Dragon kiln flue gas waste heat recycling device

Abstract

The utility model discloses a dragon kiln flue gas waste heat recycling device which comprises a kiln body, a waste heat recycling chamber and a chimney, the interior of the waste heat recycling chamber is divided into an air inlet cavity, a heat exchange cavity and an air outlet cavity through two vertical walls, and the interior of the heat exchange cavity is divided into a plurality of firewood piling areas through a plurality of pipe rows. Each pipe row comprises a plurality of heat exchange pipes which are distributed at intervals and arranged in parallel, the two ends of each heat exchange pipe are communicated with the air inlet cavity and the air outlet cavity respectively, a sealing door is arranged on the side wall of the heat exchange cavity above each pipe row, a heat insulation layer is arranged on the outer wall of the kiln body, and an airflow layer is formed between the heat insulation layer and the outer wall of the kiln body. The airflow layer located at the kiln head end of the kiln body is blocked through a blocking plate, the airflow layer located at the kiln tail end of the kiln body is arranged in an open mode, and the airflow layer close to the blocking plate is communicated with the kiln head of the kiln body through a communicating pipe. The waste heat recovery device has the advantages that heat waste can be reduced, the heat utilization rate can be improved, and the waste heat recovery effect is good.

Description

Technical Field

[0001] The utility model relates to the technical field of waste heat recovery, and in particular to a dragon kiln flue gas waste heat recovery and utilization device. Background Art

[0002] Dragon kiln, also known as long kiln, originated in my country. It is a form of kiln in my country. It is a semi-continuous ceramic firing kiln. It is built on a certain slope and is named after its reclining dragon-like shape. It is widely used in firing ceramics for daily life in history. It has a history of about 1,500 years. Dragon kilns are mostly built on slopes in the Jiangnan region. Firewood is used as raw material when firing ceramics, so dragon kilns are also called firewood kilns. The success or failure of firewood-fired works depends on the relationship between people, soil, fire, firewood, and kilns. Burning firewood provides heat and ash. Generally, it takes three to five days to fire a kiln. During this period, it is necessary to take turns to add firewood without sleep. The speed and method of adding firewood, the type of new firewood, the climate conditions, the air intake flow rate and other subtle factors. In addition, when firing pottery in a dragon kiln, the completely burned ash is extremely light and will drift with the hot air flow. When the temperature reaches above 1200℃, the ash begins to melt and combines with the iron in the pottery to form gray glaze, showing different color changes.

[0003] The following problems often occur during the dragon kiln pottery firing process: due to the high moisture content of firewood, it is not dry enough, and the firewood is not completely burned due to stacking or insufficient oxygen during the burning process, which will produce a large amount of high-temperature flue gas. Part of the heat in these high-temperature flue gases will be absorbed by the pottery blanks and ash for the firing of pottery, but at the same time, part of the heat will be lost through the side walls of the dragon kiln, and a large amount of heat will be discharged from the chimney along with the flue gas. These heats are often not recovered and utilized but wasted, resulting in heat waste, reducing the utilization rate of heat, and also causing pollution to the surrounding environment. Therefore, it is objectively necessary to develop a dragon kiln flue gas waste heat recovery and utilization device for a wood-fired dragon kiln that can reduce heat waste, improve heat utilization, and have a good waste heat recovery effect. Utility Model Content

[0004] The utility model aims to provide a dragon kiln smoke waste heat recovery device for a wood-fired dragon kiln which can reduce heat waste, improve heat utilization and have a good waste heat recovery effect.

[0005] The purpose of the utility model is achieved in this way, including a kiln body, a waste heat recovery chamber and a chimney, the interior of the waste heat recovery chamber is divided into an air inlet chamber, a heat exchange chamber and an air outlet chamber by two vertical walls, the air inlet chamber is connected with the kiln tail of the kiln body, the top of the air outlet chamber is connected with the bottom of the chimney, the heat exchange chamber is divided into a plurality of firewood stacking areas by a plurality of pipe rows, each pipe row includes a plurality of heat exchange tubes that are spaced and arranged in parallel, both ends of each heat exchange tube are respectively connected with the air inlet chamber and the air outlet chamber, a sealing door is arranged on the side wall of the heat exchange chamber above each pipe row, a heat insulation layer is arranged on the outer wall of the kiln body, an airflow layer is formed between the heat insulation layer and the outer wall of the kiln body, the airflow layer at the kiln head end of the kiln body is blocked by a blocking plate, the airflow layer at the kiln tail end of the kiln body is openly arranged, and the airflow layer close to the blocking plate is connected with the kiln head of the kiln body through a connecting pipe.

