Temperature-controlled roasting rotary kiln, building method and roasting process

Abstract

The invention relates to a temperature-controlled roasting rotary kiln, a building method and a roasting process, and belongs to the technical field of mine mining. Comprising a furnace body, a heat preservation layer, an air blowing system, a combustion chamber, a combustor, a feeder, a stock bin and a discharging port, the heat preservation layer is arranged on the inner wall of the furnace body, the combustion chamber is arranged on the outer wall of the furnace body, the combustor is assembled in the combustion chamber, the combustor is communicated with an external combustion gas source, and the combustion chamber is communicated with the interior of the furnace body through a heat transfer pipe arranged in the furnace body. The device is reasonable in design structure and process, the service life of the furnace lining is prolonged through the use of the metal lining, and the occurrence of lining adhesion is reduced. Through the application of the temperature control technology, a local high-temperature area in the kiln is eliminated, and therefore the ring forming phenomenon is avoided. And full contact with mineral powder in the kiln is ensured, and the reduction reaction efficiency is improved. Constant high temperature is kept in the kiln, and roasting efficiency and roasting quality are improved.

Description

Technical Field

[0001] The invention relates to a temperature-controlled roasting rotary kiln, a masonry method and a roasting process, and belongs to the technical field of mine mining. Background Art

[0002] The rotary kiln is an important equipment for magnetized reduction roasting of limonite. During roasting, the bottom is the combustion end, and the burner extends into the rotary kiln for combustion and heat. Powdered iron ore is added to the rotary kiln from the upper port of the rotary kiln. During the rotation of the rotary kiln, the iron ore continuously flows from the feeding end to the discharging end. During the flow, it exchanges heat with the high-temperature flue gas coming from the counterflow to increase its temperature. It contacts with the reducing coal powder sprayed from the outlet of the rotary kiln or the carbon monoxide gas formed by incomplete combustion, and the iron ore is reduced, so that the iron ore can be roasted better. Due to the high temperature at the combustion end, the high temperature causes the ore powder to liquefy, and after contacting the kiln wall, it will adhere to the kiln wall, and finally cause the rotary kiln to form rings. Because it is heated at one end, it relies on the transmission of heat and reducing atmosphere to gradually contact with the ore powder, so that the ore powder can be roasted, which often leads to unstable sintering temperature and weak reducing atmosphere, affecting the roasting quality. Preventing and slowing down the ringing phenomenon is a technical link that needs to be solved in the magnetized roasting process. In industrial practice, by adjusting the flame, adjusting the process parameters, and selecting refractory materials, the formed rings can be periodically shed or the occurrence of rings can be slowed down, but it cannot fundamentally solve the ring phenomenon. For this reason, it is necessary to design a temperature-controlled roasting rotary kiln and a sintering process that can solve the ring phenomenon caused by local overheating, ensure that the reaction temperature in the kiln is controllable and uniform, the reducing atmosphere is fully stable, the ore powder is fully in contact with the reducing gas, and the magnetization reduction efficiency of roasted limonite is improved, thereby improving the roasting quality. Summary of the invention

[0003] The invention aims to provide a temperature-controlled roasting rotary kiln, which can solve the ringing phenomenon caused by local overheating, ensure that the reaction temperature in the kiln is controllable and uniform, the reducing atmosphere is fully stable, the ore powder is fully in contact with the reducing gas, and the magnetization reduction efficiency of roasting limonite is improved, thereby improving the roasting quality.

[0004] The technical solution of the present invention is: a temperature-controlled roasting rotary kiln, comprising a furnace body, a heat-insulating layer, an air blowing system, a combustion chamber, a burner, a feeder, a silo, and a discharge port. The furnace body is a cylindrical structure, a feeder is installed in the middle of one end face of the furnace body, and the feeder is a rotary feeder. The cylinder wall close to the other end face of the furnace body is equipped with a discharge port. The inner wall of the furnace body is provided with a heat-insulating layer, and the heat-insulating layer is successively composed of a heat-insulating layer and a lining plate from the outside to the inside. The heat-insulating layer is built of refractory materials. The lining plate is assembled from metal lining plates, and the blowing system includes a direct blowing air pipe, which is arranged at the center of the end surface of the furnace body close to the discharge port, and is connected to an external gas source. The outer wall of the furnace body is provided with a combustion chamber, and the combustion chamber shell is a steel structure with a refractory material lined inside. The combustion chamber is equipped with a burner, and the burner is connected to an external combustion gas source. The combustion chamber is connected to the furnace body through a heat transfer pipe, and a thermocouple is installed on the side wall of the combustion chamber.

[0005] As described above, the temperature-controlled roasting rotary kiln, the blowing system also includes an inner preheating pipe and an inner blowing pipe, a pipe groove is provided in the lining plate, the inner preheating pipe is matched and installed in the pipe groove, the inner blowing pipe is provided on the lining plate, one end of the inner preheating pipe is connected to the inner preheating pipe, and the other end leads to the inner cavity of the furnace body, and the inner preheating pipe is connected to an external gas source.

[0006] In the temperature-controlled roasting rotary kiln as described above, there are 5 to 10 combustion chambers, which are evenly and cross-distributed on the circumferential surface of the outer wall of the furnace body, and the combustion chambers are staggered in sequence at the same angle.

