Preheater device

Abstract

The utility model discloses a preheater device which comprises N heat exchangers which are sequentially connected from bottom to top, high-temperature flue gas in a decomposing furnace enters from the lowest first heat exchanger and is discharged from the uppermost Nth heat exchanger, and N is larger than 5; every two adjacent heat exchangers are connected through a connecting pipeline, the inlet end of each connecting pipeline is connected with an air outlet of the corresponding heat exchanger located on the lower portion, and the outlet end of each connecting pipeline is connected with an air inlet of the corresponding heat exchanger located on the upper portion. The number of the heat exchangers located at the uppermost portion is at least two, and the multiple heat exchangers are arranged in parallel. The preheater device further comprises a feeding pipeline and a material scattering box used for evenly scattering materials. The feeding pipeline is connected to the connecting pipeline of the Nth heat exchanger through the material scattering box. And the discharge port of the upper heat exchanger in two adjacent heat exchangers is connected to the connecting pipeline at the air inlet of the lower heat exchanger through the scattering box. The preheater device can reduce the temperature of an outlet of waste gas exhausted by a preheating system, and efficient heat exchange is achieved.

Description

Technical Field

[0001] The utility model relates to the field of cement production, in particular to a preheater device. Background Art

[0002] As a major CO2 emitter, the national carbon peak and carbon neutrality goals have a profound impact on my country's cement industry. Controlling the scale of cement production and achieving a green and low-carbon transformation in the cement production and application process are one of the key tasks for my country to practice the concept of ecological civilization and achieve the "dual carbon" goals as scheduled.

[0003] According to the "Energy Efficiency Benchmarking and Baseline Levels for Key Areas of High-Energy-Consuming Industries (2022 Edition)," the benchmark energy efficiency level for cement clinker is 100 kg of standard coal per ton, and the base level is 117 kg of standard coal per ton. However, as of the end of 2020, based on the electric thermal equivalent method, approximately 5% of the cement industry's production capacity had energy efficiency exceeding the benchmark level, while approximately 24% had energy efficiency below the benchmark level. Therefore, there is an urgent need to improve the energy efficiency of cement clinker production lines.

[0004] Due to the inability to evenly mix the material and the high-temperature gas and the insufficient number of stages of the heat exchanger, the heat exchange efficiency of the preheating system of the cement clinker production line is low. The outlet temperature of the exhaust gas after heat exchange is about 330°C, and the temperature of the discharged exhaust gas is still relatively high, thus causing energy waste in the cement clinker production line. Utility Model Content

[0005] The purpose of the utility model is to provide a preheater device, which can effectively improve the heat exchange efficiency of the preheater and reduce the outlet temperature of the exhaust gas discharged from the preheating system by setting more heat exchange stages and improving the mixing degree of the material and the high-temperature gas.

[0006] In order to achieve the above-mentioned object, the utility model provides a preheater device, which comprises N heat exchangers (11) connected sequentially from bottom to top, wherein the high-temperature flue gas in the decomposition furnace (6) enters from the first heat exchanger (1) at the bottom and is discharged from the Nth heat exchanger (10) at the top, where N is greater than 5;

[0007] Two adjacent heat exchangers (11) are connected via a connecting pipe (2), the inlet end of the connecting pipe (2) is connected to the air outlet (44) of the heat exchanger (11) located below, and the outlet end of the connecting pipe (2) is connected to the air inlet (43) of the heat exchanger (11) located above;

[0008] At least two of the heat exchangers (11) located at the top are provided, and a plurality of the heat exchangers (11) are provided in parallel;

[0009] The preheater device further comprises a feed pipeline (3) and a spreading box (5) for evenly spreading material, wherein the feed pipeline (3) is connected to the connecting pipeline (2) of the Nth heat exchanger (10) through the spreading box (5); the discharge port (45) of the upper heat exchanger (11) of the two adjacent heat exchangers (11) is connected to the connecting pipeline (2) at the air inlet (43) of the lower heat exchanger (11) through the spreading box (5).

[0010] Preferably, the material spreading box (5) comprises a body, a material spreading inlet (81), a material spreading outlet and a material spreading plate (82), wherein the material spreading inlet (81) is located at the upper part of the body, the material spreading outlet is located at the lower part of the body, and the material spreading outlet is sealedly connected to the connecting pipe (2);

[0011] The spreading plate (82) is arranged inside the main body, and the spreading plate (82) extends obliquely downward to the spreading outlet, and the cross-sectional width of the spreading plate (82) gradually increases from top to bottom.

[0012] Preferably, a plurality of dispersion guide rails (83) are provided on the spreading plate (82), and the plurality of dispersion guide rails (83) are located on both sides of the spreading plate (82). The dispersion guide rails (83) on both sides are inclined toward the two side edges of the spreading plate (82), and the dispersion guide rails (83) protrude from the upper surface of the spreading plate (82).

