Steel slag treatment device and process

Abstract

The application discloses a steel slag treatment process and equipment, and relates to the technical field of steel slag treatment, which comprises a separation pipe arranged at the outlet of a cyclone dust collector, a pressurizing part arranged between the separation pipe and the outlet of the cyclone dust collector, a spherical surface dust removal net and a metal spring plate arranged on the separation pipe, dust is intercepted when airflow passes through the dust removal net, and after the dust removal net is blocked, the air pressure in the separation pipe is increased to make the metal spring plate and the dust on the dust removal net shake off in a reverse bending mode, and a dust collecting cavity is arranged on the air inlet side of the dust removal net, the steel slag treatment process and equipment effectively separate steel materials from aggregates in steel slag through processes such as crushing, screening, sand making and magnetic separation, and are used for concrete or cement aggregate in the subsequent process, so that waste utilization is effectively realized, and the dust removal net of the secondary dust collector can change the state of the metal spring plate according to the change of air pressure, so that the dust removal net is adjusted and the blocked dust thereon is cleaned, thereby facilitating long-term use.

Description

Technical Field

[0001] This invention relates to the field of steel slag treatment technology, specifically to a steel slag treatment process and equipment. Background Technology

[0002] Steel slag, as a waste product generated during steel production, still contains a certain amount of iron and steel. Other components, such as calcium silicate formed by the oxidation of metal elements, can be used as cement, concrete, or roadbed materials, thus making waste utilization.

[0003] In the process of steel slag treatment, the aggregates mentioned above, which can be used as cement, concrete, or roadbed materials, generate a large amount of dust (extremely fine particles). This dust cannot be effectively removed by cyclone dust collectors alone, serving only as preliminary dust removal. Therefore, secondary dust removal is usually implemented after cyclone dust collection, such as electrostatic precipitators or bag filters. Both have relatively high dust removal rates, but electrostatic precipitators are expensive and sensitive to dust resistivity, requiring pretreatment (such as ammonia conditioning). Bag filters, on the other hand, are susceptible to corrosion from humidity and acidic / alkaline gases (requiring corrosion-resistant materials). Furthermore, incomplete cleaning can lead to "bag clogging," increasing pressure drop and resulting in relatively high costs. Therefore, we propose a steel slag treatment process and equipment. Summary of the Invention

[0004] The purpose of this invention is to provide a steel slag treatment process and equipment to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a steel slag treatment process and equipment, comprising the following steps:

[0006] Step 1: Raw material crushing. Steel slag enters the roller mill from the raw material silo for crushing, turning the raw material into granules.

[0007] Step 2: Screening. The particles crushed in Step 1 enter the screening drum. The screening drum has a double-layer screening structure, which divides the crushed particles into three parts: particles with a diameter of 4.5 mm or more, particles with a diameter of 1.0 mm or more but less than 4.5 mm, and particles with a diameter of less than 1.0 mm.

[0008] Step 3: Perform magnetic separation on particles with a diameter of 4.5mm or more. The magnetically separated steel particles enter the iron ore bin, while the non-steel particles form semi-finished aggregates or enter the raw material bin to circulate and form smaller particles.

[0009] Step four, sand making, is a parallel step to step three. Particles larger than 1.0 mm and smaller than 4.5 mm after screening in step two enter the sand making machine for sand making. After sand making, they enter the next step, while particles smaller than 1.0 mm directly enter the next step.

[0010] Step 5: Powder selection. The dust in the sand-making particles is discharged by wind power and enters the cyclone dust collector. The remaining aggregate particles undergo secondary magnetic separation. The steel particles after secondary magnetic separation enter the material bin, and the non-steel particles enter the fine aggregate bin for storage as concrete or cement additives.

[0011] Step 6: Secondary dust removal. The inlet of the secondary dust collector is connected to the outlet of the cyclone dust collector. Dust enters the secondary dust collector to separate the airflow and dust. The dust enters the dust silo for storage as raw material for commercial concrete.

[0012] Preferably, a steel slag treatment device includes a separation pipe disposed at the outlet of a cyclone dust collector. A pressurizing section is provided between the separation pipe and the outlet of the cyclone dust collector. The pressurizing section isolates and pressurizes the airflow at the outlet of the cyclone dust collector and delivers it to the separation pipe. A spherical dust removal screen and a metal spring are arranged sequentially in the direction of airflow inside the separation pipe. The dust removal screen and the metal spring are attached together, and their circumferential sidewalls are fixed to the inner wall of the separation pipe. When the airflow passes through the dust removal screen, it intercepts dust. After the dust removal screen is blocked, the air pressure in the separation pipe increases, causing the metal spring to bend in the opposite direction and shake off the dust on the dust removal screen. A dust collection chamber is provided on the air inlet side of the separation pipe located at the dust removal screen. A one-way valve that only allows air to exit is provided at the outlet end of the separation pipe.

