Drying device and cement kiln waste heat utilization system

Abstract

The utility model relates to the technical field of energy -conserving and carbon reduction discloses a kind of drying device and cement kiln waste heat utilization system. The drying device includes shell and material turning mechanism. Shell is internally structured with drying chamber;Shell is structured with waste heat import and exhaust port;Waste heat import is used for the waste heat of cement production line to enter;Exhaust port is used to connect with the cooling machine in cement production line;Material turning mechanism includes harrow frame and material turning driving part;Harrow frame is located in the drying chamber, material turning driving part is connected with the harrow frame, for driving harrow frame reciprocating motion along the axial direction of shell, to carry out material turning. In the utility model, not only can reduce the energy consumption and operating cost of drying process, realizes the recycling of waste heat generated by cement production line;And also increase the contact area and contact time of fuel and hot air, to strengthen the heat and mass transfer efficiency, realize the fast, uniform drying effect, solve the problem of low efficiency, uneven drying of traditional dryer.

Description

Technical Field

[0001] This utility model relates to the field of energy conservation and carbon reduction technology, and in particular to a drying device and a cement kiln waste heat utilization system. Background Technology

[0002] Currently used alternative fuels (such as municipal solid waste and sewage sludge) generally have characteristics such as high moisture content, low calorific value, and large fluctuations in composition. If they are directly and massively introduced into cement kiln systems, they can easily have an adverse effect on kiln stability and clinker quality. Therefore, it is necessary to conduct targeted pretreatment of alternative fuels according to the specific requirements of cement production processes.

[0003] Reducing the moisture content and increasing the calorific value of alternative fuels are key pathways to improving the co-processing capacity and fuel substitution rate of cement kilns, and the main technical means to achieve this goal is the drying process. Regarding existing drying equipment, traditional horizontal rotary dryers suffer from slow drying speeds, large equipment size, and low unit capacity, making it difficult to meet the high-efficiency drying requirements of large-scale alternative fuels. While grate dryers offer higher drying efficiency, their complex internal material turning structure makes maintenance and repair difficult, hindering long-term stable operation. Utility Model Content

[0004] This utility model provides a drying device and a cement kiln waste heat utilization system to solve at least one of the problems existing in the prior art, thereby achieving the drying of fuel with high moisture content and the utilization of waste heat generated by the cement production line.

[0005] The first aspect of this utility model provides a drying device, comprising: The outer shell has an internal drying chamber; the outer shell has a waste heat inlet and an exhaust vent that communicate with the drying chamber; the waste heat inlet is used to supply waste heat from the cement production line; the exhaust vent is used to connect to a cooler in the cement production line. The material turning mechanism includes a rake frame and a material turning drive; the rake frame is located in the drying chamber, and the material turning drive is connected to the rake frame to drive the rake frame to reciprocate along the axial direction of the outer shell for material turning.

[0006] According to the drying device provided by this utility model, the rake frame includes: The connecting shaft has one end connected to the material turning drive and the other end extending along the axial direction of the outer shell; Multiple rake blades are mounted at axial intervals along the connecting shaft of the housing.

[0007] According to the drying device provided by this utility model, the rake blade has a through hole along the axial direction of the outer shell.

[0008] According to the drying device provided by this utility model, the material turning drive includes one of a linear motor, a cylinder, or a hydraulic cylinder.

[0009] The drying apparatus provided by this utility model further includes: The drying air chamber and the drying air collection box are provided. The air inlet of the drying air collection box is used to supply the waste heat from the cement production line, and the air outlet of the drying air collection box is connected to the waste heat inlet through the drying air chamber.

[0010] According to the drying device provided by this utility model, the waste heat inlet is located below the exhaust port.

[0011] According to the drying device provided by this utility model, the outer shell is provided with a feeding port and a discharging port that communicate with the drying chamber; the feeding port and the discharging port are respectively arranged at intervals along the axial direction of the outer shell; The drying device further includes: A feeding mechanism, located in the drying chamber, is used to transport fuel entering the drying chamber from the feed inlet to the discharge outlet.

