A method for dry separation of slag from waste incineration power generation furnace
The slag is screened through dry selection method and air selection equipment, and combined with the sorting equipment to sort the target materials, solving the problems of complex slag sorting methods, large water consumption and low precious metal sorting efficiency, and achieving efficient and accurate sorting effects.
Patent Information
- Application Number
- CN202510004554.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-02
- Publication Date
- 2025-04-08
AI Technical Summary
The existing slag sorting method has complex processes, large water consumption, high sewage treatment costs, and low efficiency and accuracy of precious metal sorting.
The dry selection method is used to screen the slag at different particle levels, and the air selection equipment is used to replace the traditional jigging machine and shaker, and the target materials are sorted in combination with the sorting equipment.
It greatly reduces the water consumption during the slag sorting process, improves the sorting efficiency and sorting accuracy of the target materials, and reduces the tail material and labor cost of manual sorting.
Smart Images
Figure CN119771605A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of slag treatment, and in particular to a method for dry separation of slag from waste incineration power generation. Background Art
[0002] After the incineration of domestic waste to generate electricity, a large amount of slag will be produced, which contains a variety of non-ferrous metals such as iron, zinc, copper, and aluminum, a very small amount of precious metals such as gold and silver, and unburned materials such as ceramics and glass. In order to recycle various metals in the slag, a wet sorting method is usually used. The slag is crushed, magnetically separated, two-stage jigging, eddy current and shaker screened to separate non-ferrous metals such as iron, copper, and aluminum. The fine sand under the shaker screen is then manually sorted to obtain a very small amount of precious metals such as gold and silver.
[0003] The existing slag sorting method has a complicated process, consumes a lot of water during the sorting process, and has a high cost for sewage treatment. The efficiency and accuracy of sorting precious metals in the slag are both low. The reasons are mainly the following two aspects: First, the content of precious metals in the slag is extremely small, and the precious metals in the slag usually form mixed particles with non-metallic or other non-ferrous metals, and the accuracy of manual sorting is low; second, after multiple screenings of the slag, the final tailings particle size is less than 6mm, and most of the particles are about 3mm in size, which makes the efficiency of manual sorting low. Summary of the invention
[0004] The purpose of the embodiments of the present application is to provide a dry sorting method for waste incineration power generation slag, which can screen the slag into different particle sizes, and use sorting equipment to sort the target material in the slag, so that the slag sorting method process is changed from wet sorting to dry sorting, which greatly reduces the water consumption in the slag sorting process and improves the sorting efficiency and sorting accuracy of the target material.
[0005] In one aspect of an embodiment of the present application, a method for dry separation of waste incineration power generation furnace slag is provided, comprising: crushing the slag and performing magnetic separation to remove iron to obtain refined iron and coarse sand;
[0006] The coarse sand material is fed into a first-stage air separator for sorting to obtain low-density sand material, medium-density sand material, and high-density sand material;
[0007] The medium-density sand material is fed into a secondary air separator for sorting, and the obtained secondary high-density sand material is mixed with the high-density sand material and fed into a separator for sorting to sort out the target material.
[0008] Optionally, the crushing of the slag and magnetic separation to remove iron to obtain refined iron and coarse sand material comprises:
[0009] The slag is screened by a feeding belt into a drum screen to obtain a first-level screen oversize and a first-level screen undersize.
[0010] The first-stage undersize material and the crushed first-stage oversize material are mixed and then sorted to obtain coarse sand material and coarse iron material;
[0011] The coarse iron material is screened to obtain a secondary undersize material and a secondary oversize material containing refined iron, and the refined iron is temporarily stored.
[0012] Optionally, the medium-density sand material is fed into a secondary air separator for sorting, and the obtained secondary high-density sand material is mixed with the high-density sand material and fed into a separator for sorting to sort out the target material, including:
[0013] The secondary undersize material and the medium-density sand material enter the secondary air separator for sorting to obtain secondary low-density sand material, secondary medium-density sand material and secondary high-density sand material;
[0014] The high-density sand material is crushed by a crusher and then sieved to obtain a third-level oversize material and a third-level undersize material;
[0015] The target material is selected from the mixture of the third-stage screen material and the second-stage high-density sand material.
[0016] Optionally, the step of selecting the target material from a mixture of the third-stage screened material and the second-stage high-density sand material comprises:
[0017] After the third-stage screen material is mixed with the second-stage high-density sand material, the mixed material is subjected to iron removal;
[0018] The mixture after iron removal enters a separator to separate the target material.
[0019] Optionally, the sorting machine is a photoelectric sorting machine, and the target material is a precious metal.