[0013] Preferably, a Venturi tube is provided on the air inlet side of the separator tube located at the dust removal screen.

[0014] Preferably, the metal spring and the dust removal mesh are spherical surfaces that bulge towards the air inlet side.

[0015] Preferably, the metal spring and the dust removal screen are spherical surfaces protruding towards the air outlet side, and the circumferential sidewall of the metal spring is slidably limited to the separation tube, and the separation tube is provided with a baffle that contacts the middle position of the metal spring.

[0016] Preferably, the metal spring is a hollow frame spring.

[0017] Preferably, multiple sets of separation pipes can be provided for alternating air supply.

[0018] Preferably, the dustproof net is initially flat and is attached to one side of the metal spring sheet.

[0019] Preferably, the dust collection chamber is a tubular cavity with a wide opening facing into the separation tube and the other end extending downward.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] This invention effectively separates steel materials from aggregates in steel slag by crushing, screening, sand making, and magnetic separation. The aggregates are screened into corresponding diameter sizes so that they can be used in concrete or cement aggregates, thus effectively utilizing waste.

[0022] This invention provides a secondary dust collector after the cyclone dust collector. The dust collector's filter screen can change the state of the metal springs according to changes in air pressure, thereby adjusting the filter screen and cleaning the dust that clogs it, which is convenient for long-term use.

[0023] The dust removal net of the present invention, by means of a spherical surface, can adjust the gap of the surface in the thickness direction of the dust net when the air pressure changes after it becomes clogged, so that the pores on the clogged side are enlarged, thereby making it easier for dust to fall off and improving the efficiency of continuous use. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the process flow of the present invention;

[0025] Figure 2 A schematic diagram of the structure between the separator and the cyclone dust collector;

[0026] Figure 3 This is a schematic diagram of a half-section of the separation tube;

[0027] Figure 4 A schematic diagram of the half-section structure of the dust removal mesh and metal spring;

[0028] Figure 5 An embodiment of a frame structure for a metal spring clip;

[0029] Figure 6 Another embodiment of the frame structure for the metal spring sheet;

[0030] Figure 7 This is a schematic diagram of one embodiment of the pressurization section;

[0031] Figure 8 A schematic diagram of an embodiment in which the metal spring and dust removal screen protrude outwards towards the outlet of the separation pipe;

[0032] Figure 9 This is a schematic diagram showing the three states of a dust removal screen.

[0033] In the diagram: 1-Separation pipe; 2-Pressure section; 3-Dust removal screen; 4-Metal spring; 5-Dust collection chamber; 6-Venturi tube; 7-Baffle; 101-Outer cylinder; 102-Air inlet; 103-Cone; 104-Ash discharge port; 105-Inner cylinder. Detailed Implementation

[0034] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0035] Please see Figure 1-4 This invention provides a technical solution: a steel slag treatment process, comprising the following steps:

[0036] Step 1: Raw material crushing. Steel slag is conveyed from the raw material silo into the roller mill by an inclined belt. The roller mill crushes the blocky steel slag into granular form.

[0037] Step 2: Screening. The particles crushed in Step 1 enter the screening drum. The screening drum has a double-layer screening structure, that is, it has a screen structure with different screening mesh sizes. The crushed particles are screened into three parts: particles with a diameter of 4.5 mm or more, particles with a diameter of 1.0 mm or more but less than 4.5 mm, and particles with a diameter of less than 1.0 mm.

[0038] Step 3: After screening, a portion of the particles with a diameter exceeding 4.5mm is conveyed by a magnetic belt to separate the steel and non-steel materials. The steel materials are then recycled into the iron silo.

[0039] For non-ferrous materials with a particle diameter exceeding 4.5mm, they can be directly sent to another warehouse and sold as raw materials, or the material can be returned to the raw material warehouse and the steps one and two above can be repeated to break the particles into smaller particles.

[0040] Step 4, Sand Making: Step 4 is synchronized with Step 3. The particles from the other two parts screened in Step 2 are processed. Particles with a diameter of less than 1.0 mm can be directly transported to the classifier via conveyor belt or elevator because their diameter already meets the usage requirements.

