An environmentally friendly tunnel kiln

Abstract

The invention discloses an environmentally friendly tunnel kiln, comprising a kiln body, a material transport vehicle, a heating device, a denitration device, a heat exchanger, and a desulfurization and dust removal device. A feed port is arranged at one end of the kiln body, and a discharge port is arranged at the other end of the kiln body. A blank area, a preheating area, a combustion area, and a flue gas preheating module area are sequentially arranged in the kiln body from the feed port to the discharge port. A closed door is arranged at the feed port. The blank area, the preheating area, the combustion area, and the flue gas preheating module area are separated by an insulating door. A track is laid on the bottom side of the kiln body, and the material transport vehicle can pass through the kiln body from the feed port to the discharge port along the track. The invention has a simple structure, fully utilizes the exhaust gas generated in the tunnel kiln during the firing process of the blank brick material to preheat the blank brick material, fully utilizes energy, reduces the heating gradient of the blank brick material, saves energy and is environmentally friendly, and slowly heats the blank brick material in the blank area according to the temperature gradient of the flue gas, and its internal structural strength is slowly enhanced, thereby reducing the cracking degree and porosity of the blank brick material.

Description

Technical Field

[0001] The invention relates to the field of tunnel kiln environmental protection, and in particular to an environmentally friendly tunnel kiln. Background Art

[0002] The tunnel kiln was first used in 1765. At that time, it could only burn overglaze colors on ceramics. In 1810, it could be used to burn bricks or pottery. Since 1906, it has been used to burn porcelain bodies. The first famous tunnel kiln was the Fukielon type. After 1910, many improvements have gradually been made. The tunnel kiln is generally a long straight tunnel with fixed walls and arches on both sides and the top, and a kiln car running on the track laid at the bottom. The combustion equipment is located on both sides of the middle of the tunnel kiln, forming a fixed high-temperature zone - the firing zone. The high-temperature flue gas generated by the combustion flows along the tunnel to the kiln head under the action of the chimney or induced draft fan at the front end of the tunnel kiln, and gradually preheats the products entering the kiln. This section constitutes the preheating zone of the tunnel kiln. Cold air is blown in at the end of the tunnel kiln to cool the products in the last section of the tunnel kiln. After the blown cold air flows through the products and is heated, it is extracted and sent to the dryer as a heat source for drying the green body. This section constitutes the cooling zone of the tunnel kiln. The saggers filled with ceramic products are placed on the trolleys and are pushed in slowly and continuously from the entrance of the preheating zone (usually by machinery), while the trolleys carrying the fired products are gradually pushed out from the exit of the cooling zone (one trolley is pushed out every hour or so). Since the tunnel kiln is a continuous kiln, the heat utilization is better, and the combustion air used in most tunnel kilns is natural wind or cold air is blown into the cooling zone to make the air hot. Although the waste heat is utilized, because the extracted hot air is mixed with a lot of waste gas burned in the high temperature zone, there is insufficient oxygen in the combustion air, and the combustion effect is not good.

[0003] Tunnel kilns are widely used in the market now, but since a large amount of waste gas from the products produced during the firing process of tunnel kilns needs to be treated, it causes serious environmental pollution. The waste gas contains a large amount of heat energy, which causes energy waste. Summary of the invention

[0004] The technical problem to be solved by the present invention is to address the deficiencies in the above-mentioned prior art and disclose an environmentally friendly tunnel kiln, which fully utilizes the preheating in the exhaust gas to preheat the blank, thereby saving energy and being environmentally friendly.

[0005] The technical solution adopted by the present invention to solve its technical problem is:

[0006] An environmentally friendly tunnel kiln comprises a kiln body, a material transport vehicle, a heating device, a denitration device, a heat exchanger, and a desulfurization and dust removal device. A feed port is provided at one end of the kiln body, and a discharge port is provided at the other end of the kiln body. The kiln body is provided with a blank area, a preheating area, a combustion area, and a flue gas preheating module area in sequence from the feed port to the discharge port. A closed door is provided at the feed port. The blank area, the preheating area, the combustion area, and the flue gas preheating module area are separated by an insulating door. A track is laid on the bottom side of the kiln body. The material transport vehicle can pass through the kiln body from the feed port to the discharge port along the track. The inner top of the kiln body is inclined downward by 10 degrees from the blank area to the combustion area. Ventilation ducts are provided on the upper sides of the blank area, the preheating area, and the combustion area. A blank air outlet is provided on the upper side of the blank area. An A air inlet is arranged at the lower side of the flue gas preheating module area, the blank air outlet is connected to the A air inlet through a pipeline and an air pump is arranged on the pipeline, an A air outlet is arranged at the upper side of the flue gas preheating module area, the A air outlet is connected to the denitrification device through a pipeline, a heat exchanger is arranged at the lower side of the denitrification device, a clean air inlet is arranged at one end of the heat exchanger, the other end of the heat exchanger is connected to the preheating zone through a pipeline, the lower end of the denitrification device is connected to the desulfurization and dust removal device through a pipeline, a heater is arranged on the inner side of the combustion zone, a central control box and an alarm are arranged on the outer side of the kiln body, temperature sensors are arranged on the inner sides of the blank area, preheating zone, combustion zone and flue gas preheating module area, and the alarm, temperature sensor and air pump are electrically connected to the central control box respectively.

[0007] As a preferred embodiment of the present invention: the length of the blank area is seven meters.

[0008] As a preferred embodiment of the present invention: the length of the preheating zone is seven meters and the temperature of the preheating zone gradually increases from the blank zone to the combustion zone.

[0009] As a preferred embodiment of the present invention: the length of the flue gas preheating module area is seven meters.

[0010] As a preferred embodiment of the present invention: a square steel pipe support is arranged on the outer side of the kiln body, a porcelain plate is inlaid on the outer wall of the kiln body, and a thermal insulation lining is arranged on the inner side of the kiln body, and the thermal insulation lining is built with air-hardening mastic.

[0011] As a preferred embodiment of the present invention: a temperature compensator is arranged inside the preheating zone, and the temperature compensator is electrically connected to the central control box.

[0012] As a preferred embodiment of the present invention: the desulfurization and dust removal device is a glass fiber reinforced plastic cyclone desulfurization tower.

[0013] Compared with the prior art, the present invention has the following advantages:

[0014] 1. The present invention can fully utilize the preheating in the exhaust gas to preheat the blank, which is energy-saving and environmentally friendly;

[0015] 2. The flue gas can be purified through the denitrification device and the desulfurization and dust removal device to prevent air pollution;

[0016] 3. The heat exchanger can make clean air absorb the heat in the exhaust gas, which is convenient for preheating the preheating zone. According to the temperature gradient of the flue gas and the temperature gradient required during the firing process of the rough bricks, the rough bricks are slowly heated in the rough zone and the preheating zone, so that the internal structure strength is slowly enhanced, reducing the cracking degree and porosity of the rough bricks under instantaneous high temperature, and ensuring their quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of the present invention.

[0018] Description of reference numerals:

[0019] 1. Kiln body, 2. Material transport vehicle, 3. Heating device, 4. Denitrification device, 5. Heat exchanger, 6. Desulfurization and dust removal device, 7. Feed inlet, 8. Discharge outlet, 9. Blank area, 10. Preheating area, 11. Combustion area, 12. Flue gas preheating module area, 13. Track, 14. Blank air outlet, 15. A air inlet, 16. Air pump, 17. A air outlet, 18. Clean air inlet. DETAILED DESCRIPTION

[0020] The present invention is described in detail below in conjunction with the various embodiments shown in the accompanying drawings, but it should be noted that these embodiments are not limitations of the present invention, and any equivalent transformations or substitutions in functions, methods, or structures made by ordinary technicians in the field based on these embodiments are all within the scope of protection of the present invention.