[0012] The second aspect of this utility model provides a cement kiln waste heat utilization system, comprising: A cement kiln is used to calcine raw cement meal into cement clinker. The air outlet of the cement kiln is connected to the air inlet of the air cooler; the head of the air cooler has a first outlet. A waste heat recovery furnace and a dust collection device are provided, wherein the air inlet of the waste heat recovery furnace is connected to the first outlet, and the air outlet of the waste heat recovery furnace is connected to the dust collection device. In any of the above-mentioned drying devices, the air outlet of the dust collection device is connected to the waste heat inlet of the drying device.

[0013] According to the cement kiln waste heat utilization system provided by this utility model, the tail end of the cooler is provided with a second outlet, and the second outlet is connected to the waste heat inlet of the drying device in sequence through a control valve and a dust collector.

[0014] According to the cement kiln waste heat utilization system provided by this utility model, the exhaust port of the drying device is connected to the cooler in sequence through a gas-solid separator, an induced draft fan, a second air collector, and a cooling fan.

[0015] The drying device provided by this utility model utilizes waste heat from the cement production line by designing the waste heat inlet to supply the waste heat. This significantly reduces energy consumption and operating costs in the drying process, achieving cascaded energy utilization and meeting environmental protection requirements for energy conservation and carbon reduction. The exhaust vent is designed to connect to the cooler in the cement production line, returning the high-temperature, humid air carrying water vapor after drying to the cement production line system, forming a closed-loop cycle. This not only prevents direct emission of heat and dust into the atmosphere, avoiding environmental pollution, but also further recovers and utilizes the waste heat, improving the overall energy efficiency of the system. The axial reciprocating material-turning mechanism effectively turns the lower layer of moist fuel to the upper layer for full contact with hot air, while simultaneously breaking up potentially agglomerated materials. This increases the contact area and time between the fuel and hot air, thereby enhancing heat and mass transfer efficiency and achieving rapid and uniform drying, solving the problems of low efficiency and uneven drying in traditional dryers. Furthermore, this structure is simpler and more reliable than complex material-turning devices, reducing equipment failure rates and facilitating later maintenance and repair. This invention achieves the purpose of drying fuels with high moisture content and utilizing waste heat generated in cement production lines.

[0016] The cement kiln waste heat utilization system provided by this utility model has at least the above-mentioned advantages because it includes the aforementioned drying device, which will not be elaborated further here. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the drying device provided by this utility model.

[0019] Figure 2 This is a schematic diagram of the material turning mechanism of the drying device provided by this utility model.

[0020] Figure 3 This is a schematic diagram of the structure of the cement kiln waste heat utilization system provided by this utility model.

[0021] Figure label: 11. Cement kiln; 12. Cooler; 13. Waste heat recovery furnace; 14. Dust collection device; 15. Control valve; 16. Dust collector; 17. Gas-solid separator; 18. Exhaust fan; 19. Second air collection box; 20. Cooling fan; 21. Kiln head exhaust fan; 110. Outer shell; 101. Drying chamber; 102. Feeding port; 103. Discharge port; 104. Exhaust vent; 120. Tilting mechanism; 121. Rake frame; 122. Tilting drive component; 123. Connecting shaft; 124. Rake blade; 130. Drying air chamber; 140. Drying air collection box. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of this utility model clearer, the technical solutions of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0023] In the description of this specification, it should be noted that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are used only for the convenience of describing this specification. They do not indicate or imply that the device or component referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this specification. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of this specification, it should be noted that, unless otherwise expressly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this utility model based on the specific circumstances.

[0025] In this specification, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0026] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this specification. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0027] In the embodiments of this specification, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent three situations: A exists alone, A and B exist simultaneously, and B exists alone.

[0028] like Figures 1 to 2 As shown, a specific embodiment of the first aspect of this utility model provides a drying device. The drying device provided in this embodiment is not limited to drying alternative fuels, but can also be used to dry other materials. In this specific embodiment, the application scenarios of the drying device are not limited.

