyl xanthate added at a ratio of 50 g / t, to obtain low-quality zinc concentrate 3 and desulfurization froth. The zinc content of zinc concentrate 3 was 25% by mass.

[0083] The zinc concentrate 1 collected in step one and the zinc concentrate 3 prepared in step six are used as the final zinc concentrate, and the flotation tailings 1 prepared in step four and the desulfurization foam prepared in step six are used as the final tailings; the zinc content in the final zinc concentrate is 27% by mass and the zinc recovery rate is 74.31%.

[0084] In this embodiment, the modifier GH-7 comprises the following components in parts by weight: 5 parts sodium silicate, 2 parts hydroxyethyl cellulose, 1 part synthetic tannin, and 2 parts sodium bicarbonate. The collector GY-101 comprises the following components in parts by weight: 1 part cocoyl amine, 6 parts N-hydroxyphthalimide, 1 part No. 25 black powder, 1 part kerosene, and 4 parts acetic acid.

[0085] Example 4

[0086] A lead-zinc mine in Gansu Province is a typical domestic oxide lead-zinc deposit. The mass percentage content of each element in the raw ore is as follows: lead 1.51%, zinc 7.63%, sulfur 1.79%. The process adopts the priority flotation of lead sulfide, then lead oxide, and finally zinc oxide and pyrite. The flotation tailings slurry was taken from the production site. The mass percentage content of zinc in the flotation tailings was 4.11%. Zinc oxide recovery test was carried out.

[0087] A method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore includes the following steps:

[0088] Step 1: Physical desliming

[0089] 1160g of lead-zinc oxide ore flotation tailings slurry with a mass concentration of 38.94% was taken, and first strongly dispersed and stirred, then weakly stirred, and then weakly stirred while siphoning desliming. Modified water glass was added during the strong dispersion and desliming process, with a dosage of 475g / t. The deslimed slurry was collected, and the desliming yield of the lead-zinc oxide ore flotation tailings slurry was 8.95%, and the zinc loss rate was 9.34%.

[0090] During vigorous dispersion stirring, the mixer power is 24W, the speed is 960 rpm, and the stirring time is 3.5 minutes. Both coarse and fine particles in the slurry move at high speed. The fine mineral mud adsorbed on the surface of zinc oxide is detached from the mineral surface due to shear force and is uniformly dispersed in the slurry under the action of modified water glass. During weak stirring, the mixer power is 2.4W, the speed is 96 rpm, and the stirring time is 16.5 minutes. After the stirring speed and power are reduced, the coarse particles in the slurry settle to the bottom of the beaker because gravity is greater than the shear force. The fine particles continue to disperse in the middle and upper part of the slurry under the shear force of stirring, thus separating the coarse and fine particles.

[0091] Step 2: Rapid Flotation

[0092] The slurry collected in step one was concentrated. With a slurry fineness of -200 mesh, a slurry mass percentage content of 53.45%, and a mass concentration of 28.37%, GH-7 modifier was added to the slurry at a ratio of 2800 g / t, sodium sulfide activator at a ratio of 13500 g / t, and GY-101 collector at a ratio of 375 g / t. Rapid flotation was then performed to obtain zinc concentrate 1 and rapid flotation tailings. The zinc concentrate 1 contained 28.76% zinc by mass, and the zinc recovery rate was 27.31%.

[0093] Step 3: Rapid flotation tailings coarse grinding

[0094] The rapid flotation tailings obtained in step two are ground to a grinding concentration of 28%. GH-7 modifier is added to the ball mill at a ratio of 820 g / t, the grinding fineness is -200 mesh, and the slurry mass percentage content is 57.38%.

[0095] Step 4: Flotation

[0096] The slurry ground in step three was subjected to flotation. The roughing concentration was 25.67%. Sodium sulfide activator was added at a ratio of 18,000 g / t, and collector GY-101 was added at a ratio of 120 g / t. The process involved one roughing, two cleaning, and one scavenging to produce zinc concentrate 2 and flotation tailings 1. The zinc concentrate 2 contained 17.86% zinc by mass, and the zinc recovery rate was 53.67%.

[0097] Step 5: Re-grinding of zinc concentrate 2

[0098] The zinc concentrate 2 obtained in step four was placed in a ball mill and ground at a grinding concentration of 30.87% to obtain zinc concentrate 2 powder with a fineness of -200 mesh and a zinc mass percentage content of 68.89%.

[0099] Step 6: Zinc concentrate reverse flotation desulfurization

[0100] The zinc concentrate 2 powder processed in step 5 was subjected to reverse flotation desulfurization at a flotation concentration of 34.78%, with copper sulfate added at a ratio of 45 g / t and butyl xanthate added at a ratio of 60 g / t, to obtain low-quality zinc concentrate 3 and desulfurization froth. The zinc concentrate 3 contained 23.84% zinc by mass.

[0101] The zinc concentrate 1 collected in step one and the zinc concentrate 3 prepared in step six are used as the final zinc concentrate, and the flotation tailings 1 prepared in step four and the desulfurization foam prepared in step six are used as the final tailings; the zinc content in the final zinc concentrate is 26.88% by mass and the zinc recovery rate is 75%.

