Wide-fraction material recovery method
By classifying and multi-stage flotation of tailings sludge, the problem of coarse clean coal being lost from the tailings sludge was solved, achieving efficient clean coal recovery and product quality improvement.
Patent Information
- Application Number
- CN202411584799.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-07
- Publication Date
- 2025-01-07
AI Technical Summary
During the flotation process of tailings slime, the coarse clean coal is often lost, resulting in low flotation yield and difficulties in product dewatering, blending, and sales. In particular, the tailings slime treatment efficiency is low.
Tailings slime is classified into slime of multiple particle size ranges and processed using different flotation equipment and processes, including flotation machines and flotation columns. Combined with multi-stage thickening and dewatering, concentration is adjusted and flotation reagents are added to achieve efficient recovery of clean coal.
By strictly controlling particle size and selecting appropriate flotation equipment, the loss of coarse coal particles during the flotation process is avoided, flotation efficiency and clean coal recovery rate are improved, and product quality and production efficiency are optimized.
Smart Images
Figure CN119259244A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of mineral recovery, and in particular to a method for recovering materials with a wide particle size. Background Art
[0002] At present, the technological process of coal preparation enterprises in my country is constantly improving. The widespread application of heavy medium cyclones has enabled coal preparation enterprises to generally achieve the best separation effect in the gravity separation stage. However, the coal flotation stage is complex due to the influencing factors and is greatly affected by the fluctuations in coal and rock conditions in underground mining.
[0003] As the main method for improving the quality and reducing impurities of fine-grained coal, flotation faces the problem of poor adaptability and low efficiency of difficult-to-select and difficult-to-float coal, which is mainly manifested in low flotation yield, difficulty in dehydration and blending of products, and especially the treatment of tailings, which seriously restricts the efficient and clean recovery of coal resources. For example, in the flotation treatment of tailings, the problem of coarse clean coal running out will occur due to the large size of the coal particles being floated and the wide flotation particle size. Summary of the invention
[0004] The object of the present invention is to provide a method for recovering materials with a wide particle size so as to solve the technical problem of coarse clean coal running out due to excessively wide particle size of tailing coal slime flotation.
[0005] In order to achieve the above object, the present invention provides the following technical solutions:
[0006] The present invention provides a method for recovering materials with a wide particle size, comprising:
[0007] Obtaining tail coal slime, and classifying the tail coal slime into a first coal slime and a second coal slime, wherein the particle size of the first coal slime is greater than the particle size of the second coal slime;
[0008] Classifying the second coal slime into a third coal slime and a fourth coal slime, wherein the particle size of the third coal slime is greater than the particle size of the fourth coal slime;
[0009] The third coal slime is subjected to a first flotation, and the fourth coal slime is subjected to a second flotation, wherein the first flotation adopts a flotation machine process, and the second flotation adopts a flotation column process;
[0010] The underflow product after the first flotation is concentrated and dehydrated to form a second tail coal product, and the overflow product after the second flotation is concentrated and dehydrated to form a second clean coal product.
[0011] According to at least one embodiment of the present invention, after obtaining tail coal slime and classifying the tail coal slime into first coal slime and second coal slime, the method further includes:
[0012] sorting the first coal slime into gangue material, first medium coal material and first clean coal material;
[0013] The gangue material, the first medium coal material and the first clean coal material are screened and dehydrated respectively to form a gangue product, a first medium coal product and a first material product.
[0014] According to at least one embodiment of the present invention, after the gangue material, the first medium coal material and the first clean coal material are screened and dehydrated respectively, the method further includes:
[0015] The undersize water and the centrifugal liquid formed in the screening and dehydration process are mixed with the second coal slime.
[0016] According to at least one embodiment of the present invention, after the second coal slime is classified into the third coal slime and the fourth coal slime, the third coal slime is subjected to the first flotation and before the fourth coal slime is subjected to the second flotation, the method further includes:
[0017] The concentration of the third coal slime is adjusted to 30 g / L to 80 g / L, the concentration of the fourth coal slime is adjusted to 40 g / L to 100 g / L, and flotation reagents are added to the third coal slime and the fourth coal slime.