[0013] Preferably, an auxiliary dispersion guide rail (85) is provided at the lower portion of the spreading plate (82), and the auxiliary dispersion guide rail (85) is located between the dispersion guide rails (83) on both sides, and the auxiliary dispersion guide rail (85) is arranged in a herringbone shape.

[0014] Preferably, a distance is provided between the upper end of the dispersion guide rail (83) and the upper end of the spreading plate (82).

[0015] Preferably, a distance is provided between the material spreading box (5) and the outlet of the connecting pipeline (2), and the time for the raw material powder to pass through the distance is 4-5 seconds.

[0016] Preferably, a constriction is provided below the connection between the material spreading box (5) of the connecting pipeline (2) and the connecting pipeline (2).

[0017] Preferably, the material spreading box (5) is further provided with a blowing pipe (84) capable of spraying gas toward the material spreading box (5), the blowing pipe (84) is arranged to be inclined downward, and the outlet of the blowing pipe (84) is directed toward the material spreading plate (82).

[0018] According to the above technical solution, the preheater device of the present invention includes at least 6 stages of heat exchangers. The high-temperature flue gas in the decomposition furnace enters from the first heat exchanger at the bottom and enters the upper heat exchanger step by step. The raw meal enters from the feed pipeline and enters the lower heat exchanger step by step. In the process of the high-temperature gas moving upward and the low-temperature raw meal moving downward, heat exchange is realized between the high-temperature gas and the low-temperature raw meal.

[0019] Conventional preheater systems only include five stages of heat exchangers. After completing all heat exchange operations, the exhaust gas from the Nth heat exchanger has an outlet temperature of approximately 330°C. This high exhaust temperature results in a certain amount of energy waste. This preheater system includes at least six stages of heat exchangers, which prevents these high-temperature exhaust gases exceeding 300°C from being directly discharged. Instead, they have the opportunity to enter the heat exchanger and exchange heat with the room-temperature raw meal, effectively reducing the exhaust gas outlet temperature and improving the heat exchange efficiency of the preheater system.

[0020] As the value of N increases, the number of heat exchanges required in the preheater device also increases, and the outlet temperature of the exhaust gas discharged by the Nth heat exchanger 10 gradually decreases. When N exceeds 6, the heat exchange efficiency of the Nth heat exchanger 10 also decreases significantly. Therefore, considering the investment cost of the equipment and the efficiency improvement effect, it is preferred to set N=6 and not install the seventh heat exchanger.

[0021] The heat exchanger is configured as a cyclone. Since the high-temperature gas contains clinker from the calciner, clinker is the product of the calciner. Therefore, improving the efficiency of the heat exchanger involves two approaches: first, improving the heat exchange efficiency of the heat exchanger; second, improving the efficiency of the heat exchanger in filtering the clinker, reducing the amount of clinker that is discarded, and thus producing more product while consuming the same amount of energy.

[0022] Preferably, the heat exchanger is configured as a cyclone, which can effectively filter the clinker in the high-temperature gas, and the cyclone also has the advantages of high temperature resistance and high filtering efficiency.

[0023] The cyclone consists of an air inlet, an air outlet and a discharge port. The high-temperature gas enters the cyclone along the tangential direction from the air inlet and makes a spiral motion inside the cyclone. The high-speed rotation of the gas generates centrifugal force. The rotating solid dust will be separated from the gas and slide down along the side wall of the cyclone, and finally flow out from the discharge port.

[0024] After the high-temperature flue gas from the decomposition furnace enters the first heat exchanger, it flows out of the outlet and enters the heat exchanger on the previous level. The solid dust filtered by the first heat exchanger flows out of the discharge port and enters the decomposition furnace. After entering the heat exchanger on the previous level, the high-temperature gas first moves in a counterclockwise spiral within the heat exchanger, and finally flows out of the inner cylinder to the outlet and enters the heat exchanger on the previous level. Similarly, the high-temperature gas will enter the heat exchanger on the previous level step by step from bottom to top.

[0025] The solid dust filtered during the operation of the upper-level heat exchanger flows out from the discharge port and enters the connecting pipe connected to the air inlet of the next-level heat exchanger. The solid dust is sprayed into the connecting pipe, and high-temperature gas flows in the connecting pipe. Under the action of the flowing high-temperature gas, the solid dust is mixed with the high-temperature gas in the connecting pipe. While heat exchange occurs, the raw material powder will move with the high-temperature gas to the air inlet of the next-level heat exchanger. Similarly, the raw material powder realizes step-by-step movement from top to bottom.

[0026] After the raw meal enters the preheater, heat exchange occurs when it comes into contact with the hot gas. During this heat exchange, the raw meal moves downward step by step, gradually increasing in temperature, while the hot gas moves upward step by step, gradually decreasing in temperature. Therefore, as the raw meal's temperature rises, the hot gas it encounters also becomes increasingly hotter, ensuring that the raw meal's temperature is reliably elevated during its downward movement.

