A blast furnace slag removal device

Abstract

The invention discloses a blast furnace slag discharge device, comprising a slag discharge groove connected to a blast furnace slag outlet and a groove mouth arranged at the end of the slag discharge groove, a water spraying device is arranged below the groove mouth, molten slag is discharged from the blast furnace slag outlet, flows down through the slag discharge groove and the groove mouth, the slag flow is water quenched by the water flow sprayed by the water spraying device, and then enters a slag-water mixing tank below, the vertical height of the slag-water mixing tank and the groove mouth is 1-2m; the cross-sectional shape of the slag discharge groove and the groove mouth comprises a semicircular bottom and two side walls tangent to the semicircular bottom, and the two side walls are inclined outward respectively; a diversion block for dispersing the slag flow at the upper part of the groove mouth to both sides is fixedly arranged above the inside of the groove mouth, the invention can improve the water quenching effect, the obtained slag-water mixture has no large blocks, the operation is safe, and no slag cotton or slag fiber is generated, which is environmentally friendly; at the same time, the slag flow can be prevented from impacting the groove mouth and corroding the groove mouth.

Description

Technical Field

[0001] The invention relates to a blast furnace slag discharge device and belongs to the field of blast furnace slag discharge devices. Background Art

[0002] The blast furnace is the main equipment in ironmaking. Iron ore, coke and other ironmaking raw materials are added to the blast furnace for smelting to obtain molten iron and slag. The molten iron is discharged through the iron ditch, and the slag is discharged through the slag ditch.

[0003] The slag is quenched with a large amount of water in a hot melt state to limit its crystallization and granulate it, which can be made into fine-grained slag mainly composed of glass. It has potential hydraulic gelling properties, which can be manifested under the action of activators such as cement clinker, lime, gypsum, etc. Therefore, it is a high-quality cement raw material.

[0004] In the prior art, the slag in a high-temperature molten state usually flows to the slag-water mixing tank through the slag discharge ditch. There is a drop of 1 to 2 meters between the slag-water mixing tank and the outlet of the slag discharge ditch. The slag flows out from the ditch mouth of the slag discharge ditch to form an arc-shaped slag flow. The water spraying device below sprays water to the slag flow for water quenching. The formed slag-water mixture enters the slag-water mixing tank, and is separated from the slag and water to obtain cement raw materials through subsequent treatment. However, the cross-section of the slag discharge ditch and the slag mouth of the prior art is usually set to be circular, semicircular or rectangular. Such a structure makes the thickness of the middle part of the slag flow thicker after it flows out of the slag mouth. The water flow sprayed by the water spraying device is difficult to penetrate the thicker central part, so that the slag cannot be cooled quickly. There will be large pieces of slag in the granulated slag. Due to the large volume of the large pieces of slag, the internal heat cannot be cooled in time, and it is very easy to explode in the water, posing a safety hazard. There is also a method to solve the problem of water flow not being able to penetrate by increasing the pressure and flow rate of the water spraying device. However, increasing the pressure and flow rate of the water spraying device will, firstly, cause a waste of water resources and increase the power consumption of the water supply equipment; secondly, the high-pressure impact slag will produce a large amount of slag cotton or slag fiber, which will not only pollute the environment, but also affect the health of the operators.

[0005] In addition, the high-temperature slag has a strong scouring and erosion effect on the slag discharge ditch, especially the ditch mouth. After a certain period of time, the ditch mouth becomes shorter, which will prevent the slag from falling into the slag-water mixing tank. At the same time, it is possible to flow to the outlet pipe of the water spray device below and damage the outlet pipe of the water spray device. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a blast furnace slag discharge device, which mainly plays two roles: first, it can disperse the slag flow when it flows down from the groove mouth, and can penetrate the slag flow for water quenching without increasing the pressure of the water spraying device. The water quenching effect is good, and the obtained slag-water mixture has no large lumps, and the operation is safe. At the same time, no slag cotton or slag fiber will be generated, and it is environmentally friendly; second, it can prevent the slag flow from impacting the groove mouth and eroding the groove mouth.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0008] A blast furnace slag discharge device comprises a slag discharge groove connected to a blast furnace slag outlet and a groove mouth arranged at the end of the slag discharge groove, a water spray device is arranged below the groove mouth, molten slag is discharged from the blast furnace slag outlet, flows down through the slag discharge groove and the groove mouth, the slag flow is water quenched by the water flow sprayed by the water spray device, and then enters the slag-water mixing tank below, the vertical height between the slag-water mixing tank and the groove mouth is 1 to 2 meters;

[0009] The cross-sectional shape of the slag discharge groove and groove mouth includes a semicircular bottom and two side walls tangent to the semicircular bottom, and the two side walls are inclined outward respectively; a diversion block is fixedly arranged above the inside of the groove mouth to disperse the slag flow at the upper part of the groove mouth to both sides.

