Cascade flotation desiliconization and decalcification method for silicon-calcium copper oxide ore

Abstract

The invention relates to a step flotation desiliconization and decalcification method for silicon-calcium copper oxide ore, and belongs to the technical field of mineral processing. Aiming at the problems that the silicon-calcium copper oxide ore is low in copper grade, multiple in gangue variety and high in silicon-calcium mineral content, and an existing inhibitor is large in dosage, poor in selectivity, poor in inhibition effect and the like, the method comprises the steps that a targeted inhibitor A is used for preferentially and selectively inhibiting siliceous gangue in ore, and a copper ore pre-enriched product containing the calcium gangue is obtained; and then a targeted inhibitor B is added to deeply and accurately inhibit calcium gangue in the pre-enriched product, and high-grade copper concentrate is obtained. According to the method, most siliceous gangue and part of calcareous gangue in the ore can be removed through desilicication operation, and the ore handling capacity of the follow-up process is greatly reduced; and enrichment is conducted again through decalcification operation, and accurate separation of copper minerals and calcium gangue can be achieved. Based on step-by-step targeted inhibition of different types of gangue, the impurity content of the copper concentrate can be remarkably reduced, and the technical problem that synchronous and efficient inhibition of the silicon-calcium gangue is difficult is solved.

Description

Technical Field

[0001] This invention relates to a step-flotation desiliconization and decalcification method for siliceous-calcium oxide copper ore, belonging to the field of mineral processing technology. Background Technology

[0002] Silicate-calcareous copper oxide ore is an important copper resource. The copper minerals in the ore are mainly malachite and azurite, while the gangue minerals are primarily composed of silicates (such as quartz and feldspar) and carbonates (such as calcite and dolomite). Industrially, flotation is commonly used for pre-enrichment of this type of ore to remove most of the gangue minerals, providing high-quality raw materials for subsequent smelting processes. In the subsequent leaching process, gangue minerals have a significant negative impact: large amounts of silicate minerals react with acid to form silica gel, not only wasting acid reagents but also forming difficult-to-filter colloidal substances, causing equipment blockage and significantly reducing solid-liquid separation efficiency. Besides silicates, carbonate minerals such as calcite and dolomite react even more violently with acid. The carbon dioxide released during the reaction produces a large amount of foam, disrupting the stability of the leaching system. Simultaneously, excess dissolved calcium ions may react with other components in the leachate to form precipitates, further interfering with subsequent processes. Therefore, efficient removal of silicate and carbonate gangue from siliceous-calcareous copper oxide ores is crucial for optimizing subsequent metallurgical processes, reducing production costs, and ensuring copper recovery rates.

[0003] Currently, water glass and sodium hexametaphosphate are still the main industrial inhibitors for siliceous gangue. However, these inhibitors have poor selectivity and weak targeted inhibition ability against silicate and carbonate gangues, requiring increased dosage to ensure their inhibitory effect. However, excessive addition can lead to highly dispersed tailings, severely affecting subsequent sedimentation and solid-liquid separation efficiency and increasing wastewater treatment costs. Furthermore, residual reagents can easily adsorb onto the surfaces of target minerals such as malachite and azurite, weakening the selective adsorption effect of subsequent collectors. To compensate for the shortcomings of single inhibitors, multiple inhibitors are often used in combination in industry to achieve simultaneous inhibition of all gangues in the ore. However, the crystal structures and surface physicochemical properties of silicate and carbonate minerals in the ore are fundamentally different, and their mechanisms of action also differ significantly from those of the inhibitors, making simultaneous and effective inhibition difficult. In addition, the inhibitors of siliceous and calcium-rich gangue tend to compete for adsorption or chemical reaction with xanthates and hydroxamic acid collectors commonly used in copper oxide ores, which can disrupt the selectivity of the collecting system, resulting in poor flotation separation and ultimately low grade copper oxide concentrate with insufficient copper recovery.

