CN110595205A - An energy-saving and high-efficiency tunnel kiln for firing multi-layer foamed ceramics - Google Patents

Abstract

The embodiment of the present invention discloses an energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics, which includes a kiln body composed of a kiln body frame and a refractory insulation layer. The kiln body includes a heating section (including a smoke exhaust area) section, preheating section and high-temperature firing section); the smoke exhaust section is provided with a smoke exhaust system, a top flue located at the top of the kiln main body and a kiln wall flue located in the kiln walls on both sides. The smoke inlet of the kiln wall flue is located in the lower part of the kiln, and both the top flue and the kiln wall flue are connected to the smoke exhaust system for simultaneously extracting the flue gas from the top and bottom of the kiln cavity; the preheating The section and the high-temperature firing section are equipped with a combustion system and a combustion-supporting system. The present invention realizes simultaneous firing of multi-layer foamed ceramics through the cooperation of the smoke exhaust section, the preheating section and the high-temperature firing section, thereby saving energy and improving production efficiency.

Description

An energy-saving and high-efficiency tunnel kiln for firing multi-layer foamed ceramics

technical field

The invention relates to a high-temperature kiln, in particular to an energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics.

Background technique

Foamed ceramic materials are sintered at high temperature from raw materials such as industrial waste (such as tile polishing waste, cinder, steel slag, etc.), low-quality clay (such as silt, shale, etc.) and inorganic foaming agents (such as silicon carbide powder). Energy-saving and environmentally friendly materials, with excellent thermal insulation, high temperature resistance, good sound insulation, etc., mainly used in building walls (inner partition wall or external insulation), metallurgical industry insulation, subway station noise reduction, automobile exhaust filtration and other industries. The porous structure is formed by high-temperature foaming to achieve the required performance of thermal insulation, sound attenuation, and filtration. In recent years, with the promotion of green building materials and prefabricated buildings by the Ministry of Housing and Urban-Rural Development, a large-area (such as 1200mm*2400mm) foamed ceramic partition board has quietly emerged. However, constrained by factors such as high energy consumption, small output, and low pass rate in the firing process, foamed ceramics have encountered technical bottlenecks in the industrialization process. Ceramic companies urgently need a technology and equipment that is energy-saving, efficient, large-scale, and iteratively upgraded. , to reduce process loss, reduce costs, and enhance profitability.

There are roughly two types of continuous firing kilns:

One is a roller kiln. The raw material powder is distributed on the refractory backing plate covered with ceramic paper, and there are material retaining blocks around it. The refractory backing plate and the powder are transported through the rollers. The powder is melted and evaporated at high temperature. After soaking and cooling, a porous ceramic plate is formed. However, because the roller rod is supported by two points outside the kiln, the bearing capacity is small, so its inner width is generally within 2.5m, and only a single layer can be loaded, and the product thickness is within 100mm, so the output is low. At present, the maximum daily output of a single kiln is Between 60m ³ product and 80m ³ product, or even less, the natural gas consumption per unit product is about 150m ³ natural gas/m ³ product.

The other is a tunnel kiln, in which the refractory backing plate is laid flat on the silicon carbide beam of the kiln car, ceramic paper is set, powder is arranged, and the kiln runs through the kiln car. The powder is melted, foamed and cooled at high temperature to form a porous Ceramic plates. Compared with the suspended rollers, the kiln car runs on the track, and its bearing capacity is greatly increased. The inner width can be 3m~6m, and the product thickness can be 100mm~300mm. However, the existing tunnel kiln is generally loaded with a single layer, and its daily output is only about 120m ³ products, and the natural gas consumption per unit product is about 120m ³ natural gas/m ³ products.

It can be known from the above situation that although foamed ceramics are a product of "turning waste into treasure" and have obvious advantages, tunnel kilns have improved compared with roller kilns in terms of output and unit fuel consumption, but the overall cost (energy cost accounts for 40% of the total cost) %) is still higher than existing products, such as building blocks for partition walls, prefabricated partition boards, gypsum keels and glass bricks, etc., so it is still difficult to meet ceramic enterprises and market demand, resulting in difficulties in promotion.