[0020] Optionally, after the high-density sand material is crushed by a crusher and then sieved to obtain a third-level oversize material and a third-level undersize material, the method further comprises:
[0021] The third-stage undersize material is mixed with the second-stage medium-density sand material and iron is removed to obtain refined iron and temporarily store it; the tailings are returned to the second-stage air separator for further sorting;
[0022] The secondary low-density sand material of the secondary air separator absorbs iron to obtain iron sand, and the tailings are fine sand, which are temporarily stored separately.
[0023] Optionally, the mixing of the first-stage undersize material and the crushed first-stage oversize material and then sorting to obtain coarse sand material and coarse iron material comprises:
[0024] The first-stage undersize material and the crushed first-stage oversize material are mixed and then enter the sorting belt, and after magnetic sorting, sand material and iron material are obtained respectively, and the sand material and the iron material are respectively entered into the sand crusher and the iron crusher for crushing;
[0025] The crushed sand material and the crushed iron material are then subjected to magnetic separation to obtain the coarse sand material and the coarse iron material respectively.
[0026] Optionally, the coarse sand material is fed into a primary air separator for sorting to obtain low-density sand material, medium-density sand material, and high-density sand material, including:
[0027] The low-density sand material is screened into three materials with different particle sizes according to the particle size;
[0028] The three materials are separated into two stages to obtain refined aluminum, coarse slag and coarse sand respectively.
[0029] Optionally, the three materials are subjected to two-stage sorting to obtain refined aluminum, coarse slag and coarse sand respectively, including:
[0030] During two-stage sorting, materials with a particle size larger than the target particle size are sorted by eddy current to obtain refined aluminum and coarse slag, wherein the refined aluminum is transported to the aluminum temporary storage area by the refined aluminum conveyor belt, and the coarse slag is transported to the coarse slag temporary storage area by the coarse slag conveyor belt;
[0031] Materials with a particle size less than or equal to the target particle size are sorted by eddy current to obtain refined aluminum and coarse sand. The refined aluminum is transported to the aluminum temporary storage area by a conveyor belt, and the coarse sand is transported to the coarse sand temporary storage area by a coarse sand conveyor belt.
[0032] Optionally, the three materials include materials with a particle size ≥16 mm, a particle size between 3 mm and 16 mm, and a particle size ≤3 mm;
[0033] The target particle size is 3 mm ± 0.1 mm.
[0034] The dry sorting method of waste incineration power generation slag provided in the embodiment of the present application includes crushing the slag and then performing magnetic separation to remove iron to obtain refined iron and coarse sand; the coarse sand enters the first-level air separator for sorting to obtain low-density sand, medium-density sand, and high-density sand; the medium-density sand enters the second-level air separator for sorting, and the obtained second-level high-density sand is mixed with the high-density sand and enters the sorting machine for sorting to sort out the target material. The slag is screened at different particle sizes using air sorting equipment to reduce the water consumption, water use and sewage treatment costs for sorting. The use of sorting equipment to sort the target materials in the slag can improve the recognition accuracy and sorting efficiency, reduce the amount of tailings required for manual sorting, and reduce labor costs. BRIEF DESCRIPTION OF THE DRAWINGS
[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.
[0036] Figure 1 This is one of the schematic flow diagrams of the dry separation method for waste incineration power generation furnace slag provided in this embodiment;
[0037] Figure 2 This is the second flow chart of the dry separation method of waste incineration power generation furnace slag provided in this embodiment. DETAILED DESCRIPTION
[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application.
[0039] In the description of this application, it should be noted that the terms "inside", "outside", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the application is usually placed when in use, which is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application. In addition, the terms "first", "second", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance.
[0040] It should also be noted that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a direct connection, or an indirect connection through an intermediate medium, or it can be the internal communication of two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0041] The existing slag sorting process is complicated, the sorting process consumes a lot of water, the sewage treatment cost is high, and the sorting efficiency and accuracy of precious metals in the slag are low. The main reasons are as follows: 1. The content of precious metals in the slag is very small, and the precious metals in the slag usually form mixed particles with non-metallic or other non-ferrous metals, and the manual sorting accuracy is low; 2. After multiple screenings of the slag, the final tailings particle size is less than 6mm, and most of the particles are about 3mm in size, which makes the manual sorting efficiency low.