[0027] Before entering the heat exchanger, the raw meal first enters the connecting pipe and exchanges heat with the high-temperature gas within it. Therefore, by providing a spreading box to evenly distribute the raw meal into the connecting pipe, the uniformity of the mixing of the raw meal and the high-temperature gas can be effectively improved, resulting in a more uniform mixing of the raw meal and the high-temperature gas within the connecting pipe, thus achieving a better heat exchange effect within the connecting pipe.

[0028] The raw meal can enter the connecting pipeline in a more dispersed manner through the spreading box. In one embodiment, the spreading box is configured in a bell-mouth shape, with the larger opening end connected to the connecting pipeline. This allows the raw meal powder to have a dispersed movement tendency when entering the connecting pipeline. Under the action of this dispersed movement tendency, the raw meal powder can be more effectively dispersed within the connecting pipeline, thereby improving the uniformity of the mixing of the raw meal powder and the high-temperature gas and enhancing the heat exchange efficiency.

[0029] After the raw meal powder and high-temperature gas that are evenly mixed in the connecting pipeline enter the heat exchanger, a better heat exchange effect can be obtained, thereby more reliably improving the heat exchange efficiency of the preheater device.

[0030] Other features and advantages of the present invention will be described in detail in the subsequent detailed description of the embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0032] Figure 1 It is a structural schematic diagram of a preheater device;

[0033] Figure 2 It is a schematic diagram of the last stage of cyclones connected in parallel;

[0034] Figure 3 yes Figure 2 AA cross-section of

[0035] Figure 4 It is a structural diagram of a cyclone;

[0036] Figure 5 yes Figure 4 A top view of

[0037] Figure 6 It is a three-dimensional picture of a spreading box;

[0038] Figure 7 yes Figure 6 The main view;

[0039] Figure 8 It is a schematic diagram of a material spreading box connected to a connecting pipe.

[0040] Description of Reference Numerals

[0041] 1 first heat exchanger 10 Nth heat exchanger

[0042] 11 Heat exchanger 2 connecting pipe

[0043] 3 Feeding pipeline 41 inner cylinder

[0044] 42 volute 5 spreading box

[0045] 43 air inlet 44 air outlet

[0046] 45 discharge port 6 decomposition furnace

[0047] 71 tertiary air inlet 81 material spreading inlet

[0048] 82 spreading plate 83 dispersion guide rail

[0049] 84 injection pipe 85 auxiliary dispersion guide rail DETAILED DESCRIPTION

[0050] The following is a detailed description of the specific embodiments of the present invention in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention and are not intended to limit the present invention.

[0051] In the present utility model, unless otherwise stated, directional words contained in the terms such as "lower, upper, below, adjacent, above, inclined downward" merely represent the orientation of the term in normal use, or are common names understood by those skilled in the art, and should not be regarded as limitations on the term.

[0052] See also Figure 1 A preheater device includes N heat exchangers 11 connected sequentially from bottom to top, and the high-temperature flue gas in the decomposition furnace 6 enters from the first heat exchanger 1 at the bottom and is discharged from the Nth heat exchanger 10 at the top, where N is greater than 5;

[0053] Two adjacent heat exchangers 11 are connected via a connecting pipe 2, the inlet end of the connecting pipe 2 is connected to the air outlet 44 of the lower heat exchanger 11, and the outlet end of the connecting pipe 2 is connected to the air inlet 43 of the upper heat exchanger 11;

[0054] At least two heat exchangers 11 are provided at the top, and multiple heat exchangers 11 are provided in parallel;

[0055] The preheater device also includes a feed pipeline 3 and a spreading box 5 for evenly spreading materials. The feed pipeline 3 is connected to the connecting pipeline 2 of the Nth heat exchanger 10 through the spreading box 5; the discharge port 45 of the upper heat exchanger 11 among the two adjacent heat exchangers 11 is connected to the connecting pipeline 2 at the air inlet 43 of the lower heat exchanger 11 through the spreading box 5.

[0056] Through the implementation of the above technical solution, the preheater device includes at least 6 stages of heat exchangers 11. The high-temperature flue gas in the decomposition furnace 6 enters from the first heat exchanger 1 at the bottom and enters the upper heat exchanger 11 step by step. The raw meal enters from the feed pipeline 3 and enters the lower heat exchanger 11 step by step. In the process of the high-temperature gas moving upward and the low-temperature raw meal moving downward, heat exchange is realized between the high-temperature gas and the low-temperature raw meal.

