KR101257062B1 - Limestone calcination apparatus and controling method thereof - Google Patents

Abstract

Limestone calcining apparatus and control method thereof are disclosed. According to an embodiment of the present invention, a calcining furnace in which limestone is heated and calcined; Blower to blow outside air; A preheater connected to the blower, disposed on an outer surface of the firing furnace, and preheating air supplied from the blower; An exhaust fan connected to the preheater to blow air preheated by the preheater; And a burner connected to the exhaust fan to supply preheated air to the firing furnace.

Description

Limestone firing apparatus and its control method {LIMESTONE CALCINATION APPARATUS AND CONTROLING METHOD THEREOF}

The present invention relates to a limestone calcining apparatus that can recover the thermal energy of a kiln and use it in the calcining process of limestone, and a control method thereof.

In general, the limestone calcining process of an ironworks is a process of manufacturing quicklime by heating limestone. Quicklime can be used in steelmaking and sintering processes. In the steelmaking process, it may be used to form slag or to dephosphorize and desulfurize phosphorus and sulfur contained in molten iron. The lime kiln may be applied to a rotary kiln for heating the limestone as the kiln is rotated.

Republic of Korea Publication No. 10-2005-0045208 (published May 17, 2005) discloses a method for producing quicklime using pulverized coal. In the method of preparing quicklime, dust generated during the manufacture and cooling of coke is collected in a dust collector and used as a raw material of a kiln. Thus, it is possible to significantly reduce the pollutants in the gas. As the air at room temperature is supplied through the burner, the kiln is burned to heat the kiln to a high temperature. Some heat energy generated in the kiln is released to the outside.

Embodiments of the present invention, to provide a limestone calcining apparatus and a control method thereof that can be used in the calcining process of limestone by recovering the thermal energy of the kiln.

According to an aspect of the present invention, a calcining furnace in which limestone is heated and calcined; Blower to blow outside air; A preheater connected to the blower, disposed on an outer surface of the firing furnace, and preheating air supplied from the blower; An exhaust fan connected to the preheater to blow air preheated by the preheater; And a burner connected to the exhaust fan to supply preheated air to the firing furnace.

The preheating device may include: a first preheating unit contacting an outer surface of the firing furnace to form a first preheating chamber to preheat air supplied from the blower; A second preheating part partitioned from the first preheating part to form a second preheating chamber; And a flow path opening and closing device connected to the first preheating unit and the second preheating unit to communicate or close the first preheating chamber and the second preheating chamber.

The apparatus may further include a moving device which moves the second preheater to move above the first preheater or to one side of the first preheater.

The moving device may move the second preheater along the circumferential direction of the firing furnace.

The first preheating unit, the first insulating member is installed to be spaced apart from the outer surface of the firing furnace; And a first sealing member coupled to both sides of the first insulating member and in contact with an outer surface of the firing furnace.

The second preheating unit may include: a second heat insulating member disposed to overlap the first heat insulating member on an upper side of the first heat insulating member; And a second sealing member coupled to one side or both sides of the second insulating member and in contact with an outer surface of the firing furnace.

The second preheater may further include a movement sensor to detect a movement range of the mobile device.

The first preheating unit may further include a temperature sensor to measure the outside surface temperature of the kiln to supply or block the air of the first preheating unit to the second preheating unit.

When the temperature detected by the temperature sensor is more than 400 ℃ less than 430 ℃ The moving device moves the second preheating unit to communicate with the second preheat chamber, the temperature detected by the temperature sensor is more than 430 ℃ 480 ℃ The moving device may move the second preheating unit to block the second preheating chamber and the outside.

The preheater may be arranged on the burner side of the kiln.

According to another embodiment of the present invention, a step of supplying air to the preheater by operating a blower; Allowing the air supplied to the preheater to be preheated in thermal contact with the outer surface of the kiln; And supplying air preheated in the preheater to the burner by an exhaust fan.

In the preheating of the air, the air is supplied only to the first preheating chamber when the outer surface temperature of the firing furnace is 400 ° C. or higher and less than 430 ° C., and the first preheating chamber when the outer surface temperature of the firing furnace is 430 ° C. or higher and 480 ° C. or lower. And supply air to the second preheating chamber.