[0029] like Figures 1 to 2 As shown, the drying device provided in the specific embodiment of the first aspect of this utility model includes a shell 110, a feeding mechanism, and a turning mechanism 120.

[0030] The outer casing 110 contains a drying chamber 101. The outer casing 110 has a feeding port 102, a discharge port 103, a waste heat inlet, and an exhaust port 104 connected to the drying chamber 101. The feeding port 102 and discharge port 103 are spaced apart along the axial direction of the outer casing 110. The waste heat inlet is used to supply waste heat from the cement production line. This design utilizes waste heat that might otherwise be wasted in the cement production line as a heat source, reducing energy consumption and operating costs in the drying process, achieving cascaded energy utilization, and meeting the environmental protection requirements of energy conservation and carbon reduction. The exhaust port 104 is connected to the cooler 12 in the cement production line to return the high-temperature, humid air carrying water vapor after drying to the cement production line system, forming a closed-loop cycle. This not only avoids direct emission of heat and dust into the atmosphere causing environmental pollution but also further recovers and utilizes the waste heat, improving the overall energy efficiency of the system.

[0031] A feeding mechanism is located in the drying chamber 101 to transport fuel entering the drying chamber 101 from the feed inlet 102 to the discharge outlet 103. Specifically, the feeding mechanism is located at the bottom of the drying chamber 101. Fuel entering the drying chamber 101 from the feed inlet 102 falls onto the feeding mechanism and is then transported to the discharge outlet 103. This ensures a continuous and stable flow of material within the drying chamber 101, providing a foundation for large-scale continuous drying operations.

[0032] The material turning mechanism 120 includes a rake frame 121 and a turning drive component 122. The rake frame 121 is located in the drying chamber 101, and the turning drive component 122 is connected to the rake frame 121 to drive the rake frame 121 to reciprocate along the axial direction of the outer shell 110 for material turning. This reciprocating turning mechanism can turn the lower layer of wet fuel to the upper layer to fully contact the hot air, while simultaneously breaking up potentially agglomerated materials. This increases the contact area and contact time between the fuel and the hot air, thereby enhancing heat and mass transfer efficiency and achieving a rapid and uniform drying effect, solving the problems of low efficiency and uneven drying in traditional dryers. Furthermore, the structure of this turning mechanism 120 is simpler and more reliable than complex turning devices, reducing equipment failure rates and facilitating later maintenance and repair.

[0033] Furthermore, the waste heat inlet is located below the exhaust vent 104. Specifically, a waste heat inlet is provided at the bottom of the outer casing 110, and an exhaust vent 104 is provided at the top of the outer casing 110. In other words, this embodiment uses a bottom-inlet, top-outlet method to introduce waste heat into the drying chamber 101. This structural layout fully utilizes the physical characteristics of hot air, which has a low density and naturally rises, allowing the high-temperature waste heat airflow entering from the bottom to pass through the entire fuel layer from bottom to top. This design forces the hot air to have sufficient contact with the fuel. Compared to the method of letting the hot air sweep over the upper layer of materials, this bottom-inlet, top-outlet waste heat introduction method in this embodiment can ensure that heat is transferred to every corner of the drying chamber 101 as much as possible, improving the thermal energy utilization rate. In addition, in this embodiment, the use of this cross-flow cross-heat exchange method of hot air upward and fuel horizontal delivery can improve the overall drying efficiency and speed while ensuring drying quality.

[0034] Preferably, the bottom of the outer casing 110 may also have a discharge port 103, and the top of the outer casing 110 may have a feeding port 102. This vertical layout with top feeding and bottom discharging utilizes gravity to assist in the transport and discharge of fuel. This not only simplifies the structure of the inlet and outlet and reduces the energy consumption of the related conveying mechanism, but also ensures that the fuel can smoothly enter the drying chamber 101 and be discharged, reducing the risk of material accumulation or blockage at both ends of the equipment.