[0007] In the temperature-controlled roasting rotary kiln as described above, the distance between adjacent combustion chambers is 8-15 meters.

[0008] In the temperature-controlled roasting rotary kiln as described above, the distance between the inner air blowing pipe and the end face of the furnace body where the direct air blowing pipe is located is 20-40 meters, and there are 6-18 inner air blowing pipes and inner preheating pipes respectively.

[0009] The temperature-controlled roasting rotary kiln as described above, the lining includes lining I and lining II, the lining I and lining II are circular ring segment metal bodies with the same cross-section, the outer surface shapes of lining I and lining II match the inner edge shape of the furnace body after the insulation layer is built, the annular lining body composed of lining I and the annular lining body composed of lining II are arranged alternately, the outer end faces of lining I and lining II are provided with T-shaped through-hole mounting grooves, the hanger is a steel structure, one end is T-shaped, and the other end is a rod-shaped with threads, the T-shaped body of the hanger matches the shape of the mounting groove, and the pipe groove is arranged at the lower part of the mounting groove.

[0010] As described above, in the temperature-controlled roasting rotary kiln, a lath-shaped pressing strip is provided on the outer side of the inner edge of the lining plate I, and a notch-shaped pressing plate groove is provided on the inner edge of the lining plate II, and the pressing strip matches the shape of the pressing plate groove.

[0011] Based on the above-mentioned masonry method of a temperature-controlled roasting rotary kiln, the masonry steps are: ① Remove rust and clean the inner surface of the furnace; ② Open installation holes on the wall of the furnace body, and the positions of the holes match the positions of lining plates I and II; ③ Spray and pour refractory materials on the inner wall of the furnace body, and reserve the installation hole slots on the furnace body wall; ④ Start assembling lining plates I and II. Assemble lining plate II near the end of the furnace body. During assembly, match the T-shaped body of the suspension rod with the installation slot of lining plate II, extend the rod-shaped end of the suspension rod from the installation hole slot opened on the furnace body wall, and fasten it with bolts and the threaded end of the suspension rod. Assemble lining plate II into an annular lining body according to the inner wall circumference of the furnace body; After reserving the position of lining plate I, assemble a circle of lining plate II; ⑤ After matching the T-shaped body of the suspension rod with the mounting groove of the liner plate I, extend the rod-shaped end of the suspension rod from the mounting hole groove position opened on the furnace wall, and fasten it with bolts and threads on the rod-shaped end of the suspension rod, liner plate I (12); ⑥ When assembling lining plates I and II, assemble the inner air blowing pipe and the inner preheating pipe at the same time.

[0012] A roasting rotary kiln roasting process based on the temperature-controlled roasting rotary kiln as described above includes a feeding process, a temperature control process, a reducing atmosphere control process, and an equipment operation process. The feeding process includes: the particle size range of the kiln is controlled within the range of 0.5-50 mm in diameter, the kiln material flows from the silo into the feeder), and is evenly fed into the rotary kiln through the feeder; The temperature control process includes: by burning the combustible gas in the burner, the temperature in the combustion chamber is increased, the high-temperature gas enters the rotary kiln through the heat transfer pipe, and the temperature in the kiln is controlled at 750-950 degrees Celsius through the heat transfer pipe. The high-temperature gas is supplied to the rotary kiln through the combustion chambers set at different positions, and the temperature in the kiln is stably controlled within a certain range, and the temperature in the kiln is kept uniform. The stable temperature in the kiln provides temperature guarantee for the processing of the kiln materials; The reducing atmosphere control process: an external gas source enters the inner preheating tube through a pipeline, the lining plate preheats the gas in the inner preheating tube, and the preheated gas is blown into the kiln through a direct blowing gas pipe, the gas temperature is 750-800 degrees Celsius, and the gas pressure in the kiln is 1.01-1.05 atmospheres after the gas is blown in; The equipment operation process: the rotary kiln has an inclination angle of 1-5 degrees and a rotary kiln speed of 0.5-5 revolutions per minute.

[0013] In the roasting rotary kiln roasting process as described above, a temperature measuring and controlling device is provided in the furnace body, a combustion control device is provided on the burner, and an air supply device is provided on the heat transfer tube. The temperature measuring and controlling device is connected and controlled with the burner combustion control device and the heat transfer tube air supply device. The temperature change data in the furnace body is adjusted by the burner combustion control device to control the combustion temperature of the combustion chamber, and the air supply flow of the heat transfer tube is regulated by the heat transfer tube air supply device.