[0102] In this embodiment, the modifier GH-7 comprises the following components in parts by weight: 4 parts sodium silicate, 1.5 parts hydroxyethyl cellulose, 0.8 parts synthetic monohydrate, and 1.6 parts sodium bicarbonate. The collector GY-101 comprises the following components in parts by weight: 1.5 parts cocoyl amine, 4 parts N-hydroxyphthalimide, 0.5 parts No. 25 black powder, 0.5 parts kerosene, and 3 parts acetic acid.

[0103] The above are merely preferred embodiments of the present invention. It should be noted that, for those skilled in the art, other equivalent modifications and improvements can be made based on the technical teachings provided by the present invention, and these should also be considered within the scope of protection of the present invention.

Claims

1. A method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore, characterized in that: Includes the following steps: Step 1: Physical desliming Take 940-1160g of lead-zinc oxide ore flotation tailings slurry with a mass concentration of 34.5-42.5%, first strongly disperse and stir, then weakly stir, and then weakly stir while simultaneously desliming by siphon. During the strong dispersion and desliming process, add modified water glass at a dosage of 300-500g / t. Collect the deslimed slurry. The desliming yield of the lead-zinc oxide ore flotation tailings slurry is 7.75-11.61%, and the zinc loss rate is 6.52-10.28%. Step 2: Rapid Flotation The slurry collected in step one is concentrated. Under the conditions of a slurry fineness of -200 mesh, a slurry mass percentage content of 52.41-55.89%, and a mass concentration of 26-29%, GH-7 modifier is added to the slurry at a ratio of 2500-3500 g / t, sodium sulfide activator at a ratio of 10000-15000 g / t, and collector GY-101 at a ratio of 300-400 g / t. Rapid flotation is then performed to obtain zinc concentrate 1 and rapid flotation tailings. The zinc concentrate 1 has a zinc mass percentage content of 28-29% and a zinc recovery rate of 25-28%. Step 3: Rapid flotation tailings coarse grinding The rapid flotation tailings obtained in step two are then ground to a grinding concentration of 25-28%. GH-7 modifier is added to the ball mill at a ratio of 500-1000 g / t, resulting in a grinding fineness of -200 mesh and a pulp mass percentage of 55.31-60%. Step 4: Flotation The slurry ground in step three is subjected to flotation. The roughing concentration is 24-27%. Sodium sulfide activator is added at a ratio of 10,000-20,000 g / t, and collector GY-101 is added at a ratio of 100-200 g / t. The process involves one roughing, two cleaning, and one scavenging to produce zinc concentrate 2 and flotation tailings 1. The zinc concentrate 2 contains 17.86-20% zinc by mass, and the zinc recovery rate is 50.12-55%. Step 5: Re-grinding of zinc concentrate 2 The zinc concentrate 2 obtained in step four is placed in a ball mill and ground at a grinding concentration of 30-32% to obtain zinc concentrate 2 powder with a fineness of -200 mesh and a zinc mass percentage content of 68-70%. Step 6: Zinc concentrate reverse flotation desulfurization The zinc concentrate 2 powder processed in step 5 is subjected to reverse flotation desulfurization under the condition of flotation concentration of 32.05-35%, with copper sulfate added at a ratio of 30-50 g / t and butyl xanthate added at a ratio of 50-100 g / t, to obtain low-quality zinc concentrate 3 and desulfurization froth. The zinc concentrate 3 has a zinc mass percentage content of 23-25%. The zinc concentrate 1 collected in step one and the zinc concentrate 3 prepared in step six are used as the final zinc concentrate, and the flotation tailings 1 prepared in step four and the desulfurization foam prepared in step six are used as the final tailings; the zinc content in the final zinc concentrate is 25.21-27% by mass, and the zinc recovery rate is 72-75%; The modifier GH-7 comprises the following components in parts by weight: 3-5 parts sodium silicate, 1-2 parts hydroxyethyl cellulose, 0.5-1 parts synthetic tannin, and 1.5-2 parts sodium bicarbonate. The collector GY-101 comprises the following components in parts by weight: 1-2 parts of coconut oil amine, 3-6 parts of N-hydroxyphthalimide, 0.5-1 part of No. 25 black powder, 0.5-1 part of kerosene, and 2-4 parts of acetic acid.

2. The method for recovering zinc oxide from flotation tailings of lead-zinc oxide ore according to claim 1, characterized in that: In step one, during strong dispersion and stirring, the mixer power is 20-25W, the rotation speed is 800-1000 rpm, and the stirring time is 3.5-4.5 minutes. Both coarse and fine particles in the slurry move at high speed. The fine mineral mud adsorbed on the zinc oxide surface is detached from the mineral surface due to shear force and is uniformly dispersed in the slurry under the action of modified water glass. During weak stirring, the mixer power is 2.0-2.5W, the rotation speed is 80-100 rpm, and the stirring time is 15-17 minutes. After the stirring speed and power are reduced, the coarse particles in the slurry settle to the bottom of the beaker because gravity is greater than the shear force they receive. The fine particles continue to disperse in the middle and upper part of the slurry under the shear force of stirring, thus separating the coarse and fine particles.

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