[0035] In other words, the bottom of the outer casing 110 has a discharge port 103, the bottom of the side wall of the outer casing 110 has a waste heat inlet, and the top of the outer casing 110 has a feeding port 102 and an exhaust port 104. The feeding port 102 and the exhaust port 104 are respectively arranged at intervals along the axial direction of the outer casing 110 at the left and right ends of the outer casing 110, and the discharge port 103 is located below the exhaust port 104. This cross-flow heat exchange method, with hot air flowing upward and fuel transported horizontally, can improve the overall drying efficiency and speed while ensuring drying quality.

[0036] In some embodiments of this utility model, the drying device further includes a drying air chamber 130 and a drying air collection box 140. The air inlet of the drying air collection box 140 is used to supply waste heat from the cement production line, and the air outlet of the drying air collection box 140 is connected to the waste heat inlet through the drying air chamber 130. This effectively adds a buffer and rectification intermediate link between the waste heat source of the cement production line and the main body of the drying chamber 101. By setting up the drying air collection box 140, the potentially unstable or uneven waste heat airflow from the cement production line can be effectively collected and initially stabilized, providing a stable air source for subsequent air supply. Simultaneously, the drying air collection box 140 can also settle large dust particles, pre-purify the waste heat gas, reduce impurities entering the drying chamber 101, protect the equipment, and prevent fuel contamination. The function of the drying air chamber 130 is to perform secondary distribution and rectification of the concentrated airflow from the drying air collection box 140, ensuring that the wind speed and pressure of the hot air are relatively uniformly distributed across the entire inlet cross-section when it enters the waste heat inlet of the drying chamber 101. This uniform air distribution ensures that hot air passes through the entire material layer from bottom to top in a relatively uniform manner, thus effectively avoiding channeling or dead zones caused by excessive or insufficient local airflow. It also ensures that all fuels can receive sufficient and relatively uniform heat exchange, ultimately improving drying efficiency and the uniformity of finished product quality.

[0037] like Figure 2As shown, in some embodiments of this utility model, the material turning drive 122 includes one of a linear motor, a pneumatic cylinder, or a hydraulic cylinder. When a linear motor is used, since it can directly convert electrical energy into linear motion, eliminating the intermediate transmission mechanism, it can achieve precise servo control of the movement speed, acceleration, and displacement of the rake frame 121. This allows for flexible adjustment of the material turning strategy based on the real-time drying status of the material, achieving better process control. It also has the advantages of simple structure, high transmission efficiency, and stable operation. When a pneumatic cylinder is used as the drive component, its fast response speed, simple structure, low cost, and clean and pollution-free operation make it a very economical, efficient, and easy-to-maintain drive system, ideal for applications with strict cost control and demanding working environments. When a hydraulic cylinder is used, it provides a powerful and stable driving force, especially suitable for handling heavy fuels with high density, strong viscosity, or easy caking. It ensures that the rake frame 121 can reliably reciprocate under heavy loads, guaranteeing effective turning and crushing of difficult materials.

[0038] like Figure 2 As shown, in some embodiments of this utility model, the rake frame 121 includes a connecting shaft 123 and multiple rake blades 124. This split-type structural design is clear, and manufacturing and maintenance are relatively simple. The connecting shaft 123 serves as the core load-bearing and transmission component, while the rake blades 124 serve as the working components that directly interact with the material. Their functions are clearly defined, ensuring the stability and reliability of the entire material turning mechanism 120. One end of the connecting shaft 123 is connected to the material turning drive 122, and the other end extends axially along the outer casing 110. This design ensures that the reciprocating motion generated by the material turning drive 122 can be transmitted to the entire rake frame 121, allowing the material turning action to cover the entire axial length of the drying chamber 101, thereby providing continuous and thorough turning of the fuel throughout the conveying process. Multiple rake blades 124 are spaced apart along the axial direction of the outer casing 110 on the connecting shaft 123. This allows for segmented and repeated agitation, crushing, and scattering of the elongated fuel bed during the reciprocating motion of the rake frame 121. This not only reduces the risk of uneven fuel distribution, such as accumulation at the front and sparse distribution at the rear, caused by the overall shifting of fuel during transport, but also increases the dynamic contact area and frequency between fuel particles and hot air, continuously renewing the heat exchange surface of the gas-solid two-phase system. This enables the breaking up of wet fuel clumps, promotes the rapid escape of internal moisture, and achieves deep drying of the material from the inside out, improving drying efficiency and the uniformity of the final product quality.