Contents of the invention

The technical problem to be solved by the embodiments of the present invention is to provide an energy-saving and high-efficiency tunnel kiln for firing multi-layer foamed ceramics, which can realize simultaneous firing of multi-layer foamed ceramics, save energy and improve production efficiency.

In order to solve the above technical problems, an embodiment of the present invention provides an energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics, which includes a kiln body composed of a kiln body frame and a refractory insulation layer. The kiln body includes a smoke exhaust section and high temperature firing section;

The smoke exhaust section is provided with a smoke exhaust system, a top flue located at the top of the kiln main body, and kiln wall flues located in the kiln walls on both sides. The smoke inlet of the kiln wall flue is located at the lower part of the kiln. Both the top flue and the kiln wall flue are connected to the smoke exhaust system for simultaneously extracting the flue gas from the top and bottom of the kiln cavity;

The high-temperature firing section is provided with a combustion system and a combustion-supporting system. The combustion system includes a gas main pipe, a gas drop branch pipe, a vertical gas branch pipe, and more than three rows of burners at different heights. The same row of burners is supplied by the same vertical gas branch pipe, and the vertical gas branch pipe is connected to the gas main pipe through the corresponding gas drop branch pipe; the combustion support system includes a combustion support main pipe, a combustion support drop branch pipe and a vertical combustion support branch pipe The combustion-supporting drop pipe is connected with the combustion-supporting main pipe to supply combustion-supporting air to each burner.

As an improvement to the above scheme, a preheating section is also provided between the smoke exhaust section and the high-temperature firing section, and preheating burners are provided at the kiln walls on both sides of the preheating section corresponding to the bottom fire channel , the preheating burner cross-sprays from the fire channel, and heats the products of other layers through the hot gas escape.

As an improvement of the above solution, the top flues are arranged in a row on the top of the kiln main body.

As an improvement of the above solution, the smoke exhaust system includes a smoke exhaust fan, a smoke exhaust main pipe, an external chimney, a top smoke exhaust downpipe and a top smoke exhaust horizontal pipe, the smoke exhaust fan is arranged on the smoke exhaust main pipe, the Outer exhaust chimney, exhaust main pipe, top exhaust downpipe and top exhaust horizontal pipe are connected sequentially, and the top exhaust horizontal pipe is connected with the outer chimney; the kiln wall flue is connected to all The above-mentioned smoke exhaust main connection.

As an improvement of the above scheme, it also includes a kiln car adapted to it, the kiln car includes a base, wheels are provided on the base, and a kiln car refractory insulation layer is provided on the top surface;

The base is also provided with a support column, and a loading frame is provided on the support column, and the loading frame includes a main beam fixed on the support column horizontally, a support beam vertically installed on the main beam, and a splicing frame located on the support beam. It is a refractory backing plate used for loading products, and the loading frame is provided with multi-layer refractory backing plates.

As an improvement of the above solution, the refractory insulation layer includes a bottom refractory insulation layer located at the bottom of the kiln, and the inner side of both sides of the bottom refractory insulation layer is provided with concave-convex structures, which cooperate with the concave-convex structures on both sides of the kiln car to form a sealed kiln bottom.

As an improvement of the above solution, the total width of the assembled refractory backing plate is greater than the width of the refractory insulation layer of the kiln car.

As an improvement of the above scheme, in the same combustion module, the lowest row of burners is marked as the bottom burner, the highest row of burners is the top burner, and several rows of burners between the bottom burner and the top burner are the middle burner. Nozzles, wherein the top layer burners, the middle layer burners and the bottom layer burners are arranged alternately in the horizontal direction and the vertical direction.

