A method for selecting radioactive qualified tailings from rare earth niobium zirconium polymetallic rock ore

Abstract

The present application belongs to the technical field of mineral processing, and provides a method for selecting radioactive qualified tailings from rare earth containing niobium-zirconium polymetallic rock ore. The present application obtains strong magnetic separation tailings through strong magnetic separation of raw ore, and the strong magnetic separation tailings are classified and then subjected to gravity separation. Fine particle level gravity separation tailings are subjected to desliming, and the obtained slimes are radioactive waste. Different coarse particle level concentrates are mixed, then ground and subjected to gravity separation, and the gravity separation tailings slimes obtained are radioactive waste. The gravity separation tailings slimes and sand mixture and the fine particle level gravity separation tailings desliming slimes are combined and subjected to gravity separation scavenging. While zircon is separated, the tailings are classified on the equipment, radioactive tailing slimes and qualified tailing sand are produced, radioactive exempt tailings with a yield of more than 50% of the raw ore can be separated, the output of radioactive waste residue is greatly reduced, and the amount of radioactive waste is reduced.

Description

Technical Field

[0001] This invention relates to the field of mineral processing technology, and in particular to a method for extracting radioactive qualified tailings from rare earth niobium-zirconium polymetallic rock deposits. Background Technology

[0002] For valuable minerals in the raw ore, strong magnetic separation is commonly used for rare earth and niobium minerals. Further flotation and other beneficiation methods are then used to recover these minerals from the strong magnetic concentrate. The main valuable mineral in the strong magnetic tailings is zirconium, which is recovered through gravity separation. Although the content of radioactive elements increases in the strong magnetic concentrate during the strong magnetic separation process, the radioactivity of the strong magnetic tailings still does not meet the exemption criteria. According to mineralogical data, radioactive elements in the strong magnetic tailings mainly exist in isomorphous forms within zirconium minerals. The radioactivity of the gravity-separated tailings obtained after removing zirconium minerals from the strong magnetic tailings is further reduced, but still does not meet the exemption criteria, requiring special disposal as hazardous waste. Currently, there are no published studies on the reduction of radioactive waste. Summary of the Invention

[0003] In view of this, the object of the present invention is to provide a method for extracting radioactive qualified tailings from rare earth niobium-zirconium polymetallic rock deposits. The method of the present invention significantly reduces the yield of radioactive tailings.

[0004] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0005] This invention provides a method for extracting radioactive tailings from rare earth niobium-zirconium polymetallic rock deposits, comprising the following steps:

[0006] The raw ore is subjected to grinding and high-intensity magnetic separation in sequence to obtain high-intensity magnetic separation tailings;

[0007] The strong magnetic separation tailings were classified to obtain strong magnetic tailings with particle sizes of -0.045mm, +0.045 to -0.074mm, +0.074 to -0.1mm, +0.10 to -0.2mm, and +0.2mm, respectively.

[0008] The strongly magnetic tailings with particle sizes of -0.045mm, +0.045 to -0.074mm, +0.074 to -0.1mm, +0.10 to -0.2mm, and +0.2mm are subjected to gravity separation to obtain first gravity separation concentrate, first gravity separation tailings, second gravity separation concentrate, second gravity separation tailings, third gravity separation concentrate, third gravity separation tailings, fourth gravity separation concentrate, fourth gravity separation tailings, fifth gravity separation concentrate, and fifth gravity separation tailings in sequence.

[0009] The tailings from the first gravity separation are deslimed to obtain tailings sand and tailings mud from the first gravity separation.

[0010] The third, fourth and fifth concentration concentrates are combined and then regrinded and re-concentrated to obtain re-concentrated zirconium concentrate, re-concentrated tailings slime, re-concentrated tailings slime-sand mixture and re-concentrated tailings sand.

[0011] The mixture of the first gravity separation tailings sand and the second gravity separation tailings mud sand is combined and subjected to gravity separation and scavenging to obtain zircon middlings, scavenged tailings mud and scavenged tailings sand;

[0012] The first gravity separation tailings slime, the re-separation tailings slime, and the scavenging tailings slime are combined as radioactive tailings;

[0013] The first gravity separation concentrate, the second gravity separation concentrate, and the re-gravity separation zirconium concentrate are combined as zirconium concentrate;

[0014] The tailings from the second, third, and fourth gravity separations, the tailings from the re-gravity separation, and the scavenging tailings are combined as qualified tailings.

[0015] Preferably, when the radioactivity of the fifth gravity separation tailings fails to meet the standard, the fifth gravity separation tailings undergo post-processing, which includes: the fifth gravity separation tailings are sequentially ground and gravity separated to obtain zircon middlings, gravity separation tailings sand and gravity separation tailings slime.