[0004] Therefore, there is an urgent need to develop new and efficient targeted inhibitors, as well as compatible collectors and beneficiation processes, to deeply remove silicate and carbonate gangue minerals from siliceous-calcareous copper oxide ores, while avoiding the inhibition of target copper oxide minerals such as malachite and azurite, thereby achieving efficient separation and comprehensive recovery of complex and difficult-to-benefit siliceous-calcareous copper oxide ores. Summary of the Invention

[0005] To address the problems of low copper grade, diverse gangue types, and high silica-calcium mineral content in siliceous-calcium copper oxide ores, and the limitations of existing inhibitors such as large dosage, poor selectivity, and ineffective suppression, this invention proposes a cascade flotation desilication and decalcification method for siliceous-calcium copper oxide ores. The desilication process selectively suppresses siliceous gangue, thereby removing most of the siliceous gangue and some calcic gangue from the ore, significantly reducing the ore throughput in subsequent processes. Then, a decalcification process is used for re-enrichment, achieving precise separation of copper minerals and calcic gangue, effectively solving the technical challenge of simultaneously and efficiently suppressing silica-calcium gangue.

[0006] A step-flotation desilication and decalcification method for siliceous-calcium copper oxide ore, the specific steps of which are as follows: (1) Stir and adjust the slurry of siliceous calcium oxide copper ore to a slurry mass percentage concentration of 23-37%, then add targeted inhibitor A and targeted collector A in sequence to carry out one desilication operation, and obtain one desilication concentrate and one desilication tailings; (2) Targeted inhibitor A and targeted collector A are added sequentially to the primary desilication tailings obtained in step (1) to carry out secondary desilication operation, thereby obtaining secondary desilication concentrate and secondary desilication tailings; the secondary desilication tailings are flotation tailings I; (3) After the primary desilication concentrate obtained in step (1) and the secondary desilication concentrate obtained in step (2) are combined, sodium sulfide, targeted inhibitor B and targeted collector B are added in sequence to carry out a decalcification operation to obtain a primary decalcification concentrate and a primary decalcification tailings. (4) Targeted inhibitor B and targeted collector B are added sequentially to the primary decalcification tailings obtained in step (3) to carry out secondary decalcification, thereby obtaining secondary decalcification concentrate and secondary decalcification tailings; the secondary decalcification tailings are flotation tailings II; (5) After the primary decalcification concentrate obtained in step (3) and the secondary decalcification concentrate obtained in step (4) are combined, targeted inhibitor B and targeted collector B are added in sequence to perform a primary cleaning operation to obtain a primary cleaning concentrate and a primary cleaning tailings. The primary cleaning tailings are returned to the slurry and incorporated into the secondary decalcification operation. (6) After the primary concentrate obtained in step (5) is slurried, a secondary cleaning operation is carried out to obtain secondary concentrate and secondary tailings. The secondary tailings are returned to the slurry and incorporated into the primary cleaning operation. (7) The secondary concentrate obtained in step (6) is flotation copper concentrate. The flotation tailings I obtained in step (2) and the flotation tailings II obtained in step (4) are combined to obtain flotation tailings. The targeted inhibitor A is composed of water glass, 2-hydroxyethyl ether cellulose and naphthalene sulfonate formaldehyde condensate; the targeted inhibitor B is composed of tetrasodium diphosphate, fenugreek gum and tetrasodium hydroxyethylidene diphosphonate; the targeted collector A is composed of sodium oleate, oxidized paraffin soap and benzohydroxyoxime acid; the targeted collector B is composed of isopentyl xanthate, ethyl thiocyanate and aniline black; and the foaming agent is pine oil.

[0007] Preferably, the mass percentage of copper in the siliceous calcium oxide copper ore in step (1) is 0.52~0.86%.

[0008] Preferably, based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added to the slurry in step (1) one desilication operation is 360~580g, and the amount of targeted collector A added is 320~500g.

[0009] Preferably, the amount of targeted inhibitor A added to the slurry in the secondary desilication operation of step (2) is 180~290g and the amount of targeted collector A added is 160~250g per ton of siliceous calcium oxide copper ore.

[0010] Preferably, based on each ton of siliceous calcium oxide copper ore, the amount of sodium sulfide added in the slurry of the first decalcification operation in step (3) is 600~1200g, the amount of targeted inhibitor B added is 240~400g, the amount of targeted collector B added is 200~360g, and the amount of foaming agent added is 20~30g.