[0018] According to at least one embodiment of the present invention, the flotation machine process uses a first flotation machine and a second flotation machine for flotation, and the method comprises:
[0019] The underflow product of the first flotation machine is concentrated and dehydrated to form a second tail coal product;
[0020] The overflow product of the first flotation machine is passed through the second flotation machine, and the underflow product of the second flotation machine is concentrated and dehydrated to form a second medium coal product;
[0021] The overflow product of the second flotation machine is dehydrated to form a second clean coal product.
[0022] According to at least one embodiment of the present invention, the concentration and dehydration includes a first-stage concentration and a second-stage concentration, and the method includes:
[0023] The overflow product of the first-stage flotation machine is subjected to the first-stage concentration and the second-stage concentration to form the second tail coal product.
[0024] According to at least one embodiment of the present invention, the concentration and dehydration further comprises centrifugal dehydration, and the method further comprises:
[0025] The underflow product of the second flotation machine is subjected to the first-stage concentration, the centrifugal dehydration and the second-stage concentration to form the second tail coal product.
[0026] According to at least one embodiment of the present invention, after the concentration and dehydration, the method further comprises:
[0027] The overflow product or centrifuge liquid after the first stage concentration, the centrifugal dehydration and the second stage concentration is subjected to the third stage concentration.
[0028] According to at least one embodiment of the present invention, after the overflow product or the centrifuge liquid after the first stage concentration, the centrifugal dehydration and the second stage concentration is subjected to a third stage concentration, the method further comprises:
[0029] The overflow product after the third stage concentration is added into the tailing coal slime to adjust the concentration of the tailing coal slime.
[0030] According to at least one embodiment of the present invention, a mechanical agitation flotation process is used to perform a first flotation on the third coal slime; and / or,
[0031] The fourth coal slime is subjected to second flotation by adopting a cyclone microbubble flotation process.
[0032] Among the one or more technical solutions provided in the exemplary embodiments of the present invention, at least one of the following beneficial effects can be achieved.
[0033] The wide-size material recovery method of the exemplary embodiment of the present invention, by first classifying the tailing coal slime into a first coal slime with a larger particle size and a second coal slime with a smaller particle size, removes the first coal slime with a larger particle size before entering the flotation stage, thereby preventing the coarse-size coal particles from being easily desorbed from the flotation foam during the flotation process and being lost in the bottom flow with the tailing coal, resulting in the flotation "coarseness" phenomenon of the coarse-grained clean coal.
[0034] Furthermore, the second coal slime with a smaller particle size is further classified into a third coal slime and a fourth coal slime, wherein the particle size of the third coal slime is larger than the particle size of the fourth coal slime. Furthermore, the third coal slime is floated by a flotation machine process, and the fourth coal slime is floated by a flotation column process, which can give full play to the advantages of the flotation machine and the flotation column processes, realize the collection of valuable combustibles (clean coal products or medium coal products), and improve the production and processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] The accompanying drawings illustrate exemplary embodiments of the present invention and together with the description serve to explain the principles of the present invention, and these drawings are included to provide a further understanding of the present invention and are incorporated in and constitute a part of this specification;
[0036] Figure 1 is a flowchart of a wide-size material recovery method according to an embodiment of the present invention;
[0037] Figure 2It is a schematic flow chart of a wide particle size material recovery method according to an embodiment of the present invention.
[0038] Figure numerals: 101, coal slime barrel; 102, first cyclone; 103, spiral separator; 104, first curved screen; 105, second curved screen; 106, high-frequency fine screen; 107, first high-frequency screen; 108, second high-frequency screen; 109, coal slime centrifuge; 201, second cyclone; 202, first slurry mixing barrel; 203, second slurry mixing barrel; 204, first flotation machine; 205, flotation column; 206, second flotation machine; 207, first filter press; 208, first stage tail coal concentrator; 209, medium coal concentrator; 210, horizontal dehydration centrifuge; 211, second stage tail coal concentrator; 212, purification concentrator; 213, second filter press. DETAILED DESCRIPTION
[0039] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.
[0040] Figure 1 : is a flowchart of a wide particle size material recovery method according to an embodiment of the present invention. Figure 1 As shown, a method for recovering wide particle size materials provided by an exemplary embodiment of the present invention includes the following steps.