[0042] In view of this, in order to solve the above-mentioned problems, the embodiment of the present application provides a dry sorting method for waste incineration power generation slag, which uses air sorting equipment instead of traditional jigs and shaking tables to screen the slag into different particle sizes, and uses sorting technology to sort the target materials (such as precious metals) in the slag, so that the slag sorting process is changed from wet sorting to dry sorting, which greatly reduces the water consumption in the slag sorting process and improves the sorting efficiency and sorting accuracy of the target materials.
[0043] For details, please refer to Figure 1and Figure 2 As shown, the embodiment of the present application provides a method for dry separation of waste incineration power generation furnace slag, comprising:
[0044] Before step S100, slag loading is first performed: the slag is grabbed by a slag crane and placed into an incoming hopper, and then transported to the loading hopper via an incoming conveyor for loading.
[0045] S100: The slag is crushed and then magnetically separated to remove iron to obtain refined iron and coarse sand.
[0046] Specifically, first, the slag in the upper hopper enters the drum screen through the feeding belt for screening to obtain the first-level screen material and the first-level screen material. Among them, in one implementation of the present application, the first-level screen material is the material remaining in the drum screen after screening, and the first-level screen material is the material screened out from the drum screen after screening.
[0047] The first-stage screen material remaining in the drum screen is then de-ironized and crushed by a crusher to obtain the crushed first-stage screen material.
[0048] Then, the first-stage undersize material and the crushed first-stage oversize material are mixed and enter the sorting belt, and after magnetic sorting, sand material and iron material are obtained respectively. The sand material and iron material are respectively crushed in the sand crusher and iron crusher;
[0049] Finally, the sand crushed material and the iron crushed material are magnetically separated to obtain coarse sand material and coarse iron material respectively;
[0050] Among them, the coarse iron material is screened to obtain the secondary undersize material and the secondary oversize material with the composition of refined iron, and the refined iron is transported to the refined iron temporary storage area by the refined iron conveyor belt.
[0051] S110: The coarse sand material is sent into a first-level air separator for sorting to obtain low-density sand material, medium-density sand material, and high-density sand material.
[0052] The coarse sand material obtained in step S100 is sorted by a primary sorting process, and the material is sorted according to its particle size. The coarse sand material with a small particle size enters the upper layer of the air separator and becomes a low-density sand material, the coarse sand material with a medium particle size becomes a middle-layer material, and the coarse sand material with the largest particle size becomes a high-density sand material.
[0053] The secondary undersize material obtained in step S100 and the medium-density sand material in the primary air separator in step S110 enter the secondary air separator for sorting to obtain secondary low-density sand material, secondary medium-density sand material and secondary high-density sand material.
[0054] Similar to the first-level air separator, after sorting according to the particle size of the materials, the materials fall into the second-level low-density sand, second-level medium-density sand and second-level high-density sand of the second-level air separator respectively.
[0055] The high-density sand material in step S110 is crushed by a crusher and then screened by a drum screen to obtain a third-level screen upper material and a third-level screen lower material;
[0056] The tertiary screen material and the secondary medium-density sand material of the secondary air separator are absorbed by a permanent magnetic iron absorber to obtain refined iron, which is then transported to the refined iron temporary storage area for temporary storage; the tailings are returned to the secondary air separator for further sorting.
[0057] The secondary low-density sand material of the secondary air separator is absorbed by a permanent magnetic iron absorber to obtain iron sand, and the tailings are fine sand. The iron sand and fine sand are transported to the iron sand temporary storage area and the fine sand temporary storage area for temporary storage respectively.
[0058] In addition, in step S110, the low-density sand material in the first-stage air separator enters the drum screen and is screened into three materials with different particle sizes according to the particle size;
[0059] In one implementation of the present application, the materials are screened according to the particle size into three types: particle size ≥16 mm, particle size between 3 mm and 16 mm, and particle size ≤3 mm.
[0060] The three kinds of materials enter the eddy current separator for two-stage separation. The materials with particle size larger than the target particle size are separated by eddy current to obtain refined aluminum and coarse slag. The refined aluminum is transported to the aluminum temporary storage area by the refined aluminum conveyor belt, and the coarse slag is transported to the coarse slag temporary storage area by the coarse slag conveyor belt.
[0061] Materials with a particle size less than or equal to the target particle size are separated by eddy current to obtain refined aluminum and coarse sand. The refined aluminum is transported to the aluminum temporary storage area by a conveyor belt, and the coarse sand is transported to the coarse sand temporary storage area by a coarse sand conveyor belt.
[0062] Furthermore, according to the particle size range of the above implementation method, it can be confirmed that the target particle size is 3mm±0.1mm, and eddy current separation is performed to obtain fine aluminum, coarse sand and coarse slag respectively.