[0014] The beneficial effects of the present invention are as follows: the design structure, masonry process and roasting process of the device are reasonable. By using the metal lining, the service life of the furnace lining is increased and the occurrence of lining adhesion is reduced. By using the temperature control technology, the local high temperature area in the kiln is eliminated, thereby avoiding the occurrence of ring formation. The high temperature reducing gas is sprayed into the middle of the kiln body to ensure full contact with the mineral powder in the kiln and improve the efficiency of the reduction reaction. The kiln maintains a constant high temperature, which improves the roasting efficiency and roasting quality. The kiln body has a long service life and significant economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a schematic diagram of the structure of the device of the present invention; Figure 2 This is a partial enlarged view of the preheating pipe and the internal air blowing pipe in the device of the present invention; Figure 3 This is a front view of the liner plate I of the device of the present invention; Figure 4 It is a top view of the liner plate I of the device of the present invention; Figure 5 It is a cross-sectional view of the liner plate I of the device of the present invention; Figure 6 This is the front view of the liner II of the device of the present invention; Figure 7 It is a side view of liner II of the device of the present invention; Figure 8 It is a cross-sectional view of the liner II of the device of the present invention; Fig. 9 It is a schematic diagram of the suspension rod of the device of the present invention; Markings in the figure: furnace body 1, lining 2, thermocouple 3, direct blowing air pipe 4, combustion chamber 5, burner 6, heat transfer pipe 7, sealing device 8, feeder 9, silo 10, discharge port 11, lining plate I 12, lining plate II 13, mounting groove 14, pressure plate strip 15, pressure plate groove 16, insulation layer 17, hanger 18, inner preheating pipe 19, inner blowing air pipe 20, pipe groove 21. DETAILED DESCRIPTION

[0016] The invention is further described below by way of examples with reference to the accompanying drawings. Example

[0017] Referring to the accompanying drawings, a temperature-controlled roasting rotary kiln includes a furnace body 1, an insulation layer, an air blowing system, a combustion chamber 5, a burner 6, a feeder 9, a silo 10, and a discharge port 11. The furnace body 1 is a cylindrical structure. The middle part of one end surface of the furnace body 1 is equipped with a feeder 9, and the feeder 9 is a rotary feeder. The cylinder wall close to the other end surface of the furnace body 1 is equipped with a discharge port 11. The inner wall of the furnace body 1 is provided with an insulation layer. The insulation layer is sequentially an insulation layer 17 and a lining plate 2 from the outside to the inside. The insulation layer 17 is built of refractory materials. The lining plate 2 is assembled from metal lining plates, and the blowing system includes a direct blowing air pipe 4, which is arranged at the center of the end surface of the furnace body 1 near the discharge port 11, and is connected to an external gas source. The outer wall of the furnace body 1 is provided with a combustion chamber 5, and the outer shell of the combustion chamber 5 is a steel structure, and the interior is lined with refractory materials. The combustion chamber 5 is equipped with a burner 6, and the burner 6 is connected to an external combustion gas source. The combustion chamber 5 is connected to the furnace body 1 through a heat transfer pipe 7, and a thermocouple 3 is installed on the side wall of the combustion chamber 5. The blowing system also includes an inner preheating pipe 19 and an inner blowing pipe 20. A pipe groove 21 is arranged in the lining plate 2, and the inner preheating pipe 19 is matched and installed in the pipe groove 21. The inner blowing pipe 20 is arranged on the lining plate 2, one end of which is connected to the inner preheating pipe 19, and the other end passes into the inner cavity of the furnace body 1, and the inner preheating pipe 19 is connected to an external gas source. There are eight combustion chambers 5, which are evenly distributed on the outer circumferential surface of the furnace body 1, and the combustion chambers 5 are staggered in sequence at the same angle. The distance between adjacent combustion chambers 5 is 10 meters. The distance between the position of the inner air blowing pipe 20 and the end face of the furnace body 1 where the direct air blowing pipe 4 is located is 30 meters. There are 12 inner air blowing pipes 20 and 12 inner preheating pipes 19. The lining plate 2 includes lining plate I 12 and lining plate II 13. The lining plate I 12 and lining plate II 13 are circular ring metal bodies with the same cross-section. The outer surface shapes of the lining plate I 12 and lining plate II 13 match the inner edge shape of the furnace body 1 after the thermal insulation layer 17 is built. The annular lining body composed of the lining plate I 12 and the annular lining body composed of the lining plate II 13 are arranged alternately. The outer end faces of the lining plate I 12 and lining plate II 13 are provided with T-shaped through-hole mounting grooves 14. The suspension rod 18 is a steel structure, one end of which is T-shaped and the other end is a rod-shaped with threads. The T-shaped body of the suspension rod 18 matches the shape of the mounting groove 14. The pipe groove 21 is arranged at the lower part of the mounting groove 14. The inner edge of the lining plate I 12 is provided with a plate-shaped pressure plate strip 15, and the inner edge of the lining plate II 13 is provided with a notch-shaped pressure plate groove 16. The pressure plate strip 15 matches the shape of the pressure plate groove 16.