[0039] Optionally, the side of the rake blade 124 furthest from the bottom of the drying chamber 101 is an inclined surface. In other words, the upper side of the rake blade 124 is an inclined surface. This design allows the fuel that has been turned over to the top of the rake blade 124 to roll to one side of the rake blade 124 as guided by the inclined surface during the reciprocating motion of the rake blade 124. This not only effectively breaks up clumps of fuel formed due to moisture, but also increases the dynamic contact between fuel particles and hot air, continuously renewing the gas-solid heat exchange interface. This ensures that heat can be transferred to the interior of the fuel relatively quickly, accelerates the evaporation of moisture, reduces the risk of local overheating or incomplete drying, and improves the uniformity and efficiency of drying. In addition, the inclined surface design encounters less resistance when moving through the material compared to a vertical surface. This helps to reduce the load and energy consumption of the turning drive component 122, making the entire turning mechanism 120 operate more smoothly and reliably, and reducing the risk of material jamming or equipment wear.

[0040] Optionally, the rake blades 124 are provided with through holes along the axial direction of the housing 110. The through holes are used to allow fuel to pass through, preventing fuel from accumulating between adjacent rake blades 124.

[0041] Preferably, there are multiple through holes, which are evenly distributed on the rake blades 124. This can reduce the risk of fuel accumulation between adjacent rake blades 124 while ensuring the material turning effect.

[0042] In some embodiments of this utility model, the feeding mechanism is a belt conveyor mechanism. Using a belt conveyor mechanism as the feeding mechanism results in a relatively simple structure and stable, reliable operation. It enables continuous and uniform conveying of fuel from the feed port 102 to the discharge port 103, providing a stable material foundation for the uniform stirring of the subsequent turning mechanism 120 and the uniform drying with hot air. By adjusting the operating speed of the belt conveyor mechanism, the residence time of fuel in the drying chamber 101 can be easily controlled, allowing for flexible adjustments based on the initial and target moisture content of the fuel. This ensures that different batches of fuel achieve the desired drying effect, improving the process adaptability and flexibility of the entire drying system. Furthermore, the belt conveyor mechanism has low maintenance costs, is easy to repair and replace, and helps reduce the long-term operating costs of the equipment.

[0043] Specifically, the conveyor mechanism includes a conveyor belt, a main pulley, a driven pulley, and a motor; the main pulley and the driven pulley are arranged axially at intervals along the housing 110. The conveyor belt is fitted onto the main pulley and the driven pulley, and the electrode is connected to the main pulley to drive the main pulley to rotate, thereby transporting the fuel to the discharge port 103.

[0044] like Figure 3As shown, the second aspect of this utility model provides a cement kiln waste heat utilization system. This system includes a cement kiln 11, a cooler 12, a waste heat recovery furnace 13, a dust collection device 14, and a drying device as described in any of the above embodiments. By organically connecting the core equipment of cement production (i.e., the cement kiln 11 and the cooler 12, etc.) with the drying device, an energy cascade utilization and material circulation system is constructed, which can recover the waste heat generated during production, improving the energy efficiency and economic benefits of the entire production line.

[0045] The cement kiln 11 is preferably a rotary kiln, used to calcine cement raw materials into cement clinker.

[0046] Cooler 12 is preferably a grate cooler. The outlet of cement kiln 11 is connected to the inlet of cooler 12; a first outlet is opened at the head of cooler 12. The inlet of waste heat recovery furnace 13 is connected to the first outlet. In this way, a portion of the high-grade waste heat gas (usually above 500°C) in cooler 12 can be preferentially sent to waste heat recovery furnace 13 for power generation or high-pressure steam generation, realizing the efficient recovery and utilization of high-grade waste heat, which is the first stage of energy recovery.