[0041] Step 1001: Obtain tailing coal slime, and classify the tailing coal slime into first coal slime and second coal slime, wherein the particle size of the first coal slime is larger than the particle size of the second coal slime.
[0042] For the insufficiently recovered tail coal slime produced by the coking coal preparation plant, or the coal slime products produced by the thermal coal preparation plant without fine coal sorting process, they are transported and unloaded into the coal slime barrel 101 for preliminary slurry treatment, and an appropriate amount of circulating water is added to the coal slime barrel 101 to adjust the appropriate coal slime concentration.
[0043] In order to ensure the sorting accuracy in the subsequent links, the circulating water needs to use the overflow water of the purification concentrator 212 to ensure that the reagent residue and solid content in the circulating water are qualified. For the configuration of the coal slime concentration, a concentration meter and a matching controller can be added to the pipeline between the coal slime barrel 101 and the first cyclone 102 to achieve accurate real-time control of the concentration of the selected coal slime slurry.
[0044] Figure 2 Schematic diagram of a wide-size material recovery method according to an embodiment of the present invention. Figure 2As shown, the coal slime in the coal slime barrel 101 is pumped into the first cyclone 102 with a diameter of 0.250 mm, and is classified into the first coal slime with a diameter greater than 0.250 mm and the second coal slime with a diameter less than or equal to 0.250 mm. The second coal slime is the low-concentration overflow product of the first cyclone 102, and the first coal slime is the high-concentration underflow product of the first cyclone 102.
[0045] After classifying the tail coal slime into the first coal slime and the second coal slime, it also includes: sorting the first coal slime into gangue material, first medium coal material and first clean coal material; screening and dehydrating the gangue material, the first medium coal material and the first clean coal material respectively to form gangue products, the first medium coal products and the first material products.
[0046] For example, the high-concentration underflow product is discharged from the underflow port and flows into the spiral separator 103 below to separate the underflow product, i.e., the coarse coal slime, again.
[0047] The working principle of the spiral separator 103 mainly relies on the centrifugal force on the materials in the separation tank. The heavier materials will move inwards towards the spiral shaft, while the lighter materials will move towards the outside of the separation tank. After the materials are separated in the separation tank, they are separated from different discharging devices according to their size and weight to form a separated material flow.
[0048] The spiral separator 103 is provided with two-stage cutters to separate the coal slime flow into clean coal, medium coal and gangue flow, and then passes through corresponding removal equipment to separate the coarse coal slime.
[0049] For example, the first gangue material from the spiral separator 103 passes through the first curved screen 104 and the first high-frequency screen 107 to remove a large amount of fine coal slime and remove moisture. The final screened material has too high ash content and is not worth sorting, so it is shipped out as the first gangue product T1. The first clean coal material from the spiral separator 103 passes through the high-frequency fine screen 106 and the coal slime centrifuge 109 to remove fine coal slime and moisture, and is the final first clean coal product C1. The first medium coal material from the spiral separator 103 passes through the second curved screen 105 and the second high-frequency screen 108 to remove fine coal slime and moisture, and the final screened material is the first medium coal product M1.
[0050] Furthermore, the undersize water, centrifugal liquid, etc. after being processed by the first curved screen 104, the second curved screen 105, the first high-frequency screen 107, the second high-frequency screen 108, the high-frequency fine screen 106 and the coal slime centrifuge 109 still contain a large amount of fine particles of coal slime, and whether to enter the next stage of flotation separation can be selected according to the actual ash content.
[0051] In some embodiments, after the gangue material, the first medium coal material and the first clean coal material are screened and dehydrated respectively, the method further comprises: mixing the undersize water and centrifugal liquid formed in the screening and dehydration processes with the second coal slime for the next step of processing.
[0052] The above-mentioned undersize water, centrifugal liquid and overflow product of the first hydrocyclone 102 (less than or equal to 0.250 mm second coal slime) all enter the second hydrocyclone 201 for further classification, and then undergo flotation treatment in the corresponding flotation equipment. Based on this, the recovery method of the exemplary embodiment of the present invention can achieve strict control of coal slime particle size before the flotation process to avoid the influence of coarse-grained coal slime on the flotation effect and flotation accuracy.