When the air is supplied only to the first preheating chamber, the moving device moves the second preheating unit to communicate with the outside of the second preheating chamber, and when the air is supplied to the second preheating chamber, the moving device preheats the second preheating chamber. The part may be moved to block the second preheating chamber and the outside.

According to embodiments of the present invention, there is an effect that can be used in the calcining process of limestone by recovering the thermal energy of the kiln.

1 is a block diagram showing a limestone firing apparatus in an embodiment of the present invention.
FIG. 2 is a configuration diagram illustrating the firing furnace and the preheating apparatus of FIG. 1.
3 is a block diagram illustrating the preheating apparatus of FIG. 2.
4 is a configuration diagram illustrating a state in which the second preheater of the preheater of FIG. 1 is opened.
Figure 5 is a flow chart illustrating a control method of the locker kiln according to the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. In the following description of the present invention, if it is determined that the detailed description of the related known technology may obscure the gist of the present invention, the detailed description thereof will be omitted.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram showing a limestone firing apparatus in an embodiment of the present invention.

FIG. 2 is a configuration diagram illustrating the firing furnace and the preheating apparatus of FIG. 1.

1 and 2, the limestone calcination apparatus may include a calcination furnace 110, a blower 121, a preheater 130, an exhaust fan 125, and a burner 107.

Preheating hopper 101 may be installed on one side of the kiln 110. The preheating hopper 101 is charged with a particle size and washed limestone by a screen (not shown). The limestone whose particle size is selected is preheated in the preheating hopper 101. Limestone may be preheated by the gas discharged from the kiln 110 to the preheating hopper 101 side. In addition, a preheater (not shown) may be installed in the preheating hopper 101 to preheat the limestone.

The kiln 110 may be formed in a cylindrical shape. The kiln 110 may be rotatably installed in a slightly inclined state. As the kiln 110 is rotated in an inclined state, limestone may be slowly transported while being mixed and heated.

The burner 107 may be installed on the opposite side of the preheating hopper 101 of the firing furnace 110. The exhaust pipe 113 and the coke gas supply pipe 115 may be connected to the burner 107. The burner 107 provides flame to the kiln 110 while burning the coke gas and air. In the kiln 110, limestone is heated to a temperature of approximately 1000 to 1250 ° C by the flame to sinter the limestone.

The cooler 105 may be installed below the burner 107 of the firing furnace 110 to cool the calcined quicklime. The cooler 105 may cool the quicklime discharged from the kiln 110 to about 70 ° C. The quicklime cooled in the cooler 105 is recovered as a quicklime product.

The preheating device 130 may be installed on the outer surface of the kiln 110. The preheater 130 may be disposed on the burner 107 side of the firing furnace 110. Since the kiln 110 is heated by the burner 107, the burner 107 side of the kiln 110 becomes relatively high temperature compared with the preheating hopper 101 side. The preheater 130 may allow the air to be preheated at a relatively high temperature in the kiln 110. Accordingly, the preheater 130 may improve the fire power of the burner 107 by supplying hot air to the burner 107.

The preheater 130 is connected to the blower 121 by the air supply pipe 111. The preheater 130 may allow the air supplied from the blower 121 to be preheated by contacting the outer surface of the firing furnace 110.

The preheater 130 and the burner 107 may be connected by the exhaust pipe 113. In the exhaust pipe 113, an exhaust fan 125 may be installed to blow air connected to the preheater 130 to the burner 107. The burner 107 may be connected to the coke gas supply pipe 115. Accordingly, the burner 107 supplies the coke gas and the preheated air to the firing furnace 110 to heat the firing furnace 110 to a high temperature.

The preheater 130 may include a first preheater 140, a second preheater 150, and a channel opening and closing device 160. The preheater 130 may be installed not to rotate together with the kiln 110 when the kiln 110 is rotated.

The first preheater 140 is in contact with the outer surface of the firing furnace 110, the second preheater 150 may be installed reciprocally on the outer side of the first preheater 140.

