Drying kiln hot blast stove

Abstract

The utility model relates to the technical field of drying equipment, and discloses a drying kiln hot blast stove which is characterized in that a cylindrical hearth is arranged in a stove body, the central axis of the hearth extends along a first direction, a burner hole and an observation hole are formed in a first end wall of the stove body along the first direction, a hot air outlet is formed in a second end wall of the stove body, and the first direction is a horizontal direction; the fire barrier is in the shape of a quadrangular prism, the fire barrier is located in the hearth, and one edge of the fire barrier is right opposite to the burner hole. The hearth is designed to be cylindrical, the volume of the hearth is increased, and therefore the combustion area of flames is increased. The section of the hearth is changed from arch to round, flame combustion dead angles are effectively reduced, and the combustion efficiency is effectively improved; the cross section of the fire barrier is changed into the quadrangular prism from one vertical wall, one edge of the fire barrier is right opposite to the burner hole, and the quadrangular-prism-shaped fire barrier plays a role in shunting and guiding combustion flames, so that the resistance of hot air passing through the hot blast stove is reduced, the air passing amount is increased, and tempering of the observation hole is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of drying equipment, in particular to a drying kiln hot air furnace. Background Art

[0002] The drying kiln is a dryer for drying a large amount of materials. It is widely used in the ironmaking process of the steel industry. It consists of a combustion device, a hot air furnace, and a rotary kiln. The heat source of the drying kiln comes from the gas combustion device, which adopts a downstream heating method. When working, the material to be dried is slipped into the rotary kiln cylinder from the feed box and pushed to the rear end driven by the spiral scraper. Because the machine is placed at an angle, the material flows to the rear end under the action of gravity and rotation. At the same time, the material is repeatedly picked up by the scraper, brought to the upper end of the cylinder and then continuously scattered down, so that the material forms a uniform curtain in the cylinder, fully exchanging heat with the hot air flow in the cylinder. Due to the repeated scattering of the material, the moisture contained is gradually dried, thereby achieving the purpose of drying.

[0003] Under the action of the combustion-supporting fan, the mixture of coal gas and air burns in the furnace of the hot blast furnace to form a high-temperature flame. The inner wall of the hot blast furnace is made of refractory materials. The structure of the hot blast furnace is closely related to the combustion efficiency of coal gas and the drying capacity of the drying kiln.

[0004] The fire retaining wall of the drying kiln is located in the furnace of the hot blast furnace. Its function is to block the flame from moving forward and guide the hot air flow, prolong the combustion time of the gas, make the combustion more complete, and prevent the high temperature flame and smoke from directly flushing the inner wall of the dryer and burning the cylinder.

[0005] The internal shape of the traditional drying kiln hot air furnace is arched, the gas heating air capacity is low, and the fire retaining wall is a vertical wall. When the gas supply is increased and a large fire burns, the flame impacts the vertical wall of the fire retaining wall, which is blocked by the fire retaining wall and easily forms a flashback in the observation hole. In addition, the hot air resistance is large, the temperature drop from the hot air furnace into the rotary kiln drum is large, and the hot air replacement efficiency is low, which restricts the drying capacity of the drying kiln. Summary of the invention

[0006] The utility model aims to provide a drying kiln hot blast furnace to solve the problems of low gas heating air capacity of the arched drying kiln hot blast furnace in the above-mentioned background technology; the fire retaining wall of the vertical wall easily causes the observation hole to temper, the hot air resistance is large, and the hot air replacement efficiency is low.