[0006] Furthermore, an exhaust fan is provided on the connecting pipe.

[0007] Furthermore, a dehumidifier is arranged outside the waste heat recovery chamber, the air inlet end of the dehumidifier is connected to the top of the heat exchange chamber, and the air outlet end of the dehumidifier is connected to the bottom of the heat exchange chamber.

[0008] Furthermore, a water-cooled wall is provided on the inner wall of the chimney.

[0009] Furthermore, an upper ring pipe and a lower ring pipe are concentrically arranged at the upper and lower parts of the chimney respectively, and a plurality of vertical pipes are evenly distributed in the chimney. The upper ends of the vertical pipes are bent and connected to the upper ring pipe, and the lower ends of the vertical pipes are bent and connected to the lower ring pipe.

[0010] Furthermore, a plurality of supporting blocks are arranged between the heat insulating layer and the outer wall of the kiln body.

[0011] Furthermore, a plurality of heat-conducting rings are evenly spaced on the outer wall of the heat exchange tube along the length direction thereof.

[0012] Furthermore, an inclined plate is provided in the air outlet cavity.

[0013] When the utility model is in operation, the sealing door is opened, firewood is thrown into the firewood stacking area through the sealing door, the firewood is stacked on the pipe row, and the sealing door is closed after the stacking is completed. At the same time, pottery is fired in the kiln body of the dragon kiln, and the smoke exhausted from the kiln body and the kiln tail enters the air inlet cavity, then enters each heat exchange tube, passes into the air outlet cavity through the heat exchange tube, and is finally discharged through the chimney. In the above process, when the flue gas passes through the heat exchange tube, the heat is transferred to the firewood stacking area, heat exchange occurs with the firewood, the firewood is heated, the moisture in the firewood evaporates due to the heat, the moisture content of the firewood is reduced, and finally the purpose of drying the wood is achieved. The firewood is dried by utilizing the waste heat of the flue gas, which has a good waste heat recovery effect, improves the combustion efficiency of the firewood, reduces the waste of heat in the flue gas, and improves the utilization rate of heat; secondly, under the suction action of the chimney and the kiln body itself, the outside air enters the air flow layer from the tail end of the kiln body and continuously flows toward the head end of the kiln body. During the flow process, the heat emitted from the kiln body is absorbed and taken away, which has a good waste heat recovery effect. On the one hand, it avoids the loss and waste of heat, and on the other hand, it can also increase the temperature of the air, which plays a role in air preheating, so that after the air enters the kiln body, it can effectively improve the combustion efficiency of the firewood. In summary, the utility model uses the waste heat of flue gas to dry firewood, reduces heat waste, and improves the combustion efficiency of firewood. Through the provision of the heat insulation layer and the airflow layer, the heat lost from the outer wall of the kiln body can be effectively absorbed and utilized, effectively avoiding heat loss, and also playing the role of preheating air, which can improve the combustion efficiency of subsequent firewood. The utility model has the advantages of reducing heat waste, improving heat utilization, and having a good waste heat recovery effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0015] In the figure: 1-kiln body, 2-waste heat recovery chamber, 3-chimney, 4-vertical wall, 5-air inlet chamber, 6-heat exchange chamber, 7-air outlet chamber, 8-firewood stacking area, 9-heat exchange tube, 10-sealed door, 11-insulation layer, 12-air flow layer, 13-connecting pipe, 14-exhaust fan, 15-dehumidifier, 16-water-cooled wall, 17-upper ring pipe, 18-lower ring pipe, 19-vertical pipe, 20-support block, 21-heat conduction ring, 22-inclined plate. DETAILED DESCRIPTION

[0016] The present invention is further described below in conjunction with the accompanying drawings, but the present invention is not limited in any way. Any changes or improvements made based on the present invention belong to the protection scope of the present invention.