[0010] A further improvement of the technical solution of the present invention is that the angle between the two side walls of the slag discharge groove and the groove mouth and the outer horizontal plane is 45 to 60 degrees.

[0011] A further improvement of the technical solution of the present invention is that the diverter block includes a top surface, a bottom surface, two side surfaces and an end surface, the top surface and the bottom surface are planes composed of star-shaped lines containing only one sharp point, and the sharp point is facing the flow direction of the molten slag, the end surface is a trapezoidal plane, and the top edge length is 4 times the bottom edge length, and the side surface is set to be a smooth surface with a smooth transition from the top surface to the bottom surface.

[0012] A further improvement of the technical solution of the present invention is that the star line formula of the top surface is:

[0013]

[0014] The formula for the star line of the bottom surface is:

[0015]

[0016] A further improvement of the technical solution of the present invention is that the diverter block is fixed above the inside of the groove mouth through a fixing plate, the top surface of the diverter block is fixed to the bottom surface of the fixing plate, and the two ends of the bottom surface of the fixing plate are fixed to the top of the groove mouth.

[0017] A further improvement of the technical solution of the present invention is that the trench mouth comprises a trench mouth outer shell and a fire-resistant layer coated inside the trench mouth outer shell and capable of withstanding high temperatures.

[0018] A further improvement of the technical solution of the present invention is that a cooling water jacket with the same shape as the groove mouth and cooling water flowing inside is arranged on the outer side wall of the groove mouth shell, and a water inlet pipe is arranged on one side of the cooling water jacket and a water outlet pipe is arranged on the other side.

[0019] A further improvement of the technical solution of the present invention is that the water inlet pipe and the water outlet pipe are respectively arranged in the middle of the top surface of the side wall of the cooling water jacket.

[0020] A further improvement of the technical solution of the present invention is that a control valve is provided on the water inlet pipe.

[0021] Due to the adoption of the above technical solution, the technical progress achieved by the present invention is:

[0022] The present invention is provided with a special-shaped diverter block, the side of which has an arc, which is a star-shaped arc, and is bent toward both sides near the end face. Such a side shape allows the slag flow to flow very smoothly along the side until it is dispersed to both sides. The bent portion of the side close to the end face provides a dispersion force for the slag flow, so that the slag flow continues to disperse toward both sides after flowing out of the groove mouth. In addition, with the improvement of the shape of the groove mouth, the two side walls inclined outward allow the upper slag flow to begin to disperse toward both sides at the groove mouth. At the same time, combined with the side shape of the diverter block, the slag flow flowing out of the upper part of the groove mouth is just dispersed toward both sides, and the slag flow flowing out of the lower part of the groove mouth is located in the middle. The slag flow flowing out of the groove mouth is no longer cylindrical, but a thin layer with a relatively thin thickness and a relatively large width. The slag flow can be penetrated without increasing the pressure and flow rate of the water spraying device, and the pressure and flow rate of the water spraying device can even be reduced to achieve a better water quenching effect. The obtained slag-water mixture has no large lumps and is safe to operate. At the same time, no slag cotton or slag fiber is generated, which is friendly to operators and the environment.

[0023] The end face of the diverter block of the present invention is a trapezoidal plane, and the top edge length is 4 times the bottom edge length. Combined with the two side walls of the groove mouth inclined outward, the slag flow flowing in the groove mouth is dispersed to both sides the higher it is located. The shape of the diverter block is combined with the shape of the groove mouth, so that the slag flow in the thin layer shape flowing out of the groove mouth and falling into the water quenching range has basically the same thickness from the middle to the two ends without any faults.

[0024] The outer wall of the groove mouth of the present invention is provided with a cooling water jacket with cooling water flowing inside. The slag flow at the groove mouth is cooled to a certain extent while ensuring sufficient fluidity. Combined with the refractory layer coated on the inner wall, it can prevent the slag flow from impacting the groove mouth and eroding the groove mouth, avoid the groove mouth being shortened due to erosion, and avoid affecting the shape of the final outflowing slag flow and the landing point of the slag flow, prevent damage to the water outlet of the water spraying device, and avoid the slag flow from being unable to fall into the slag-water mixing tank, causing accidents. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a schematic diagram of the structure of the present invention;

[0026] Figure 2 It is a schematic diagram of the installation structure of the ditch mouth, the diverter block and the water spray device of the present invention;

[0027] Figure 3It is a top view schematic diagram of the ditch mouth and the diverter block of the present invention;

[0028] Figure 4 It is a structural schematic diagram of the diverter block of the present invention;