The first preheating unit 140 may be installed to be in contact with the outer surface of the firing furnace 110 to form the first preheating chamber 145 to preheat the air supplied from the blower 121. The first preheater 140 is installed so as not to rotate together with the firing furnace 110.

The first preheating unit 140 is coupled to both sides of the first heat insulating member 141 and the first heat insulating member 141 which is installed to be spaced apart from the outer surface of the firing furnace 110, and contacts the outer surface of the firing furnace 110. It may include a first sealing member 143. In this case, the first preheating chamber 145 may be defined as a space surrounded by an outer surface of the first insulation member 141, the first sealing member 143, and the firing furnace 110.

When there are two first heat insulating members 141, the first preheating unit 140 may include two first preheating chambers 145. When there is one first heat insulating member 141, the first preheating unit 140 may include one first preheating chamber 145.

The first insulation member 141 may be formed of a synthetic resin or ceramic material having low thermal conductivity. The first insulation member 141 may be formed in a plate shape rounded to correspond to the arc of the outer circumferential surface of the firing furnace 110.

The first sealing member 143 may be formed of a material having excellent heat resistance so that the first sealing member 143 is not denatured or damaged by the surface temperature of the firing furnace 110 when it is in contact with the firing furnace 110. The first sealing member 143 allows rotation of the firing furnace 110 but shields the first preheating chamber 145 from the outside. The first sealing member 143 is formed of an elastic material to prevent the leakage of air when the firing furnace is rotated.

The second preheater 150 may be partitioned from the first preheater 140 to form a second preheat chamber 155. The second preheater 150 is partitioned from the first preheating chamber 145 of the first preheater 140. The second preheating unit 150 is installed so as not to rotate together with the firing furnace 110.

The second preheating unit 150 is coupled to the second heat insulating member 151 and one side of the second heat insulating member 151 installed to overlap the first heat insulating member 141 on the upper side of the first heat insulating member 141. And a second sealing member 153 contacting the outer surface of the firing furnace 110. In this case, the other side of the second insulation member 151 may be in close contact with the outer surface of the first insulation member 141 to prevent the air from leaking from the second preheating chamber 155. In addition, the second sealing member 153 may be formed of an elastic material to prevent leakage of air when the firing furnace is rotated.

The second preheating unit 150 is coupled to both sides of the second insulating member 151 and the second insulating member 151 which are installed to overlap the first insulating member 141 on the upper side of the first insulating member 141. And a second sealing member 153 contacting the outer surface of the firing furnace 110 and the outer surface of the first insulation member. In this case, the second sealing member 153 may prevent the air from leaking from the second preheating chamber 155.

When the first preheating unit 140 includes two first preheating chambers 145, the second preheating unit 150 may include two second preheating chambers 155. In this case, each second insulation member 151 may be installed to overlap with the corresponding first insulation member 141, respectively.

When the first heat insulation unit includes one first preheat chamber 145, the second preheat unit 150 may include one second preheat chamber 155.

The second insulation member 151 may be formed of a synthetic resin or ceramic material having low thermal conductivity. The second insulation member 151 may be rounded to correspond to the arc of the outer circumferential surface of the firing furnace 110.

The second sealing member 153 may be formed of a material having excellent heat resistance so that the second sealing member 153 is not denatured or damaged by the surface temperature of the kiln 110 when it is in contact with the kiln 110. The second sealing member 153 allows rotation of the firing furnace 110 but shields the second preheating chamber 155 from the outside.

3, the flow path opening and closing device 160 is connected to the first preheating unit 140 and the second preheating unit 150 to communicate the first preheating chamber 145 and the second preheating chamber 155. Close it. The flow path opening and closing device 160 is connected to the first preheating chamber 145 and the second preheating chamber 155, and the connection pipe 161 is installed at the connection pipe 161 to open and close the flow path of the connection pipe 161. It may include an on-off valve 163.

The preheating device 130 may further include a moving device 170 which moves the second preheating part 150 to close or open the second preheating chamber 155 with the outside. The moving device 170 may move the second preheater 150 along the circumferential direction of the firing furnace 110.

