Diamond synthesis rod separation method capable of recycling waste liquid and materials

Abstract

The invention discloses a diamond synthesis rod separation method capable of recycling waste liquid and materials, and relates to the technical field of diamond synthesis. In order to solve the problems of environmental pollution caused by discharge of waste gas, waste acid liquor and wastewater, low separation efficiency and large acid consumption in the existing separation process, the invention provides the following technical scheme: a diamond synthesis rod is sequentially subjected to the procedures of crushing, electrolysis, physical separation, magnetic separation and purification drying to obtain a pure diamond main product; meanwhile, two byproducts of catalyst metal and graphite are obtained; according to the method, waste gas and waste acid liquid generated in the electrolysis and acid leaching procedures are collected and treated in a unified mode, and all the waste gas and the waste acid liquid are recharged to the electrolysis procedure to serve as electrolyte supplement. A closed-loop circulation system of the waste liquid and the materials is constructed, the separation method is low in cost, the product purity is high, a green, environment-friendly and economic production mode is achieved, meanwhile, the production efficiency is improved, and the acid consumption is remarkably reduced.

Description

Technical Field

[0001] This invention relates to the field of diamond manufacturing technology, and specifically to a method for separating diamond synthetic rods through the recycling of waste liquid and materials. Background Technology

[0002] Diamond synthetic rods are intermediate products in the production of synthetic diamonds, primarily composed of diamond, graphite, and a catalyst metal as a synthesis medium. To separate and purify diamond particles from the synthetic rods, the industry's existing conventional methods typically involve three stages: The first stage is preliminary metal removal, where the diamond synthesis rod is first crushed into particles smaller than 8mm, and then most of the catalyst metal is removed using electrolysis or acid leaching. The second stage is graphite separation, where the material from the previous stage is ball-milled to remove the attached graphite, and then most of the graphite is separated using a shaking table. The third stage is fine purification, where acid leaching is used to further remove residual metal fragments and graphite from the surface of the diamond particles. Finally, the product is rinsed and dried to obtain a pure diamond product.

[0003] However, the above-mentioned conventional practices have serious technical flaws and environmental problems: 1. Severe environmental pollution: During the electrolysis and two acid leaching processes, a large amount of acidic gas is generated and directly emitted into the atmosphere; at the same time, these processes and the subsequent rinsing process also generate and discharge a large amount of waste acid water and wastewater, causing serious pollution to the water and soil environment.

[0004] 2. Low efficiency of core processes: The treatment effect of several steps in the existing process is incomplete. First, the electrolysis process only removes about 90% to 95% of the catalyst metal, leaving 5% to 10% of metal residue. Second, for recrystallized graphite with a precise structure and strong adhesion, ball milling and shaking table sorting are insufficient to completely peel and separate it.

[0005] 3. High subsequent treatment costs and secondary pollution: Due to the incomplete removal of metals and graphite in the early stage, the subsequent fine purification stage must use a large amount of strong acid for long-term soaking treatment. This not only significantly increases the cost of acid consumption, but more importantly, it directly leads to a sharp increase in the amount of acid gas and waste acid water generated, aggravating the environmental pollution problem.

[0006] Therefore, existing diamond separation technologies suffer from inherent contradictions between process efficiency, environmental impact, and production costs, necessitating an innovative, green, and environmentally friendly separation method to address these issues. Summary of the Invention

[0007] The purpose of this invention is to provide a method for separating diamond synthetic rods by recycling waste liquid and materials, so as to solve the problem of environmental pollution caused by waste, waste gas and wastewater generated by existing separation processes.

[0008] The technical solution of the present invention to solve the above-mentioned technical problems is as follows: A method for separating diamond synthesis rods from recycled materials includes the following steps: S1, Electrolysis: The diamond synthetic rod is electrolyzed, and the acidic waste gas generated by the electrolysis is treated to obtain the first waste acid solution; the electrolyzed material is rinsed and soaked to obtain the second waste acid solution. S2, Physical separation: Physical separation of materials after rinsing and soaking to obtain graphite liquid; S3, Magnetic separation: The material after physical separation is subjected to magnetic separation, and the diamond containing magnetic material that is screened out is returned to S1 for electrolytic treatment; S4, Purification: The non-magnetic material after magnetic separation is purified, and the acidic waste gas generated during purification is treated to obtain the first waste acid liquid; the third waste acid liquid generated during the purification process is collected. S5, Drying: The purified diamond is dried to obtain the product; and the first waste acid, the second waste acid, and the third waste acid are all recycled back to S1.