[0016] Preferably, the fifth gravity separation tailings are ground to a fineness of -0.2 mm, accounting for 95%.

[0017] Preferably, the zircon middlings are combined, and the resulting zircon middlings are combined with the third, fourth and fifth gravity concentrates and then regrinded and re-concentrated.

[0018] Preferably, the raw ore is ground to a fineness of -0.074 mm, accounting for 30% to 70%.

[0019] Preferably, the background magnetic field strength of the strong magnetic separation is 1.0 to 3.0 T.

[0020] Preferably, the third, fourth, and fifth concentrates are combined and then regrinded to a fineness of -0.074 mm or more (30% to 90%) and -0.045 mm or more (30% to 90%).

[0021] Preferably, the desliming is carried out in a hydrocyclone.

[0022] Preferably, during the re-gravity separation process, the re-gravity separation tailings are self-classified on the equipment into re-gravity separation tailings mud, re-gravity separation tailings mud-sand mixture, and re-gravity separation tailings sand.

[0023] This invention provides a method for selecting radioactive qualified tailings from rare earth niobium-zirconium polymetallic rock deposits, comprising the following steps: grinding and high-intensity magnetic separation sequentially to obtain high-intensity magnetic separation tailings; classifying the high-intensity magnetic separation tailings to obtain high-intensity magnetic separation tailings with particle sizes of -0.045mm, +0.045~-0.074mm, +0.074~-0.1mm, +0.10~-0.2mm, and +0.2mm; subjecting the high-intensity magnetic separation tailings with particle sizes of -0.045mm, +0.045~-0.074mm, +0.074~-0.1mm, +0.10~-0.2mm, and +0.2mm to gravity separation, sequentially obtaining a first gravity separation concentrate, a first gravity separation tailings, a second gravity separation concentrate, a second gravity separation tailings, a third gravity separation concentrate, a third gravity separation tailings, and a fourth gravity separation concentrate. The process involves: first, fourth, and fifth gravity separation tailings; desliming the first gravity separation tailings to obtain first gravity separation tailings sand and first gravity separation tailings slime; combining the third, fourth, and fifth gravity separation concentrates and then regrinding and regravity separation to obtain regravity separation zirconium concentrate, regravity separation tailings slime, a mixture of regravity separation tailings slime and sand, and regravity separation tailings sand; combining the first gravity separation tailings sand and the regravity separation tailings slime and sand mixture for gravity separation and scavenging to obtain zirconium middlings, scavenged tailings slime, and scavenged tailings sand; combining the first gravity separation tailings slime, regravity separation tailings slime, and scavenged tailings slime as radioactive tailings; combining the first gravity separation concentrate, second gravity separation concentrate, and regravity separation zirconium concentrate as zirconium concentrate; and combining the second, third, and fourth gravity separation tailings, regravity separation tailings sand, and scavenged tailings sand as qualified tailings.

[0024] This invention uses strong magnetic separation of raw ore to obtain strong magnetic separation tailings. After classification, the strong magnetic separation tailings are subjected to gravity separation. The fine-grained gravity separation tailings are deslimed, and the resulting mud is used as radioactive waste. The coarse-grained concentrate is mixed, regrinded, and then gravity separated to obtain re-gravity separation tailings mud, which is also used as radioactive waste. The re-gravity separation tailings mud-sand mixture and the sand obtained from the first gravity separation tailings desliming are combined for gravity separation and scavenging. While gravity separating zirconium, the tailings are self-classified on the equipment to produce radioactive tailings mud and qualified tailings sand. It can separate radioactive exempt tailings with a yield of more than 50% of the raw ore, which greatly reduces the output of radioactive waste and achieves the reduction of radioactive waste. Attached Figure Description

[0025] Figure 1 A flowchart of a method for selecting radioactive qualified tailings from rare earth niobium-zirconium polymetallic rock ore provided by the present invention.

[0026] Figure 2 This is a schematic diagram of the different product bands obtained by re-sorting on a shaker. Detailed Implementation

[0027] Figure 1The following is a flowchart of the method for selecting radioactive qualified tailings from rare earth niobium-zirconium polymetallic rock ore provided by the present invention, in conjunction with... Figure 1 The method provided by the present invention will be described.

[0028] This invention provides a method for extracting radioactive tailings from rare earth niobium-zirconium polymetallic rock deposits, comprising the following steps:

[0029] The raw ore is subjected to grinding and high-intensity magnetic separation in sequence to obtain high-intensity magnetic separation tailings;

[0030] The strong magnetic separation tailings were classified to obtain strong magnetic tailings with particle sizes of -0.045mm, +0.045 to -0.074mm, +0.074 to -0.1mm, +0.10 to -0.2mm, and +0.2mm, respectively.