As an improvement of the above scheme, the top layer burner corresponds to heating the space above the product on the uppermost backing plate, and the middle layer burner corresponds to heating the space between the bottom of the middle upper backing plate and the product on the middle lower backing plate. The bottom burner corresponds to heating the space below the lowermost refractory backing plate.

As an improvement of the above scheme, the number of burners in each row of the bottom layer is twice that of the top layer of burners in each row.

Implementing the embodiment of the present invention has the following beneficial effects:

The present invention can reduce the temperature of exhausted exhaust gas by setting a preheating section and a smoke exhaust section before the high temperature firing section, and prolong the service life of a smoke exhaust pipe and a fan. Using high-temperature flue gas to preheat raw materials can make full use of the heat energy of exhaust gas and save energy. In addition, the raw materials are preheated step by step through the smoke exhaust section and the preheating section, and the raw materials are heated up according to the predetermined temperature curve, so as to avoid direct contact of the raw materials with the flames ejected from the burner in the low temperature state, and the excessive temperature rise will cause product defects.

In the present invention, the specially designed kiln car cooperates with the high-temperature firing section of the kiln to realize simultaneous firing of multi-layer foamed ceramics, save energy and improve production efficiency.

Description of drawings

Fig. 1 is the overall structure schematic diagram of the energy-saving high-efficiency tunnel kiln of a kind of multi-layer foamed ceramic firing of the present invention;

Fig. 2 is a side view of the smoke exhaust section of the tunnel kiln of the present invention;

Fig. 3 is the top view of the smoke exhaust section of the tunnel kiln of the present invention;

Fig. 4 is the cross-sectional view of the smoke exhaust section of the tunnel kiln of the present invention;

Fig. 5 is an enlarged view of part A of Fig. 4;

Fig. 6 is the structural representation of kiln car of the present invention;

Fig. 7 is a schematic structural view of the high-temperature firing section of the tunnel kiln of the present invention;

Fig. 8 is an enlarged view of part A of Fig. 7;

Figure 9 and Figure 10 are cross-sectional views of different longitudinal positions of the high-temperature firing zone of the tunnel kiln of the present invention;

Fig. 11 is a schematic structural view of the quenching section of the tunnel kiln of the present invention;

Fig. 12 is a schematic structural view of the slow cooling section of the tunnel kiln of the present invention;

Fig. 13 is a schematic structural view of the tail cooling section of the tunnel kiln of the present invention;

14-16 are cross-sectional views of different longitudinal positions of the tail cooling section of the tunnel kiln of the present invention.

Detailed ways

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below in conjunction with the accompanying drawings. In this application, the longitudinal direction along the kiln length is the longitudinal direction, the kiln width direction is the horizontal direction, the vertical or vertical direction is the height space direction, the two sides refer to both sides of the kiln, and the cross section refers to the width direction inside the kiln.

As shown in FIG. 1 , the specific embodiment of the present invention provides an energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics, which includes a kiln body 1 composed of a kiln body frame 11 and a refractory insulation layer 12 . The roof of the kiln is made of cordierite-mullite slab + light insulation cotton (specific gravity 0.128g/cm ³ ), and the kiln wall is made of lightweight refractory brick (specific gravity 0.8g/cm ³ ) + lightweight cotton board (specific gravity less than 0.3 g/cm ³ ) structure and kiln car refractory layer are mainly made of lightweight thermal insulation cotton, so that it has good thermal insulation and sealing effects, small heat dissipation and high energy-saving benefits. In order to realize different functions, the kiln main body 1 is divided into different sections, and the shapes and supporting equipment of the kiln main body 1 in different sections are different. Specifically, the kiln body 1 includes a smoke exhaust section 2, a high-temperature firing section 4, and a cooling section; the smoke exhaust section 2 is used to discharge the flue gas generated by the high-temperature firing section 4, and the The high-temperature firing section 4 is used to raise the temperature of the blank of the foamed ceramics to make it foam and sinter, and the cooling section is used to cool the foamed ceramics.