[0018] A masonry method for a temperature-controlled roasting rotary kiln based on the above device, the masonry steps are: ① Derust and clean the inner surface of the furnace body 1; ② Opening installation holes on the wall of the furnace body 1, the positions of the holes match the positions of the lining plate Ⅰ12 and the lining plate Ⅱ13; ③ Spray and pour refractory materials on the inner wall of the furnace body 1, and reserve the installation hole slot positions opened on the wall of the furnace body 1; ④ Start assembling lining plate I12 and lining plate II13. Assemble lining plate II13 near the end of furnace body 1. During assembly, match and assemble the T-shaped body of suspension rod 18 with the mounting groove 14 of lining plate II13, extend the rod-shaped end of suspension rod 18 from the mounting hole groove position opened on the wall of furnace body 1, and fasten with bolts and the threaded end of suspension rod 18 to assemble lining plate II13 into an annular lining body according to the circumference of the inner wall of furnace body 1; after reserving the position of lining plate I12, assemble a circle of lining plate II13; ⑤ After the T-shaped body of the suspension rod 18 is matched and assembled with the mounting groove 14 of the liner Ⅰ12, the rod-shaped end of the suspension rod 18 is extended from the mounting hole groove position opened on the wall of the furnace body 1, and the rod-shaped end of the suspension rod 17 is threadedly assembled and fastened with bolts, and the liner Ⅰ12; ⑥ When lining plate Ⅰ12 and lining plate Ⅱ13 are assembled, the inner air blowing pipe 20 and the inner preheating pipe 19 are assembled at the same time.

[0019] A roasting rotary kiln roasting process based on the temperature-controlled roasting rotary kiln as described above includes a feeding process, a temperature control process, a reducing atmosphere control process, and an equipment operation process. The feeding process includes: the particle size range of the kiln is controlled within the range of 0.5-50 mm in diameter, the kiln material flows from the silo 10 into the feeder 9, and is uniformly fed into the rotary kiln through the feeder 9; The temperature control process includes: the temperature in the combustion chamber 5 is increased by burning the combustible gas in the burner 6, the high-temperature gas enters the rotary kiln through the heat transfer pipe 7, and the temperature of the kiln is controlled at 850 degrees Celsius by blowing into the kiln through the heat transfer pipe 7, and the high-temperature gas is supplied to the rotary kiln through the combustion chambers 5 arranged at different positions, so that the temperature in the kiln is stably controlled within a certain range, and the temperature in the kiln is kept uniform. The stable temperature in the kiln provides temperature guarantee for the processing of the kiln materials; The reducing atmosphere control process: the external gas source enters the inner preheating tube 19 through the pipeline, the lining plate 2 preheats the gas in the inner preheating tube 19, and the preheated gas is blown into the kiln through the direct blowing pipe 4. The temperature of the blown gas is 770 degrees Celsius, and the pressure in the kiln is 1.03 atmospheres after the gas is blown in. The equipment operation process: the rotary kiln has an inclination angle of 3 degrees and a rotary kiln speed of 3 revolutions per minute.

[0020] The furnace body 1 is provided with a temperature measuring and controlling device, the burner 6 is provided with a combustion control device, and the heat transfer tube 7 is provided with an air supply device. The temperature measuring and controlling device is connected and controlled with the combustion control device of the burner 6 and the air supply device of the heat transfer tube 7. The temperature change data in the furnace body 1 is adjusted by the combustion control device of the burner 6 to adjust the burner combustion to control the heating temperature of the combustion chamber, and the air supply flow of the heat transfer tube 7 is regulated by the air supply device of the heat transfer tube 7.

[0021] The design structure, masonry process and roasting process of this device are reasonable. The use of metal lining increases the service life of the furnace lining and reduces the occurrence of lining adhesion. Through the use of temperature control technology, the local high temperature area in the kiln is eliminated, thereby avoiding the occurrence of ring formation. High-temperature reducing gas is sprayed into the middle of the kiln body to ensure full contact with the mineral powder in the kiln and improve the efficiency of the reduction reaction. The kiln maintains a constant high temperature, which improves the roasting efficiency and quality. The kiln body has a long service life and significant economic benefits.

[0022] Example 2 Referring to the accompanying drawings, a temperature-controlled roasting rotary kiln includes a furnace body 1, an insulation layer, an air blowing system, a combustion chamber 5, a burner 6, a feeder 9, a silo 10, and a discharge port 11. The furnace body 1 is a cylindrical structure. The middle part of one end surface of the furnace body 1 is equipped with a feeder 9, and the feeder 9 is a rotary feeder. The cylinder wall close to the other end surface of the furnace body 1 is equipped with a discharge port 11. The inner wall of the furnace body 1 is provided with an insulation layer. The insulation layer is sequentially an insulation layer 17 and a lining plate 2 from the outside to the inside. The insulation layer 17 is built of refractory materials. The lining plate 2 is assembled from metal lining plates, and the blowing system includes a direct blowing air pipe 4, which is arranged at the center of the end surface of the furnace body 1 near the discharge port 11, and is connected to an external gas source. The outer wall of the furnace body 1 is provided with a combustion chamber 5, and the outer shell of the combustion chamber 5 is a steel structure, and the interior is lined with refractory materials. The combustion chamber 5 is equipped with a burner 6, and the burner 6 is connected to an external combustion gas source. The combustion chamber 5 is connected to the furnace body 1 through a heat transfer pipe 7, and a thermocouple 3 is installed on the side wall of the combustion chamber 5. The blowing system also includes an inner preheating pipe 19 and an inner blowing pipe 20. A pipe groove 21 is arranged in the lining plate 2, and the inner preheating pipe 19 is matched and installed in the pipe groove 21. The inner blowing pipe 20 is arranged on the lining plate 2, one end of which is connected to the inner preheating pipe 19, and the other end passes into the inner cavity of the furnace body 1, and the inner preheating pipe 19 is connected to an external gas source. There are five combustion chambers 5, which are evenly distributed on the outer circumferential surface of the furnace body 1, and the combustion chambers 5 are staggered in sequence at the same angle. The distance between adjacent combustion chambers 5 is 15 meters. The distance between the position of the inner air blowing pipe 20 and the end face of the furnace body 1 where the direct air blowing pipe 4 is located is 22 meters. There are 18 inner air blowing pipes 20 and 18 inner preheating pipes 19. The lining plate 2 includes lining plate I 12 and lining plate II 13. The lining plate I 12 and lining plate II 13 are circular ring metal bodies with the same cross-section. The outer surface shapes of the lining plate I 12 and lining plate II 13 match the inner edge shape of the furnace body 1 after the thermal insulation layer 17 is built. The annular lining body composed of the lining plate I 12 and the annular lining body composed of the lining plate II 13 are arranged alternately. The outer end faces of the lining plate I 12 and lining plate II 13 are provided with T-shaped through-hole mounting grooves 14. The suspension rod 18 is a steel structure, one end of which is T-shaped and the other end is a rod-shaped with threads. The T-shaped body of the suspension rod 18 matches the shape of the mounting groove 14. The pipe groove 21 is arranged at the lower part of the mounting groove 14. The inner edge of the lining plate I 12 is provided with a plate-shaped pressure plate strip 15, and the inner edge of the lining plate II 13 is provided with a notch-shaped pressure plate groove 16. The pressure plate strip 15 matches the shape of the pressure plate groove 16.