[0007] In order to achieve the above purpose, the utility model provides the following technical solutions:

[0008] A drying kiln hot air furnace, comprising:

[0009] A furnace body, wherein the furnace body has a cylindrical furnace chamber, the central axis of the furnace chamber extends along a first direction, and along the first direction, a burner hole and an observation hole are provided on a first end wall of the furnace body, and a hot air outlet is provided on a second end wall of the furnace body, and the first direction is a horizontal direction;

[0010] The fire retaining wall is in the shape of a quadrangular prism, and is located in the furnace, with one of its edges facing the burner hole. Through this setting, the furnace is designed to be cylindrical, the furnace volume is increased, and thus the combustion area of ​​the flame is increased; the furnace cross section is changed from an arch to a circle, which effectively reduces the flame combustion dead angle and effectively improves the combustion efficiency; the fire retaining wall is changed from a vertical wall to a quadrangular prism, and one of its edges faces the burner hole. The quadrangular prism-shaped fire retaining wall plays a role in diverting and guiding the burning flame, reducing the resistance of hot air passing through the hot blast furnace, increasing the over-air volume, and avoiding flashback of the observation hole.

[0011] Furthermore, the burner hole and the hot air outlet are arranged opposite to each other along a first direction, and the burner hole and the observation hole are arranged up and down along a second direction, and the second direction is a vertical direction. Through this arrangement, the hot air can be guided to flow into the rotary kiln to the greatest extent, significantly improving the production capacity of the drying kiln.

[0012] Further, both ends of the fire baffle along the second direction are connected to the inner wall of the furnace, and the fire baffle has a first edge, a second edge, a third edge and a fourth edge, and there is a gap between the first edge, the second edge, the third edge and the fourth edge and the inner wall of the furnace, wherein the first edge of the fire baffle is arranged opposite to the burner hole, the second edge of the fire baffle is arranged opposite to the hot air outlet, and the plane where the first edge and the second edge are located is parallel to the plane where the first direction is located, and the plane where the third edge and the fourth edge of the fire baffle are located is perpendicular to the plane where the first direction is located. Through this arrangement, the prism surface of the quadrangular prism-shaped fire baffle adjacent to the first edge is symmetrically arranged along the first edge, and the two prism surfaces adjacent to the second edge are symmetrically arranged along the second edge, which can play a role in uniform diversion and guidance of the burning flame. When the hot air fluid moves, it is first diverted by the first edge, and the vortex formed will move along the prism surfaces on both sides of the second edge, assisting in entering the hot air outlet, and further reducing the resistance of air movement.

[0013] Furthermore, the distance between the fire baffle and the hot air outlet is one sixth of the furnace length, and the distance between the third edge and the fourth edge of the fire baffle is slightly larger than the hot air outlet diameter. Through the above improvement, the distance between the third edge and the fourth edge is reduced by 60 cm compared with the original, effectively reducing the resistance of hot air passing through the hot air furnace and increasing the air flow.

[0014] Furthermore, the furnace body is provided with a smoke exhaust hole connected to the furnace, the smoke exhaust hole is located at the top of the furnace body and between the fire baffle wall and the hot air outlet, and the smoke exhaust hole is connected to the dust removal equipment pipeline to discharge excess smoke and tail gas.

[0015] Furthermore, the furnace body is also provided with a temperature and pressure measuring hole connected to the furnace, and the temperature and pressure measuring hole is located between the fire baffle wall and the burner hole and is arranged close to the fire baffle wall. By arranging the temperature and pressure measuring hole, the temperature and pressure in the furnace can be detected at any time.

[0016] Furthermore, it also includes a connecting channel, which is used to connect the hot air outlet and the rotary kiln.

[0017] Furthermore, the fire retaining wall is formed by stacking high-alumina bricks.

[0018] Furthermore, the furnace wall of the furnace body is composed of andalusite brick layer, light clay layer and light refractory coating layer from inside to outside. The light refractory coating layer can be made of refractory spray coating such as ceramsite or perlite.

[0019] Furthermore, it also includes a gap filling body, which is used to fill the gaps in the furnace wall.

[0020] Furthermore, the gap filling body is a refractory fiber blanket.

