A method for desliming separation of a multi-stage hydrocyclone
By using a multi-stage hydrocyclone to classify coal slime by particle size and separate solids and liquids, the problem of coal slime recovery in existing technologies has been solved, achieving efficient utilization of coal resources and improved separation purity.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NANJING AOBO IND INTELLIGENCE TECH RES INST CO LTD
- Filing Date
- 2022-12-22
- Publication Date
- 2026-05-19
AI Technical Summary
Existing hydrocyclones are difficult to effectively recover coal slime in coal mining, leading to a waste of coal resources.
A multi-stage hydrocyclone is used to crush and grind minerals to form a slurry, which is then screened and introduced into the hydrocyclone. Centrifugal force is used to separate the slurry into underflow and overflow products. The overflow products are then subjected to particle size classification and solid-liquid separation to achieve effective recovery of coal slime.
It improves the utilization rate of coal mine resources, ensures the purity of coal slime separation and the rational utilization of tailings, reduces the interference of ultra-fine particle size on separation, and improves the desliming and separation effect of hydrocyclones.
Smart Images
Figure CN116174176B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of desliming and separation technology, and more specifically, to a method for desliming and separation using a multi-stage hydrocyclone. Background Technology
[0002] Desliming is the process of separating fine slime from coarse sand in mineral processing. Slime is a disruptive factor in any mineral processing method, directly affecting separation parameters and reagent consumption. Therefore, desliming is a crucial preparatory step for mineral processing methods such as gravity separation, magnetic separation, and flotation. Various equipment is available for desliming raw ore, such as small-diameter hydrocyclones, screen hydrocyclones, and rake thickeners.
[0003] Hydrocyclones are devices used to separate and remove heavier, coarse particles such as silt and sand from wastewater. They are also sometimes used for sludge dewatering. There are two types: pressure-type and gravity-type, and they are often constructed using a cylindrical structure or metal pipe. Water enters tangentially from the top of the structure (or metal pipe) under pressure or gravity. Under centrifugal force, the coarse, heavy particles are thrown against the vessel wall and rotate downwards, being discharged along with the resulting concentrated liquid. Smaller particles, after rotating to a certain extent, are discharged with a secondary upward vortex.
[0004] Based on the above, the inventors discovered that:
[0005] In coal mining, there may be slag containing a lot of coal slime. If the slag is left unattended or simply treated, a large amount of coal slime in the slag is easily wasted. Moreover, when using hydrocyclones for simple separation of slurry, it is difficult to extract the beneficial coal slime from the slag to a large extent, thus resulting in the waste of coal resources.
[0006] Therefore, in view of this, we study and improve the existing structure to provide a method for desliming and separating sludge using a multi-stage hydrocyclone, in order to achieve a more practical purpose. Summary of the Invention
[0007] 1. Technical problems to be solved
[0008] In view of the problems existing in the prior art, the purpose of this invention is to provide a method for desliming and separating coal slurry using a multi-stage hydrocyclone, which can effectively recover coal slurry from slag, extract the beneficial coal slurry portion from the slag to a large extent, and thus improve the utilization rate of coal resources.
[0009] 2. Technical Solution
[0010] To solve the above problems, the present invention adopts the following technical solution.
[0011] A method for desliming and separating sludge using a multi-stage hydrocyclone, comprising the following specific steps:
[0012] Step S1: Crush and grind the minerals, then mix them into water and stir them thoroughly to form a cement-containing slurry;
[0013] Step S2: Use a sieve to screen the cement slurry, and then use the slurry that passes through the sieve to keep it stirred again.
[0014] Step S3: Based on step S2, continue to add water, adjust the slurry ratio, and keep stirring to form the slurry to be treated;
[0015] Step S4: Select the hydrocyclone, install it stably, and then start the hydrocyclone;
[0016] Step S5: Based on step S3, introduce the cement-containing slurry into the hydrocyclone;
[0017] Step S6: Adjust the operating status of the hydrocyclone and control the flow rate of the cement slurry to be treated;
[0018] Step S7: Receive the effluent from different stages of the hydrocyclone and perform effluent testing on each stage;
[0019] Step S8: Based on step S7, for the unqualified output, select the discrimination criteria, select the slurry that can be reprocessed, re-import into step S1, and reselect the sieve aperture.