[0031] The strongly magnetic tailings with particle sizes of -0.045mm, +0.045 to -0.074mm, +0.074 to -0.1mm, +0.10 to -0.2mm, and +0.2mm are subjected to gravity separation to obtain first gravity separation concentrate, first gravity separation tailings, second gravity separation concentrate, second gravity separation tailings, third gravity separation concentrate, third gravity separation tailings, fourth gravity separation concentrate, fourth gravity separation tailings, fifth gravity separation concentrate, and fifth gravity separation tailings in sequence.

[0032] The first gravity separation tailings are deslimed to obtain first gravity separation tailings sand and first gravity separation tailings mud.

[0033] The third, fourth and fifth concentration concentrates are combined and then regrinded and re-concentrated to obtain re-concentrated zirconium concentrate, re-concentrated tailings slime, re-concentrated tailings slime-sand mixture and re-concentrated tailings sand.

[0034] The mixture of the first gravity separation tailings sand and the second gravity separation tailings mud sand is combined and subjected to gravity separation and scavenging to obtain zircon middlings, scavenged tailings mud and scavenged tailings sand;

[0035] The first gravity separation tailings slime, the re-separation tailings slime, and the scavenging tailings slime are combined as radioactive tailings;

[0036] The first gravity separation concentrate, the second gravity separation concentrate, and the re-gravity separation zirconium concentrate are combined as zirconium concentrate;

[0037] The tailings from the second, third, and fourth gravity separations, the tailings from the re-gravity separation, and the scavenging tailings are combined as qualified tailings.

[0038] Unless otherwise specified, all raw materials used in this invention are preferably commercially available products.

[0039] This invention involves sequentially grinding and magnetically separating the raw ore to obtain magnetically separated tailings.

[0040] In this invention, the raw ore is preferably a rare earth-containing niobium-zirconium polymetallic rock ore. In this rare earth-containing niobium-zirconium polymetallic rock ore, the mass content of rare earth oxides is preferably 0.3-1.5%, the mass content of niobium oxides is preferably 0.05-0.6%, the mass content of zirconium oxides is preferably 1-6%, and the radioactivity is preferably... 238 U、 226 Ra and 232 Th, the radioactivity of a single nuclide is >1 Bq / g.

[0041] In this invention, the raw ore is preferably ground to a fineness of -0.074 mm, accounting for 30% to 70%.

[0042] In this invention, the background magnetic field strength of the strong magnetic separation is preferably 1.0 to 3.0 T.

[0043] In this invention, the strong magnetic separation further yields a strong magnetic concentrate, which preferably includes rare earth elements and niobium. This invention does not specifically limit the processing method of the strong magnetic concentrate.

[0044] After obtaining the strong magnetic separation tailings, the present invention classifies the strong magnetic separation tailings to obtain strong magnetic tailings with particle sizes of -0.045mm, +0.045 to -0.074mm, +0.074 to -0.1mm, +0.10 to -0.2mm, and +0.2mm.

[0045] The present invention does not specifically limit the grading method, as long as it can grade the tailings of strong magnetic separation into the ideal particle size.

[0046] After classification, the present invention performs gravity separation on the strongly magnetic tailings with particle sizes of -0.045mm, +0.045 to -0.074mm, +0.074 to -0.1mm, +0.10 to -0.2mm, and +0.2mm respectively, to obtain first gravity separation concentrate, first gravity separation tailings, second gravity separation concentrate, second gravity separation tailings, third gravity separation concentrate, third gravity separation tailings, fourth gravity separation concentrate, fourth gravity separation tailings, fifth gravity separation concentrate, and fifth gravity separation tailings in sequence.

[0047] In this invention, the reselection device is preferably a shaking table or a spiral chute, more preferably a shaking table. In this invention, the spiral chute is preferably multiple spiral chutes used in series.

[0048] After obtaining the first gravity separation tailings, the present invention deslims the first gravity separation tailings to obtain first gravity separation tailings sand and first gravity separation tailings slime. In the present invention, the desliming is preferably carried out in a hydrocyclone.

[0049] After obtaining the third, fourth, and fifth concentration concentrates, the present invention combines the third, fourth, and fifth concentration concentrates and then performs regrinding and re-concentration to obtain re-concentrated zirconium concentrate, re-concentrated tailings slime, a mixture of re-concentrated tailings slime and sand, and re-concentrated tailings sand.

