A wide channel plate type air preheater with flue gas channel ash cleaning and self-cleaning function

Abstract

The present invention discloses a wide-channel plate-type air preheater with a flue gas channel ash cleaning and self-cleaning function, which belongs to the field of combustion residue treatment, solves the problem of ash accumulation in the air preheater, and the technical solution to solve the problem is mainly a wide-channel plate-type air preheater with a flue gas channel ash cleaning and self-cleaning function, comprising a casing, a plurality of heat exchange plates arranged at intervals along the front and rear directions are connected in the casing, a flue gas channel is formed between two heat exchange plates, the heat exchange plate is formed by welding two front and rear thin plates through a plurality of welding parts, the unwelded parts of the two thin plates are away from each other to form an air flow cavity, the air flow cavity and the welding parts are staggered, at least one welding part on at least one of the heat exchange plates is provided with a rapping rod, one part of the rapping rod is fixedly connected to the welding part, at least one end of the rapping rod has a gap with an adjacent heat exchange plate or an adjacent rapping rod, and the gap is smaller than the shaking amplitude of the heat exchange plate. The present invention is mainly used to solve the problem of ash accumulation in the air preheater.

Description

Technical Field

[0001] The invention relates to the treatment of combustion residue, in particular to a wide-channel plate-type air preheater with smoke channel ash-clearing and self-cleaning functions. Background Art

[0002] Plate air preheater (air preheater) is an important equipment in thermal systems such as industrial boilers and power station boilers. Its main function is to use the waste heat of flue gas in the flue at the tail end of the boiler to heat the air that is about to enter the furnace, thereby improving the thermal efficiency of the boiler and reducing energy consumption. By preheating the air, the fuel can be burned more fully, reducing incomplete combustion losses, improving combustion efficiency, and at the same time reducing the exhaust temperature and heat loss. Among them, the wide flow channel corrugated plate air preheater: the wide flow channel corrugated plate sheet is used to form an external wall corrugated wall plate type and an internal fully transparent wide flow channel plate air preheater. The plate air preheater with a wide flow channel has the advantages of reducing dust accumulation, reducing resistance, and improving heat exchange efficiency. Since the flue gas channel formed between the heat exchange plates of the wide flow channel has a wide spacing, it can reduce the accumulation of dust in the flue gas in the channel, but the dust in the gaps of the heat exchange plates is still easy to accumulate.

[0003] During the combustion process of equipment such as boilers, combustion residues will be generated due to incomplete combustion of fuel and the presence of impurities in the fuel. If these residues are not handled in time, they will gradually accumulate in the air preheater, causing a series of problems: the residues accumulate on the heat exchange surface of the air preheater, forming an insulation layer that hinders the heat transfer between the flue gas and the air. This greatly reduces the heat exchange efficiency of the air preheater, resulting in a decrease in the thermal efficiency of the boiler and an increase in energy waste. For example, in power plant boilers, the decrease in heat exchange efficiency may lead to a decrease in power generation efficiency and increase power generation costs. The accumulation of residues will narrow the flue gas flow channel inside the air preheater, thereby increasing the resistance to flue gas flow. This requires a larger fan power to overcome the resistance, resulting in increased energy consumption, and will also increase the operating cost and maintenance difficulty of the equipment. For example, in industrial boilers, the increase in resistance may cause the fan to be overloaded, affecting the stable operation of the equipment.

[0004] A Chinese patent with publication number CN202123245082.0 mentions a cleaning method in which an ultrasonic generator is installed in the high-temperature steam inlet pipe to enable the soot blower to have a blowing and blocking function during operation. However, this cleaning method can only be used to blow soot at specific positions of specific plates. If the area of ​​the heat exchange plate is too large, a large-scale dust removal effect cannot be achieved. In addition, the wind and dust are mixed with the flue gas during soot blowing, and the cleaning effect is not ideal, so good cleaning cannot be achieved. Summary of the invention

[0005] In order to overcome the disadvantage of easy dust accumulation in the prior art hollow preheater, the present invention provides a wide flow channel plate type air preheater with flue gas channel dust cleaning and self-cleaning function, which can solve the problem of easy dust accumulation in the air preheater.