[0011] Preferably, per ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added to the slurry in step (4) secondary decalcification operation is 120~200g, the amount of targeted collector B added is 100~180g, and the amount of foaming agent added is 10~15g.

[0012] Preferably, based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added to the slurry in step (5) one-time beneficiation operation is 60~100g, and the amount of targeted collector B added is 25~45g.

[0013] Preferably, based on the mass fraction of the targeted inhibitor A as 100%, the targeted inhibitor A contains 40-60% water glass, 35-45% 2-hydroxyethyl ether cellulose, and 5-15% naphthalene sulfonate formaldehyde condensate; Based on the mass fraction of the targeted inhibitor B as 100%, the targeted inhibitor B contains 35-55% tetrasodium diphosphate, 30-40% fenugreek gum, and 15-25% tetrasodium hydroxyethylidene diphosphonate.

[0014] Preferably, based on a mass fraction of 100% for the targeted collector A, the targeted collector A contains 30-50% sodium oleate, 30-40% oxidized paraffin soap, and 20-30% benzoyl hydroxyxamic acid; Based on a mass fraction of 100% for the targeted collector B, the targeted collector B contains 45-65% isopentyl xanthate, 20-30% ethyl thiocyanate, and 15-25% aniline black.

[0015] The beneficial effects of this invention are: (1) In view of the complex mineralogical characteristics of siliceous and calcareous copper oxide ore, this invention proposes a new strategy for the stepwise inhibition of siliceous and calcareous gangue minerals. By developing a targeted inhibitor that is precisely compatible with the collector system, the siliceous gangue minerals such as quartz and feldspar and the calcareous gangue minerals such as calcite and dolomite in the ore are precisely inhibited in stages, which significantly reduces the content of silicon and calcium impurities in the concentrate, and simultaneously improves the grade and recovery rate of copper concentrate. This achieves efficient and selective enrichment of copper oxide minerals, effectively solving the technical problems of the difficulty in simultaneously and efficiently inhibiting siliceous and calcareous gangue minerals and the poor compatibility between the inhibitor and the collector system. (2) The targeted inhibitor A of the present invention constructs a multi-inhibition system of "hydrophilic layer construction - hydrophilicity enhancement - adsorption barrier" through the synergistic effect of water glass, 2-hydroxyethyl ether cellulose and naphthalene sulfonate formaldehyde condensate. The silicate ions and colloidal silica generated by the hydrolysis of water glass are rapidly adsorbed on the surface of siliceous gangue to form an initial hydrophilic layer. 2-hydroxyethyl ether cellulose drives the hydrophilic groups to spread densely on the surface of gangue through the dual effects of hydrogen bonding and electrostatic adsorption, further enhancing its hydrophilicity. The sulfonate groups in the naphthalene sulfonate formaldehyde condensate are firmly anchored to the surface of gangue through electrostatic adsorption and hydrogen bonding. The naphthalene ring in the molecular chain simultaneously forms steric hindrance, effectively blocking the adsorption of the collector to the surface of gangue, thereby achieving targeted and efficient inhibition of siliceous gangue. (3) The tetrasodium diphosphate and tetrasodium hydroxyethylidene diphosphonate in the targeted inhibitor B of the present invention have a strong chelating effect on calcium ions on the surface of calcareous gangue, which can quickly form a stable drug anchoring layer; the hydrophilic groups such as hydroxyl and carboxyl groups on the fenugreek molecular chain are tightly adsorbed on the surface of calcareous gangue through hydrogen bonding with the anchoring layer, which not only enhances the adsorption stability of the inhibitor components, but also fills the microscopic gaps of the chelated anchoring layer, forming a denser and more uniform composite inhibition film, thereby achieving efficient and enhanced inhibition of calcareous gangue, which is conducive to the efficient separation of copper oxide minerals and calcareous gangue, and provides a new path for the efficient development and utilization of complex and difficult-to-process copper oxide mineral resources. Attached Figure Description

[0016] Figure 1 This is a process flow diagram of the present invention. Detailed Implementation

[0017] The present invention will be further described in detail below with reference to specific embodiments, but the scope of protection of the present invention is not limited to the content described.