2-5, the smoke exhaust section 2 is provided with a smoke exhaust system, a top flue 21 located at the top of the kiln body 1 and a kiln wall flue 22 located in the kiln walls on both sides. The smoke inlet 221 of the kiln wall flue 22 is located at the lower part of the kiln, and the top flue 21 and the kiln wall flue 22 are both connected to the smoke exhaust system, and are used to simultaneously discharge the flue gas from the top and bottom of the kiln cavity. Extraction; the smoke exhaust system includes a smoke exhaust fan 23, a smoke exhaust main pipe 24, an outer chimney 25, a top smoke exhaust drop pipe 26 and a top smoke exhaust horizontal pipe 27, and the smoke exhaust fan 23 is arranged on the smoke exhaust main pipe 24 , the outer chimney 25 , main exhaust pipe 24 , top exhaust downpipe 26 and top exhaust horizontal pipe 27 are sequentially connected, and the top smoke exhaust horizontal pipe 27 is connected with the top flue 21 . The kiln wall flue 22 is connected with the smoke exhaust main pipe 24 through a side exhaust branch pipe 28 . Through the contact between the high-temperature flue gas and the foamed ceramic blank, the mechanical water and adsorbed water in the raw material are removed, and the blank does not undergo chemical changes, but only physical changes such as volume shrinkage and water evaporation. In order to reduce the temperature difference in the cross-section and vertical height direction, the combination of top pumping and bottom pumping on both sides is adopted. The top flue 21 is arranged in a row on the top of the kiln main body 1, and the flue gas volume is adjusted through the valve 29. , to change the size and flow direction of the same cross-sectional airflow, and reduce the cross-sectional temperature difference by stirring and splitting. Bottom pumping on both sides is convenient for pulling down the flue gas accumulated on the top of the kiln. The temperature of the lower part is raised during the flow of the flue gas, which meets the needs of heating up multi-layer materials and reduces the temperature difference between the upper and lower sides of the kiln.

Preferably, a preheating section 3 may also be provided between the smoke exhaust section 2 and the high-temperature firing section 4, and in this section, the temperature rises from 600°C to about 1050°C. The preheating section 3 is provided with an independent combustion system (not shown in the figure), which cooperates with the high-temperature flue gas discharged from the high-temperature firing section 4 to preheat the foamed ceramic blank. Specifically, it is heated in the bottom flue (the channel formed between the kiln car surface and the bottom refractory backing plate), and the burners on both sides of the kiln wall are sprayed from between the flue, and the hot gas can heat other layers after escaping. product. In this section, the main chemical changes of raw materials are the elimination of crystal water, the decomposition and oxidation of organic matter, carbonates, sulfates and other compounds contained in raw materials, and the transformation of quartz crystal form. By arranging the preheating section 3 and the smoke exhaust section 2 before the high temperature firing section 4, the temperature of the exhausted exhaust gas can be reduced, and the service life of the smoke exhaust pipe and the fan can be prolonged. Using high-temperature flue gas to preheat raw materials can make full use of the heat energy of exhaust gas and save energy. In addition, the raw materials are preheated step by step through the smoke exhaust section 2 and the preheating section 3, and the raw materials are heated up according to the predetermined temperature curve, so as to avoid the direct contact of the raw materials with the flames ejected from the burner in the low temperature state, and the rapid temperature rise will cause product defects .

The high-temperature firing section 4 is provided with a combustion system and a combustion-supporting system for raising the temperature from 1050°C to the highest firing temperature (foamed ceramics are generally around 1150°C). The combustion system includes a gas main pipe 41, a gas drop branch pipe 42, a vertical gas branch pipe 43, and more than three rows of burners 44 at different heights. The same row of burners 44 in each combustion module is supplied by the same vertical gas branch pipe 43. gas, the vertical gas branch pipe 43 is connected with the gas main pipe 41 through the corresponding gas drop branch pipe 42; 46 is connected with combustion-supporting main pipe 45 (do not draw the flexible pipe that burner 44 is connected with vertical combustion-supporting sub-pipe 47 among the figure), supply combustion-supporting air for each burner 44.