[0006] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a wide-channel plate-type air preheater with flue gas channel cleaning and self-cleaning functions, comprising a casing, wherein a plurality of heat exchange plates arranged at intervals along the front-to-back direction are connected inside the casing, and a flue gas channel is formed between two of the heat exchange plates, and the heat exchange plates are formed by welding two front and rear thin plates through a plurality of welding parts, and the unwelded parts of the two thin plates are far away from each other to form an air flow cavity, and the air flow cavity and the welding parts are staggered, and at least one welding part on at least one of the heat exchange plates is provided with a rapping rod, and one part of the rapping rod is fixedly connected to the welding part, and there is a gap between at least one end of the rapping rod and an adjacent heat exchange plate or an adjacent rapping rod, and the gap is smaller than the shaking amplitude of the heat exchange plate.

[0007] After adopting the above technical scheme, the present invention has the following advantages: since the flue gas pressure has the characteristic of fluctuation, when the flue gas flows in the flue gas channel, the flow velocity and pressure will be uneven. At the same time, the flue gas flow velocity in the flue gas channel will also change as it passes through the welding part, which is specifically manifested as follows: when the flue gas flows through the unwelded part of the heat exchange plate, the width of the flue gas channel is small, which makes the flow velocity of the flue gas faster. At this time, the width of the air flow cavity corresponding to this part is large, and the flow velocity of the air is slower; and when the flue gas flows through the welding part of the heat exchange plate, the width of the flue gas channel is large, which makes the flow velocity of the flue gas slower. At this time, the width of the air flow cavity corresponding to this part is large, and the flow velocity of the air is slower. The width of the air flow cavity is small and the air flow rate is fast. This situation will cause a pressure difference between the flue gas channel and the air flow cavity. Because the Venturi effect produces different pressures on different parts of the heat exchange plate, in addition, since the heat exchange plate is welded from two thin plates, these pressure differences can cause the thin plates to shake to a certain extent. These shakings make it difficult for dust to accumulate on the outer surface of the heat exchange plate. When the heat exchange plate shakes, the rapping rod fixed on the welding part vibrates the adjacent heat exchange plates as the heat exchange plate shakes, so that even if there is dust accumulation on the heat exchange plate, the dust can be vibrated down by the vibration formed by the rapping rod, and then be carried away with the flow of flue gas.

[0008] Furthermore, the casing is provided with a left connecting part and a right connecting part, and the left and right side surfaces of the heat exchange plate are respectively connected to the left connecting part and the right connecting part, and the distance between the left connecting part and the right connecting part is smaller than the length between the left and right side surfaces of the heat exchange plate, so that the heat exchange plate is connected in a wave shape between the left connecting part and the right connecting part.

[0009] By adopting the above-mentioned technical solution, by setting the distance between the left connecting part and the right connecting part to be smaller than the length between the left and right side surfaces of the heat exchange plate, the heat exchange plate is slightly bent when installed on the casing, and is installed on the casing when it is wavy, so that the shaking amplitude of the heat exchange plate is larger. Since the heat exchange plate has peaks and troughs at the same time, it can better disperse stress compared to a single-wave structure, reduce local stress concentration, and increase the stability of the heat exchange plate.

[0010] Furthermore, at least one of the upper and lower sides of the heat exchange plate is connected to the adjacent heat exchange plate through a flexible material, the flexible material is connected to the middle part of the upper and lower sides of the heat exchange plate, and / or one of the left and right sides of the heat exchange plate is flexibly connected to the shell.

[0011] By adopting the above-mentioned technical solution and adding flexible material connections, the stability of the heat exchange plate is increased when it is shaken, and the connection with the casing is prevented from being disconnected due to excessive shaking, thereby avoiding damage to the structure of the heat exchange plate. When one of the left and right sides is flexibly connected to the casing, the shaking amplitude of the heat exchange plate can be increased. The above-mentioned connection method can be selected according to the size of the heat exchange plate and the usage scenario.

[0012] Furthermore, the flexible material is a semicircular tube, a single heat exchange plate is only connected to one semicircular tube, the semicircular tube is only installed on the side close to the flue gas inflow, and the convex surface of the semicircular tube faces the flue gas inlet.

[0013] By adopting the above-mentioned technical solution, the semicircular tube is flexibly connected to the adjacent heat exchange plate, so that the shaking of the heat exchange plate is more stable, and the protruding surface of the semicircular tube is facing the smoke inlet to reduce the accumulation of dust in the smoke on the semicircular tube.