[0020] Step S9: Based on step S7, collect the qualified export products;
[0021] Step S10: Complete the desliming and sorting process.
[0022] Furthermore, in step S1, the volume ratio of the mixed minerals to the water ranges from 1:4 to 1:8.
[0023] Furthermore, in step S2, the mesh size of the selected sieve is ≤75mm.
[0024] Furthermore, in step S3, the content of the adjusted slurry is less than 100 g / L.
[0025] Furthermore, in step S5, a guide pipe is inserted into the center of the cylinder inside the hydrocyclone and a ore pipe is connected along the tangential direction to guide the slurry into the hydrocyclone from the connected ore pipe.
[0026] Furthermore, in step S6, the impeller speed of the selected hydrocyclone is 1800 r / min, the separation pressure of the hydrocyclone is 0.05-0.1 MPa, and a foaming agent is added, with octanol content in the foaming agent being 82 g / t.
[0027] Furthermore, in step S7, the effluent includes underflow product and overflow product, and the acceptable yield limit for the underflow product is a minimum of 70%, while the acceptable yield limit for the overflow product is a minimum of 30%.
[0028] Furthermore, the overflow products include primary particle size, secondary particle size and tertiary particle size, wherein the primary particle size is 0.5-3 mm, the secondary particle size is 0.2-0.5 mm, and the tertiary particle size is <0.2 mm.
[0029] Furthermore, in step S9, the primary, secondary, and tertiary particle sizes in the overflow product are concentrated and separated into solid and liquid components, respectively. The mass percentages of the primary, secondary, and tertiary particle sizes are calculated, and the clean coal is determined. The secondary and tertiary particle sizes are the clean coal standards, and a secondary screening is performed using an arc screen.
[0030] 3. Beneficial Effects
[0031] Compared with the prior art, the advantages of this invention are:
[0032] (1) In this scheme, when coal mining is carried out and slag containing coal slag is piled up, the slag is crushed and ground, and then water is used to form a slurry. The particle size of coarse particles is screened, and then the slurry is introduced into a hydrocyclone by tangential introduction to achieve centrifugal separation of the slurry by the hydrocyclone. The multi-stage hydrocyclone can separate the slurry into underflow product and overflow product, and the recovery rate of underflow product and overflow product is relatively large. At the same time, the overflow product can also be divided into primary particle size, secondary particle size and tertiary particle size. Among them, the secondary particle size and tertiary particle size are the standard of clean coal, realizing the effective recovery of coal slime in slag, extracting the beneficial coal slime part in slag to a large extent, thereby improving the utilization rate of coal resources.
[0033] (2) In this scheme, when the hydrocyclone is used for coal slime separation, the separated coal slime is analyzed and screened with slag particles of about 75 mm. In this process, the interference of the extremely fine particles in the material selection on the desliming separation can be reduced, and the desliming separation effect of the hydrocyclone can be improved. At the same time, after the primary, secondary and tertiary particles are concentrated and separated into solid and liquid, the slag can be effectively converted into usable coal slime, ensuring the separation purity of the coal slime and realizing the rational utilization of tailings. Attached Figure Description
[0034] Figure 1 This is a schematic diagram of the process of the present invention. Detailed Implementation
[0035] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.
[0036] Example:
[0037] Please see Figure 1 A method for desliming and separating sludge using a multi-stage hydrocyclone, the specific steps of which are as follows:
[0038] Step S1: Crush and grind the minerals, then mix them into water and stir them thoroughly to form a cement-containing slurry;
[0039] Step S2: Use a sieve to screen the cement slurry, and then use the slurry that passes through the sieve to keep it stirred again.
[0040] Step S3: Based on step S2, continue to add water, adjust the slurry ratio, and keep stirring to form the slurry to be treated;
[0041] Step S4: Select the hydrocyclone, install it stably, and then start the hydrocyclone;
[0042] Step S5: Based on step S3, introduce the cement-containing slurry into the hydrocyclone;
[0043] Step S6: Adjust the operating status of the hydrocyclone and control the flow rate of the cement slurry to be treated;
[0044] Step S7: Receive the effluent from different stages of the hydrocyclone and perform effluent testing on each stage;
[0045] Step S8: Based on step S7, for the unqualified output, select the discrimination criteria, select the slurry that can be reprocessed, re-import into step S1, and reselect the sieve aperture.