Referring to Fig. 6, in order to fire multi-layer foamed ceramics at one time, the kiln furnace of the present invention also includes a kiln car 5 adapted thereto. Described kiln car 5 comprises base 51, and described base 51 is provided with wheel 52, and the top surface of base 51 is provided with kiln car refractory insulation layer 53; Described base 51 is also provided with support column 54, and described support column 54 A loading frame is arranged on the top, and the loading frame includes a main beam 55 fixed horizontally on the support column 54, a support beam 58 vertically installed on the main beam 55, and a refractory mat supported on the main beam 55 and divided into at least two layers. plate 56. Multiple pieces of the refractory backing plates 56 are spliced on the support beams 58 to form a bearing plate surface. When charging, if a 1200mm*2400mm foamed ceramic plate is produced, a space of 1200mm*2400mm is formed around the refractory backing plate 56 through the block 57, and a whole piece of ceramic paper with a thickness of about 2mm is laid inside (can withstand about 1200°C temperature), prevent material from leaking between the spliced refractory backing plates 56, and avoid adhesion and damage to the refractory backing plate 56 and the material blocking block 57 after high-temperature melting. In this embodiment, the kiln car 5 is loaded with three layers of products, the top fire channel is formed between the kiln roof and the upper product, the middle fire channel is formed between the refractory backing plate 56 for loading the product and its lower product, and the kiln car is refractory and heat-preserved. A bottom fire channel is formed between the layer 53 and the lowermost refractory backing plate 56 loaded with products. 4 rows of burners 44 are distributed in the horizontal direction of the kiln, and the top fire channel, the middle fire channel, and the bottom fire channel are respectively provided with combustion groups, and the middle two rows of burners 44 are the same combustion group, so as to control the temperature difference between the upper and lower sides of each layer of products. Make the product quality stable.

Further, referring to Fig. 7-Fig. 10, the high-temperature firing section 4 is composed of a plurality of combustion modules with the same structure. In the same combustion module, the lowest row of burners 44 is marked as the bottom burner 44a, the highest row of burners 44 is the top burner 44c, and several rows of burners 44 between the bottom burner 44a and the top burner 44c are the middle layer The burners 44b, wherein, the top layer burners 44c, the middle layer burners 44b and the bottom layer burners 44a are arranged staggered in the horizontal direction and the vertical direction. The top burner 44c corresponds to heating the upper space of the product on the uppermost refractory backing plate, and the middle layer burner 44b corresponds to heating the space between the bottom of the middle upper backing plate and the product on the middle lower backing plate. The nozzle 44a corresponds to heating the space below the lowermost refractory backing plate. When the temperature rises, the flames are sprayed from the burners 44 on both sides of the fire channel, and transfer heat to the product through radiation, convection and conduction. By setting multi-layer burners 44 on each side, the temperature of each layer is controlled by thermocouples 48, solenoid valves 49, electric valves 40, temperature control meters and other components, so as to solve the problem of temperature difference between different layers of products and make each layer of products The holes are uniform and the quality is stable. The solenoid valve 49 is turned on when it is powered on, and it is automatically turned off when it is powered off. When it encounters a sudden power failure, it can automatically cut off the gas source and play a role in safety protection. The electric valve is used to automatically adjust the opening of the gas supply pipe according to the temperature change, so as to control the air pressure of the burner 44 .