[0041] For particles with a diameter of 1.0 mm or more but less than 4.5 mm, they are fed into a sand making machine, where they are accelerated and thrown by a high-speed rotating rotor or hammer. They collide and rub against the surrounding impact plates, liners, or other materials, and are eventually crushed into sand particles, i.e., the target particle diameter (diameter less than 1.0 mm). After crushing, the particles with a diameter less than 1.0 mm after screening are combined and transported to the air classifier by a conveyor belt or elevator.

[0042] Step 5: Powder selection. The dust in the sand-making particles is discharged by wind power and enters the cyclone dust collector. The remaining aggregate particles undergo secondary magnetic separation. The steel particles after secondary magnetic separation enter the material bin, and the non-steel particles enter the fine aggregate bin for storage as concrete or cement additives.

[0043] The powder selection process involves two steps. First, the dust (dust or powder with extremely fine particle diameter) in the sand-making particles is blown into the cyclone dust collector by a wind-powered mechanism through the powder classifier. The dust is separated from the airflow in the cyclone dust collector and then discharged as a dust-free airflow, thus achieving the purpose of environmental protection.

[0044] Another step is to perform secondary magnetic separation on the remaining aggregate particles after the air-powered mechanism blows them out from the classifier. This process removes the very small amount of steel material contained in the non-steel material particles after the first magnetic separation, effectively purifying the steel material in the steel slag and improving the effective utilization rate of the material.

[0045] Step 6: Secondary dust removal. The inlet of the secondary dust collector is connected to the outlet of the cyclone dust collector. Dust enters the secondary dust collector to separate the airflow and dust. The dust enters the dust silo for storage as raw material for commercial concrete.

[0046] By using two magnetic separation processes and powder separation, steel and non-steel materials can be effectively separated, and non-steel materials can be sorted into specific diameter sizes, which can then be used as raw materials for different materials.

[0047] See Figure 2 , Figure 3 and Figure 4 A steel slag treatment device includes a separation pipe 1 installed at the outlet of a cyclone dust collector. The cyclone dust collector mainly includes an outer cylinder 101, an air inlet 102 at the top of the outer cylinder 101, a cone 103 at the bottom of the outer cylinder 101, an ash discharge port 104 at the lower end of the cone 103, and a coaxial inner cylinder 105 inside the outer cylinder 101. The top of the inner cylinder 105 is an air outlet, which is connected to one end of the separation pipe 1 for discharge.

[0048] The separation pipe 1 is sequentially equipped with a pressurizing section 2, a dust removal screen 3, and a metal spring 4 along its airflow direction. The pressurizing section 2 isolates the airflow discharged from the inner cylinder 105 and delivers a fixed amount of air to the separation pipe 1 in a single batch. After isolation, the airflow in the separation pipe 1 is pressurized. After pressurization, the airflow is discharged after being removed by the dust removal screen 3. The dust removal screen 3 is a dust removal assembly, which can be simply understood as a filter element. The dust removal screen 3 intercepts the dust in the airflow, and the dust-free airflow is discharged. The side of the dust removal screen 3 near the outlet end of the separation pipe 1 is attached to the metal spring 4. The metal spring 4 has a spherical surface, and the dust removal screen 3 is attached according to the shape of the metal spring 4. A one-way valve is set at the outlet position of the separation pipe 1 to discharge only the airflow.

[0049] After being pressurized, the airflow will be quickly discharged from the dust collector 3. After long-term use, the dust collector 3 will be blocked by dust accumulation. After blockage, the subsequent airflow in the separator 1 will be pressurized to a higher pressure state, which will reach the critical state of deformation of the metal spring 4. This will cause the metal spring 4 to change from bulging towards one end of the separator 1 to bulging towards the other end. During the deformation process, the metal spring 4 is different from the continuous deformation and compression of the spring. After the metal spring 4 bends in the opposite direction, it will have a rapid pop-out state. This state will cause the dust blocking the dust collector 3 to be popped off, thereby achieving the purpose of automatic cleaning. Because the metal spring 4 needs to be deformed back and forth, it is made of metal materials with excellent elastic modulus and fatigue life, such as phosphor bronze (C5191), beryllium copper (C17200), and stainless steel (SUS301 / SUS304).