[0017] like Figure 1As shown, the utility model includes a kiln body 1, a waste heat recovery chamber 2 and a chimney 3. The kiln body 1 and the chimney 3 are both prior arts. The kiln body 1 includes a kiln head, a kiln body and a kiln tail connected in sequence. The end away from the chimney 3 is the kiln head end, and the end close to the chimney 3 is the kiln tail end. The chimney 3 is used to generate suction force to suck the outside air into the kiln body 1 and discharge the smoke. The interior of the waste heat recovery chamber 2 is divided into an air inlet chamber 5, a heat exchange chamber 6 and an air outlet chamber 7 by two vertical walls 4. The air inlet chamber 5 is connected to the kiln tail of the kiln body 1, and the top of the air outlet chamber 7 is connected to the bottom of the chimney 3. The heat exchange chamber 6 is divided into a plurality of pipes. The kiln body 1 is divided into a plurality of firewood stacking areas 8, each tube row comprises a plurality of heat exchange tubes 9 which are spaced and arranged in parallel, both ends of each heat exchange tube 9 are respectively connected with the air inlet cavity 5 and the air outlet cavity 7, a sealing door 10 is arranged on the side wall of the heat exchange cavity 6 above each tube row, a heat insulation layer 11 is arranged on the outer wall of the kiln body 1, an air flow layer 12 is formed between the heat insulation layer 11 and the outer wall of the kiln body 1, the air flow layer 12 at the kiln head end of the kiln body 1 is blocked by a blocking plate, the air flow layer 12 at the kiln tail end of the kiln body 1 is openly arranged, and the air flow layer 12 close to the blocking plate is connected with the kiln head of the kiln body 1 through a connecting pipe 13.

[0018] When the utility model is in operation, the sealing door 10 is opened, and firewood is thrown into the firewood stacking area 8 through the sealing door 10, and the firewood is stacked on the pipe row. After the stacking is completed, the sealing door 10 is closed. At the same time, pottery is fired in the kiln body 1 of the dragon kiln, and the smoke exhausted from the kiln tail of the kiln body 1 enters the air inlet cavity 5, and then enters each heat exchange tube 9, passes through the heat exchange tube 9 into the air outlet cavity 7, and is finally discharged through the chimney 3. In the above process, when the flue gas passes through the heat exchange tube 9, the heat is transferred to the firewood stacking area 8 through the wall of the heat exchange tube 9, and heat exchange occurs with the firewood to heat the firewood. The moisture in the firewood evaporates due to the heat, and the moisture content of the firewood is reduced. Finally, the purpose of drying the wood is achieved. The firewood is dried by using the waste heat of the flue gas, which has a good waste heat recovery effect, improves the combustion efficiency of the firewood, reduces the waste of heat in the flue gas, and improves the utilization rate of heat; secondly, under the suction action of the chimney 3 and the kiln body 1 itself, the outside air enters the air flow layer 12 from the tail end of the kiln body 1, and continuously flows toward the head end of the kiln body 1. During the flow process, it absorbs and takes away the heat emitted from the kiln body 1, which has a good waste heat recovery effect. On the one hand, it avoids the loss and waste of heat, and on the other hand, it can also increase the temperature of the air, which plays a role in air preheating, so that after the air enters the kiln body 1, it can effectively improve the combustion efficiency of the firewood. In summary, the utility model utilizes the waste heat of the flue gas to dry the firewood, thereby reducing the waste of heat and improving the combustion efficiency of the firewood. Through the arrangement of the heat insulation layer 11 and the airflow layer 12, the heat dissipated from the outer wall of the kiln body 1 can be effectively absorbed and utilized, which effectively avoids the loss of heat and can also play the role of preheating the air, thereby improving the combustion efficiency of the subsequent firewood.

[0019] An exhaust fan 14 is arranged on the connecting pipe 13. When the utility model is in operation, the suction force generated by the dragon kiln body 1 and the chimney 3 is used to first suck the outside air into the air flow layer 12, and then send it into the dragon kiln through the connecting pipe 13 after passing through the air flow layer 12. Compared with the general dragon kiln, since the outside air needs to enter the air flow layer 12 and the connecting pipe 13 first, and this process will undoubtedly increase the resistance of the air flow, which may cause the problem of insufficient air volume in the kiln. In order to compensate for this problem, the exhaust fan 14 is arranged to provide additional power for the outside air to enter the air flow layer 12, thereby increasing the air volume and meeting the dragon kiln's requirement for air volume when firing pottery.