[0018] In the following embodiments of the present invention, the targeted inhibitor A is composed of water glass, 2-hydroxyethyl ether cellulose and naphthalene sulfonate formaldehyde condensate, the targeted inhibitor B is composed of tetrasodium diphosphate, fenugreek gum and tetrasodium hydroxyethylidene diphosphonate, the targeted collector A is composed of sodium oleate, oxidized paraffin soap and benzohydroxyoxime acid, the targeted collector B is composed of isopentyl xanthate, ethyl thiocyanate and aniline black, and the foaming agent is pine oil.

[0019] Example 1: In this example, with the mass fraction of targeted inhibitor A being 100%, targeted inhibitor A contains 40% water glass, 45% 2-hydroxyethyl ether cellulose, and 15% naphthalene sulfonate formaldehyde condensate; with the mass fraction of targeted inhibitor B being 100%, targeted inhibitor B contains 35% tetrasodium diphosphate, 40% fenugreek gum, and 25% tetrasodium hydroxyethylidene diphosphonate; with the mass fraction of targeted collector A being 100%, targeted collector A contains 30% sodium oleate, 40% oxidized paraffin soap, and 30% benzohydroxyxamic acid; with the mass fraction of targeted collector B being 100%, targeted collector B contains 45% isopentyl xanthate, 30% ethyl thiocyanate, and 25% aniline black. In this embodiment, the copper content in the siliceous calcium oxide copper ore is 0.52% by mass. A stepwise flotation method for desiliconization and decalcification of siliceous-calcium oxide copper ore (see...) Figure 1 The specific steps are as follows: (1) The siliceous calcium oxide copper ore is stirred and slurryed to a slurry mass percentage concentration of 23%. Targeted inhibitor A and targeted collector A are added in sequence to carry out one desilication operation to obtain one desilication concentrate and one desilication tailings. The amount of targeted inhibitor A added to the slurry of one desilication operation is 360g and the amount of targeted collector A added is 320g per ton of siliceous calcium oxide copper ore. (2) In step (1), targeted inhibitor A and targeted collector A are added sequentially to the primary desilication tailings to carry out secondary desilication operation, thereby obtaining secondary desilication concentrate and secondary desilication tailings; the secondary desilication tailings are flotation tailings I; based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added in the slurry of the secondary desilication operation is 180g and the amount of targeted collector A added is 160g. (3) After the primary desilication concentrate obtained in step (1) and the secondary desilication concentrate obtained in step (2) are combined, sodium sulfide, targeted inhibitor B and targeted collector B are added in sequence to carry out a primary decalcification operation to obtain a primary decalcification concentrate and a primary decalcification tailings. Based on each ton of siliceous calcium oxide copper ore, the amount of sodium sulfide added in the slurry of the primary decalcification operation is 600g, the amount of targeted inhibitor B added is 240g, the amount of targeted collector B added is 200g, and the amount of frother added is 20g. (4) In step (3), targeted inhibitor B and targeted collector B are added sequentially to the primary decalcification tailings to carry out secondary decalcification, thereby obtaining secondary decalcification concentrate and secondary decalcification tailings; the secondary decalcification tailings are flotation tailings II; based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added in the slurry of the secondary decalcification operation is 120g, the amount of targeted collector B added is 100g, and the amount of frother added is 10g; (5) The primary decalcified concentrate obtained in step (3) and the secondary decalcified concentrate obtained in step (4) are combined and then targeted inhibitor B and targeted collector B are added in sequence to carry out a primary cleaning operation to obtain a primary cleaning concentrate and a primary cleaning tailings. The primary cleaning tailings are returned to the slurry and incorporated into the secondary decalcification operation. Based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added in the slurry of the primary cleaning operation is 60g and the amount of targeted collector B added is 25g. (6) After the primary concentrate obtained in step (5) is slurried, a secondary cleaning operation is carried out to obtain secondary concentrate and secondary tailings. The secondary tailings are returned to the slurry and incorporated into the primary cleaning operation. (7) The secondary concentrate obtained in step (6) is flotation copper concentrate. The flotation tailings I obtained in step (2) and the flotation tailings II obtained in step (4) are combined to obtain flotation tailings. In this embodiment, the copper flotation recovery rate was 83.5%.