[0047] The exhaust port of the waste heat recovery furnace 13 is connected to the dust collection device 14. The dust collection device 14 can purify the waste heat gas before it enters the next stage of utilization (i.e., drying), effectively removing a large amount of dust entrained in the gas. This avoids dust clogging and wear on subsequent drying devices and pipelines, ensuring the long-term stable operation of the entire system; on the other hand, the recovered dust can be returned to the production system, reducing raw material waste.

[0048] The outlet of the dust collection device 14 is connected to the waste heat inlet of the drying device. This connection realizes the second-level cascade utilization of energy, using the medium-low temperature waste gas (usually around 100°C), which has been cooled after power generation but still has considerable heat, as a heat source for drying low-moisture fuel. This design can convert low-grade waste heat that might otherwise be directly discharged into the atmosphere into effective productivity, reducing fuel processing costs and the overall energy consumption of cement production. It also creates conditions for utilizing low-cost, high-moisture alternative fuels, and has the dual advantages of energy saving, emission reduction, cost reduction, and efficiency improvement.

[0049] Optionally, a kiln head exhaust fan 21 is also provided at the air outlet of the dust collection device 14 to discharge the hot air discharged from the waste heat recovery furnace 13 to the waste heat inlet of the outer shell 110, providing power for the hot air.

[0050] In some embodiments of this invention, a second outlet is provided at the tail end of the cooler 12. This second outlet is connected to the waste heat inlet of the drying device via a control valve 15 and a dust collector 16. This design provides an alternative or supplementary heat source in addition to the exhaust gas from the waste heat recovery furnace 13. Although the gas temperature at the tail end of the cooler 12 is lower than at the head, it still retains considerable heat. Directly utilizing this low-temperature waste heat can further improve the overall energy recovery rate of the system. By setting the control valve 15, flexible control of the heat source supply to the drying device is achieved. Operators can precisely open, close, or adjust the flow rate of the supplementary hot air from this path according to the actual moisture content of the fuel, the processing volume, and the operating conditions of the cooler 12 and the waste heat furnace, thereby enabling on-demand heating based on the actual moisture content and processing volume of the fuel. When the heat from the waste heat recovery furnace 13 is insufficient or fluctuates, this path can be opened for supplementation, ensuring the stability and efficiency of the drying process; when the heat is sufficient, it can be closed to avoid unnecessary heat waste.

[0051] A dust collector 16 is installed before the gas enters the drying device to ensure the cleanliness of the gas entering the drying device. This can effectively prevent dust from the cooler 12 from causing wear and blockage to the feeding mechanism and turning mechanism 120 inside the drying device, or from contaminating the dried fuel. This effectively ensures the safe and long-term operation of the drying equipment and the quality of the final product.

[0052] In some embodiments of this invention, the exhaust port 104 of the drying device is connected to the cooler 12 in sequence via a gas-solid separator 17, an induced draft fan 18, a second air collection box 19, and a cooling fan 20. This design constructs a closed-loop waste gas circulation system.

[0053] Firstly, the gas-solid separator 17 effectively recovers fine fuel powder entrained in the waste gas due to material turnover. This avoids the loss of valuable fuel and improves raw material utilization. Secondly, it protects subsequent critical equipment such as fan impellers, preventing equipment damage caused by particle abrasion and reducing maintenance costs.

[0054] Next, an induced draft fan 18 is installed to provide suction for the entire drying and exhaust system, ensuring a stable negative pressure environment inside the drying unit. This not only effectively prevents dust and water vapor generated during the drying process from leaking into the workshop and improving the working environment on the production site, but also ensures that the hot air required for drying can pass through the material layer stably and evenly, which is a key guarantee for achieving efficient and controllable drying.