[0021] The utility model has the following advantages over the prior art:

[0022] 1. The hot blast furnace of the drying kiln of the utility model is provided with a cylindrical furnace, and the internal cross-sectional shape of the original hot blast furnace is transformed from an arch to a circle, thereby increasing the furnace volume, reducing the dead angle of the furnace, and improving the ability of gas to heat the air; the shape of the fire baffle wall in the utility model is changed from a vertical wall to a prism, one of the edges of which is directly opposite to the burner hole, which can divert the hot air, reduce the resistance of the hot air passing through the hot blast furnace, increase the excess air volume, greatly improve the heat transfer efficiency, and then increase the temperature in the rotary kiln, reduce the temperature drop of the hot air from the hot blast furnace into the rotary kiln, high heating efficiency, and significantly improve the production capacity of the drying kiln; when a large fire is burning, the edges play a guiding and diverting role, and there is no flashback in the observation hole.

[0023] 2. The utility model provides a drying kiln hot air furnace with a cylindrical furnace, the first edge of the fire baffle wall is directly opposite to the burner hole, the second edge is directly opposite to the hot air outlet, and the prism surface adjacent to the first edge is symmetrically arranged along the first edge, and the two prism surfaces adjacent to the second edge are symmetrically arranged along the second edge. When the hot air fluid moves, it will first be diverted by the first edge, and the vortex formed will move along the prism surfaces on both sides of the second edge to assist in entering the hot air outlet, further reducing the resistance of air movement. The distance between the third edge and the fourth edge of the fire baffle wall along the width of the furnace is reduced by 60 cm compared with the original, which effectively reduces the resistance of hot air passing through the hot air furnace and increases the air flow. After inspection and through the above-mentioned transformation, the hot air temperature at the outlet of the rotary kiln has increased by 8-10°C compared with before the transformation, which greatly improves the drying capacity of the drying kiln. The dried laterite nickel ore increases by 15 tons per hour, and the production capacity is significantly increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a cross-sectional view of the front view of the hot air furnace of the drying kiln in the embodiment of the utility model;

[0025] Figure 2 It is a cross-sectional view of the side view of the hot air furnace of the drying kiln in the embodiment of the utility model;

[0026] Figure 3 It is a cross-sectional view of a top view of a hot air furnace of a drying kiln in an embodiment of the utility model;

[0027] In the figure: 1, furnace body; 2, furnace chamber; 3, burner hole; 4, observation hole; 5, hot air outlet; 6, fire retaining wall; 601, first edge; 602, second edge; 603, third edge; 604, fourth edge; 7, smoke exhaust hole; 8, temperature and pressure measuring holes; 9, connecting channel; 10, andalusite brick layer; 11, lightweight clay layer; 12, lightweight refractory coating layer; 13, gap filling body; X, first direction. DETAILED DESCRIPTION

[0028] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0029] It should be noted that, in the description of the present invention, the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc. indicating directions or positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0030] In addition, it should be understood that for the convenience of description, the sizes of various components shown in the drawings are not drawn according to the actual proportional relationship.

[0031] It should be noted that like reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined or described in one drawing, it will not need to be further discussed and described in detail in the description of the subsequent drawings.

[0032] Example:

[0033] like Figures 1 to 3 As shown, a drying kiln hot air furnace comprises: a furnace body 1, wherein the furnace body 1 has a cylindrical furnace chamber 2 inside, and the central axis of the furnace chamber 2 is along a first direction (such as Figure 1 The furnace body 1 extends in the first direction (in the X direction shown in the figure), and along the first direction, a burner hole 3 and an observation hole 4 are provided on the first end wall of the furnace body 1, and a hot air outlet 5 is provided on the second end wall of the furnace body 1. The first direction is the horizontal direction; the burner hole 3 is used to introduce hot air flame, the observation hole 4 is used to observe the flame situation in the furnace chamber 2, and the hot air outlet 5 is used to guide the high-temperature hot air into the rotary kiln.

[0034] The fire retaining wall 6 is in the shape of a quadrangular prism, and is located in the furnace 2, and one of the edges of the fire retaining wall 6 is arranged opposite to the burner hole 3. Through this arrangement, the furnace is designed to be cylindrical, the furnace volume is increased, and thus the combustion area of ​​the flame is increased; the cross section of the furnace is changed from an arch to a circle, which effectively reduces the flame combustion dead angle and effectively improves the combustion efficiency; the fire retaining wall is changed from a vertical wall to a quadrangular prism, and one of the edges of the fire retaining wall is opposite to the burner hole. The quadrangular prism-shaped fire retaining wall plays a role in diverting and guiding the burning flame, reducing the resistance of the hot air passing through the hot blast furnace, and increasing the amount of over-air, because the edges play a role in guiding and diverting, and flashback is avoided in the observation hole.