[0020] Example 2: In this example, with the mass fraction of targeted inhibitor A being 100%, targeted inhibitor A contains 50% water glass, 40% 2-hydroxyethyl ether cellulose, and 10% naphthalene sulfonate formaldehyde condensate; with the mass fraction of targeted inhibitor B being 100%, targeted inhibitor B contains 45% tetrasodium diphosphate, 35% fenugreek gum, and 20% tetrasodium hydroxyethylidene diphosphonate; with the mass fraction of targeted collector A being 100%, targeted collector A contains 40% sodium oleate, 35% oxidized paraffin soap, and 25% benzohydroxyoxime acid; with the mass fraction of targeted collector B being 100%, targeted collector B contains 55% isopentyl xanthate, 25% ethyl thiocyanate, and 20% aniline black. In this embodiment, the copper content in the siliceous calcium oxide copper ore is 0.69% by mass. A stepwise flotation method for desiliconization and decalcification of siliceous-calcium oxide copper ore (see...) Figure 1The specific steps are as follows: (1) Stir and adjust the slurry of siliceous calcium oxide copper ore to a slurry mass percentage concentration of 30%, then add targeted inhibitor A and targeted collector A in sequence to carry out one desilication operation, and obtain one desilication concentrate and one desilication tailings; based on one ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added in the slurry of one desilication operation is 470g and the amount of targeted collector A added is 410g. (2) In step (1), targeted inhibitor A and targeted collector A are added sequentially to the primary desilication tailings to perform secondary desilication operation, thereby obtaining secondary desilication concentrate and secondary desilication tailings; the secondary desilication tailings are flotation tailings I; based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added to the slurry of the secondary desilication operation is 235g and the amount of targeted collector A added is 205g. (3) After the primary desilication concentrate obtained in step (1) and the secondary desilication concentrate obtained in step (2) are combined, sodium sulfide, targeted inhibitor B and targeted collector B are added in sequence to carry out a primary decalcification operation to obtain a primary decalcification concentrate and a primary decalcification tailings. Based on each ton of siliceous calcium oxide copper ore, the amount of sodium sulfide added in the slurry of the primary decalcification operation is 900g, the amount of targeted inhibitor B added is 320g, the amount of targeted collector B added is 280g, and the amount of frother added is 25g. (4) In step (3), targeted inhibitor B and targeted collector B are added sequentially to the primary decalcification tailings to carry out secondary decalcification, thereby obtaining secondary decalcification concentrate and secondary decalcification tailings; the secondary decalcification tailings are flotation tailings II; based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added in the slurry of the secondary decalcification operation is 160g, the amount of targeted collector B added is 140g, and the amount of frother added is 12g; (5) The primary decalcified concentrate obtained in step (3) and the secondary decalcified concentrate obtained in step (4) are combined and then targeted inhibitor B and targeted collector B are added sequentially to perform a primary cleaning operation to obtain a primary cleaning concentrate and a primary cleaning tailings. The primary cleaning tailings are returned to the slurry and incorporated into the secondary decalcification operation. Based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added in the slurry of the primary cleaning operation is 80g and the amount of targeted collector B added is 35g. (6) After the primary concentrate obtained in step (5) is slurried, a secondary cleaning operation is carried out to obtain secondary concentrate and secondary tailings. The secondary tailings are returned to the slurry and incorporated into the primary cleaning operation. (7) The secondary concentrate obtained in step (6) is flotation copper concentrate. The flotation tailings I obtained in step (2) and the flotation tailings II obtained in step (4) are combined to obtain flotation tailings. In this embodiment, the copper flotation recovery rate was 85.2%.