[0020] A dehumidifier 15 is arranged outside the waste heat recovery chamber 2. The dehumidifier 15 is an existing device for removing moisture from the gas. The air inlet end of the dehumidifier 15 is connected to the top of the heat exchange chamber 6, and the air outlet end of the dehumidifier 15 is connected to the bottom of the heat exchange chamber 6. When the utility model is in operation, the waste heat in the flue gas is used in the waste heat recovery chamber 2 to dry the firewood, and the moisture in the firewood is evaporated. As the use process is prolonged, the moisture in the firewood is continuously evaporated, so that the moisture content in the waste heat recovery chamber 2 is getting higher and higher, which will affect the subsequent drying efficiency of the firewood. In order to avoid this situation, a dehumidifier 15 is provided to discharge hot air with high humidity from the top of the heat exchange chamber 6. After the moisture in the hot air is removed by the dehumidifier 15, the dry gas is returned to the bottom of the heat exchange chamber 6. On the one hand, the moisture in the hot air is removed to maintain a good firewood drying efficiency. On the other hand, the hot air in the heat exchange chamber 6 is kept in a continuous flow state, which can not only improve the heat dissipation efficiency of the dragon kiln flue gas in the heat exchange tube 9, but also quickly take away the moisture in the hot air, thereby improving the drying efficiency of the firewood.

[0021] A water-cooled wall 16 is arranged on the inner wall of the chimney 3. The water-cooled wall 16 is an existing structure, usually including a spiral coil, with cold water flowing inside, fixed on the inner wall of the chimney 3, and used to absorb heat in the flue gas, reduce the flue gas temperature, and reduce the waste of heat in the flue gas.

[0022] The upper and lower parts of the chimney 3 are respectively concentrically provided with an upper ring pipe 17 and a lower ring pipe 18. A plurality of vertical pipes 19 are evenly distributed in the chimney 3. The upper end of the vertical pipe 19 is connected to the upper ring pipe 17 after being bent, and the lower end of the vertical pipe 19 is connected to the lower ring pipe 18 after being bent. When the flue gas flows in the chimney 3, a cold medium is introduced into the upper ring pipe 17, the vertical pipe 19 and the lower ring pipe 18. The cold medium can absorb the heat in the flue gas and reduce the waste of heat. At the same time, the cold medium can be selected from cold water, cold air and other media, which can be used after the temperature rises to supply factory production or people's daily life. The length direction of the vertical pipe 19 is parallel to the flow direction of the flue gas to avoid resistance to the flow of the flue gas, ensure that the chimney 3 can generate sufficient suction force on the inside of the kiln body 1, and then ensure that the flame and airflow generated by the burning of firewood can flow smoothly in the kiln body 1.

[0023] A plurality of support blocks 20 are provided between the heat insulating layer 11 and the outer wall of the kiln body 1. The support blocks 20 are located between the heat insulating layer 11 and the outer wall of the kiln body 1 and have the following functions: first, they support the heat insulating layer 11 to prevent the heat insulating layer 11 from being deformed and to improve the stability of the heat insulating layer 11; second, when the airflow flows in the airflow layer 12, the direction of the airflow will be changed when it flows through the support blocks 20, thereby making the airflow more evenly distributed in the airflow layer 12, preventing the formation of stagnation areas and improving the heat absorption effect of the airflow.

[0024] A plurality of heat-conducting rings 21 are evenly spaced along the length of the outer wall of the heat exchange tube 9. The heat-conducting rings 21 are made of a material with high thermal conductivity, which can increase the heat dissipation surface area of ​​the heat exchange tube 9, improve the heat dissipation efficiency of the flue gas, and further improve the drying efficiency of the firewood and the heat recovery effect.