[0063] It can be seen that in the above steps, the material is first screened into three specifications of material according to the particle size through the drum screen, and the three specifications of the material are then sorted separately, and two levels of particle size materials are obtained according to the target particle size, that is, materials larger than the target particle size and less than or equal to the target particle size. The two levels of particle size materials can be separated by eddy current to obtain refined aluminum, coarse sand and coarse slag for temporary storage respectively.
[0064] In addition, it should be noted that the specific numerical value of the above-mentioned particle size is only an example given in the present application, and is not the only limitation of the particle size in the present application. Those skilled in the art will select the particle size according to actual needs.
[0065] S120: The medium-density sand material is sent to the secondary air separator for sorting, and the obtained secondary high-density sand material is mixed with the high-density sand material and sent to the separator for sorting to sort out the target material.
[0066] For example, the target material is a non-ferrous metal. Furthermore, when the sorting machine is a photoelectric sorting machine, the target material is a precious metal, and the precious metal is finally sorted. This application is described by taking the target material as a precious metal as an example:
[0067] In step S110, the coarse sand material enters the first-stage air separator for sorting, and the obtained high-density sand material is crushed by the crusher and then enters the drum screen for screening to obtain the third-stage screen upper material and the third-stage screen lower material;
[0068] In step S110-2, the tertiary screened material is mixed with the secondary medium-density sand material and iron is removed to obtain refined iron and temporarily store it. The tailings are returned to the secondary air separator for further sorting.
[0069] The material on the third-stage screen is mixed with the secondary high-density sand material of the secondary air separator in step S110-1 and iron is removed;
[0070] After iron removal, the location of precious metals is marked by photoelectric sorting, and finally the precious metals are selected manually.
[0071] On the other hand, in the above process, screening is usually performed by a drum screen, the drum of which is tiltedly installed on the frame, and the motor is connected to the drum through a coupling via a reducer to drive the drum to rotate around its axis. When the material enters the drum, the tilt and rotation of the drum causes the material on the screen surface to flip and roll, so that the material under the screen is discharged through the discharge port of the drum, and the material on the screen can remain in the drum.
[0072] There are two types of air separators. One is a cascade dry separator, which uses the coupling of wind and vibration to separate materials into layers according to density on the separation bed, and can obtain low-density sand, medium-density sand and high-density sand. In addition, there is another type of air separator, which discharges materials along the length of the equipment from high to low density under the coupling of wind and vibration, and can also obtain low-density sand, medium-density sand and high-density sand. The same is true for secondary air separators, which can obtain secondary low-density sand, secondary medium-density sand and secondary high-density sand.
[0073] Magnetic separation can be carried out by permanent magnetic magnets, which are used to actively separate ferromagnetic materials from non-magnetic materials and are used in situations where the material contains a lot of iron. The permanent magnetic magnet uses special permanent magnets with high coercive force and high remanence, such as "articulated iron boron", to form a composite magnetic system. When the granular material passes directly under the iron remover of the permanent magnetic magnet, the ferromagnetic material in the material is sucked up. Because the belt on the iron remover is constantly running, when the ferromagnetic material adsorbed on it passes through the non-magnetic area, it is scraped out by the iron parts on the belt, achieving the purpose of sorting the ferromagnetic material.
[0074] Eddy current separation uses an eddy current separator to separate materials. It can use the different electrical conductivities of materials for separation. When electronic waste scraps containing non-magnetic conductive metals (such as lead, copper, zinc, etc.) pass through an alternating magnetic field at a certain speed, these non-magnetic conductive gold scraps will generate induced eddy currents. Since the material flow and the magnetic field have a relative motion speed, there is a thrust on the metal material that generates the eddy current. This principle can be used to separate non-ferrous metal materials from the mixed material flow.
[0075] In summary, the dry sorting method of waste incineration power generation slag provided in the embodiment of the present application uses air sorting equipment instead of traditional jigs and shaking tables to screen the slag for different particle sizes, reducing the water consumption of traditional slag sorting and greatly reducing the cost of water and sewage treatment. The use of photoelectric sorting technology to sort the precious metals in the slag to replace manual identification can improve the recognition accuracy and sorting efficiency on the one hand, and reduce the amount of tailings required for manual sorting on the other hand, thereby reducing labor costs.
[0076] The above are only embodiments of the present application and are not intended to limit the scope of protection of the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the scope of protection of the present application.