[0053] It should be noted that Figure 2 The “+” shown in the figure means “larger than a certain particle size” during classification, “sinking matter, heavy product” during sorting and concentration, and “dehydrated product” during dehydration; the “-” shows “smaller than a certain particle size” during classification, “floating matter, light product” during sorting and concentration, and “removed water” during dehydration.
[0054] Step 1002: Classify the second coal slime into a third coal slime and a fourth coal slime, wherein the particle size of the third coal slime is larger than the particle size of the fourth coal slime.
[0055] The undersize water, centrifugal liquid, overflow product of the first hydrocyclone 102 and the second coal slime in step 1001 are used as the feed slurry. The slurry is classified in the second hydrocyclone 201 to form a fourth coal slime of less than or equal to 0.075 mm and a third coal slime of greater than 0.075 mm and less than 0.25 mm.
[0056] It should be noted that the above-mentioned classification particle sizes of 0.250 mm and 0.075 mm are only examples, and are not limitations on the classification particle sizes of the first cyclone 102 and the second cyclone 201 in the present invention, and can be adjusted according to actual needs.
[0057] Step 1003: the third coal slime is subjected to first flotation, and the fourth coal slime is subjected to second flotation, wherein the first flotation adopts a flotation machine process, and the second flotation adopts a flotation column 205 process.
[0058] In some embodiments, after the second coal slime is classified into the third coal slime and the fourth coal slime, the third coal slime is subjected to the first flotation and before the fourth coal slime is subjected to the second flotation, the concentration of the third coal slime is adjusted to 30g / L to 80g / L, the concentration of the fourth coal slime is adjusted to 40g / L to 100g / L, and corresponding flotation agents are added to the third coal slime and the fourth coal slime.
[0059] Specifically, the third coal slime is slurried in the first slurry mixing barrel 202, for example, a suitable proportion of clean water is added, and the coal slime concentration after slurry mixing is 40g / L-100g / L, optionally 60g / L, 70g / L, 80g / L, 90g / L; according to the actual coal slime flotation reagent, adjusting agent, collecting agent, frother and other flotation reagents are added into the stirring barrel to complete the pretreatment of the coal slime before flotation to achieve the expected flotation effect.
[0060] Before flotation, the fourth coal slime also enters the second slurry mixing barrel 203 for slurry mixing treatment, for example, adding clean water in an appropriate proportion, and the coal slime concentration after slurry mixing is 30g / L~80g / L, optionally 40g / L, 50g / L, 60g / L, 70g / L; according to the actual coal slime flotation reagent, adjusting agent, collecting agent, frother and other flotation reagents are added into the stirring barrel to complete the pretreatment of the coal slime before flotation to achieve the expected flotation effect.
[0061] It should be noted that, according to the actual flotation process, the above-mentioned flotation reagents can be added into the flotation machine or the flotation column 205 to achieve the expected flotation effect.
[0062] In some embodiments, the flotation process is carried out in a graded flotation manner, for example, flotation is carried out using a first flotation machine 204 and a second flotation machine 206, including: the bottom flow product of the first flotation machine 204 is concentrated and dehydrated to form a second tail coal product T2; the overflow product of the first flotation machine is passed through the second flotation machine 206, and the bottom flow product of the second flotation machine 206 is concentrated and dehydrated to form a second medium coal product M2; the overflow product of the second flotation machine 206 is dehydrated to form a second clean coal product C2.
[0063] The fourth coal slime after pretreatment enters the flotation column 205 for flotation, wherein the flotation column 205 can be a cyclone microbubble flotation column, the underflow product of the flotation column 205 is dehydrated by the concentration equipment as the second tail coal product T2, and the overflow product of the flotation column 205 is dehydrated by the first filter press 207 as the second clean coal product C2.
[0064] The pretreated third coal slime enters the first flotation machine 204 and the second flotation machine 206 for two-stage flotation. Specifically, the overflow product of the first flotation machine 204 is adjusted to a suitable concentration and fed into the second flotation machine 206 for secondary flotation. The underflow product of the first flotation machine 204 is dehydrated by a thickening device as the second tail coal product T2, and the underflow product of the second flotation machine 206 is dehydrated by a thickening device as the second middle coal product M2.