The moving device 170 may move the second preheater 150 along the circumferential direction of the firing furnace 110. Of course, the moving device 170 may move the second preheater 150 away from the surface of the firing furnace 110.

The moving device 170 includes a rod 171 connected to the second insulating member 151 of the second preheater 150, and a piston coupled to the rod 171 to reciprocate the rod 171 by hydraulic pressure. 173 and a hydraulic pressure supply unit 175 for supplying and discharging hydraulic pressure to the piston 173.

In addition, the moving device 170 may include a belt in which pulleys are installed at both ends and the second insulating member 151 is connected, and a motor for rotating the pulley to move the belt. The moving device 170 may move the second insulation member 151 as the belt is driven by the motor.

In addition to the above-described embodiment, the moving device 170 may be applied in various forms as long as the second preheater 150 is moved.

The second preheater 150 may further include a movement sensor 181 to detect the movement range of the movement device 170. As the movement detecting sensor 181, a limit switch or a proximity sensor may be applied. The movement detection sensor 181 transmits a signal to the controller 190 that the second preheater 150 is completely closed when the movement sensor 181 approaches or contacts. In addition, the movement detection sensor 181 may transmit a signal to the controller 190 that the second preheater 150 is completely opened when the distance is far from each other.

The first preheater 140 further includes a temperature sensor 183 to measure the outside surface temperature of the firing furnace 110 to supply or block the air of the first preheater 140 to the second preheater 150. Can be. The temperature sensor 183 measures the surface temperature of the kiln 110 and transmits it to the controller 190. The temperature sensor 183 may be a contact type temperature sensor 183 in contact with the surface of the firing furnace 110 or a non-contact temperature sensor 183 that does not contact the surface of the firing furnace 110.

When the average temperature detected by the temperature sensor 183 is 400 ° C. or more and less than 430 ° C., the controller 190 drives the moving device 170 to move the second preheater 150 to move the second preheat chamber 155. Communicate with the outside world. In this case, the controller 190 may close the flow path of the connection pipe 161 by controlling the opening and closing valve 163 to block the air of the first preheating chamber 145 to flow into the second preheating chamber 155. When the kiln 110 is not sufficiently heated, air is preheated only in the first preheating chamber 145 to reduce the thermal contact between the air and the kiln 110. Therefore, the quality of the quicklime can be prevented from being lowered due to the temperature decrease of the firing furnace 110.

When the average temperature detected by the temperature sensor 183 is 430 ° C. or more and less than 480 ° C., the controller 190 drives the moving device 170 to move the second preheater 150 to move the second preheat chamber 155. Can be cut off from the outside. At this time, the controller 190 may control the on-off valve 163 to open the flow path of the connecting pipe 161 to allow the air of the first preheating chamber 145 to flow into the second preheating chamber 155. When the kiln 110 is sufficiently heated, the air may be preheated in the first preheat chamber 145 and the second preheat chamber 155. Therefore, when the kiln 110 is sufficiently heated, a relatively large amount of air may be preheated and then supplied to the burner 107.

3 is a block diagram showing a preheater.

Referring to FIG. 3, the controller 190 includes a temperature sensor 183, a flow path opening and closing device 160, a moving device 170, a movement detecting sensor 181, a blower 121, and an exhaust fan 125. Or wirelessly connected. The controller 190 moves the second preheater 150 according to the temperature detected by the temperature sensor 183 and controls the flow path opening and closing device 160 to be opened or closed. Therefore, when the kiln 110 is not sufficiently heated, air may be preheated only to the first preheater 140 to be supplied to the burner 107. When the kiln 110 is sufficiently heated, air may be preheated in the first preheater 140 and the second preheater 150 to be supplied to the burner 107.

It will be described with respect to the control method of the limestone firing apparatus according to the present invention configured as described above.

2 is a block diagram showing a state in which the second preheater of the preheater is closed, FIG. 4 is a block diagram showing a state of the second preheater of the preheater, and FIG. 5 is a locker kiln according to the present invention. Is a flow chart showing a control method of a.

2, 4 and 5, the preheated limestone is supplied to the kiln 110, the flame is injected from the burner 107 is heated limestone. The kiln 110 is rotated so that the limestone is moved to the burner 107 side.