[0009] Furthermore, prior to step S1, the diamond synthesis rod is crushed into particles with a diameter of less than 8 mm.

[0010] Furthermore, in S1, the acidic waste gas is purified by spraying through a condensation tower to obtain the first waste acid liquid.

[0011] Furthermore, after electrolysis in S1, the process also includes collecting metal from the cathode plate of the electrolytic cell to obtain catalyst metal byproducts.

[0012] Furthermore, the physical separation in S2 includes sequential ball milling, shaking table sorting, and grinding and kneading.

[0013] Furthermore, in S2, the graphite liquid is separated by a filter press, and the resulting solid is a graphite byproduct that is collected. The separated water is treated and recycled.

[0014] Furthermore, in S2, the solid obtained from physical separation is a graphite byproduct and is collected.

[0015] Furthermore, the purification process in S4 includes acid soaking and washing.

[0016] The present invention has the following beneficial effects: 1. This invention eliminates the problems of acid gas, waste acid, and wastewater discharge during the production process through closed-loop recycling of waste gas and waste acid liquid and regeneration of process water. Simultaneously, by comprehensively recovering catalyst metals and graphite byproducts, it achieves zero solid waste discharge, thus solving serious environmental pollution problems.

[0017] 2. This invention significantly improves the physical separation efficiency of metal and graphite by adding grinding, kneading, and magnetic separation reprocessing steps. This greatly reduces the amount of acid required for subsequent chemical purification, effectively shortening the process time, reducing production costs, and improving the purity of the final product. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a method for separating diamond synthesis rods by recycling waste liquid and materials according to an embodiment of the present invention; Figure 2 This is a schematic diagram illustrating the principle of a diamond synthesis rod separation method for recycling waste liquid and materials, according to an embodiment of the present invention. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Details are as attached Figure 1 , 2 As shown in the figure, this invention provides a method for separating waste liquid from recycled diamond synthetic rods. The specific implementation steps of this invention are described in detail below, taking the processing of 1000 kg of diamond synthetic rods as an example: Pretreatment: Take 1000 kg of diamond synthetic rods and first perform crushing pretreatment. Use a non-destructive, dust-free crusher to crush the synthetic rods into particles with a diameter of less than 8 mm. The purpose of this step is to increase the specific surface area of ​​the material, thereby significantly improving the removal efficiency of catalyst metals in the subsequent electrolysis steps.

[0021] S1, Electrolysis: 1000 kg of crushed particulate material is loaded into an electrolytic cell for electrolysis treatment for 96 hours. This step aims to remove most of the catalyst metals through electrochemical methods. During this step, the following operations are performed simultaneously: 1. Waste Gas Collection and Treatment: Acidic waste gas generated during electrolysis is actively collected through pipelines and sent to a condensation tower. Inside the condensation tower, the acidic substances in the waste gas are absorbed and dissolved in the water by circulating water spray purification, forming the first waste acid solution, which is collected, while the purified clean air is discharged. This achieves zero waste gas emissions from the electrolysis process.

[0022] 2. Collection of rinsing and soaking waste liquid: After 96 hours of electrolysis, the material in the electrolytic cell is removed for rinsing and soaking. The waste acid water containing residual electrolytes generated in this process is completely collected as the second waste acid liquid.

[0023] 3. Collection of metal by-products: After removing the material, clean the cathode plate of the electrolytic cell, scrape off and collect the metal deposited on the cathode plate during the electrolysis process as a catalyst metal by-product.

[0024] S2, Physical separation: The material that has been rinsed and soaked is sent to the physical separation unit and processed sequentially as follows: Ball milling: The material is placed in a ball mill and milled for 3 hours. Through mechanical grinding and impact, the graphite layer attached to the surface of the diamond particles is loosened and detached, forming a mixture containing diamond, graphite and water.

[0025] Shaking table sorting: The mixture after ball milling is fed onto a shaking table. Utilizing the difference in specific gravity between diamond and graphite, with the assistance of water flow, most of the lighter graphite is separated to obtain diamond concentrate. At the same time, the separated graphite is collected in liquid form.

[0026] Grinding and kneading: The diamond concentrate separated by the shaking table undergoes grinding and kneading. This step is specifically designed for recrystallized graphite, which has a fine structure and strong adhesion, and is difficult to remove using ball mills and shaking tables. Through more precise mechanical forces, it is effectively peeled off from the diamond surface, further improving the purity of the diamond and reducing the burden on subsequent processes.