[0057] A typical preheater device only includes five stages of heat exchangers 11. After completing all heat exchange operations, the exhaust gas discharged from the Nth heat exchanger 10 has an outlet temperature of approximately 330°C. Due to the high exhaust gas temperature, this results in a certain amount of energy waste. This preheater device includes at least six stages of heat exchangers 11, so that these high-temperature exhaust gases exceeding 300°C are not directly discharged, but still have the opportunity to enter the heat exchanger 11 for heat exchange with the room-temperature raw meal, thereby effectively reducing the exhaust gas outlet temperature and improving the heat exchange efficiency of the preheater device.

[0058] As the value of N increases, the number of heat exchanges required in the preheater device also increases, and the outlet temperature of the exhaust gas discharged by the Nth heat exchanger 10 gradually decreases. When N exceeds 6, the heat exchange efficiency of the Nth heat exchanger 10 also decreases significantly. Therefore, considering the investment cost of the equipment and the efficiency improvement effect, it is preferred to set N=6 and not install the seventh heat exchanger.

[0059] Heat exchanger 11 is configured as a cyclone. Since the high-temperature gas contains clinker from the calciner, which is the product of the calciner, the efficiency of heat exchanger 11 can be improved in two ways: first, by increasing the heat exchange efficiency of heat exchanger 11; second, by improving the efficiency of clinker filtration in heat exchanger 11, thereby reducing the amount of clinker that is discarded and producing more product while consuming the same amount of energy.

[0060] Preferably, the heat exchanger 11 is configured as a cyclone, which can effectively filter the clinker in the high-temperature gas. The cyclone also has the advantages of high temperature resistance and high filtering efficiency.

[0061] The cyclone includes an air inlet 43, an air outlet 44 and a discharge port 45. The high-temperature gas enters the cyclone along the tangential direction from the air inlet 43 and performs a spiral motion inside the cyclone. The high-speed rotation of the gas generates centrifugal force. The rotating solid dust will be separated from the gas and slide downward along the side wall of the cyclone, and finally flow out from the discharge port 45.

[0062] After the high-temperature flue gas from the decomposition furnace enters the first heat exchanger 1, it flows out of the outlet 43 and enters the heat exchanger 11 of the previous stage. The solid dust filtered by the first heat exchanger 1 flows out of the discharge port 45 and enters the decomposition furnace. After entering the previous heat exchanger 11, the high-temperature gas first moves in a counterclockwise spiral within the heat exchanger 1, and finally flows out of the inner cylinder 41 to the outlet 43 and enters the previous heat exchanger 11. Similarly, the high-temperature gas enters the previous heat exchanger 11 step by step from bottom to top.

[0063] The solid dust filtered out during the operation of the upper-level heat exchanger 1 flows out from the discharge port 45 and enters the connecting pipe 2 connected to the air inlet 43 of the next-level heat exchanger 11. The solid dust is sprayed into the connecting pipe 2. High-temperature gas flows in the connecting pipe 2. Under the action of the flowing high-temperature gas, the solid dust is mixed with the high-temperature gas in the connecting pipe 2. While heat exchange occurs, the raw material powder will move with the high-temperature gas to the air inlet 43 of the next-level heat exchanger 1. Similarly, the raw material powder realizes step-by-step movement from top to bottom.

[0064] After the raw meal enters the preheater, heat exchange occurs when it comes into contact with the hot gas. During this heat exchange, the raw meal moves downward step by step, gradually increasing in temperature, while the hot gas moves upward step by step, gradually decreasing in temperature. Therefore, as the raw meal's temperature rises, the hot gas it encounters also becomes increasingly hotter, ensuring that the raw meal's temperature is reliably elevated during its downward movement.

[0065] Before entering the heat exchanger 11, the raw material powder first enters the connecting pipe 2 and exchanges heat with the high-temperature gas in the connecting pipe 2. Therefore, by providing the spreading box 5 to evenly distribute the raw material powder into the connecting pipe 2, the uniformity of the mixing of the raw material powder and the high-temperature gas can be effectively improved, so that the raw material powder and the high-temperature gas in the connecting pipe 2 are more evenly mixed, and a better heat exchange effect is obtained in the connecting pipe 2.

[0066] The raw meal can enter the connecting pipe 2 in a more dispersed manner through the spreading box 5. In one embodiment, the spreading box 5 is configured in a bell-mouth shape, with the larger opening end connected to the connecting pipe 2, so that the raw meal powder has a dispersed movement tendency when entering the connecting pipe 2. Under the action of this dispersed movement tendency, the raw meal powder can be more effectively dispersed in the connecting pipe 2, thereby improving the uniformity of the mixing of the raw meal powder and the high-temperature gas and improving the heat exchange efficiency.

[0067] After the raw meal powder and the high-temperature gas that are evenly mixed in the connecting pipeline 2 enter the heat exchanger 11, a better heat exchange effect can be obtained, thereby more reliably improving the heat exchange efficiency of the preheater device.