[0065] The overflow product of the second flotation machine 206 and the overflow product of the flotation column 205 are simultaneously fed into the first filter press 207 for dehydration treatment to obtain the final second clean coal product C2.
[0066] Since the particle size of the overflow product of the second flotation machine 206 (greater than 0.075mm and less than 0.25mm) is different from the particle size of the overflow product of the flotation column 205 (less than or equal to 0.075mm), the two clean coal products with different particle sizes are put into the first filter press 207 for dehydration together, which can avoid the first filter press 207 from having too small feed particle size, reducing the filter cake pore size, pore area and porosity, and increasing the proportion of small pores, which leads to too slow filtration speed; it also avoids the particles caused by the excessively large feed particle size to easily block the feed hose of the first filter press 207, or to easily gather in the filter plate boss area and damage the filter cloth. Based on this, compared with using different filter presses to filter the overflow product of the second flotation machine 206 and the overflow product of the flotation column 205, the exemplary embodiment of the present invention uses the same first filter press 207 to filter the two overflow products, which can save equipment while improving the filter press processing efficiency.
[0067] In some embodiments, the recovery method of an exemplary embodiment of the present invention further includes adjusting the particle size distribution of the third coal slime entering the flotation machine and the particle size distribution of the fourth coal slime entering the flotation column 205, so that a certain proportion, for example 20%, of the fourth coal slime is mixed into the third coal slime entering the flotation machine, and a certain proportion of the third coal slime is mixed into the fourth coal slime entering the flotation column 205.
[0068] In the above-mentioned flotation machine process and flotation column 205 process, the third coal slime is floated by a two-stage flotation process, and the fourth coal slime is floated by a flotation column 205. The applicant has found that the flotation of coal slime with a single particle size and a narrow particle size range not only has a slow flotation rate but also a low recovery rate of the flotation combustibles. By adding a certain proportion of the fourth coal slime to the third coal slime processed by the flotation machine and adding a certain proportion of the third coal slime to the fourth coal slime processed by the flotation column 205, the flotation effect of the flotation machine and the flotation column 205 can be improved.
[0069] In order to achieve the purpose of improving the flotation effect, the second cyclone 201 is different from the first cyclone 102. Through a control method, such as through a controller PLC, etc., the feed pressure, overflow pipe insertion depth, bottom flow port diameter and other parameters of the second cyclone 201 are controlled, so that a certain proportion of the fourth coal slime can be mixed into the third coal slime, and a certain proportion of the third coal slime can be mixed into the fourth coal slime.
[0070] For example, when the ratio of the overflow pipe diameter of the second cyclone 201 to the cylinder diameter of the second cyclone 201 is 0.3-0.6, a certain proportion, for example, 20% of the third coal slime can be added to the fourth coal slime by increasing the diameter of the overflow pipe orifice; reducing the insertion depth of the overflow pipe within the range of overflow pipe insertion depth / cyclone cylinder diameter of 0.5-1.5; reducing the diameter of the underflow pipe orifice within the range of underflow pipe diameter / cyclone cylinder diameter of 0.05-0.15; and reducing the feed pressure (feed speed).
[0071] In another optional embodiment, the flow rate of the corresponding drainage pipe is controlled by a control device (the drainage pipe is provided with a valve, and the valve is electrically connected to the control device), and a part of the third coal slime that should enter the first slurry mixing barrel 202 is drained into the second slurry mixing barrel 203 through the corresponding drainage pipe; a part of the fourth coal slime that should enter the second slurry mixing barrel 203 is drained into the first slurry mixing barrel 202 through the corresponding drainage pipe, so as to maximize the flotation effect of each of the flotation machine flotation process and the flotation column flotation process.