Claims
1. A method for dry separation of waste incineration power generation furnace slag, characterized in that: include: The slag is crushed and then magnetically separated to remove iron to obtain refined iron and coarse sand; The coarse sand material is fed into a primary air separator for sorting to obtain low-density sand material, medium-density sand material, and high-density sand material; The medium-density sand material is fed into a secondary air separator for sorting, and the obtained secondary high-density sand material is mixed with the high-density sand material and fed into a separator for sorting to sort out the target material.
2. The method for dry separation of waste incineration power generation furnace slag according to claim 1, characterized in that: The method of crushing the slag and then performing magnetic separation to remove iron to obtain refined iron and coarse sand comprises: The slag is screened by a feeding belt into a drum screen to obtain a first-stage oversize material and a first-stage undersize material; The first-stage undersize material and the crushed first-stage oversize material are mixed and then sorted to obtain coarse sand material and coarse iron material; The coarse iron material is screened to obtain a secondary undersize material and a secondary oversize material containing refined iron, and the refined iron is temporarily stored.
3. The method for dry separation of waste incineration power generation furnace slag according to claim 2, characterized in that: The medium-density sand material is fed into a secondary air separator for sorting, and the obtained secondary high-density sand material is mixed with the high-density sand material and fed into a separator for sorting to sort out the target material, including: The secondary undersize material and the medium-density sand material enter the secondary air separator for sorting to obtain secondary low-density sand material, secondary medium-density sand material and secondary high-density sand material; The high-density sand material is crushed by a crusher and then sieved to obtain a third-level oversize material and a third-level undersize material; The target material is selected from the mixture of the third-stage screen material and the second-stage high-density sand material.
4. The method for dry separation of waste incineration power generation furnace slag according to claim 3, characterized in that The method of selecting the target material from the mixture of the third-stage screen material and the second-stage high-density sand material comprises: After the third-stage screen material is mixed with the second-stage high-density sand material, the mixed material is subjected to iron removal; The mixture after iron removal enters a separator to separate the target material.
5. The method for dry separation of waste incineration power generation furnace slag according to claim 1, 3 or 4, characterized in that , the sorting machine is a photoelectric sorting machine, and the target material is a precious metal.
6. The method for dry separation of waste incineration power generation furnace slag according to claim 3 or 4, characterized in that After the high-density sand material is crushed by a crusher and screened to obtain a third-level screen-over material and a third-level screen-under material, the method further comprises: The third-stage undersize material is mixed with the second-stage medium-density sand material and iron is removed to obtain refined iron and temporarily store it; the tailings are returned to the second-stage air separator for further sorting; The secondary low-density sand material of the secondary air separator absorbs iron to obtain iron sand, and the tailings are fine sand, which are temporarily stored separately.
7. The method for dry separation of waste incineration power generation furnace slag according to claim 2, characterized in that The mixing of the first-stage undersize material and the crushed first-stage oversize material and the separation to obtain coarse sand material and coarse iron material comprises: The first-stage undersize material and the crushed first-stage oversize material are mixed and then enter the sorting belt, and after magnetic sorting, sand material and iron material are obtained respectively, and the sand material and the iron material are respectively entered into the sand crusher and the iron crusher for crushing; The crushed sand material and the crushed iron material are then subjected to magnetic separation to obtain the coarse sand material and the coarse iron material respectively.
8. The method for dry separation of waste incineration power generation furnace slag according to claim 1, characterized in that: The coarse sand material is fed into a primary air separator for sorting to obtain low-density sand material, medium-density sand material, and high-density sand material, including: The low-density sand material is screened into three materials with different particle sizes according to the particle size; The three materials are separated into two stages to obtain refined aluminum, coarse slag and coarse sand respectively.
9. The method for dry separation of waste incineration power generation furnace slag according to claim 8, characterized in that: The three materials are subjected to two-stage sorting to obtain refined aluminum, coarse slag and coarse sand, respectively, including: During two-stage sorting, materials with a particle size larger than the target particle size are sorted by eddy current to obtain refined aluminum and coarse slag, wherein the refined aluminum is transported to the aluminum temporary storage area by the refined aluminum conveyor belt, and the coarse slag is transported to the coarse slag temporary storage area by the coarse slag conveyor belt; Materials with a particle size less than or equal to the target particle size are sorted by eddy current to obtain refined aluminum and coarse sand. The refined aluminum is transported to the aluminum temporary storage area by a conveyor belt, and the coarse sand is transported to the coarse sand temporary storage area by a coarse sand conveyor belt.
10. The method for dry separation of waste incineration power generation furnace slag according to claim 9, characterized in that: The three types of materials include materials with a particle size ≥16mm, a particle size between 3mm and 16mm, and a particle size ≤3mm; The target particle size is 3 mm ± 0.1 mm.