[0021] Example 3: In this example, with the mass fraction of targeted inhibitor A being 100%, targeted inhibitor A contains 60% water glass, 35% 2-hydroxyethyl ether cellulose, and 5% naphthalene sulfonate formaldehyde condensate; with the mass fraction of targeted inhibitor B being 100%, targeted inhibitor B contains 55% tetrasodium diphosphate, 30% fenugreek gum, and 15% tetrasodium hydroxyethylidene diphosphonate; with the mass fraction of targeted collector A being 100%, targeted collector A contains 50% sodium oleate, 30% oxidized paraffin soap, and 20% benzohydroxyoxime acid; with the mass fraction of targeted collector B being 100%, targeted collector B contains 65% isopentyl xanthate, 20% ethyl thiocyanate, and 15% aniline black. In this embodiment, the copper content in the siliceous calcium oxide copper ore is 0.86% by mass. A stepwise flotation method for desiliconization and decalcification of siliceous-calcium oxide copper ore (see...) Figure 1 The specific steps are as follows: (1) Stir and adjust the slurry of siliceous calcium oxide copper ore to a slurry mass percentage concentration of 37%, then add targeted inhibitor A and targeted collector A in sequence to carry out one desilication operation, and obtain one desilication concentrate and one desilication tailings; based on one ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added in the slurry of one desilication operation is 580g and the amount of targeted collector A added is 500g. (2) In step (1), targeted inhibitor A and targeted collector A are added sequentially to the primary desilication tailings to carry out secondary desilication operation, thereby obtaining secondary desilication concentrate and secondary desilication tailings; the secondary desilication tailings are flotation tailings I; based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added in the slurry of the secondary desilication operation is 290g and the amount of targeted collector A added is 250g. (3) After the primary desilication concentrate obtained in step (1) and the secondary desilication concentrate obtained in step (2) are combined, sodium sulfide, targeted inhibitor B and targeted collector B are added in sequence to carry out a primary decalcification operation to obtain a primary decalcification concentrate and a primary decalcification tailings. Based on each ton of siliceous calcium oxide copper ore, the amount of sodium sulfide added in the slurry of the primary decalcification operation is 1200g, the amount of targeted inhibitor B added is 400g, the amount of targeted collector B added is 360g, and the amount of foaming agent added is 30g. (4) In step (3), targeted inhibitor B and targeted collector B are added sequentially to the primary decalcification tailings to carry out secondary decalcification, thereby obtaining secondary decalcification concentrate and secondary decalcification tailings; the secondary decalcification tailings are flotation tailings II; based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added in the slurry of the secondary decalcification operation is 200g, the amount of targeted collector B added is 180g, and the amount of frother added is 15g; (5) The primary decalcified concentrate obtained in step (3) and the secondary decalcified concentrate obtained in step (4) are combined and then targeted inhibitor B and targeted collector B are added sequentially to perform a primary cleaning operation to obtain a primary cleaning concentrate and a primary cleaning tailings. The primary cleaning tailings are returned to the slurry and incorporated into the secondary decalcification operation. The amount of targeted inhibitor B added to the slurry of the primary cleaning operation is 100g and the amount of targeted collector B added is 45g per ton of siliceous calcium oxide copper ore. (6) After the primary concentrate obtained in step (5) is slurried, a secondary cleaning operation is carried out to obtain secondary concentrate and secondary tailings. The secondary tailings are returned to the slurry and incorporated into the primary cleaning operation. (7) The secondary concentrate obtained in step (6) is flotation copper concentrate. The flotation tailings I obtained in step (2) and the flotation tailings II obtained in step (4) are combined to obtain flotation tailings. In this embodiment, the copper flotation recovery rate was 86.7%.

[0022] The specific embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention.