[0023] A masonry method for a temperature-controlled roasting rotary kiln based on the above device, the masonry steps are: ① Derust and clean the inner surface of the furnace body 1; ② Opening installation holes on the wall of the furnace body 1, the positions of the holes match the positions of the lining plate Ⅰ12 and the lining plate Ⅱ13; ③ Spray and pour refractory materials on the inner wall of the furnace body 1, and reserve the installation hole slot positions opened on the wall of the furnace body 1; ④ Start assembling lining plate I12 and lining plate II13. Assemble lining plate II13 near the end of furnace body 1. During assembly, match and assemble the T-shaped body of suspension rod 18 with the mounting groove 14 of lining plate II13, extend the rod-shaped end of suspension rod 18 from the mounting hole groove position opened on the wall of furnace body 1, and fasten with bolts and the threaded end of suspension rod 18 to assemble lining plate II13 into an annular lining body according to the circumference of the inner wall of furnace body 1; after reserving the position of lining plate I12, assemble a circle of lining plate II13; ⑤ After the T-shaped body of the suspension rod 18 is matched and assembled with the mounting groove 14 of the liner Ⅰ12, the rod-shaped end of the suspension rod 18 is extended from the mounting hole groove position opened on the wall of the furnace body 1, and the rod-shaped end of the suspension rod 17 is threadedly assembled and fastened with bolts, and the liner Ⅰ12; ⑥ When lining plate Ⅰ12 and lining plate Ⅱ13 are assembled, the inner air blowing pipe 20 and the inner preheating pipe 19 are assembled at the same time.

[0024] A roasting rotary kiln roasting process based on the temperature-controlled roasting rotary kiln as described above includes a feeding process, a temperature control process, a reducing atmosphere control process, and an equipment operation process. The feeding process includes: the particle size range of the kiln is controlled within the range of 0.5-50 mm in diameter, the kiln material flows from the silo 10 into the feeder 9, and is uniformly fed into the rotary kiln through the feeder 9; The temperature control process includes: the temperature in the combustion chamber 5 is increased by burning the combustible gas in the burner 6, the high-temperature gas enters the rotary kiln through the heat transfer pipe 7, and the temperature in the kiln is controlled at 948 degrees Celsius by blowing into the kiln through the heat transfer pipe 7, and the high-temperature gas is supplied to the rotary kiln through the combustion chambers 5 arranged at different positions, so that the temperature in the kiln is stably controlled within a certain range, and the temperature in the kiln is kept uniform. The stable temperature in the kiln provides temperature guarantee for the processing of the kiln materials; The reducing atmosphere control process: the external gas source enters the inner preheating tube 19 through the pipeline, the lining plate 2 preheats the gas in the inner preheating tube 19, and the preheated gas is blown into the kiln through the direct blowing gas pipe 4. The temperature of the blown gas is 752 degrees Celsius, and the gas pressure in the kiln is 1.01 atmospheres after the gas is blown in. The equipment operation process: the rotary kiln has an inclination angle of 13 degrees and a rotary kiln speed of 5 revolutions per minute.

[0025] The furnace body 1 is provided with a temperature measuring and controlling device, the burner 6 is provided with a combustion control device, and the heat transfer tube 7 is provided with an air supply device. The temperature measuring and controlling device is connected and controlled with the combustion control device of the burner 6 and the air supply device of the heat transfer tube 7. The temperature change data in the furnace body 1 is adjusted by the combustion control device of the burner 6 to adjust the burner combustion to control the heating temperature of the combustion chamber, and the air supply flow of the heat transfer tube 7 is regulated by the air supply device of the heat transfer tube 7.