[0035] like Figure 1 and Figure 3As shown, in this embodiment, the burner hole 3 and the hot air outlet 5 of the hot air furnace of the drying kiln are arranged opposite to each other along the first direction. The high-temperature flame enters the hot air furnace through the burner hole 3, and after being guided and diverted by the first edge 601, it flows along the prism surface on both sides of the second edge 602, and then enters the rotary kiln through the hot air outlet 5 under the guidance of the second edge 602. The burner hole 3 and the observation hole 4 are arranged up and down along the second direction, wherein the second direction is the vertical direction. Both ends of the fire baffle 6 along the second direction are connected to the inner wall of the furnace 2, and the fire baffle 6 has a first edge 601, a second edge 602, a third edge 603 and a fourth edge 604, and there is a gap between the first edge 301, the second edge 602, the third edge 603 and the fourth edge 604 and the inner wall of the furnace 2, and this gap is used to pass the high-temperature flame airflow. Among them, the first edge 601 of the fire baffle 6 is arranged opposite to the burner hole 3, the second edge 602 of the fire baffle 6 is arranged opposite to the hot air outlet 5, and the plane where the first edge 601 and the second edge 602 are located is parallel to the plane where the first direction is located, and the plane where the third edge 603 and the fourth edge 604 of the fire baffle 6 are located is perpendicular to the plane where the first direction is located. Through this arrangement, the first edge is opposite to the second edge, and the first edge is opposite to the burner hole, and the second edge is opposite to the hot air outlet. The prism surface adjacent to the first edge 601 in the quadrangular prism-shaped fire baffle 6 is symmetrically arranged along the first edge, and the two prism surfaces adjacent to the second edge 602 are symmetrically arranged along the second edge. When the hot air fluid moves, it is first diverted by the first edge, and the vortex formed will move along the prism surfaces on both sides of the second edge, assisting in entering the hot air outlet, and further reducing the resistance of air movement. If the two prism faces adjacent to the second edge are not symmetrically arranged along the second edge or the second edge is not facing the hot air outlet, the high-temperature air will hit the surrounding walls before entering the hot air outlet, increasing the loss of hot air flow and reducing the amount of hot air entering the rotary kiln. After the above transformation, the temperature of the hot air outlet 5 of the hot air furnace of the drying kiln increased by 8-10°C, and the drying capacity of the drying kiln increased from 110 tons / hour to 125 tons / hour, and the drying capacity increased by 13.6%.

[0036] In this embodiment, the distance between the fire baffle 6 and the hot air outlet 5 is one sixth of the length of the furnace 2, and the distance between the third edge 603 and the fourth edge 604 of the fire baffle 6 is slightly larger than the diameter of the hot air outlet. The installation position of the fire baffle 6 is determined through multiple experiments, and the distance between the third edge 603 and the fourth edge 604 is reduced by 60 cm compared with the original, which effectively reduces the resistance of hot air passing through the hot air furnace and increases the air flow.

[0037] The furnace body 1 is also provided with a smoke exhaust hole 7 connected to the furnace 2. The smoke exhaust hole 7 is located at the top of the furnace body 1 and between the fire baffle 6 and the hot air outlet 5. The smoke exhaust hole 7 is connected to the dust removal equipment pipeline to discharge excess smoke and tail gas. The furnace body 1 is also provided with a temperature and pressure measuring hole 8 connected to the furnace 2. The temperature and pressure measuring hole 8 is located between the fire baffle 6 and the burner hole 3 and is arranged close to the fire baffle 6. By setting the temperature and pressure measuring hole 8, the temperature and pressure in the furnace 2 can be detected at any time. The hot blast furnace is also provided with a connecting channel 9, which is used to connect the hot air outlet 5 with the rotary kiln.