[0025] An inclined plate 22 is provided in the air outlet cavity 7. When the utility model is in operation, the smoke generated when the dragon kiln is firing pottery is sent from the kiln tail of the kiln body 1 into the air inlet cavity 5, and passes into the air outlet cavity 7 through the heat exchange tube 9. Since the smoke has a fast flow rate when flowing out of the heat exchange tube 9, and the smoke contains a large amount of impurities such as wood ash, as the use time increases, it may damage the wall of the waste heat recovery chamber 2, causing smoke leakage, and also affecting the normal operation of the dragon kiln. In order to solve this problem, an inclined plate 22 is provided. When the smoke rushes out of the heat exchange tube 9, it no longer impacts the side wall of the waste heat recovery chamber 2, but impacts the inclined plate 22. The inclined plate 22 is made of wear-resistant and impact-resistant material and has the following functions: first, it blocks the impact of flue gas on the side wall of the waste heat recovery chamber 2, thereby extending the service life of the waste heat recovery chamber 2 and replacing the inclined plate 22 in time when it is damaged; second, it is dust removal. When impurities such as wood ash in the flue gas impact the inclined plate 22, the impurities such as wood ash are separated from the flue gas, thereby reducing the dust content in the flue gas and requiring regular cleaning; third, it is guiding. It guides the flue gas to smoothly pass into the chimney 3 upward, thereby reducing the irregular turbulence generated by the flue gas in the air outlet cavity 7, thereby reducing the resistance during the flue gas emission process.

Claims

1. A dragon kiln flue gas waste heat recovery device, comprising a kiln body (1), a waste heat recovery chamber (2) and a chimney (3), characterized in that The interior of the waste heat recovery chamber (2) is divided into an air inlet chamber (5), a heat exchange chamber (6) and an air outlet chamber (7) by two vertical walls (4); the air inlet chamber (5) is connected to the kiln tail of the kiln body (1); the top of the air outlet chamber (7) is connected to the bottom of the chimney (3); the heat exchange chamber (6) is divided into a plurality of firewood stacking areas (8) by a plurality of pipe rows; each pipe row includes a plurality of heat exchange tubes (9) that are spaced and arranged in parallel; and both ends of each heat exchange tube (9) are respectively connected to the air inlet chamber (5) and the air outlet chamber ( 7), a sealing door (10) is arranged on the side wall of the heat exchange cavity (6) above each tube row, a heat insulation layer (11) is arranged on the outer wall of the kiln body (1), an air flow layer (12) is formed between the heat insulation layer (11) and the outer wall of the kiln body (1), the air flow layer (12) located at the kiln head end of the kiln body (1) is blocked by a blocking plate, and the air flow layer (12) located at the kiln tail end of the kiln body (1) is openly arranged, and the air flow layer (12) close to the blocking plate is connected to the kiln head of the kiln body (1) through a connecting pipe (13).

2. The dragon kiln flue gas waste heat recovery device according to claim 1 is characterized in that The connecting pipe (13) is provided with an exhaust fan (14).

3. The dragon kiln flue gas waste heat recovery device according to claim 1 is characterized in that A dehumidifier (15) is arranged outside the waste heat recovery chamber (2), the air inlet end of the dehumidifier (15) is connected to the top of the heat exchange chamber (6), and the air outlet end of the dehumidifier (15) is connected to the bottom of the heat exchange chamber (6).

4. The dragon kiln flue gas waste heat recovery device according to claim 1 is characterized in that A water-cooled wall (16) is provided on the inner wall of the chimney (3).

5. The dragon kiln flue gas waste heat recovery device according to claim 1 is characterized in that An upper ring tube (17) and a lower ring tube (18) are concentrically arranged at the upper and lower parts of the chimney (3), respectively. A plurality of vertical tubes (19) are evenly distributed in the chimney (3). The upper ends of the vertical tubes (19) are bent and connected to the upper ring tube (17), and the lower ends of the vertical tubes (19) are bent and connected to the lower ring tube (18).

6. The dragon kiln flue gas waste heat recovery device according to claim 1 is characterized in that A plurality of support blocks (20) are arranged between the heat insulation layer (11) and the outer wall of the kiln body (1).

7. The device for recovering waste heat from flue gas from a dragon kiln according to claim 1, characterized in that A plurality of heat-conducting rings (21) are evenly spaced on the outer wall of the heat exchange tube (9) along its length.

8. The dragon kiln flue gas waste heat recovery device according to claim 1, characterized in that An inclined plate (22) is provided in the air outlet cavity (7).

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