[0026] The design structure, masonry process and roasting process of this device are reasonable. The use of metal lining increases the service life of the furnace lining and reduces the occurrence of lining adhesion. Through the use of temperature control technology, the local high temperature area in the kiln is eliminated, thereby avoiding the occurrence of ring formation. High-temperature reducing gas is sprayed into the middle of the kiln body to ensure full contact with the mineral powder in the kiln and improve the efficiency of the reduction reaction. The kiln maintains a constant high temperature, which improves the roasting efficiency and quality. The kiln body has a long service life and significant economic benefits.

[0027] Example 3 Referring to the accompanying drawings, a temperature-controlled roasting rotary kiln includes a furnace body 1, an insulation layer, an air blowing system, a combustion chamber 5, a burner 6, a feeder 9, a silo 10, and a discharge port 11. The furnace body 1 is a cylindrical structure. The middle part of one end surface of the furnace body 1 is equipped with a feeder 9, and the feeder 9 is a rotary feeder. The cylinder wall close to the other end surface of the furnace body 1 is equipped with a discharge port 11. The inner wall of the furnace body 1 is provided with an insulation layer. The insulation layer is sequentially an insulation layer 17 and a lining plate 2 from the outside to the inside. The insulation layer 17 is built of refractory materials. The lining plate 2 is assembled from metal lining plates, and the blowing system includes a direct blowing air pipe 4, which is arranged at the center of the end surface of the furnace body 1 near the discharge port 11, and is connected to an external gas source. The outer wall of the furnace body 1 is provided with a combustion chamber 5, and the outer shell of the combustion chamber 5 is a steel structure, and the interior is lined with refractory materials. The combustion chamber 5 is equipped with a burner 6, and the burner 6 is connected to an external combustion gas source. The combustion chamber 5 is connected to the furnace body 1 through a heat transfer pipe 7, and a thermocouple 3 is installed on the side wall of the combustion chamber 5. The blowing system also includes an inner preheating pipe 19 and an inner blowing pipe 20. A pipe groove 21 is arranged in the lining plate 2, and the inner preheating pipe 19 is matched and installed in the pipe groove 21. The inner blowing pipe 20 is arranged on the lining plate 2, one end of which is connected to the inner preheating pipe 19, and the other end passes into the inner cavity of the furnace body 1, and the inner preheating pipe 19 is connected to an external gas source. There are 10 combustion chambers 5, which are evenly distributed on the outer circumferential surface of the furnace body 1, and the combustion chambers 5 are staggered in sequence at the same angle. The distance between adjacent combustion chambers 5 is 8 meters. The distance between the position of the inner air blowing pipe 20 and the end face of the furnace body 1 where the direct air blowing pipe 4 is located is 38 meters, and there are 8 inner air blowing pipes 20 and 8 inner preheating pipes 19 respectively. The lining plate 2 includes lining plate I 12 and lining plate II 13. The lining plate I 12 and lining plate II 13 are circular ring metal bodies with the same cross-section. The outer surface shapes of the lining plate I 12 and lining plate II 13 match the inner edge shape of the furnace body 1 after the thermal insulation layer 17 is built. The annular lining body composed of the lining plate I 12 and the annular lining body composed of the lining plate II 13 are arranged alternately. The outer end faces of the lining plate I 12 and lining plate II 13 are provided with T-shaped through-hole mounting grooves 14. The suspension rod 18 is a steel structure, one end of which is T-shaped and the other end is a rod-shaped with threads. The T-shaped body of the suspension rod 18 matches the shape of the mounting groove 14. The pipe groove 21 is arranged at the lower part of the mounting groove 14. The inner edge of the lining plate I 12 is provided with a plate-shaped pressure plate strip 15, and the inner edge of the lining plate II 13 is provided with a notch-shaped pressure plate groove 16. The pressure plate strip 15 matches the shape of the pressure plate groove 16.

[0028] A masonry method for a temperature-controlled roasting rotary kiln based on the above device, the masonry steps are: ① Derust and clean the inner surface of the furnace body 1; ② Opening installation holes on the wall of the furnace body 1, the positions of the holes match the positions of the lining plate Ⅰ12 and the lining plate Ⅱ13; ③ Spray and pour refractory materials on the inner wall of the furnace body 1, and reserve the installation hole slot positions opened on the wall of the furnace body 1; ④ Start assembling lining plate I12 and lining plate II13. Assemble lining plate II13 near the end of furnace body 1. During assembly, match and assemble the T-shaped body of suspension rod 18 with the mounting groove 14 of lining plate II13, extend the rod-shaped end of suspension rod 18 from the mounting hole groove position opened on the wall of furnace body 1, and fasten with bolts and the threaded end of suspension rod 18 to assemble lining plate II13 into an annular lining body according to the circumference of the inner wall of furnace body 1; after reserving the position of lining plate I12, assemble a circle of lining plate II13; ⑤ After the T-shaped body of the suspension rod 18 is matched and assembled with the mounting groove 14 of the liner Ⅰ12, the rod-shaped end of the suspension rod 18 is extended from the mounting hole groove position opened on the wall of the furnace body 1, and the rod-shaped end of the suspension rod 17 is threadedly assembled and fastened with bolts, and the liner Ⅰ12; ⑥ When lining plate Ⅰ12 and lining plate Ⅱ13 are assembled, the inner air blowing pipe 20 and the inner preheating pipe 19 are assembled at the same time.