[0055] Finally, the treated exhaust gas is connected to the cooler 12 via the second air collector 19 and the cooling fan 20, realizing the reuse of the drying exhaust gas and completing a closed-loop energy cycle. Some of the residual heat in the drying exhaust gas is returned to the cooler 12 as a supplementary air source for cooling the clinker. This preheated gas replaces some of the ambient temperature air, increasing the temperature of the secondary and tertiary air discharged from the cooler 12 and the cement kiln 11. This indirectly reduces fuel consumption in the main combustion system, further improving the overall thermal efficiency of the entire cement production line. Simultaneously, this closed-loop design incorporates all the exhaust gas generated during drying into the system for digestion, avoiding the direct emission of high-temperature, high-humidity exhaust gas and dust into the atmosphere, thus providing both energy-saving and environmental benefits.

[0056] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.

Claims

1. A drying apparatus, characterized in that, include: The outer shell (110) has a drying chamber (101) inside; the outer shell (110) has a waste heat inlet and an exhaust vent (104) communicating with the drying chamber (101); the waste heat inlet is used to supply waste heat from the cement production line; the exhaust vent (104) is used to connect to the cooler (12) in the cement production line. The material turning mechanism (120) includes a rake frame (121) and a material turning drive (122); the rake frame (121) is located in the drying chamber (101), and the material turning drive (122) is connected to the rake frame (121) to drive the rake frame (121) to reciprocate along the axial direction of the outer shell (110) for material turning.

2. The drying apparatus according to claim 1, characterized in that, The rake frame (121) includes: The connecting shaft (123) is connected at one end to the material turning drive (122) and at the other end extends along the axial direction of the outer shell (110); Multiple rake blades (124) are mounted on the connecting shaft (123) at axial intervals along the housing (110).

3. The drying apparatus according to claim 2, characterized in that, The rake blade (124) has a through hole along the axial direction of the outer shell (110).

4. The drying apparatus according to claim 2, characterized in that, The material turning drive (122) includes one of a linear motor, a cylinder or a hydraulic cylinder.

5. The drying apparatus according to claim 1, characterized in that, Also includes: The drying air chamber (130) and the drying air collection box (140) are provided. The air inlet of the drying air collection box (140) is used to supply the waste heat of the cement production line. The air outlet of the drying air collection box (140) is connected to the waste heat inlet through the drying air chamber (130).

6. The drying apparatus according to claim 1, characterized in that, The waste heat inlet is located below the exhaust vent (104).

7. The drying apparatus according to any one of claims 1 to 6, characterized in that, The outer shell (110) is provided with a feeding port (102) and a discharging port (103) communicating with the drying chamber (101); the feeding port (102) and the discharging port (103) are respectively arranged at intervals along the axial direction of the outer shell (110); The drying device further includes: A feeding mechanism, located in the drying chamber (101), is used to transport fuel entering the drying chamber (101) from the feed port (102) to the discharge port (103).

8. A waste heat utilization system for cement kilns, characterized in that, include: Cement kiln (11) is used to calcine raw cement meal into cement clinker; The air outlet of the cement kiln (11) is connected to the air inlet of the air cooler (12); the head of the air cooler (12) is provided with a first outlet; Waste heat recovery furnace (13) and dust collection device (14), wherein the air inlet of the waste heat recovery furnace (13) is connected to the first outlet, and the air outlet of the waste heat recovery furnace (13) is connected to the dust collection device (14). The drying apparatus according to any one of claims 1 to 7, wherein the air outlet of the dust collection device (14) is connected to the waste heat inlet of the drying apparatus.

9. The cement kiln waste heat utilization system according to claim 8, characterized in that, The cooler (12) has a second outlet at its tail end, and the second outlet is connected to the waste heat inlet of the drying device in sequence through a control valve (15) and a dust collector (16).

10. The cement kiln waste heat utilization system according to claim 8, characterized in that, The exhaust port (104) of the drying device is connected to the cooler (12) in sequence through the gas-solid separator (17), the induced draft fan (18), the second air collector (19) and the cooling fan (20).

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