[0072] In the graded flotation process, 20% of the third coal slime is added to the fourth coal slime in the flotation column 205. The third coal slime can provide a carrier for the fourth coal slime, increase the collision probability between the flotation bubbles and particles, and improve the flotation effect of the fourth coal slime, so as to fully reflect the advantages of the cyclone microbubble flotation column for the flotation of the fourth coal slime. In the flotation machine process, 20% of the fourth coal slime is added to the third coal slime, which can promote the adhesion probability of the third coal slime and the bubbles after collision, and form stable third coal slime stable bubbles, avoid the desorption of clean coal in the third coal slime caused by the high turbulent flow field inside the mechanical stirring flotation machine, and significantly improve the flotation effect of the third coal slime.
[0073] Through the coordinated cooperation of the second cyclone 201, the flotation machine process, and the flotation column 205 process, the advantages of each device can be fully utilized to achieve the collection of valuable coal and avoid the loss of valuable components.
[0074] Step 1004: The underflow product after the first flotation is concentrated and dehydrated to form a second tail coal product T2, and the overflow product after the second flotation is concentrated and dehydrated to form a second clean coal product C2.
[0075] In some embodiments, Figure 2 As shown, the concentration and dehydration includes the first stage concentration and the second stage concentration, including: the overflow product of the first stage flotation machine is subjected to the first stage concentration and the second stage concentration to form the second tail coal product T2.
[0076] Exemplarily, the concentration and dehydration further includes centrifugal dehydration, and further includes: subjecting the underflow product of the second flotation machine 206 to first-stage concentration, centrifugal dehydration and second-stage concentration to form a second tail coal product T2.
[0077] In actual applications, the underflow of the first flotation machine 204 and the underflow of the flotation column 205 are both concentrated and precipitated through the first-stage tailings concentrator 208, and the overflow of the first-stage tailings concentrator 208 is fed into the second-stage tailings concentrator 211; the underflow of the first-stage tailings concentrator 208 and the underflow of the second-stage tailings concentrator 211 are dehydrated through the second filter press 213 to form the second tailings product T2.
[0078] The bottom flow of the second flotation machine 206 is concentrated and precipitated by the medium coal concentrator 209, and the bottom flow of the medium coal concentrator 209 is dehydrated by the horizontal dehydration centrifuge 210 to form the second medium coal product M2. The centrifuge liquid of the horizontal dehydration centrifuge 210 flows to the second tail coal concentrator 211 for concentration and precipitation.
[0079] like Figure 2 As shown, in some embodiments, after concentration and dehydration, the method further includes: subjecting the overflow product and / or centrifugal liquid after the first-stage concentration, centrifugal dehydration and the second-stage concentration to a third-stage concentration.
[0080] For example, the overflow product and / or centrifugal liquid after the above-mentioned first-stage concentration, centrifugal dehydration and second-stage concentration is clarified and purified by the purification concentrator 212, and the solid content and the residual amount of the reagent in the overflow water will not exceed the standard, and can be used as circulating water. For example, a part of the circulating water can be connected to the coal slime barrel 101 to adjust the feed concentration entering the first cyclone 102, thereby forming a closed-loop treatment of water circulation; the other part of the circulating water can be used for other water-consuming equipment in the coal preparation plant.
[0081] Based on this, compared with the existing technology, many coal preparation plants have excessively simplified the coal slime water treatment process, resulting in serious excess of solid content and reagent residue in clarified overflow water, which in turn causes continuous accumulation and circulation of production water in the coal preparation plants, causing deterioration of production conditions, serious reduction in the accuracy of the grading and sorting process, and continuous decline in product quality.
[0082] Illustratively, after the overflow product or centrifugal liquid after the first stage concentration, centrifugal dehydration and second stage concentration is subjected to the third stage concentration, the overflow product after the third stage concentration is added to the tailings slime to adjust the concentration of the tailings slime, for example, the concentration of the tailings slime is adjusted to 15% to 30%, optionally, 17%, 19%, 25%, 27%, 29%, etc.
[0083] In the recovery method of the exemplary embodiment of the present invention, through three-stage concentration or centrifugal treatment, step-by-step concentration and purification are carried out to achieve efficient sedimentation treatment of the coal slime water produced in the flotation stage under the condition of a multi-product structure, and to achieve the reasonable classification of coal slime and tail coal slime products in the coal slime water treatment stage; avoid the continuous accumulation and circulation of solid content and reagent residues in the production water of the coal preparation plant, causing the deterioration of production conditions; realize the first-level closed-loop recycling of the production water of the coal preparation plant, and ensure the long-term efficient and qualified production of the coal preparation plant.