[0050] In this invention, the refmilled ore is preferably ground to a fineness of -0.074 mm accounting for more than 95%, and -0.045 mm accounting for 30% to 90%.

[0051] In this invention, the reselection is preferably performed on a shaker.

[0052] In this invention, the re-gravity separation process yields re-gravity zirconium concentrate and re-gravity tailings. The re-gravity tailings are self-classified on the equipment into re-gravity tailings slime, a mixture of re-gravity tailings slime and sand, and re-gravity tailings sand. The different product zoning diagrams are shown below. Figure 2 As shown.

[0053] like Figure 2 As shown in the diagram, products from zones A and B are zirconium concentrate from regravity separation, intended for further processing. Tailings are classified as mud and sand; products C and D are regravity separation tailings sand, meeting radioactivity standards. Product E is a mixture of regravity separation tailings mud and sand requiring further processing; product F is regravity separation tailings mud, intended for radioactive tailings treatment. The distinction between regravity separation tailings mud and regravity separation tailings sand should be based on visible particles (0.02–0.03 mm). Visibly visible particles are sand, while indistinguishable particles are mud.

[0054] In this invention, the third, fourth, and fifth concentration concentrates contain a large number of intergrowths and have low zircon grades. After regrinding, the zircon minerals are liberated and then subjected to re-gravity separation to obtain a re-gravity separated zircon concentrate with a higher grade.

[0055] After obtaining the first gravity separation tailings sand and the second gravity separation tailings mud mixture, the present invention combines the first gravity separation tailings sand and the second gravity separation tailings mud mixture for gravity separation and scavenging to obtain zircon middlings, scavenged tailings mud and scavenged tailings sand.

[0056] In this invention, the reselection and scanning are preferably performed on a shaking table. After the reselection and scanning, the resulting different product banding diagrams are shown below. Figure 2 As shown.

[0057] Specifically, in this process (reselection and sweeping), Figure 2 The products from zones A and B are zircon middlings, which are further processed into zircon products; the products from zones C and D are scavenged tailings sand, which are qualified tailings products that meet radioactivity standards; the products from zones E and F are scavenged tailings mud, which are treated together as radioactive tailings.

[0058] In this invention, the radioactivity level of the fifth gravity separation tailings is related to the grinding fineness of the raw ore. When the raw ore is ground coarsely, the radioactivity of the fifth gravity separation tailings cannot meet the standard; when the raw ore is ground finely, the radioactivity of the fifth gravity separation tailings can be exempted. Through testing, when the radioactivity of the fifth gravity separation tailings cannot meet the standard, this invention preferably performs post-processing on the fifth gravity separation tailings. The post-processing includes: sequentially grinding and gravity separation of the fifth gravity separation tailings to obtain zircon middlings, gravity separation tailings sand, and gravity separation tailings slime.

[0059] In this invention, the fifth gravity separation tailings are preferably ground to a fineness of -0.2 mm, accounting for 95%.

[0060] In this invention, the reselection and sweeping are preferably performed on a shaking table.

[0061] The obtained zircon middlings are preferably combined in this invention, and the resulting zircon middlings are combined with the third, fourth and fifth gravity concentrates and then regrinded and re-concentrated.

[0062] The present invention combines the first gravity separation tailings mud, the re-separation tailings mud, and the scavenging tailings mud into radioactive tailings.

[0063] The tailings from the second, third, and fourth gravity separations, the tailings from the re-gravity separation, and the scavenging tailings are combined as qualified tailings.

[0064] The present invention combines the first gravity concentrate, the second gravity concentrate, and the regravity concentrate into a zirconium concentrate.

[0065] The following detailed description, in conjunction with embodiments, illustrates the method for selecting radioactive qualified tailings from rare earth niobium-zirconium polymetallic rock deposits provided by the present invention. However, these descriptions should not be construed as limiting the scope of protection of the present invention.

[0066] Example 1

[0067] The crushed raw ore was ground to a fineness of -0.074mm (30%), and then subjected to high-intensity magnetic separation under a background magnetic field strength of 1.0T. The resulting high-intensity magnetic separation tailings were processed according to... Figure 1 The process shown is as follows: the +0.2mm coarse-grained gravity separation tailings (fifth gravity separation tailings) are refmilled to -0.2mm (95%) and then separated. The results are shown in Table 1.

[0068] Table 1 Results of strong magnetic-magnetic tailings gravity separation of raw ore / %

[0069]

[0070]

[0071] Table 1 shows that qualified tailings 238 U、 226 Ra、232 The Th radioactivity meets the standard of <1 Bq / g specified in the national standard GB20664-2006 "Limits of Natural Radioactivity in Non-ferrous Metal Mineral Products". 40 The K radioactivity meets the national standard GB20664-2006 standard of <10 Bq / g. In this embodiment, qualified tailings accounting for 61.12% of the raw ore can be obtained.