Claims

1. A stepwise flotation method for desilication and decalcification of siliceous-calcium copper oxide ore, characterized in that, The specific steps are as follows: (1) Stir and adjust the slurry of siliceous calcium oxide copper ore to a slurry mass percentage concentration of 23-37%, then add targeted inhibitor A and targeted collector A in sequence to carry out one desilication operation, and obtain one desilication concentrate and one desilication tailings; (2) Targeted inhibitor A and targeted collector A are added sequentially to the primary desilication tailings obtained in step (1) to carry out secondary desilication operation, thereby obtaining secondary desilication concentrate and secondary desilication tailings; the secondary desilication tailings are flotation tailings I; (3) After the primary desilication concentrate obtained in step (1) and the secondary desilication concentrate obtained in step (2) are combined, sodium sulfide, targeted inhibitor B and targeted collector B are added in sequence to carry out a decalcification operation to obtain a primary decalcification concentrate and a primary decalcification tailings. (4) Targeted inhibitor B and targeted collector B are added sequentially to the primary decalcification tailings obtained in step (3) to carry out secondary decalcification, thereby obtaining secondary decalcification concentrate and secondary decalcification tailings; the secondary decalcification tailings are flotation tailings II; (5) After the primary decalcification concentrate obtained in step (3) and the secondary decalcification concentrate obtained in step (4) are combined, targeted inhibitor B and targeted collector B are added in sequence to perform a primary cleaning operation to obtain a primary cleaning concentrate and a primary cleaning tailings. The primary cleaning tailings are returned to the slurry and incorporated into the secondary decalcification operation. (6) After the primary concentrate obtained in step (5) is slurried, a secondary cleaning operation is carried out to obtain secondary concentrate and secondary tailings. The secondary tailings are returned to the slurry and incorporated into the primary cleaning operation. (7) The secondary concentrate obtained in step (6) is flotation copper concentrate. The flotation tailings I obtained in step (2) and the flotation tailings II obtained in step (4) are combined to obtain flotation tailings. The targeted inhibitor A is composed of water glass, 2-hydroxyethyl ether cellulose and naphthalene sulfonate formaldehyde condensate; the targeted inhibitor B is composed of tetrasodium diphosphate, fenugreek gum and tetrasodium hydroxyethylidene diphosphonate; the targeted collector A is composed of sodium oleate, oxidized paraffin soap and benzohydroxyoxime acid; the targeted collector B is composed of isopentyl xanthate, ethyl thiocyanate and aniline black; and the foaming agent is pine oil.

2. The step-flotation desiliconization and decalcification method for silica-calcium oxide copper ore according to claim 1, characterized in that: Step (1) The mass percentage of copper in the siliceous calcium oxide copper ore is 0.52~0.86%.

3. The step-flotation desiliconization and decalcification method for silica-calcium oxide copper ore according to claim 1, characterized in that: Based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added to the slurry in step (1) of the desilication operation is 360~580g, and the amount of targeted collector A added is 320~500g.

4. The step-flotation desiliconization and decalcification method for silica-calcium oxide copper ore according to claim 1, characterized in that: Based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor A added to the slurry in step (2) secondary desilication operation is 180~290g, and the amount of targeted collector A added is 160~250g.

5. The stepwise flotation desiliconization and decalcification method for silica-calcium oxide copper ore according to claim 1, characterized in that: For each ton of siliceous calcium oxide copper ore, the amount of sodium sulfide added to the slurry in step (3) of the first decalcification operation is 600~1200g, the amount of targeted inhibitor B added is 240~400g, the amount of targeted collector B added is 200~360g, and the amount of foaming agent added is 20~30g.

6. The step-flotation desiliconization and decalcification method for silica-calcium oxide copper ore according to claim 1, characterized in that: For each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added to the slurry in step (4) secondary decalcification operation is 120~200g, the amount of targeted collector B added is 100~180g, and the amount of foaming agent added is 10~15g.

7. The stepwise flotation desiliconization and decalcification method for silica-calcareous copper oxide ore according to claim 1, characterized in that: Based on each ton of siliceous calcium oxide copper ore, the amount of targeted inhibitor B added to the slurry in step (5) one-time beneficiation operation is 60~100g, and the amount of targeted collector B added is 25~45g.

8. The step-flotation desiliconization and decalcification method for silica-calcium oxide copper ore according to claim 1, characterized in that: Based on the mass fraction of the targeted inhibitor A as 100%, the targeted inhibitor A contains 40-60% water glass, 35-45% 2-hydroxyethyl ether cellulose, and 5-15% naphthalene sulfonate formaldehyde condensate; Based on the mass fraction of the targeted inhibitor B as 100%, the targeted inhibitor B contains 35-55% tetrasodium diphosphate, 30-40% fenugreek gum, and 15-25% tetrasodium hydroxyethylidene diphosphonate.

9. The stepwise flotation desiliconization and decalcification method for silica-calcareous copper oxide ore according to claim 1, characterized in that: Based on a mass fraction of 100% for targeted collector A, the content of targeted collector A is 30-50% sodium oleate, 30-40% oxidized paraffin soap, and 20-30% benzoyl hydroxyxamic acid; Based on a mass fraction of 100% for the targeted collector B, the targeted collector B contains 45-65% isopentyl xanthate, 20-30% ethyl thiocyanate, and 15-25% aniline black.

Images