[0021] like Figure 1As shown, it shows a specific embodiment of the present invention, including a kiln body 1, a material transport vehicle 2, a heating device 3, a denitrification device 4, a heat exchanger 5, and a desulfurization and dust removal device 6. One end of the kiln body 1 is provided with a feed port 7, and the other end of the kiln body 1 is provided with a discharge port 8. The kiln body 1 is provided with a blank area 9, a preheating area 10, a combustion area 11, and a flue gas preheating module area 12 in sequence from the feed port 7 to the discharge port 8. The feed port 7 is provided with a closed door. 11. The flue gas preheating module areas 12 are separated by an insulating door (allowing air flow to pass through). A track 13 is laid on the bottom side of the kiln body 1. The material transport vehicle 2 can pass through the kiln body 1 from the feed port 7 to the discharge port 8 along the track 13. The inner top of the kiln body 1 is inclined downward by 10 degrees from the blank area 9 to the combustion area 11. The upper sides of the blank area 9, the preheating area 10, and the combustion area 11 are provided with ventilation ducts. The upper side of the blank area 9 is provided with a blank outlet 14. The flue gas preheating module area 12 is provided with a heat exchanger. The lower side is provided with an A air inlet 15, the blank air outlet 14 is connected to the A air inlet 15 through a pipeline, and an air pump 16 is provided on the pipeline. The upper side of the flue gas preheating module area 12 is provided with an A air outlet 17, and the A air outlet 17 is connected to the denitration device 4 through a pipeline. The lower side of the denitration device 4 is provided with a heat exchanger 5, and one end of the heat exchanger 5 is provided with a clean air inlet 18, and the clean air inlet 18 can be blown into fresh air. The other end of the heat exchanger 5 is connected to the preheating zone 1 through a pipeline. 0 is connected, and the lower end of the denitrification device 4 is connected to the desulfurization and dust removal device 6 through a pipeline, that is, the fresh air blown in from the clean air inlet 18 is heat exchanged with the flue gas (the temperature can reach about 280°C) after denitrification entering the denitrification device 4 through the A air inlet 15. After the heat exchange, the temperature of the fresh air can be heated to about 150°C, and the hot flue gas after denitrification is cooled to about 120°C after heat exchange and enters the desulfurization and dust removal device 6, which ensures that the desulfurization and dust removal of the hot flue gas are carried out smoothly, and the hot flue gas is discharged after desulfurization and dust removal. The fresh air after heat exchange enters the preheating zone 10 through the pipeline. Under the action of the induced draft fan in the preheating zone 10 and the induced draft fan in the rough zone 9, the hot flue gas moves from the preheating zone 10 to the rough zone 9. During the movement, the temperature of the hot flue gas also decreases. The movement direction of the hot flue gas is opposite to that of the rough brick material, that is, the rough brick material moves from the rough zone 9 to the preheating zone 10, and the hot flue gas moves from the preheating zone 10 to the rough zone 9 (the temperature tends to decrease with the movement). The rough brick material is preheated slowly, which avoids the structural strength reduction, cracking and sand holes caused by the sudden high-temperature heating of its internal structure. The hot flue gas moving to the rough zone 9 is pumped from the rough zone 9 to the flue gas preheating module zone 12 under the action of the air pump 16. After preheating, it reaches the denitration temperature and enters the denitration device 4 from the pipeline for denitration.

[0022] A heater is arranged inside the combustion zone 11, a central control box and an alarm are arranged outside the kiln body, temperature sensors are arranged inside the blank zone 9, the preheating zone 10, the combustion zone 11 and the flue gas preheating module zone 12, and the alarm, the temperature sensor and the air pump 16 are electrically connected to the central control box respectively. The blank zone 9 is seven meters long, the preheating zone 10 is seven meters long and the temperature of the preheating zone 10 gradually increases from the blank zone 9 to the combustion zone 11, and the flue gas preheating module zone 12 is seven meters long. After the raw flue gas enters the flue gas preheating module area 12, the flue gas can be preheated to about 350°C to ensure that the flue gas enters the denitrification device 4 at this temperature (the flue gas has a good denitrification effect at this temperature). A square steel pipe bracket is arranged on the outside of the kiln body 1, and the outer wall of the kiln body 1 is inlaid with a porcelain plate. The inner side of the kiln body 1 is provided with an insulation lining, and the insulation lining is built with air-hardening clay. A temperature compensator is arranged on the inner side of the preheating zone 10, and the temperature compensator is electrically connected to the central control box. The desulfurization and dust removal device 6 is a glass fiber reinforced plastic cyclone desulfurization.