[0072] Example 2

[0073] The crushed raw ore is ground to a fineness of -0.074mm (60%), and then subjected to high-intensity magnetic separation under a background magnetic field strength of 1.0T. The tailings from the high-intensity magnetic separation are processed according to... Figure 1 The process shown is a graded gravity separation. The +0.2mm coarse-grained gravity separation tailings (fifth gravity separation tailings) are directly processed as qualified tailings without grinding. The results are shown in Table 2.

[0074] Table 2 Results of strong magnetic-magnetic tailings gravity separation of raw ore

[0075]

[0076] Table 2 data shows that qualified tailings 238 U、 226 Ra、 232 The Th radioactivity meets the standard of <1 Bq / g specified in the national standard GB20664-2006 "Limits of Natural Radioactivity in Non-ferrous Metal Mineral Products". 40 The K radioactivity meets the national standard GB20664-2006 standard of <10 Bq / g. In this example, qualified tailings accounting for 54.33% of the raw ore can be obtained.

[0077] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for extracting radioactive tailings from rare earth-containing niobium-zirconium polymetallic rock deposits, characterized in that, Includes the following steps: The raw ore is subjected to grinding and high-intensity magnetic separation in sequence to obtain high-intensity magnetic separation tailings; The strong magnetic separation tailings were classified to obtain strong magnetic tailings with particle sizes of -0.045mm, +0.045~-0.074mm, +0.074~-0.1mm, +0.10~-0.2mm, and +0.2mm, respectively. The strongly magnetic tailings with particle sizes of -0.045mm, +0.045~-0.074mm, +0.074~-0.1mm, +0.10~-0.2mm, and +0.2mm are subjected to gravity separation to obtain first gravity separation concentrate, first gravity separation tailings, second gravity separation concentrate, second gravity separation tailings, third gravity separation concentrate, third gravity separation tailings, fourth gravity separation concentrate, fourth gravity separation tailings, fifth gravity separation concentrate, and fifth gravity separation tailings in sequence. The first gravity separation tailings are deslimed to obtain first gravity separation tailings sand and first gravity separation tailings mud. The third, fourth and fifth concentration concentrates are combined and then regrinded and re-concentrated to obtain re-concentrated zirconium concentrate, re-concentrated tailings slime, re-concentrated tailings slime-sand mixture and re-concentrated tailings sand. The mixture of the first gravity separation tailings sand and the re-gravity separation tailings mud is combined and subjected to gravity separation and scavenging to obtain the first zircon middlings, scavenged tailings mud and scavenged tailings sand; The first gravity separation tailings slime, the re-separation tailings slime, and the scavenging tailings slime are combined as radioactive tailings; The first gravity separation concentrate, the second gravity separation concentrate, and the re-gravity separation zirconium concentrate are combined as zirconium concentrate; The tailings from the second, third, and fourth gravity separations, the tailings from the re-gravity separation, and the scavenging tailings are combined as qualified tailings.

2. The method according to claim 1, characterized in that, When the radioactivity of the fifth gravity separation tailings fails to meet the standard, the fifth gravity separation tailings undergo post-processing, which includes: the fifth gravity separation tailings are sequentially ground and gravity separated to obtain second zircon middlings, gravity separation tailings sand and gravity separation tailings slime.

3. The method according to claim 2, characterized in that, The fifth gravity separation tailings are ground to a fineness of -0.2mm, accounting for 95%.

4. The method according to claim 2, characterized in that, The first and second zircon middlings are combined, and the combined zircon middlings are then combined with the third, fourth and fifth gravity concentrates and subjected to regrinding and gravity separation.

5. The method according to claim 1, characterized in that, The raw ore is ground to a fineness of -0.074 mm, with 30% to 70% of the particles being fine.

6. The method according to claim 1, characterized in that, The background magnetic field strength of the strong magnetic separation is 1.0~3.0T.

7. The method according to claim 1, characterized in that, The third, fourth, and fifth concentrates are combined and then regrinded until the fineness is -0.074 mm or more (over 95%) and -0.045 mm (30% to 90%).

8. The method according to claim 1, characterized in that, The desliming process is carried out in a hydrocyclone.

9. The method according to claim 1, characterized in that, During the re-gravity separation process, the resulting re-gravity separation tailings are self-classified on the equipment into re-gravity separation tailings mud, re-gravity separation tailings mud-sand mixture, and re-gravity separation tailings sand.

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