[0068] In this embodiment, preferably, at least two cyclone tubes are provided at the top, and the multiple cyclone tubes are provided in parallel.

[0069] To improve the filtration efficiency of the final cyclone, the last stage is configured with multiple cyclones connected in parallel. By configuring multiple cyclones, the inner diameter of each cyclone is reduced, which helps dust particles settle after entering the cyclone, thereby effectively improving the gas-solid separation efficiency of the cyclone.

[0070] Preferably, in order to obtain a better gas-solid separation effect, the top cyclone is provided with a longer straight section, which can help dust particles settle after entering the cylinder, thereby reducing the possibility of clinker being carried away by the airflow, and ultimately reducing the probability of hot raw materials being discharged with the exhaust gas, increasing the probability of dust capture and separation, improving the collection efficiency, and thus increasing the output of clinker products.

[0071] Preferably, the cone of the cyclone can be designed as an expansion chamber structure. This structure effectively changes the speed and direction of the airflow, thereby reducing turbulence and eddies, facilitating dust deposition and separation, and further improving the cyclone's clinker collection efficiency. Furthermore, the cone's expansion chamber structure reduces system resistance and energy consumption, while also lowering maintenance frequency and costs.

[0072] In summary, configuring the final heat exchanger 11 with multiple cyclones in parallel effectively improves the clinker collection efficiency of the preheater. This parallel configuration, combined with structural improvements to the cyclones, such as lengthening the straight sections and configuring the tapered sections with expansion chambers, can achieve better gas-solid separation, increase clinker production, and achieve energy savings.

[0073] In this embodiment, preferably, the effective insertion depth of the inner cylinder 41 of the cyclone is L, the effective height of the volute 42 of the cyclone is H, and 0.79H≤L≤0.80H.

[0074] According to the actual production situation, the L / H value is controlled between 0.79-0.80, and the cyclone can obtain better clinker collection efficiency and reduce the outlet temperature of the exhaust gas.

[0075] When the L / H value is controlled between 0.79-0.80, better clinker collection efficiency can be obtained, but at the same time the resistance of the airflow in the cyclone will also increase. The increase in airflow resistance requires an increase in the power of the exhaust fan. Therefore, the energy loss caused by the increase in resistance can be reduced by reducing the airflow speed.

[0076] Increasing the height of the volute 42 of the cyclone increases the cross-sectional area of gas entering the cyclone, effectively reducing the airflow velocity at the cyclone inlet. Therefore, to offset the resistance of the airflow within the cyclone, the height of the cyclone's volute can be appropriately increased to reduce the airflow velocity. When the airflow velocity is reduced, the resistance of the airflow within the cyclone is also reduced accordingly. Preferably, the height of the cyclone's volute is appropriately selected based on actual conditions to ensure an airflow velocity of 16 m / s at the cyclone inlet.

[0077] Preferably, H is set to 5500-6000mm. The height of the conventional cyclone is set to 4000-5000mm. Increasing the effective height H of the volute 42 by 500-1000mm can increase the cross-sectional area of the high-temperature gas when entering the volute 42, thereby achieving control of the airflow velocity at the inlet of the cyclone.

[0078] In this embodiment, preferably, the material spreading box 5 includes a body, a material spreading inlet 81, a material spreading outlet and a material spreading plate 82, the material spreading inlet 81 is located at the upper part of the body, the material spreading outlet is located at the lower part of the body, and the material spreading outlet is sealed with the connecting pipe 2;

[0079] The spreading plate 82 is arranged inside the main body, and the spreading plate 82 extends obliquely downward to the spreading outlet. The cross-sectional width of the spreading plate 82 gradually increases from top to bottom.

[0080] like Figure 7 As shown, the scattering box 5 includes a scattering plate 82 arranged obliquely downward, and the scattering plate 82 extends along the movement direction of the material until it is connected to the connecting pipe 2. The cross-sectional width of the scattering plate 82 gradually increases along the movement direction of the material, so that when the material flows out through the scattering plate 82, the accumulated material can be distributed on the scattering plate 82 under the action of its gravity, thereby achieving the purpose of dispersing the raw material powder and avoiding accumulation of the raw material powder after entering the connecting pipe 2.

[0081] In this embodiment, preferably, a plurality of dispersion guide rails 83 are provided on the spreading plate 82, and the plurality of dispersion guide rails 83 are located on both sides of the spreading plate 82. The dispersion guide rails 83 on both sides are respectively inclined toward the two side edges of the spreading plate 82, and the dispersion guide rails 83 protrude from the upper surface of the spreading plate 82.

[0082] The spreading plate 82 is also provided with a plurality of dispersing guides 83 protruding from the upper surface of the spreading plate 82. After the material falls onto the spreading plate 82, the dispersing guides 83 protrude from the upper surface of the spreading plate 82. Therefore, the dispersing guides 83 can disperse the material. Moreover, the dispersing guides 83 on both sides are inclined toward the sides of the spreading plate 82 along the direction of material movement. That is, the dispersing guides 83 gradually approach the side edges of the spreading plate 82 as they extend.