This application adopts the kiln body and kiln car structure of lightweight refractory insulation cotton to reduce heat dissipation; use energy-saving isothermal high-speed burners for heating; recover and utilize the waste heat in the cooling area to increase the temperature of the combustion-supporting air and other energy-saving technologies; optimize the loading method, such as thinning Refractory backing plate (such as reduced from 10mm to 8mm) and reduce the weight of the block, increase the thickness of each layer of products fired, increase the heat utilization rate by increasing the weight ratio of the product in the kiln furniture, etc. After the number of loading layers increases, the daily output of a single kiln can reach more than 250m ³ products. Due to energy-saving technology and optimized loading structure, the natural gas consumption per unit product can be controlled within 80m ³ natural gas/m ³ products, achieving large production capacity and low fuel consumption , The purpose of high pass rate solves the existing problems.

Preferably, the number of bottom burners 44a in each row is twice that of top burners 44c in each row. As the hot air rises, the temperature of the upper raw materials rises faster. Therefore, by increasing the number of bottom burners 44a, the heating speed of the raw materials at the lower layer and the raw materials at the upper layer can be approached, reducing the difficulty of temperature control and improving product quality.

In this section, the change of the raw material is that the feldspar flux in the green body melts to appear a liquid phase, forming a silicate eutectic. Due to the existence of the foaming agent, the gas volume expands at high temperature and escapes to form holes. Under the action of the surface tension of the eutectic, not only the particles are rearranged tightly, but also the thin walls between the holes are cemented to each other, and formed after cooling down. Closed-cell ceramic plates. The porous shape also increases the volume and decreases the density of this ceramic, so as to achieve the effects of heat preservation, sound insulation and heat insulation.

The kiln car 5 is not only used for loading and transporting products, but the refractory insulation layer 53 of the kiln car also plays the role of sealing the bottom of the kiln. The refractory insulation layer 12 includes a bottom refractory insulation layer 12a located at the bottom of the kiln. The inner sides of the bottom refractory insulation layer 121 are provided with concave-convex structures 122, which cooperate with the convex-concave structures 531 on both sides of the kiln car 5 to form a sealed kiln bottom. A sand sealing mechanism 13 is also provided between the kiln car 5 and the kiln main body 1 . Through the staggered fit of the protruding part 122 and the fitting part 531, most of the hot gas can be blocked, preventing the heat from being transmitted to the bottom of the kiln. The sand sealing mechanism 13 located under the protruding portion 122 and the fitting portion 531 realizes further sealing of the flue gas and further prevents leakage of hot gas.

Preferably, the top surface of the bottom refractory insulation layer 121 is higher than the top surface of the kiln car refractory insulation layer 53 . The total width of the assembled refractory backing plate 56 is greater than the width of the refractory insulation layer 53 of the kiln car. In the event of an accident such as the collapse of the kiln car 5, the refractory backing plate 56 on the kiln car 5 will be supported on the bottom refractory insulation layer 121, so that it will not completely fall over and get stuck in the kiln, so that the subsequent kiln car 5 will replace the refractory backing plate 56 And the foam ceramics on the refractory backing plate 56 is released.

After the sintering of the foamed ceramics is completed, it enters the cooling section, and the cooling section includes a rapid cooling section 6 , a slow cooling section 7 and a tail cooling section 8 .

As shown in Figure 11, the rapid cooling section quickly cools the product from the highest firing temperature to about 600°C to complete the rapid cooling. The quenching section 6 is provided with a quenching fan (not shown in the figure), a quenching air duct 62 and a quenching air duct 61, and the quenching air duct 61 is arranged in the two side walls of the kiln main body 1, and the quenching fan 61 is connected with the quenching air channel 61 through the quenching air duct 62; the quenching air channel 61 is facing the fire channel between the bottom fire channel, the top fire channel and the product, and the cold wind is sprayed out from the rapid cooling air channel 61, so that each layer The product is cooled evenly. The main function of the quenching section 6 is rapid cooling. At this stage, the viscosity of the glass phase in the product increases, and it transforms from a plastic state to a solid state, and the hardness and strength increase to the maximum. Due to the existence of the liquid phase, it can offset the stress caused by the shrinkage of the product, so it can be directly blown and quickly cooled, which is also a key area for ceramic production to shorten the firing cycle.