[0029] Among them, 1. slag discharge ditch, 2. ditch mouth, 2-1. ditch mouth shell, 2-2. refractory layer, 2-3. cooling water jacket, 2-4. water inlet pipe, 2-5. water outlet pipe, 2-6. control valve, 3. slag flow, 4. water spraying device, 5. slag-water mixing tank, 6. diverter block, 6-1. top surface, 6-2. bottom surface, 6-3. side surface, 6-4. end surface. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with embodiments:

[0031] Embodiment 1:

[0032] like Figure 1 As shown, a blast furnace slag discharge device comprises a slag discharge groove 1 connected to the blast furnace slag outlet and a groove mouth 2 arranged at the end of the slag discharge groove 1, and a water spray device 4 is arranged below the groove mouth 2. The molten slag is discharged from the blast furnace slag outlet, flows down through the slag discharge groove 1 and the groove mouth 2, and the slag flow 3 is quenched by the water flow sprayed by the water spray device 4, and then enters the slag-water mixing tank 5 below to obtain the required slag particles. And the vertical height between the slag-water mixing tank 5 and the groove mouth 2 is 1 to 2 meters.

[0033] like Figure 2 and 3 As shown, the cross-sectional shape of the slag discharge groove 1 and the groove mouth 2 includes a semicircular bottom and two side walls tangent to the semicircular bottom, and the two side walls are inclined outwards respectively, and the angle between the two side walls of the slag discharge groove 1 and the groove mouth 2 and the outer horizontal plane is limited to 45-60 degrees. A diverter block 6 for dispersing the slag flow 3 at the upper part of the groove mouth to both sides is fixedly arranged above the inside of the groove mouth 2 by a fixing plate.

[0034] like Figure 3 As shown, the diverter block 6 includes a top surface 6-1, a bottom surface 6-2, two side surfaces 6-3 and an end surface 6-4. The top surface 6-1 of the diverter block 6 is fixed to the bottom surface of the fixed plate, and the two ends of the bottom surface of the fixed plate are fixed to the top of the groove mouth 2. The top surface 6-1 and the bottom surface 6-2 are planes composed of star-shaped lines containing only one sharp point, and the sharp point faces the flow direction of the molten slag. The end surface 6-4 is a trapezoidal plane, and the top edge length is 4 times the bottom edge length. The side surface 6-3 is set as a smooth surface that smoothly transitions from the top surface 6-1 to the bottom surface 6-2.

[0035] like Figure 3 The coordinates shown, the star line formula of the top surface 6-1 is:

[0036]

[0037] The star line formula for the bottom surface 6-2 is:

[0038]

[0039] The thickness of the slag flow obtained in this embodiment becomes 1 / 3 of the original one, and the width is doubled on both sides. At the same time, the pressure and flow of the water spraying device are reduced, and the sprayed water flow can still penetrate the slag flow, which improves the water quenching effect, so that there are no large pieces of water slag in the slag-water mixing tank, all of which are fine-grained water slag, and the vitrification rate of the water slag reaches 98%; and there is no slag wool or slag fiber, and the quality of the obtained water slag reaches special grade. Compared with circular, semicircular or rectangular slag discharge grooves and slag nozzles without diverter blocks, the water pressure of the water spraying device is reduced by 30%, and the power consumption is reduced by 40%, which greatly reduces the production cost.

[0040] The present embodiment is provided with a special-shaped diverter block, the side of which has an arc, which is a star-shaped arc, and is bent toward both sides near the end face. Such a side shape allows the slag flow to flow very smoothly along the side until it is dispersed to both sides. The curved portion of the side close to the end face provides a dispersion force for the slag flow, so that the slag flow continues to disperse toward both sides after flowing out of the groove mouth. In addition, with the improvement of the groove mouth shape, the two side walls inclined outward allow the upper slag flow to begin to disperse toward both sides at the groove mouth. Combined with the side shape of the diverter block, the slag flow flowing out of the upper part of the groove mouth is just dispersed toward both sides, and the slag flow flowing out of the lower part of the groove mouth is located in the middle. The slag flow flowing out of the groove mouth is no longer cylindrical, but a thin layer with a relatively thin thickness and a relatively large width.

[0041] After many control experiments, the angle between the two side walls of the slag discharge groove 1 and the groove mouth 2 and the outer horizontal plane must be 45-60 degrees. If the angle is too large, the thickness of the slag flow on both sides is small, the thickness in the middle is large, and the thickness of the slag flow layer is uneven. The water spray device must be set to a water pressure that can penetrate the thick slag flow, resulting in a waste of water resources; if the angle is too small, the thickness dispersed to both sides is large, the thickness in the middle is small, and the thickness is still uneven.

[0042] The side curvature of the diverter block also adopts a curvature of 1 / 4 circle. Such a curvature makes the slag flows on both sides not dispersedly spread to both sides after flowing down from the groove mouth 2, but form slag flow columns that cannot be spread. The final slag flow thickness is wavy and uneven.