[0083] After the material enters from the upper spreading inlet 81 and falls into the spreading plate 82, it moves downward along the spreading plate 82 and is dispersed to both sides of the spreading plate 82 under the action of the dispersion guide rail 83. Therefore, under the action of the spreading plate 82, the material can be dispersed, thereby avoiding the accumulation of material in the middle position to a certain extent.

[0084] In this embodiment, preferably, an auxiliary dispersing guide rail 85 is provided at the lower portion of the spreading plate 82 , and the auxiliary dispersing guide rail 85 is located between the dispersing guide rails 83 on both sides, and the auxiliary dispersing guide rail 85 is arranged in a herringbone shape.

[0085] When the material falls from the spreading inlet 81, it usually accumulates more in the middle. Although the dispersion guide 83 can achieve the effect of diverting part of the material to both sides, the material may still accumulate in the middle, which is not conducive to the uniform dispersion of the material after entering the decomposition furnace. Preferably, an auxiliary dispersion guide 85 is also provided at the lower part of the spreading plate 82, such as Figure 8 As shown, the auxiliary dispersion guide 85 is in the shape of a "human." When the accumulated material flows to the upper portion of the "human" shape, the material located below, near the spreading plate 82, is split into two parts by the auxiliary dispersion guide 85 and moves to the sides along the "human" shape, thereby further dispersing the accumulated material in the middle. After the material at the bottom is diverted, the material located above, away from the spreading plate 82, will fall into the middle position of the "human" shaped auxiliary dispersion guide 85 under the action of gravity. As these materials fall, they will impact the spreading plate 82. The impact force can disperse the materials. The middle position of the auxiliary dispersion guide 85 is shaped like a trumpet, which allows the materials to be effectively dispersed. Therefore, the auxiliary dispersion guide 85 can reliably disperse the accumulated materials, dividing the originally accumulated materials into three parts: left, middle, and right.

[0086] Depending on the actual length and width of the spreading plate 82, multiple auxiliary dispersing guides 85 can be provided, nested in descending order. Assuming N auxiliary dispersing guides 85 are arranged from the inside out, the (N-1)th auxiliary dispersing guide 85 is positioned between the two lower legs of the (N)th auxiliary dispersing guide 85, thus achieving a nested arrangement of multiple auxiliary dispersing guides 85 of varying sizes. When the material accumulation is very thick and a single auxiliary dispersing guide 85 is insufficient for effective dispersion, while there is ample space on the spreading plate 82, multiple nested auxiliary dispersing guides 85 can be used to continuously disperse the accumulated material, resulting in a more effective dispersion effect.

[0087] In this embodiment, preferably, a distance is provided between the upper end of the dispersion guide rail 83 and the upper end of the spreading plate 82 .

[0088] There is a distance between the upper end of the dispersion guide rail 83 and the upper end of the spreading plate 82. When the material falls into the spreading plate 82, a part of the material will directly hit the upper surface of the dispersion guide rail 83, thereby causing the material to have an upward impact force. Under the action of this upward impact force, the flat-shaped agglomerated material will be easily broken up, thereby achieving the effect of breaking up this part of the material.

[0089] The material that falls closer to the upper end of the spreading plate 82 will hit the end face of the dispersion guide 83 during its downward movement, thereby obtaining an impact force in an approximately horizontal direction. Since the dispersion guide 83 does not protrude much from the surface of the spreading plate 82, the impact force acts at a lower position. Under the action of this impact force, the thicker, smaller, and elongated agglomerated materials will begin to break from the bottom. Therefore, the collision between the material and the end of the dispersion guide 83 can also achieve the effect of breaking up the material.

[0090] The connection point between the spreading box 5 and the connecting pipeline 2 is set as a distribution point. Preferably, multiple distribution points are set on the connecting pipeline 2, and the multiple distribution points are evenly arranged along the circumference of the connecting pipeline 2, so that the raw material powder entering the connecting pipeline 2 is more evenly distributed.

[0091] In this embodiment, preferably, a gap is provided between the material spreading box 5 and the outlet of the connecting pipeline 2, and the time for the raw material powder to pass through the gap is 4-5 seconds.

[0092] The spreading box 5 is set as far away from the outlet of the connecting pipe 2 as possible so that the raw material powder particles can obtain a longer residence time in the connecting pipe 2, so that the raw material powder can better contact with the high-temperature gas in the connecting pipe 2, thereby achieving more efficient heat exchange.