As shown in Figure 12, the slow cooling section 7 slowly cools the product temperature from 600°C to about 350°C. It includes a refrigerant supply system and a heat exchange pipe 71 located in the kiln body 1, the refrigerant supply system is connected to the heat exchange pipe 71, and the refrigerant is introduced into the heat exchange pipe 71; the refrigerant supply system includes a refrigerant supply pipe 72 and Refrigerant driving device (not shown in the figure), said refrigerant includes any one of air, water or oil. In this embodiment, air is used as the refrigerant, and the outside air automatically enters the negative-pressure heat exchange tube 71, and the air is drawn out from the other end of the heat exchange tube 71 by a fan. Exchange to cool down. The heat exchange tubes 71 are arranged longitudinally in the kiln so as to ensure consistent cooling rates of products at different heights in the kiln. The main function of the slow cooling zone is to cool slowly, to eliminate the internal and external stress of the product caused by rapid cooling, and to prevent cracking. Generally, indirect cooling is used. At this stage, the crystal transformation of quartz occurs (573°C). Although there is only 0.82% volume shrinkage, because the transformation time is only a few minutes, it must be cooled slowly, otherwise there will be "cold cracking" defects, which will reduce the firing rate. .

13-16, the tail cooling section 8 includes a tail cooling fan (not shown in the figure), a tail cooling air pipe 82, a tail cooling exhaust pipe 83 and a tail cooling exhaust fan (not shown in the figure), The tail cooling fan is connected to the tail cooling air outlet 81 through the tail cooling air pipe 82 ; the tail cooling air outlet 81 is arranged in the side wall of the kiln main body 1 . Preferably, the tail cooling air outlets 81 are arranged alternately on both side walls of the kiln main body 1 . The tail cooling air duct 83 is connected to the top tail cooling air outlet 85 and the side tail cooling air outlet 86; the top tail cooling air outlet 85 is arranged on the top wall of the kiln main body 1 . Preferably, the top tail cooling air outlet 85 is connected to two air exhaust hoods 84 provided on the top wall of the kiln main body 1 . The side tail cooling air outlets 86 are arranged symmetrically on both side walls of the kiln main body 1 . The main function of the tail cooling zone is final cooling, which lowers the product to a temperature that can be manually or mechanically discharged from the kiln. The same row adopts 2 exhaust hoods with 84 top exhausts, and the two side walls use multiple exhaust pipes to align with the fire channel and draw symmetrically. Each exhaust port adjusts the air volume through a valve; The quasi-firing channels are blown alternately to reduce the temperature difference in the kiln and prevent the product from cracking or deforming.

The firing cycle ratio of conventional ceramic products is generally more than 60% for firing and less than 40% for cooling. The invention is designed according to the characteristics of the product process, that is, the product is made of powder melted and then foamed. After entering the kiln, there is no need to worry about cracking, and the temperature can be raised quickly. The internal rise to the highest firing temperature difference to shorten the firing process; but this product has good thermal insulation performance, it is difficult to release the internal heat after cooling down, the internal and external temperature difference is large, and it is easy to crack if it is not well controlled. Therefore, this application increases the length ratio of the cooling zone. To more than 60% of the overall kiln length (conventional ceramic cooling accounts for less than 40%), to shorten the firing cycle as much as possible and increase output.

The above description is a preferred embodiment of the present invention, it should be pointed out that for those skilled in the art, without departing from the principle of the present invention, some improvements and modifications can also be made, and these improvements and modifications are also considered Be the protection scope of the present invention.