The blower 121 and the exhaust fan 125 are operated (S11). As the blower 121 is operated, external air is supplied to the preheater 130.

The temperature sensor 183 measures the outer surface temperature of the kiln 110 and transmits it to the controller 190. The controller 190 may monitor the outer surface temperature of the kiln 110 in real time (S12). The controller 190 receives the outside surface temperature of the kiln 110 from the temperature sensor 183 and calculates an average value.

The controller 190 determines whether the average value of the outer surface temperature of the firing furnace 110 reaches the preheating range (S13). Here, the firing furnace 110 maintains the temperature range of the surface temperature is 400 ℃ or more and less than 430 ℃ when the temperature is relatively low. The kiln 110 maintains a temperature range of 430 ° C. to 480 ° C. when the surface temperature is relatively high. Therefore, the preheating range may be defined as a temperature range of the outer surface temperature of the firing furnace 110 is 430 ° C or more and 480 ° C or less.

 If the average value of the surface temperature of the kiln 110 is less than the preheating range, the control unit 190 performs the first stage preheating (S14). One stage preheating is performed when the outer surface temperature of the kiln 110 is about 400 degreeC or more and less than 430 degreeC. The first stage preheating is a preheating method in which air is supplied only to the first preheater 140 and no air is supplied to the second preheater 150.

Referring to FIG. 4, when the first stage preheating is performed, the second preheater 150 is moved to open the second preheating chamber 155 (S15). That is, as the moving device 170 is driven, the second insulating member 151 is moved to overlap the upper side of the first insulating member 141. In this case, the second preheating chamber 155 may be opened to the outside.

The movement detecting sensor 181 detects whether the second insulation member 151 is sufficiently opened (S16). When the controller 190 receives a signal indicating that the second insulating member 151 is sufficiently open from the movement sensor 181, the controller 190 stops driving of the moving device 170 to stop the opening operation of the second insulating member 151. (S17). At this time, the second insulation member 151 is no longer moved.

Since the control unit 190 operates the on / off valve 163 to close the flow path of the connection pipe 161, air is supplied only to the first preheating chamber 145 to be in thermal contact with the surface of the firing furnace 110 (S18). Therefore, when the temperature of the kiln 110 is relatively low, since a relatively small amount of air is heat-exchanged with the kiln 110, relatively little heat energy required for calcining limestone in the kiln 110 is taken away. As a result, when the kiln 110 is relatively low temperature, it is possible to prevent the temperature of the kiln 110 from being lowered to improve the calcination quality of the limestone.

The temperature sensor 183 delivers the surface temperature of the kiln 110 to the controller 190 in real time while the one-stage preheating method is executed. If it is determined that the surface temperature of the kiln 110 is in the preheating temperature range, the controller 190 may control to perform the two-stage preheating as follows while the first stage preheating is performed.

The air preheated in the first preheat chamber 145 is supplied to the burner 107 (S26). The burner 107 injects preheated air and coke gas into the kiln 110 to form a flame.

On the other hand, when the average value of the surface temperature of the kiln 110 reaches the preheating range, the control unit 190 performs two-stage preheating (S21). Two stage preheating is performed when the outer surface temperature of the kiln 110 is about 430 degreeC or more and 480 degrees C or less. The two-stage preheating is a preheating method for supplying air to both the first preheater 140 and the second preheater 150.

Referring to FIG. 2, when the second stage preheating is performed, the second preheater 150 is moved to close the second preheating chamber 155 (S22). That is, by the driving device 170 is driven, the second insulation member 151 is moved so as to almost deviate from the upper side of the first insulation member 141. In this case, the second preheating chamber 155 may be closed from the outside.

The movement detection sensor 181 detects whether the second insulation member 151 is moved to be completely closed (S23). When the controller 190 receives a signal indicating that the second insulation member 151 is sufficiently closed by the movement sensor 181, the controller 190 stops driving of the mobile device 170 to stop the closing operation of the second insulation member 151. (S24). At this time, the second insulation member 151 is no longer moved.