[0038] The fire retaining wall 6 in this embodiment is made of stacked high-alumina bricks, which have a high fire resistance and effectively improve the service life of the fire retaining wall 6. The furnace wall of the furnace body 1 is composed of andalusite brick layer 10, light clay layer 11 and light refractory coating layer 12 from inside to outside. The light refractory coating layer 12 can be made of refractory spray coating such as ceramsite or perlite. It also includes a gap filling body 13, which is used to fill the gaps in the furnace wall. Among them, the gap filling body 13 is a refractory fiber blanket.

[0039] The hot air furnace of the drying kiln in this embodiment adopts a cylindrical furnace chamber, which increases the furnace chamber volume, reduces dead corners in the furnace, increases the flame combustion area, and thus improves the ability of the flame to heat the air. The use of a prismatic retaining wall reduces the resistance of the rectangular retaining wall to blocking the transfer of hot air, and can also meet the functions of extending the flame burning time and guiding the flow direction of hot air, avoiding backfire in the observation hole, and further improving the ability to guide the flow direction of hot air, thereby solving the problem of low heating efficiency of the existing hot air furnace of the drying kiln and restricting the production capacity of the drying kiln.

[0040] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A drying kiln hot air furnace, characterized in that: include: A furnace body, wherein the furnace body has a cylindrical furnace chamber, the central axis of the furnace chamber extends along a first direction, and along the first direction, a burner hole and an observation hole are provided on a first end wall of the furnace body, and a hot air outlet is provided on a second end wall of the furnace body, and the first direction is a horizontal direction; The fire retaining wall is in the shape of a quadrangular prism and is located in the furnace. One of the edges of the fire retaining wall is arranged opposite to the burner hole.

2. The drying kiln hot air furnace according to claim 1, characterized in that: The burner hole and the hot air outlet are arranged opposite to each other along a first direction, and the burner hole and the observation hole are arranged up and down along a second direction, and the second direction is a vertical direction.

3. The drying kiln hot air furnace according to claim 2, characterized in that: Both ends of the fire baffle wall along the second direction are connected to the inner wall of the furnace, and the fire baffle wall has a first edge, a second edge, a third edge and a fourth edge, and there is a gap between the first edge, the second edge, the third edge and the fourth edge and the inner wall of the furnace, wherein the first edge of the fire baffle wall is arranged opposite to the burner hole, the second edge of the fire baffle wall is arranged opposite to the hot air outlet, and the plane where the first edge and the second edge are located is parallel to the plane where the first direction is located, and the plane where the third edge and the fourth edge of the fire baffle wall are located is perpendicular to the plane where the first direction is located.

4. The drying kiln hot air furnace according to claim 3, characterized in that: The distance between the fire baffle wall and the hot air outlet is one sixth of the length of the furnace, and the distance between the third edge and the fourth edge of the fire baffle wall is slightly larger than the diameter of the hot air outlet.

5. The drying kiln hot air furnace according to claim 1, characterized in that: A smoke exhaust hole connected to the furnace is provided on the top of the furnace body, and the smoke exhaust hole furnace is located between the fire retaining wall and the hot air outlet.

6. The drying kiln hot air furnace according to claim 1, characterized in that: The furnace body is also provided with temperature and pressure measuring holes communicated with the furnace, and the temperature and pressure measuring holes are located between the fire retaining wall and the burner hole and are arranged close to the fire retaining wall.

7. The drying kiln hot air furnace according to claim 1, characterized in that: It also includes a connecting channel, which is used to connect the hot air outlet and the rotary kiln.

8. The drying kiln hot air furnace according to claim 1, characterized in that: The fire retaining wall is formed by stacking high-alumina bricks.

9. The drying kiln hot air furnace according to claim 1, characterized in that: The furnace wall of the furnace body is composed of andalusite brick layer, light clay layer and light refractory coating layer from inside to outside.

10. The drying kiln hot air furnace according to claim 9, characterized in that: Also included is a gap filling body, which is used to fill the gaps in the furnace wall.

Images