[0043] The end face of the diverter block is a trapezoidal plane, and the length of the top edge is 4 times that of the bottom edge. Combined with the two side walls of the groove mouth inclined outward, the slag flow flowing in the groove mouth is dispersed to both sides the higher it is located. The shape of the diverter block is combined with the shape of the groove mouth, so that the slag flow in the thin layer flowing out of the groove mouth and falling into the water quenching range has basically the same thickness from the middle to the two ends, and there is no fault.

[0044] Embodiment 2:

[0045] The difference between this embodiment and implementation 1 is that the groove mouth 2 in this embodiment includes a groove mouth outer shell 2-1 and a fire-resistant layer 2-2 coated on the inside of the groove mouth outer shell 2-1 and capable of withstanding high temperatures; a cooling water jacket 2-3 having the same shape as the groove mouth 2 and flowing cooling water inside is provided on the outer wall of the groove mouth outer shell 2-1, and a water inlet pipe 2-4 is provided on one side of the cooling water jacket 2-3 and a water outlet pipe 2-5 is provided on the other side.

[0046] Furthermore, the water inlet pipe 2-4 and the water outlet pipe 2-5 are respectively arranged in the middle of the top surface of the side wall of the cooling water jacket 2-3.

[0047] Furthermore, a control valve 2-6 is provided on the water inlet pipe 2-4.

[0048] The outer wall of the groove mouth is provided with a cooling water jacket with cooling water flowing inside. The slag flow at the groove mouth is cooled to a certain extent while ensuring sufficient fluidity. Combined with the refractory layer coated on the inner wall, it can prevent the slag flow from impacting and eroding the groove mouth, avoid the groove mouth becoming shorter due to erosion, affect the shape of the final outflowing slag flow and the landing point of the slag flow, prevent damage to the water outlet of the water spraying device, and prevent the slag flow from falling into the slag-water mixing tank, causing accidents.

Claims

1. A blast furnace slag discharge device, comprising a slag discharge groove (1) connected to a blast furnace slag outlet and a groove mouth (2) arranged at the end of the slag discharge groove (1), a water spray device (4) is arranged below the groove mouth (2), molten slag is discharged from the blast furnace slag outlet, flows down through the slag discharge groove (1) and the groove mouth (2), the slag flow (3) is quenched by the water flow sprayed by the water spray device (4), and then enters the slag-water mixing tank (5) below, the vertical height between the slag-water mixing tank (5) and the groove mouth (2) is 1 to 2 meters, characterized in that: The cross-sectional shape of the slag discharge groove (1) and the groove mouth (2) comprises a semicircular bottom and two side walls tangent to the semicircular bottom, and the two side walls are inclined outwards respectively; a diversion block (6) is fixedly arranged above the inside of the groove mouth (2) to disperse the slag flow (3) at the upper part of the groove mouth to the two sides; The angle between the two side walls of the slag discharge groove (1) and the groove mouth (2) and the outer horizontal plane is 45 to 60 degrees; The diverter block (6) comprises a top surface (6-1), a bottom surface (6-2), two side surfaces (6-3) and an end surface (6-4); the top surface (6-1) and the bottom surface (6-2) are planes composed of star-shaped lines containing only one sharp point, and the sharp point faces the flow direction of the molten slag; the end surface (6-4) is a trapezoidal plane, and the top edge length is 4 times the bottom edge length; the side surface (6-3) is set as a smooth surface that smoothly transitions from the top surface (6-1) to the bottom surface (6-2); The star line formula of the top surface (6-1) is: The star line formula of the bottom surface (6-2) is:

2. A blast furnace slag removal device according to claim 1, characterized in that: The diverter block (6) is fixed above the inside of the groove mouth (2) through a fixing plate, the top surface (6-1) of the diverter block (6) is fixed to the bottom surface of the fixing plate, and the two ends of the bottom surface of the fixing plate are fixed to the top of the groove mouth (2).

3. A blast furnace slag removal device according to claim 1, characterized in that: The trench mouth (2) comprises a trench mouth outer shell (2-1) and a fire-resistant layer (2-2) coated inside the trench mouth outer shell (2-1) and capable of withstanding high temperatures.

4. A blast furnace slag removal device according to claim 3, characterized in that: A cooling water jacket (2-3) having the same shape as the groove mouth (2) and having cooling water flowing inside is arranged on the outer side wall of the groove mouth shell (2-1); a water inlet pipe (2-4) is arranged on one side of the cooling water jacket (2-3) and a water outlet pipe (2-5) is arranged on the other side.

5. A blast furnace slag removal device according to claim 4, characterized in that: The water inlet pipe (2-4) and the water outlet pipe (2-5) are respectively arranged in the middle of the top surface of the side wall of the cooling water jacket (2-3).

6. A blast furnace slag removal device according to claim 4, characterized in that: The water inlet pipe (2-4) is provided with a control valve (2-6).

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