Since the control unit 190 operates the on / off valve 163 to open the flow path of the connecting pipe 161, the air of the first preheating chamber 145 is supplied to the second preheating chamber 155, and thus the surface of the firing furnace 110. It is in thermal contact with (S25). Therefore, when the temperature of the kiln 110 is relatively high, a relatively large amount of air may be heat-exchanged with the kiln 110.

The air preheated in the first preheat chamber 145 and the second preheat chamber 155 is supplied to the burner 107 (S26). Since burner 107 is supplied with air of a relatively high temperature, the flame performance of burner 107 is increased. Therefore, the baking quality of limestone can be improved.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit of the invention as set forth in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

101: preheat hopper 110: firing furnace
107: burner 121: blowing fan
125: exhaust fan 130: preheater
140: first preheating unit 141: first heat insulating member
143: first sealing member 145: first preheating chamber
150: second preheating unit 151: second heat insulating member
153: second sealing member 155: second preheating chamber
160: euro opening and closing device 170: moving device

Claims (13)

A kiln in which limestone is heated and fired;
Blower to blow outside air;
A preheater connected to the blower, disposed on an outer surface of the firing furnace, and preheating air supplied from the blower;
An exhaust fan connected to the preheater to blow air preheated by the preheater; And
A burner connected to the exhaust fan and supplying preheated air to a firing furnace,
The preheater,
A first preheating part contacting an outer surface of the kiln to form a first preheating chamber to preheat air supplied from the blower;
A second preheating part partitioned from the first preheating part to form a second preheating chamber; And
And a flow channel opening and closing device connected to the first preheating unit and the second preheating unit to communicate or close the first preheating chamber and the second preheating chamber.
delete The method of claim 1,
Limestone sintering device further comprises a moving device for moving the second preheater to the upper side of the first preheater or one side of the first preheater.
The method of claim 3, wherein
The moving device is a limestone firing apparatus, characterized in that for moving the second preheating unit in the circumferential direction of the firing furnace.
The method according to any one of claims 1, 3 and 4,
The first preheating unit,
A first insulating member spaced apart from an outer surface of the firing furnace; And
A limestone firing apparatus coupled to both sides of the first heat insulating member, the first sealing member in contact with the outer surface of the firing furnace.
The method of claim 5, wherein
The second preheating unit,
A second heat insulating member installed to overlap the first heat insulating member on an upper side of the first heat insulating member; And
Limestone sintering apparatus is coupled to one side or both sides of the second heat insulating member, the second sealing member for sealing both sides of the first heat insulating member.
The method according to claim 3 or 4,
The second preheating unit is limestone firing apparatus further comprises a movement detecting sensor to detect the movement range of the moving device.
The method according to claim 3 or 4,
The first preheating unit is limestone calcining apparatus further comprises a temperature sensor to measure the outside surface temperature of the firing furnace to supply or block the air of the first preheating unit to the second preheating unit.
The method of claim 8,
When the temperature detected by the temperature sensor is more than 400 ℃ less than 430 ℃ the moving device moves the second preheating unit to communicate the second preheating chamber with the outside,
When the temperature detected by the temperature sensor is more than 430 ℃ 480 ℃ The limestone calcining apparatus, characterized in that for moving the second preheating unit to block the second preheating chamber and the outside.
The method according to any one of claims 1, 3 and 4,
The preheater is limestone firing apparatus, characterized in that disposed on the burner side of the kiln.
Operating a blower to supply air to the preheater; And
Allowing the air supplied to the preheater to be preheated in thermal contact with the outer surface of the kiln; And
Supplying air preheated in the preheater to the burner by an exhaust fan,
In the step of preheating the air,
When the outer surface temperature of the kiln is 400 ° C. or more and less than 430 ° C., air is supplied only to the first preheating chamber. Control method of limestone firing apparatus, characterized in that the supply.
delete The method of claim 11,
When air is supplied only to the first preheating chamber, the moving device moves the second preheating unit to communicate the second preheating chamber with the outside,
When air is supplied to the second preheating chamber, the moving device moves the second preheating unit to cut off the second preheating chamber and the outside.

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