[0023] During the specific implementation of the present invention, the average temperature in the combustion zone 11 is 900°C, the upper side of the interior of the kiln body 1 is inclined downward by 10°C from the blank zone 9 to the combustion zone 11, and the high-temperature flue gas flows from the preheating zone 10 to the blank zone 9, and under the action of the air pump 16, flows to the A air inlet 15 through the blank air outlet 14, and after being preheated by the flue gas preheating module zone 12, it enters the denitrification device 4 through the A air outlet 17. The flue gas after denitrification is cooled down by the heat exchanger 5 and enters the desulfurization and dust removal device 6. The heat exchanger 5 heats the air entering through the clean air inlet 18, and the heated gas enters the preheating zone 10, thereby preheating the blanks in the preheating zone 10 and the blank zone 9. The present invention is energy-saving and environmentally friendly, has a controllable process, is simple to operate, and the equipment is easy to maintain and control. The temperature gradient of the flue gas is used to preheat the blank bricks in each firing interval, thereby ensuring the quality and strength of the bricks and reducing their cracking degree and sandstone rate.

[0024] The series of detailed descriptions listed above are only specific descriptions of feasible implementation methods of the present invention. They are not intended to limit the scope of protection of the present invention. Any equivalent implementation methods or changes that do not deviate from the technical spirit of the present invention should be included in the scope of protection of the present invention.

[0025] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. An environmentally friendly tunnel kiln, characterized by: The invention comprises a kiln body (1), a material transport vehicle (2), a heating device (3), a denitrification device (4), a heat exchanger (5), and a desulfurization and dust removal device (6). One end of the kiln body (1) is provided with a feed port (7), and the other end of the kiln body (1) is provided with a discharge port (8). The kiln body (1) is provided with a blank area (9), a preheating area (10), a combustion area (11), and a flue gas preheating module area (12) in sequence from the feed port (7) to the discharge port (8). A closed door is provided at the feed port (7). The preheating zone (10), the combustion zone (11), and the flue gas preheating module zone (12) are separated by an insulating door. A track (13) is laid on the bottom side of the kiln body (1). The material transport vehicle (2) can pass through the kiln body (1) from the feed port (7) to the discharge port (8) along the track (13). The inner top of the kiln body (1) is inclined downward by 10 degrees from the blank zone (9) to the combustion zone (11). The upper sides of the blank zone (9), the preheating zone (10), and the combustion zone (11) are provided with ventilation ducts. The upper side of the blank zone (9) is provided with a ventilation duct. A blank air outlet (14) is provided, an A air inlet (15) is provided on the lower side of the flue gas preheating module area (12), the blank air outlet (14) is connected to the A air inlet (15) through a pipeline, and an air pump (16) is provided on the pipeline, an A air outlet (17) is provided on the upper side of the flue gas preheating module area (12), the A air outlet (17) is connected to the denitrification device (4) through a pipeline, a heat exchanger (5) is provided on the lower side of the denitrification device (4), and a clean air inlet (18) is provided at one end of the heat exchanger (5). ), the other end of the heat exchanger (5) is connected to the preheating zone (10) through a pipeline, the lower end of the denitrification device (4) is connected to the desulfurization and dust removal device (6) through a pipeline, a heater is provided on the inner side of the combustion zone (11), a central control box and an alarm are provided on the outer side of the kiln body, and temperature sensors are provided on the inner sides of the blank zone (9), the preheating zone (10), the combustion zone (11), and the flue gas preheating module zone (12), and the alarm, temperature sensor, and air pump (16) are electrically connected to the central control box respectively; The blank area (9) is seven meters long; The length of the preheating zone (10) is seven meters and the temperature of the preheating zone (10) gradually increases from the blank zone (9) to the combustion zone (11).

2. The environmentally friendly tunnel kiln according to claim 1, characterized in that: The flue gas preheating module area (12) is seven meters long.

3. The environmentally friendly tunnel kiln according to claim 1, characterized in that: A square steel pipe bracket is provided on the outside of the kiln body (1), a porcelain plate is inlaid on the outer wall of the kiln body (1), and a thermal insulation lining is provided on the inside of the kiln body (1), and the thermal insulation lining is built with air-hardening clay.

4. The environmentally friendly tunnel kiln according to claim 1, characterized in that: A temperature compensator is provided inside the preheating zone (10), and the temperature compensator is electrically connected to the central control box.

5. The environmentally friendly tunnel kiln according to claim 1, characterized in that: The desulfurization and dust removal device (6) is a glass fiber reinforced plastic cyclone desulfurization tower.

Images