[0093] The material scattering box 5 is arranged to be tilted downward. After passing through the material scattering box 5, the material has an initial velocity of downward movement. After entering the connecting pipeline 2, the gas in the connecting pipeline 2 flows upward. Therefore, the material moves in the opposite direction of the airflow located therein in the connecting pipeline 2. After entering the connecting pipeline 2, the material continues to move downward under the action of inertia, and when the gas moves upward, it will generate resistance to the material and disperse the material at the same time. Therefore, the material can achieve further dispersion in the connecting pipeline 2.

[0094] Under the action of gas resistance, the material gradually slows down and eventually decelerates to 0. Then, under the impact force of the gas, it begins to move upward and continues to accelerate until the speed of the material is the same as that of the gas, and finally follows the gas into the next stage heat exchanger.

[0095] This arrangement can extend the residence time of the material in the connecting pipe 2, thereby allowing the material to obtain more heat exchange time. Moreover, since the speed of the material after entering the connecting pipe 2 is often not equal to the speed of the airflow, the material can exchange heat with different high-temperature gases before it can move at the same speed as the airflow, thereby obtaining a better heat exchange effect.

[0096] Preferably, according to the actual production situation, the diameter of the connecting pipe 2 is adjusted so that the wind speed in the connecting pipe 2 is controlled at about 16m / s; at the same time, the distance between the spreading box 5 and the outlet of the connecting pipe 2 is set to 1200-1300mm, so that the raw material powder can stay in the connecting pipe 2 for 4-5s, thereby obtaining a better heat exchange effect.

[0097] In this embodiment, preferably, the material spreading box 5 is further provided with a blowing pipe 84 capable of spraying gas into the material spreading box 5 , the blowing pipe 84 is arranged to be inclined downward, and the outlet of the blowing pipe 84 faces the material spreading plate 82 .

[0098] After long-term use, the material spreading box 5 may become clogged, especially the material channel between the dispersion guide rails 83 is easily clogged. The material spreading box 5 is provided with a blow pipe 84. When the blow pipe 84 is connected to high-pressure gas, the surface of the spreading plate 82 can be cleaned by blowing high-pressure air, thereby clearing the blockage of the spreading plate 82.

[0099] More preferably, by aligning the outlet of the blowing pipe 84 with the material channel between the dispersing guide rails 83 , the material channel between the dispersing guide rails 83 can be reliably cleaned.

[0100] In this embodiment, preferably, a constriction is provided below the connection between the material spreading box 5 of the connecting pipeline 2 and the connecting pipeline 2 .

[0101] A constriction is provided below the connection between the scattering box 5 and the connecting pipe 2, so that the flow velocity of the airflow passing through the constriction will suddenly increase. Subsequently, the gas with increased flow velocity and the material falling through the scattering box 5 will produce a spraying effect. The spraying effect of the airflow can be used to disperse the raw material powder added through the scattering box 5, thereby increasing the degree of mixing of the raw material powder and the airflow, and improving the heat exchange efficiency between the raw material powder and the high-temperature gas.

[0102] Since the material will have a downward movement after entering the connecting pipe 2, a distance should be set between the necking position and the connection between the material box 5 and the connecting pipe 2. This distance should be greater than the downward movement of the material to prevent the material from falling under the necking and collapsing into the connecting pipe 2, and cannot be collected in a timely and effective manner.

[0103] A decomposition furnace system including a preheater device, the decomposition furnace system also includes a decomposition furnace 6, and the air inlet 43 and the discharge port 45 of the preheater device are respectively connected to the decomposition furnace 6;

[0104] Multiple preheater devices are provided, and the multiple preheater devices work independently.

[0105] A plurality of preheater devices are connected to the decomposition furnace and work independently, so that the plurality of preheater devices can perform preheating work at the same time, thereby improving the production efficiency of the preheating system.

[0106] In this embodiment, preferably, the tertiary air inlet 71 of the decomposition furnace 6 is arranged to be inclined downward.

[0107] The tertiary air enters the decomposition furnace along a tangential axis, its rotational direction consistent with the rotational direction of the pulverized coal injection cone. Preferably, the tertiary air duct is tilted downward 10° into the decomposition furnace, so that the tertiary air has a downward velocity component upon entry. Therefore, the tertiary air entry point can be appropriately raised, allowing the tertiary air to still align with the original pulverized coal injection point while maintaining the primary reduction reaction zone within the decomposition furnace. Because the tertiary air entry point is raised, the reduction zone within the decomposition furnace becomes larger, resulting in a longer gas residence time within this zone, which in turn prolongs the duration of the reduction reaction, making the reduction reaction more complete and effective, thereby effectively suppressing the production of nitrogen oxides during pulverized coal combustion.

[0108] Preferably, the residence time of the reduction zone gas is controlled to be greater than 1.8 seconds. Because the gas in this area contains less oxygen, the pulverized coal cannot be fully burned after being added, resulting in the production of a large amount of CO. Under the action of CO, nitrogen oxides are suppressed, and some nitrogen oxides may even be reduced, thereby reducing the nitrogen oxide content in the exhaust gas.