[0029] A roasting rotary kiln roasting process based on the temperature-controlled roasting rotary kiln as described above includes a feeding process, a temperature control process, a reducing atmosphere control process, and an equipment operation process. The feeding process includes: the particle size range of the kiln is controlled within the range of 0.5-50 mm in diameter, the kiln material flows from the silo 10 into the feeder 9, and is uniformly fed into the rotary kiln through the feeder 9; The temperature control process includes: the temperature in the combustion chamber 5 is increased by burning the combustible gas in the burner 6, the high-temperature gas enters the rotary kiln through the heat transfer pipe 7, and the temperature of the kiln is controlled at 752 degrees Celsius by blowing into the kiln through the heat transfer pipe 7, and the high-temperature gas is supplied to the rotary kiln through the combustion chambers 5 arranged at different positions, so that the temperature in the kiln is stably controlled within a certain range, and the temperature in the kiln is kept uniform. The stable temperature in the kiln provides temperature guarantee for the processing of the kiln materials; The reducing atmosphere control process: the external gas source enters the inner preheating tube 19 through the pipeline, the lining plate 2 preheats the gas in the inner preheating tube 19, and the preheated gas is blown into the kiln through the direct blowing pipe 4. The blown gas temperature is 795 degrees Celsius, and the gas pressure in the kiln is 1.045 atmospheres after the gas is blown in. The equipment operation process: the rotary kiln has an inclination angle of 4.5 degrees and a rotary kiln speed of 1 revolution per minute.

[0030] The furnace body 1 is provided with a temperature measuring and controlling device, the burner 6 is provided with a combustion control device, and the heat transfer tube 7 is provided with an air supply device. The temperature measuring and controlling device is connected and controlled with the combustion control device of the burner 6 and the air supply device of the heat transfer tube 7. The temperature change data in the furnace body 1 is adjusted by the combustion control device of the burner 6 to adjust the burner combustion to control the heating temperature of the combustion chamber, and the air supply flow of the heat transfer tube 7 is regulated by the air supply device of the heat transfer tube 7.

[0031] The design structure, masonry process and roasting process of this device are reasonable. The use of metal lining increases the service life of the furnace lining and reduces the occurrence of lining adhesion. Through the use of temperature control technology, the local high temperature area in the kiln is eliminated, thereby avoiding the occurrence of ring formation. High-temperature reducing gas is sprayed into the middle of the kiln body to ensure full contact with the mineral powder in the kiln and improve the efficiency of the reduction reaction. The kiln maintains a constant high temperature, which improves the roasting efficiency and quality. The kiln body has a long service life and significant economic benefits.

Claims

1. A temperature-controlled roasting rotary kiln, characterized in that The invention comprises a furnace body (1), an insulation layer, an air blowing system, a combustion chamber (5), a burner (6), a feeder (9), a silo (10), and a discharge port (11), wherein the furnace body (1) is a cylindrical structure, a feeder (9) is mounted in the middle of one end surface of the furnace body (1), the feeder (9) is a rotary feeder, a discharge port (11) is mounted on the cylinder wall close to the other end surface of the furnace body (1), an insulation layer is arranged on the inner wall of the furnace body (1), and the insulation layer is sequentially arranged from the outside to the inside, the insulation layer (17) is made of refractory material, and the lining plate (2) is a metal lining. The furnace body (1) is assembled from a plurality of plates, the blowing system comprising a direct blowing air pipe (4), the direct blowing air pipe (4) being arranged at the center of the end surface of the furnace body (1) close to the discharge port (11), the direct blowing air pipe (4) being connected to an external gas source, the outer wall of the furnace body (1) being provided with a combustion chamber (5), the outer shell of the combustion chamber (5) being a steel structure, the interior of which is lined with refractory material, the combustion chamber (5) being equipped with a burner (6), the burner (6) being connected to an external combustion gas source, the combustion chamber (5) being connected to the furnace body (1) via a heat transfer pipe (7) arranged inside, and a thermocouple (3) being arranged on the side wall of the combustion chamber (5).

2. The temperature-controlled roasting rotary kiln according to claim 1, characterized in that The air blowing system further comprises an inner preheating pipe (19) and an inner air blowing pipe (20); a pipe groove (21) is provided in the lining plate (2); the inner preheating pipe (19) is matched and installed in the pipe groove (21); the inner air blowing pipe (20) is arranged on the lining plate (2); one end of the inner preheating pipe (19) is connected to the inner preheating pipe (19) and the other end is passed into the inner cavity of the furnace body (1); the inner preheating pipe (19) is connected to an external air source.

3. The temperature-controlled roasting rotary kiln according to claim 1, characterized in that There are 5 to 10 combustion chambers (5), which are evenly and cross-distributed on the circumferential surface of the outer wall of the furnace body (1), and the combustion chambers (5) are staggered in sequence at the same angle.

4. The temperature-controlled roasting rotary kiln according to claim 1, characterized in that The distance between adjacent combustion chambers (5) is 8-15 meters.

5. The temperature-controlled roasting rotary kiln according to claim 2, characterized in that The distance between the position of the inner air blowing pipe (20) and the end face of the furnace body (1) where the direct air blowing pipe (4) is located is 20-40 meters, and there are 6-18 inner air blowing pipes (20) and inner preheating pipes (19) respectively.