[0027] Water and graphite byproduct recovery: The large amount of graphite-containing water generated during ball milling and grinding / kneading is collected and pumped into a filter press. Through solid-liquid separation, the water is filtered out as purified water and returned to processes such as rinsing, soaking, ball milling, shaking, grinding, and kneading for reuse, achieving zero discharge of process wastewater. The solid filter cake, the graphite byproduct, is collected and packaged.

[0028] S3, Magnetic Separation: This process involves magnetically separating the milled and kneaded diamond concentrate. The magnetic separator divides the material into two parts: Non-magnetic materials: These are pure diamonds that are essentially free of catalytic metals, and they proceed to the next purification step.

[0029] Magnetic materials: These mainly refer to diamond particles that are magnetic because they still contain trace amounts of catalyst metal. This material will be collected and returned to the electrolytic cell in step S1 for further electrolytic treatment along with new raw materials. This step establishes a crucial internal material circulation system that effectively "corrects errors," separating and recirculating difficult-to-process materials in advance, thus preventing them from entering the subsequent acid leaching process and significantly reducing final acid consumption.

[0030] S4, Purification: The non-magnetic diamond material separated by magnetic separation is placed in an acid-resistant tank for final acid immersion to thoroughly remove any trace metal and graphite impurities that may be present. It is then washed.

[0031] During this step, the following waste liquid and waste gas collection operations are performed simultaneously: Waste gas collection: The acidic waste gas generated during the acid soaking process is also collected through pipelines and sent to the same condensation tower used in step S1 for treatment, and then incorporated into the first waste acid solution.

[0032] Waste washing liquid collection: The waste acid water generated from washing diamonds after soaking in acid solution is completely collected as the third type of waste acid liquid.

[0033] S5, Drying: The washed diamond particles are dried to obtain the main product of high-purity diamond particles.

[0034] Simultaneously, all the waste acid collected in the preceding steps—namely, the first waste acid from the condensation tower, the second waste acid from the rinsing and soaking, and the third waste acid from the washing—is pumped back to the electrolytic cell in step S1 as a replenishment of the electrolyte. Thus, all waste acid generated during the production process is utilized in a closed loop, achieving zero waste acid discharge.

[0035] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for separating diamond synthesis rods from waste liquid and recycled materials, characterized in that, Includes the following steps: S1, Electrolysis: The diamond synthetic rod is electrolyzed, and the acidic waste gas generated by the electrolysis is treated to obtain the first waste acid solution; the electrolyzed material is rinsed and soaked to obtain the second waste acid solution. S2, Physical separation: Physical separation of materials after rinsing and soaking to obtain graphite liquid; S3, Magnetic separation: The material after physical separation is subjected to magnetic separation, and the diamond containing magnetic material that is screened out is returned to S1 for electrolytic treatment; S4, Purification: The non-magnetic material after magnetic separation is purified, and the acidic waste gas generated during purification is treated to obtain the first waste acid liquid; at the same time, the third waste acid liquid generated during the purification process is collected. S5, Drying: The purified diamond is dried to obtain the product; and the first waste acid, the second waste acid, and the third waste acid are all recycled back to S1.

2. The method for separating diamond synthesis rods from waste liquid and recycled materials according to claim 1, characterized in that, Before step S1, the diamond synthetic rod is crushed into particles with a particle size of less than 8 mm.

3. The method for separating diamond synthesis rods from waste liquid and recycled materials according to claim 1, characterized in that, In step S1, the acidic waste gas is purified by spraying through a condensation tower to obtain the first waste acid liquid.

4. The method for separating diamond synthesis rods from waste liquid and recycled materials according to claim 1, characterized in that, After electrolysis in step S1, the process also includes collecting metal from the cathode plate of the electrolytic cell to obtain a catalyst metal byproduct.

5. The method for separating diamond synthesis rods from waste liquid and recycled materials according to claim 1, characterized in that, In S2, physical separation includes sequentially performing ball milling, shaking table sorting, and grinding and kneading.

6. The method for separating diamond synthesis rods from waste liquid and recycled materials according to claim 1, characterized in that, In step S2, the graphite liquid is separated by a filter press, and the resulting solid is a graphite byproduct that is collected. The separated water is treated and recycled.

7. The method for separating diamond synthesis rods from waste liquid and recycled materials according to claim 1, characterized in that, In step S2, the solid obtained from the physical separation is a graphite byproduct and is collected.

8. The method for separating diamond synthesis rods from waste liquid and recycled materials according to claim 1, characterized in that, In step S4, the purification process includes acid soaking and rinsing.

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