[0050] See Figure 3 and Figure 7 The pressurization unit 2 changes the state of the dust collector screen 3 and the metal spring 4 by pressurizing the airflow. The pressurization unit 2 can adopt various methods, such as... Figure 3 The piston structure shown intermittently interrupts air intake, and the piston's moving and compressing speed exceeds the airflow outflow speed at the dust collector screen 3, thus generating pressure. The diagram shows only one set of pistons; however, it can be configured with multiple alternating sets, with the airflow converging at the outlets of multiple separation pipes 1. Alternatively, it can be configured as follows: Figure 7 As shown, several telescopic plates rotate around an axis, and a spiral contraction-shaped contact surface is set at the outer end of the telescopic plates. As they rotate, the volume between two adjacent telescopic plates decreases and is pressurized. The separation pipe 1 connects to the cavity between two adjacent telescopic plates after pressurization. The outlet of the corresponding inner cylinder 105 is at least one space away from the separation pipe 1, so that the two are not directly connected due to the space between the telescopic plates. As the telescopic plates rotate (rotate in the direction of contraction), the airflow is pressurized. At the moment of connection with the separation pipe 1, the air pressure decreases. As it continues to advance, the airflow is pressurized again, thereby generating the force to deform the metal spring 4. If the dust removal net 3 is not blocked or is blocked in a small area, the metal spring 4 will not deform.

[0051] The metal spring 4 is preferably designed to be hollow, such as... Figure 5 The hollow structure shown is a regular hexagon, or as... Figure 6 The hollowed-out equilateral triangle structure shown can be any shape. The hollowed-out design avoids occupying too much cross-sectional space, which would affect the airflow of the dust removal mesh 3.

[0052] A reset mechanism is provided on the recessed side of the metal spring 4 in its initial state. The reset mechanism can be composed of a telescopic rod and a sensor. The sensor detects the deformation of the metal spring 4, and after deformation, the telescopic rod pushes the metal spring 4 to reset. Alternatively, the metal spring 4 can be reset by rotating a cam. The form is not limited.

[0053] The separation tube 1 is also provided with a dust collection chamber 5. The dust collection chamber 5 is located on one side of the dust removal screen 3 and close to the metal spring 4. It collects the dust that falls from the dust removal screen 3 due to the elastic action caused by the deformation of the metal spring 4, and has an outlet to transport and discharge it at regular intervals. Alternatively, the dust collection chamber 5 can be detached and removed and replaced after a certain period of collection. Furthermore, the dust collection chamber 5 is a tubular cavity with a wide opening facing into the separation tube 1 and the other end extending downward. The wide opening and inclined state make it easier for the dust in the separation tube 1 to fall into the dust collection chamber 5, and the downward extension of the dust collection chamber 5 can prevent the dust from being carried up again by the airflow.

[0054] Furthermore, a Venturi tube 6 is installed in the separation pipe 1 on the air inlet side of the dust removal net 3. By reducing the cross-sectional area, the airflow velocity can be increased, thereby causing the airflow to flow rapidly and generate turbulence, which then agitates in the space between the Venturi tube 6 and the dust removal net 3 in the separation pipe 1, and the dust is quickly captured by the dust removal net 3.

[0055] See Figure 3 and Figure 8 The dust collector screen 3 has two installation methods: it can protrude towards the inlet end of the separation pipe 1 or towards the outlet end of the separation pipe 1. Figure 3 The metal spring 4 protrudes towards the inlet end of the separation tube 1. This design is relatively simple; deformation of the metal spring 4 only requires increased pressure, and resetting only requires a slight push. The outer circumferential surface of the metal spring 4 can be directly fixed to the inner wall of the separation tube 1. Conversely, as... Figure 8 As shown, the metal spring 4 protrudes towards the outlet end of the separator tube 1. Because its deformation needs to be reversed, the outer peripheral edge of the metal spring 4 cannot be directly fixed to the inner wall of the separator tube 1. The outer peripheral edge of the metal spring 4 slides and is limited by the inner wall of the separator tube 1. In the initial state, the outer peripheral edge of the metal spring 4 is close to the inlet of the separator tube 1, and a baffle 7 is fixed in the separator tube 1. The baffle 7 is on the side of the metal spring 4 near the outlet end of the separator tube and is in contact with the surface of the metal spring 4 in the initial state. The contact position is limited to the middle of the metal spring 4, so that the airflow is restricted in the middle of the metal spring 4. The pressure mainly acts on the edge of the metal spring 4. As the dust collector 3 becomes blocked, the force increases, causing the metal spring 4 to appear as... Figure 8 The state indicated by the dashed line in the figure is that the outer periphery moves towards the outlet end of the separation tube 1;

[0056] See Figure 9As shown above, although the initial arrangement of the metal spring 4 protruding towards the outlet end of the separator tube 1 is more complex, it also has better results. Figure 9 Figure a1 shows a partially enlarged structure of the planar dust collector mesh 3. It is planar in shape, and the pore size on its material is relatively uniform. When it is attached to the spherical metal spring 4, the curved deformation of the planar dust collector mesh 3 causes changes in the pore size on the left and right sides of the mesh. Figure 9 In section a2, the pores on the air inlet side become smaller due to compression, while the opposite is true on the right side. Under these conditions, after dust adheres and clogs the filter, the pressure causes the dust collector mesh 3 to deform. Figure 9 As shown in state a3, the aperture on the left side becomes larger. This allows the metal spring 4 to better eject dust, enabling the dust removal mesh 3 to return to its initial state more closely, thereby improving the subsequent dust removal effect.