[0046] Step S9: Based on step S7, collect the qualified export products;
[0047] Step S10: Complete the desliming and sorting process.
[0048] See Figure 1 In step S1, the volume ratio of the mixed minerals to the water body ranges from 1:4 to 1:8.
[0049] Controlling the amount of water added in step S1 reduces water waste during slurry screening in step S2, while also facilitating the subsequent addition of water and controlling the slurry concentration.
[0050] See Figure 1 In step S2, the mesh size of the selected sieve is ≤75mm;
[0051] By controlling the particle size of minerals that can pass through the screen to ≤75mm, the impact of the weight of mineral particles on the desliming and separation of hydrocyclones can be reduced in the subsequent cement sorting process.
[0052] See Figure 1 In step S3, the content of the adjusted slurry is less than 100 g / L;
[0053] Add water according to the amount of minerals added to avoid pipe blockage when discharging mineral particles due to excessive mineral content during coal slime separation in the hydrocyclone. This also reduces the number of collisions between particles and the inner wall of the hydrocyclone, thus reducing the wear and tear on the hydrocyclone.
[0054] See Figure 1 In step S5, a diversion pipe is inserted into the center of the cylinder inside the hydrocyclone and a ore pipe is connected along the tangential direction to guide the slurry into the hydrocyclone from the connected ore pipe.
[0055] By controlling the direction of slurry introduction and utilizing the hydraulic diversion inside the hydrocyclone, the slurry enters tangentially under the action of centrifugal force, which can improve the efficiency of slurry separation.
[0056] See Figure 1 In step S6, the impeller speed of the selected hydrocyclone is 1800 r / min, the separation pressure of the hydrocyclone is 0.05-0.1 MPa, and a foaming agent is added at the same time, with octanol content in the foaming agent being 82 g / t.
[0057] Adding a bubbler to a hydrocyclone can enhance the separation effect of mineral particles from water during hydrocyclone operation.
[0058] See Figure 1 In step S7, the effluent includes underflow product and overflow product. The acceptable yield limit for underflow product is 70%, and the acceptable yield limit for overflow product is 30%.
[0059] Based on the yield rates of the underflow and overflow products, the separation effect of the hydrocyclone during desliming is determined, and based on the separation effect, it is determined whether the coal slime needs secondary treatment.
[0060] See Figure 1 The overflow products include primary, secondary and tertiary particle sizes. The primary particle size is 0.5–3 mm, the secondary particle size is 0.2–0.5 mm, and the tertiary particle size is <0.2 mm.
[0061] The overflow products include primary, secondary, and tertiary particle sizes, which allow for the classification, export, and storage of coal slime after hydrocyclone desliming. Based on the particle size of the primary, secondary, and tertiary particles, the appropriate utilization method for the coal slime can be selected.
[0062] See Figure 1 In step S9, the primary, secondary, and tertiary particle sizes in the overflow product are concentrated and separated into solid and liquid components, respectively. The mass percentage of the primary, secondary, and tertiary particle sizes is calculated, and the clean coal is determined. The secondary and tertiary particle sizes are the clean coal standards, and a secondary screening is performed using an arc screen.
[0063] The primary, secondary, and tertiary particle sizes are further processed to reach a usable level. Based on the standards for judging clean coal, a secondary screening is performed using an arc screen. The utilization rate of clean coal obtained by desliming and separation using a multi-stage hydrocyclone is improved.
[0064] When performing sludge separation using a multi-stage hydrocyclone:
[0065] First, the minerals are crushed and ground. Then, they are mixed with water at a volume ratio of 1:6 and stirred thoroughly to form a cement-containing slurry. The cement slurry is then screened using a sieve with a mesh size of ≤75mm. The slurry that passes through the sieve is stirred again. Water is then added to adjust the slurry ratio so that the content of the adjusted slurry is less than 100g / L, and stirring is continued to form the slurry to be processed.