6. The temperature-controlled roasting rotary kiln according to claim 1, characterized in that The lining plate (2) comprises a lining plate I (12) and a lining plate II (13). The lining plate I (12) and the lining plate II (13) are circular ring segment metal bodies with the same cross-section. The outer surface shapes of the lining plate I (12) and the lining plate II (13) match the inner edge shape of the furnace body (1) after the thermal insulation layer (17) is built. The annular lining body composed of the lining plate I (12) and the annular lining body composed of the lining plate II (13) are arranged alternately. The outer end surfaces of the lining plate I (12) and the lining plate II (13) are provided with T-shaped through-hole mounting grooves (14). The suspension rod (18) is a steel structure, one end of which is T-shaped and the other end is a rod-shaped body provided with threads. The T-shaped body of the suspension rod (18) matches the shape of the mounting groove (14). The pipe groove (21) is provided at the lower part of the mounting groove (14).

7. The temperature-controlled roasting rotary kiln according to claim 6, characterized in that A plate-shaped pressing strip (15) is arranged on the outer side of the inner edge of the lining plate I (12), and a notch-shaped pressing plate groove (16) is arranged on the inner edge of the lining plate II (13), and the shapes of the pressing strip (15) and the pressing plate groove (16) match each other.

8. A masonry method for a temperature-controlled roasting rotary kiln according to any one of claims 1 to 7, characterized in that the masonry steps are: ① Cleaning and rust removal on the inner surface of the furnace body (1); ② Opening mounting holes on the wall of the furnace body (1), the positions of the holes matching the positions of the lining plate I (12) and the lining plate II (13); ③ Spraying and pouring refractory material on the inner wall of the furnace body (1) to reserve the position of the installation hole groove opened on the wall of the furnace body (1); ④ Start assembling the lining plate I (12) and the lining plate II (13). Assemble the lining plate II (13) at the position close to the end of the furnace body (1). During assembly, match the T-shaped body of the suspension rod (18) with the mounting groove (14) of the lining plate II (13), extend the rod-shaped end of the suspension rod (18) from the mounting hole groove position opened on the wall of the furnace body (1), and fasten it with bolts and the threaded end of the suspension rod (18). Assemble the lining plate II (13) according to the circumference of the inner wall of the furnace body (1) to form an annular lining body; after reserving the position of the lining plate I (12), assemble a circle of the lining plate II (13); ⑤ After the T-shaped body of the suspension rod (18) is matched and assembled with the mounting groove (14) of the lining plate I (12), the rod-shaped end of the suspension rod (18) is extended from the mounting hole groove position opened on the wall of the furnace body (1), and is screwed and fastened with the rod-shaped end of the suspension rod (17) by bolts, and the lining plate I (12); ⑥ When lining plate I (12) and lining plate II (13) are assembled, the inner air blowing pipe (20) and the inner preheating pipe (19) are assembled at the same time.

9. A roasting rotary kiln roasting process based on the temperature-controlled roasting rotary kiln according to any one of claims 1 to 7, characterized in that Including feeding process, temperature control process, reducing atmosphere control process, equipment operation process, The feeding process includes: controlling the particle size range of the kiln feed material to be within the range of 0.5-50 mm in diameter, the kiln feed material flows from the material bin (10) into the feeder (9), and is uniformly fed into the rotary kiln through the feeder (9); The temperature control process comprises: the temperature in the combustion chamber (5) is increased by burning the combustible gas in the burner (6), the high-temperature gas enters the rotary kiln through the heat transfer pipe (7), and the temperature of the kiln is controlled at 750-950 degrees Celsius by blowing the high-temperature gas into the kiln through the heat transfer pipe (7), and the high-temperature gas is supplied to the rotary kiln through the combustion chambers (5) arranged at different positions, so that the temperature in the kiln is stably controlled within a certain range, and the temperature in the kiln is kept uniform. The stable temperature in the kiln provides temperature guarantee for the processing of the kiln materials; The reducing atmosphere control process: an external coal gas source enters the inner preheating tube (19) through a pipeline, the lining plate (2) preheats the coal gas in the inner preheating tube (19), and the preheated coal gas is blown into the kiln through the direct blowing pipe (4), the blown gas temperature is 750-800 degrees Celsius, and the gas pressure in the kiln after the gas is blown in is 1.01-1.05 atmospheres; The equipment operation process: the rotary kiln has an inclination angle of 1-5 degrees and a rotary kiln speed of 0.5-5 revolutions per minute.

10. The roasting rotary kiln roasting process according to claim 9, characterized in that A temperature measurement and control device is provided in the furnace body (1), a combustion control device is provided in the burner (6), and an air supply device is provided in the heat transfer tube (7). The temperature measurement and control device is connected and controlled with the combustion control device of the burner (6) and the air supply device of the heat transfer tube (7). The temperature change data in the furnace body (1) is used to adjust the combustion of the burner through the combustion control device of the burner (6) to control the heating temperature of the combustion chamber, and the air supply flow rate of the heat transfer tube (7) is regulated through the air supply device of the heat transfer tube (7).

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