[0084] It should be understood by those skilled in the art that the above embodiments are only for the purpose of clearly illustrating the present invention, and are not intended to limit the scope of the present invention. For those skilled in the art, other changes or modifications may be made based on the above disclosure, and these changes or modifications are still within the scope of the present invention.
Claims
1. A method for recovering wide-size material, characterized in that: include: Obtaining tail coal slime, and classifying the tail coal slime into a first coal slime and a second coal slime, wherein the particle size of the first coal slime is greater than the particle size of the second coal slime; Classifying the second coal slime into a third coal slime and a fourth coal slime, wherein the particle size of the third coal slime is greater than the particle size of the fourth coal slime; The third coal slime is subjected to a first flotation, and the fourth coal slime is subjected to a second flotation, wherein the first flotation adopts a flotation machine process, and the second flotation adopts a flotation column process; The underflow product after the first flotation is concentrated and dehydrated to form a second tail coal product, and the overflow product after the second flotation is concentrated and dehydrated to form a second clean coal product.
2. The recycling method according to claim 1, characterized in that: After obtaining the tail coal slime and classifying the tail coal slime into the first coal slime and the second coal slime, the recovery method further includes: sorting the first coal slime into gangue material, first medium coal material and first clean coal material; The gangue material, the first medium coal material and the first clean coal material are screened and dehydrated respectively to form a gangue product, a first medium coal product and a first material product.
3. The recycling method according to claim 2, characterized in that: After the gangue material, the first medium coal material and the first clean coal material are screened and dehydrated respectively, the recovery method further includes: The undersize water and the centrifugal liquid formed in the screening and dehydration process are mixed with the second coal slime.
4. The recycling method according to claim 3, characterized in that: After the second coal slime is classified into the third coal slime and the fourth coal slime, the third coal slime is subjected to the first flotation, and before the fourth coal slime is subjected to the second flotation, the recovery method further includes: The concentration of the third coal slime is adjusted to 30 g / L to 80 g / L, the concentration of the fourth coal slime is adjusted to 40 g / L to 100 g / L, and flotation reagents are added to the third coal slime and the fourth coal slime.
5. The recycling method according to claim 4, characterized in that: The flotation process uses a first flotation machine and a second flotation machine for flotation, and the recovery method further includes: The underflow product of the first flotation machine is concentrated and dehydrated to form a second tail coal product; The overflow product of the first flotation machine is passed through the second flotation machine, and the underflow product of the second flotation machine is concentrated and dehydrated to form a second medium coal product; The overflow product of the second flotation machine is dehydrated to form a second clean coal product.
6. The recycling method according to claim 5, characterized in that: The concentration and dehydration comprises a first-stage concentration and a second-stage concentration, and the recovery method further comprises: The overflow product of the first-stage flotation machine is subjected to the first-stage concentration and the second-stage concentration to form the second tail coal product.
7. The recycling method according to claim 6, characterized in that: The concentration and dehydration further comprises centrifugal dehydration, and the method further comprises: The underflow product of the second flotation machine is subjected to the first-stage concentration, the centrifugal dehydration and the second-stage concentration to form the second tail coal product.
8. The recycling method according to claim 7, characterized in that: After the concentration and dehydration, the method further comprises: The overflow product or centrifuge liquid after the first stage concentration, the centrifugal dehydration and the second stage concentration is subjected to the third stage concentration.
9. The recycling method according to claim 8, characterized in that: After the overflow product or the centrifuge liquid after the first stage concentration, the centrifugal dehydration and the second stage concentration is subjected to a third stage concentration, the method further comprises: The overflow product after the third stage concentration is added into the tailing coal slime to adjust the concentration of the tailing coal slime.
10. The recycling method according to any one of claims 1 to 9, characterized in that: The third coal slime is subjected to a first flotation by using a mechanical stirring flotation process; and / or the fourth coal slime is subjected to a second flotation by using a cyclone microbubble flotation process.