[0066] Then select the hydrocyclone and install it stably. Then start the hydrocyclone, insert the diversion pipe into the center of the cylinder inside the hydrocyclone, and connect the ore pipe along the tangential direction to guide the slurry into the hydrocyclone from the connected ore pipe.
[0067] Then adjust the operating state of the hydrocyclone. During this process, the impeller speed of the selected hydrocyclone is 1800 r / min, the separation pressure of the hydrocyclone is 0.05~0.1 MPa, and a foaming agent is added at the same time. The amount of octanol in the foaming agent is 82 g / t.
[0068] Then, the effluent from different stages of the hydrocyclone is collected and tested separately. The effluent includes underflow and overflow products. The overflow products include primary, secondary, and tertiary particle sizes. The primary particle size is 0.5–3 mm, the secondary particle size is 0.2–0.5 mm, and the tertiary particle size is <0.2 mm. The minimum acceptable yield of the underflow product is 70%, and the minimum acceptable yield of the overflow product is 30%.
[0069] The process involves concentrating and separating primary, secondary, and tertiary particle sizes in the overflow product, calculating their mass percentages, determining the clean coal content, selecting unqualified effluents, establishing a discrimination standard, selecting slurry suitable for secondary processing, re-selecting the sieve aperture for secondary processing, and finally collecting the effluent mechanically.
[0070] This completes the desliming and separation process of coal slime using a multi-stage hydrocyclone.
[0071] The above description is merely a preferred embodiment of the present invention; however, the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and its improved concepts, should be covered within the scope of protection of the present invention.
Claims
1. A method for desliming and separating sludge using a multi-stage hydrocyclone, characterized in that: The specific steps are as follows: Step S1: Crush and grind the minerals, then mix them into water and stir them thoroughly to form a cement-containing slurry; Step S2: Use a sieve to screen the cement slurry, and then use the slurry that passes through the sieve to keep it stirred again. Step S3: Based on step S2, continue to add water, adjust the slurry ratio, and keep stirring to form the slurry to be treated; Step S4: Select the hydrocyclone, install it stably, and then start the hydrocyclone; Step S5: Based on step S3, introduce the cement-containing slurry into the hydrocyclone; Step S6: Adjust the operating status of the hydrocyclone and control the flow rate of the cement slurry to be treated; Step S7: Receive the effluent from different stages of the hydrocyclone and perform effluent testing on each stage; Step S8: Based on step S7, for the unqualified output, select the discrimination criteria, select the slurry that can be reprocessed, re-import into step S1, and reselect the sieve aperture. Step S9: Based on step S7, collect the qualified export products; Step S10: Complete desliming and sorting; In step S1, the volume ratio of the mixed minerals to the water body ranges from 1:4 to 1:
8. In step S5, a diversion pipe is inserted into the center of the cylinder inside the hydrocyclone and a ore pipe is connected along the tangential direction to guide the slurry into the hydrocyclone from the connected ore pipe. In step S6, the impeller speed of the selected hydrocyclone is 1800 r / min, the separation pressure of the hydrocyclone is 0.05-0.1 MPa, and a foaming agent is added at the same time, with octanol content in the foaming agent being 82 g / t. In step S7, the effluent includes underflow product and overflow product. The acceptable yield of underflow product is 70%, and the acceptable yield of overflow product is 30%. The overflow products include primary, secondary and tertiary particle sizes, with the primary particle size being 0.5–3 mm, the secondary particle size being 0.2–0.5 mm, and the tertiary particle size being <0.2 mm. In step S9, the primary, secondary, and tertiary particle sizes in the overflow product are concentrated and separated into solid and liquid components, respectively. The mass percentages of the primary, secondary, and tertiary particle sizes are calculated, and the clean coal is determined. The secondary and tertiary particle sizes are used as the clean coal standard, and a secondary screening is performed using an arc screen.
2. The method for desliming and separating sludge using a multi-stage hydrocyclone according to claim 1, characterized in that: In step S2, the mesh size of the selected sieve is ≤75mm.
3. The method for desliming and separating sludge using a multi-stage hydrocyclone according to claim 1, characterized in that: In step S3, the content of the adjusted slurry is less than 100 g / L.