[0057] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0058] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A steel slag treatment device, characterized in that, A secondary dust collector is installed at and connected to the outlet of a cyclone dust collector, including a separation pipe (1) installed at the outlet of the cyclone dust collector. A pressurizing section (2) is provided between the separation pipe (1) and the outlet of the cyclone dust collector. The pressurizing section (2) isolates and pressurizes the airflow at the outlet of the cyclone dust collector and delivers it to the separation pipe (1). A spherical dust collection screen (3) and a metal spring (4) are arranged sequentially in the direction of airflow in the separation pipe (1). A reset mechanism is provided on the side of the metal spring (4) that is initially concave. The dust collection screen (3) and The metal spring (4) is attached, and the circumferential sidewalls of both are fixed to the inner wall of the separation tube (1). The metal spring (4) and the dust removal net (3) are spherical surfaces protruding towards the air inlet side. When the airflow passes through the dust removal net (3), it intercepts the dust. After the dust removal net (3) is blocked, the air pressure in the separation tube (1) increases, causing the metal spring (4) to bend in the opposite direction and shake off the dust on the dust removal net (3). A dust collection chamber (5) is provided on the air inlet side of the separation tube (1) located on the dust removal net (3). A one-way valve that only releases air is provided at the outlet end of the separation tube (1).

2. The steel slag treatment equipment according to claim 1, characterized in that: A Venturi tube (6) is provided on the air inlet side of the separation tube (1) located on the dust removal net (3).

3. The steel slag treatment equipment according to claim 1, characterized in that: The metal spring (4) is a hollow frame spring.

4. The steel slag treatment equipment according to claim 1, characterized in that: Multiple sets of separation pipes (1) can be provided for alternating air supply.

5. The steel slag treatment equipment according to claim 1, characterized in that: The dust collection chamber (5) is a tubular cavity with a wide opening facing into the separation tube (1) and extending downward at the other end.

6. The steel slag treatment equipment according to claim 1, characterized in that: The metal spring (4) and the dust removal net (3) are adjusted to be spherical surfaces protruding towards the air outlet side, and the circumferential sidewall of the metal spring (4) is adjusted to be limited and slidably set with the separation pipe (1), and the separation pipe (1) is provided with a baffle (7) that contacts the middle position of the metal spring (4).

7. A steel slag treatment process, based on the steel slag treatment equipment according to any one of claims 1-6, the treatment process comprising the following steps: Step 1: Raw material crushing. Steel slag enters the roller mill from the raw material silo for crushing, turning the raw material into granules. Step 2: Screening. The particles crushed in Step 1 enter the screening drum. The screening drum has a double-layer screening structure, which screens the crushed particles into three parts: particles with a diameter of 4.5 mm or more, particles with a diameter of 1.0 mm or more but less than 4.5 mm, and particles with a diameter of less than 1.0 mm. Step 3: Perform magnetic separation on particles with a diameter of 4.5mm or more. The magnetically separated steel particles enter the iron ore bin, while the non-steel particles form semi-finished aggregates or enter the raw material bin to circulate and form smaller particles. Step four, sand making, is a parallel step to step three. Particles larger than 1.0 mm and smaller than 4.5 mm after screening in step two enter the sand making machine for sand making. After sand making, they enter the next step, while particles smaller than 1.0 mm directly enter the next step. Step 5: Powder selection. The dust in the sand-making particles is discharged by wind power and enters the cyclone dust collector. The remaining aggregate particles undergo secondary magnetic separation. The steel particles after secondary magnetic separation enter the iron silo, and the non-steel particles enter the fine aggregate silo for storage as concrete or cement additives. Step 6: Secondary dust removal. The inlet of the secondary dust collector is connected to the outlet of the cyclone dust collector. Dust enters the secondary dust collector to separate the airflow and dust. The dust enters the dust silo for storage as raw material for commercial concrete.

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