[0109] Preferably, the preheater assembly can also be equipped with a feed branch pipe to allow a portion of the raw meal to reach the lower pulverized coal combustion reduction zone, thereby locally cooling this area. This will further promote the creation of a reducing atmosphere and facilitate the reduction of nitrogen oxides in the kiln exhaust gas. In production operations, if the pulverized coal is fully burned, the pulverized coal feed ratio to the cone of the decomposition furnace can be appropriately increased to ensure that the pulverized coal burns in the reduction zone in the absence of oxygen to create a reducing atmosphere, thereby reducing the large amount of nitrogen oxides in the kiln exhaust gas and achieving a good denitrification effect.

[0110] The location of the smoke chamber feed point is optimized to reduce leakage at the kiln tail. The distance from the smoke chamber slope to the arch is designed to be 2300-2400mm. The effective cross-sectional dimensions of the constriction between the smoke chamber and the calciner cone are 2350×2350mm. The wind speed is controlled at approximately 28.8ms / s.

[0111] The effective capacity of the decomposition furnace is set to 3000m 3 -3200m 3 The gas residence time is increased to about 7.5 seconds. Increasing the furnace capacity is beneficial to improving the system output, and it has better adaptability to system fluctuations, different fuels and raw materials.

[0112] Nano thermal insulation materials can be used in the preheater device to replace calcium silicate boards, further reducing the surface heat loss of the system, improving the energy utilization efficiency of the preheater device, and reducing the heat loss of the preheater device.

[0113] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details of the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0114] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0115] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A preheater device, characterized in that: The preheater device comprises N heat exchangers (11) connected sequentially from bottom to top, wherein the high-temperature flue gas in the decomposition furnace (6) enters from the first heat exchanger (1) at the bottom and is discharged from the Nth heat exchanger (10) at the top, where N is greater than 5; Two adjacent heat exchangers (11) are connected via a connecting pipe (2), the inlet end of the connecting pipe (2) is connected to the air outlet (44) of the heat exchanger (11) located below, and the outlet end of the connecting pipe (2) is connected to the air inlet (43) of the heat exchanger (11) located above; At least two of the heat exchangers (11) located at the top are provided, and a plurality of the heat exchangers (11) are provided in parallel; The preheater device further comprises a feed pipeline (3) and a spreading box (5) for evenly spreading material, wherein the feed pipeline (3) is connected to the connecting pipeline (2) of the Nth heat exchanger (10) through the spreading box (5); the discharge port (45) of the upper heat exchanger (11) of the two adjacent heat exchangers (11) is connected to the connecting pipeline (2) at the air inlet (43) of the lower heat exchanger (11) through the spreading box (5).

2. The preheater device according to claim 1, characterized in that The material spreading box (5) comprises a body, a material spreading inlet (81), a material spreading outlet and a material spreading plate (82), wherein the material spreading inlet (81) is located at the upper part of the body, the material spreading outlet is located at the lower part of the body, and the material spreading outlet is sealedly connected to the connecting pipe (2); The spreading plate (82) is arranged inside the main body, and the spreading plate (82) extends obliquely downward to the spreading outlet, and the cross-sectional width of the spreading plate (82) gradually increases from top to bottom.

3. The preheater device according to claim 2, characterized in that A plurality of dispersion guide rails (83) are provided on the spreading plate (82), and the plurality of dispersion guide rails (83) are located on both sides of the spreading plate (82). The dispersion guide rails (83) on both sides are inclined toward the two side edges of the spreading plate (82), and the dispersion guide rails (83) protrude from the upper surface of the spreading plate (82).

4. The preheater device according to claim 3, characterized in that An auxiliary dispersion guide rail (85) is provided at the lower portion of the spreading plate (82), and the auxiliary dispersion guide rail (85) is located between the dispersion guide rails (83) on both sides, and the auxiliary dispersion guide rail (85) is arranged in a herringbone shape.

5. The preheater device according to claim 4, characterized in that A distance is provided between the upper end of the dispersion guide rail (83) and the upper end of the spreading plate (82).

6. The preheater device according to claim 2, characterized in that A gap is provided between the material spreading box (5) and the outlet of the connecting pipeline (2), and the time for the raw material powder to pass through the gap is 4-5 seconds.

7. The preheater device according to claim 6, characterized in that A constriction is provided below the connection between the material spreading box (5) of the connecting pipeline (2) and the connecting pipeline (2).

8. The preheater device according to claim 2, characterized in that The material spreading box (5) is further provided with a blowing pipe (84) capable of spraying gas toward the material spreading box (5), the blowing pipe (84) being arranged obliquely downward, and the outlet of the blowing pipe (84) facing the material spreading plate (82).

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