Claims (10)

1. An energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics, characterized in that it comprises a kiln main body composed of a kiln body frame and a refractory insulation layer, and the kiln main body includes a smoke exhaust section and a high-temperature firing section; The smoke exhaust section is provided with a smoke exhaust system, a top flue located at the top of the kiln main body, and kiln wall flues located in the kiln walls on both sides. The smoke inlet of the kiln wall flue is located at the lower part of the kiln. Both the top flue and the kiln wall flue are connected to the smoke exhaust system for simultaneously extracting the flue gas from the top and bottom of the kiln cavity; The high-temperature firing section is provided with a combustion system and a combustion-supporting system. The combustion system includes a gas main pipe, a gas drop branch pipe, a vertical gas branch pipe, and more than three rows of burners at different heights. The same row of burners is supplied by the same vertical gas branch pipe, and the vertical gas branch pipe is connected to the gas main pipe through the corresponding gas drop branch pipe; the combustion support system includes a combustion support main pipe, a combustion support drop branch pipe and a vertical combustion support branch pipe The combustion-supporting drop pipe is connected with the combustion-supporting main pipe to supply combustion-supporting air to each burner. 2. The energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics as claimed in claim 1, wherein a preheating section is also provided between the smoke exhaust section and the high-temperature firing section, and the The kiln walls on both sides of the preheating section are equipped with preheating burners corresponding to the bottom fire passages, and the preheating burners cross-spray from between the fire passages to heat products in other layers through the upward escape of hot gas. 3. The energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics according to claim 1, wherein the top flues are arranged in rows on the top of the kiln main body. 4. The energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics as claimed in claim 2, wherein the smoke exhaust system comprises a smoke exhaust fan, a smoke exhaust main pipe, an outer chimney, a top smoke exhaust downpipe and The top smoke exhaust horizontal pipe, the smoke exhaust fan is arranged on the smoke exhaust main pipe, the outer chimney, the smoke exhaust main pipe, the top smoke exhaust drop pipe and the top smoke exhaust horizontal pipe are connected in sequence, and the top smoke exhaust horizontal pipe is connected with the The outer chimney is connected; the kiln wall flue is connected with the main smoke exhaust pipe through a side exhaust branch pipe. 5. The energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics according to claim 1, characterized in that it also includes a kiln car adapted thereto, the kiln car includes a base, and the base is provided with wheels , the kiln car refractory insulation layer is provided on the top surface; The base is also provided with a support column, and a loading frame is provided on the support column, and the loading frame includes a main beam fixed on the support column horizontally, a support beam vertically installed on the main beam, and a splicing frame located on the support beam. It is a refractory backing plate used for loading products, and the loading frame is provided with multi-layer refractory backing plates. 6. The energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics as claimed in claim 5, wherein the fire-resistant and heat-insulating layer comprises a bottom fire-resistant and heat-insulating layer positioned at the bottom of the kiln, and the inside of both sides of the bottom refractory and heat-insulating layer There is a concave-convex structure, which cooperates with the convex-concave structures on both sides of the kiln car to form a sealed kiln bottom. 7. The energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics according to claim 6, wherein the total width of the assembled refractory backing plates is greater than the width of the refractory insulation layer of the kiln car. 8. The energy-saving and high-efficiency tunnel kiln for firing multilayer foamed ceramics as claimed in claim 1, characterized in that, in the same combustion module, the lowest row of burners is marked as the bottom burner, and the highest row of burners is the top burner. The nozzles, the rows of burners located between the bottom burners and the top burners are the middle burners, wherein the top burners, middle burners and bottom burners are arranged alternately in the horizontal and vertical directions. 9. The energy-saving and high-efficiency tunnel kiln for firing multi-layer foamed ceramics as claimed in claim 8, wherein the top burner corresponds to heating the space above the product on the uppermost backing plate, and the middle burner corresponds to heating The space between the bottom of the middle upper backing plate and the product loaded on the middle lower backing plate is heated, and the bottom burner corresponds to heating the space under the lowermost refractory backing plate. 10. The energy-saving and high-efficiency tunnel kiln for firing multi-layer foamed ceramics according to claim 9, wherein the number of burners in each row of bottom layers is twice that of each row of top layer burners.