[0014] Furthermore, a through hole is provided on the welding portion, the middle part of the rapping rod is fixed to the through hole, the rapping rod protrudes from the heat exchange plate in the front-rear direction, and the heat exchange plates with rapping rods and the heat exchange plates without rapping rods are arranged alternately.

[0015] By adopting the above technical solution, the rapping rod passes through the through hole, so that the rapping rod can rapple to two adjacent heat exchange plates when shaking, thereby lengthening the rapping rod, thereby reducing the number of rapping rods and reducing the cost of the air preheater.

[0016] Furthermore, a locking column is installed on the casing, one end of the locking column is fixedly connected to the casing, and the other end of the locking column is abutted against the outermost heat exchange plate or the outermost rapping rod.

[0017] By adopting the above-mentioned technical solution and arranging a locking column on the casing, it is possible to prevent the entire heat exchange plate from shaking too much, thereby avoiding excessive fatigue stress of the plate causing breakage.

[0018] Furthermore, the welding portion includes at least two welding rings of different shapes, and a plurality of welding rings of the same shape are sequentially spaced apart in the direction of flue gas flow.

[0019] By adopting the above-mentioned technical solution, due to the shape of the welding ring on the heat exchange plate, the flue gas will form different degrees of pressure on the heat exchange plate when flowing through parts of different widths of the flue gas channel. In addition, the air interacts with each other when passing through parts of different widths of the air channel, thereby increasing the significant curvature of the heat exchange plate in the direction perpendicular to the flue gas flow. The instability of the flue gas causes the heat exchange plate to shake when bending, thereby increasing the effect of heat exchange that is not easy to accumulate dust.

[0020] Furthermore, the welding portion includes at least two of a circular welding ring, a shuttle welding ring with a small end facing the air flow direction, and a teardrop-shaped welding ring with a small end facing the air inflow direction.

[0021] By adopting the above-mentioned technical scheme, under the condition that the width of the air flow cavity is the same, when the air flows through the shuttle-shaped welding ring, the flow rate of the air flow is avoided to be reduced, so that the subsequent lower temperature air can enter the heat exchange plate faster, thereby increasing the convection and absorption of air heat; when the air flows through the teardrop-shaped welding ring, the air flow is divided when it contacts the small end of the welding ring, and then when passing through the large end of the teardrop shape, the divided air flow forms turbulence at the tail end, so that the internal and external air flows are mixed, so that the air with a lower internal temperature contacts the plate wall, thereby increasing the convection and absorption of air heat; when the air flows through the circular welding ring, the flow rate is relatively slow, so the air flowing through these three welding rings can form different pressures on the heat exchange plate here, which helps to increase the shaking of the heat exchange plate.

[0022] Furthermore, the rapping rod and the welding part are fixed by welding.

[0023] By adopting the above-mentioned technical solution, the rapping rod and the welding part are fixed by welding, and the rapping rod can be welded while the welding process of the welding part is being carried out, thereby reducing the processing steps and lowering the production cost.

[0024] Furthermore, the casing is provided with sound insulation cotton.

[0025] By adopting the above-mentioned technical solution, since the heat exchange plate in the casing will emit a vibration noise during operation, the noise can be reduced by providing sound insulation cotton on the casing.

[0026] The beneficial effect of the present invention is that since the flue gas pressure has the characteristic of fluctuation, when the flue gas flows in the flue gas channel, the flow velocity and pressure will be uneven. At the same time, the flue gas flow velocity in the smoke channel will also change as it passes through the welding part. In addition, since the heat exchange plate is welded from two thin plates, these pressure differences can cause the thin plates to shake to a certain extent. These shakings make it difficult for dust to accumulate on the outer surface of the heat exchange plate. When the heat exchange plate shakes, the rapping rod fixed on the welding part vibrates the adjacent heat exchange plates as the heat exchange plate shakes, so that even if there is dust accumulation on the heat exchange plate, the dust can be vibrated down by the vibration formed by the rapping rod, and then be carried away with the flow of the flue gas. In order to increase the swing amplitude of the heat exchange plate, one of the left and right side surfaces is flexibly connected to the shell, and the distance between the left connecting part and the right connecting part is set to be smaller than the length between the left and right side surfaces of the heat exchange plate, so that the heat exchange plate is slightly bent when installed on the casing, and is installed on the casing when it is wavy, so that the swing amplitude of the heat exchange plate is larger. Due to the periodic swing of the heat exchange plate, peaks and troughs will appear at the same time. Compared with the single-wave structure, it can better disperse the stress, reduce local stress concentration, and increase the stability of the heat exchange plate. In addition, in order to prevent the connection with the casing from being disconnected due to excessive shaking, and to avoid damage to the structure of the heat exchange plate, flexible material connections are added to the upper and lower sides to increase the stability of the heat exchange plate when it swings. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] The present invention will be further described below in conjunction with the accompanying drawings:

[0028] Figure 1 It is a schematic diagram of a wide-channel plate-type air preheater with flue gas channel ash cleaning and self-cleaning function according to the present invention;

[0029] Figure 2 for Figure 1 A front view in the middle C direction;

[0030] Figure 3 for Figure 2 A magnified image of point A;

[0031] Figure 4 for Figure 2 The enlarged view of point B;

[0032] Figure 5 is a schematic diagram of a heat exchange plate;

[0033] Figure 6 for Figure 1 Front view in the D direction.

[0034] Description of the drawings: 1. Casing; 11. Left connecting part; 12. Right connecting part; 2. Heat exchange plate; 21. Welding part; 211. Through hole; 22. Air flow cavity; 3. Smoke channel; 4. Vibrating rod; 5. Semicircular tube; 6. Locking column; 7. Sound insulation cotton. DETAILED DESCRIPTION

[0035] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments.

[0036] The terms "first", "second", etc. (if any) in the specification and claims of the present invention are used to distinguish similar objects, rather than to describe a specific order or sequence. Even if "second" is used to distinguish before a certain technical feature, it does not necessarily indicate that "first" is present. It should be understood that in the present invention, "including" and "having" and any of their variations are intended to cover non-exclusive inclusions. It should be understood that in the present invention, "multiple" refers to two or more. "And / or" is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, X and / or Y can represent: X exists alone, X and Y exist at the same time, and Y exists alone. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "Including X, Y and Z", "Including X, Y, Z" means that X, Y, and Z are all included, "Including X, Y or Z" means that one of X, Y, and Z is included, and "Including X, Y and / or Z" means that any one, any two, or three of X, Y, and Z are included.

[0037] The technical solution of the present invention is described in detail with specific embodiments below. The following specific embodiments can be combined or replaced with each other according to actual conditions, and the same or similar concepts or processes may not be described in detail in some embodiments.

[0038] Example:

[0039] like Figures 1 to 6 As shown, the present invention provides a wide-channel plate-type air preheater with flue gas channel cleaning and self-cleaning functions, including a casing 1, wherein a plurality of heat exchange plates 2 spaced apart along the front-to-back direction are connected inside the casing 1, a flue gas channel 3 is formed between two of the heat exchange plates 2, the heat exchange plate 2 is formed by welding two front and rear thin plates through a plurality of welding portions 21, and the unwelded portions of the two thin plates are away from each other to form an air flow cavity 22, at least one welding portion 21 is provided with a rapping rod 4, one part of the rapping rod 4 is fixedly connected to the welding portion 21, and there is a gap between at least one end of the rapping rod 4 and the adjacent heat exchange plate 2, and the gap is smaller than the shaking amplitude of the heat exchange plate 2.

[0040] After adopting the above technical scheme, the present invention has the following advantages: since the flue gas has the characteristic of fluctuation, when the flue gas flows in the flue gas channel 3, the flow velocity and the air pressure will be uneven. At the same time, the flue gas flow velocity in the flue gas channel 3 will also change as it passes through the welding portion 21, which is specifically manifested as follows: when the flue gas flows through the unwelded portion of the heat exchange plate 2, the width of the flue gas channel 3 is small, which makes the flow velocity of the flue gas faster. At this time, the width of the air flow cavity 22 corresponding to this portion is large, and the air flow velocity in the air flow cavity 22 is slow; and when the flue gas flows through the welding portion 21 of the heat exchange plate 2, the width of the flue gas channel 3 is large, which makes the flow velocity of the flue gas slower. At this time, the air flow cavity 22 corresponding to this portion is large, and the air flow velocity in the air flow cavity 22 is slow. The width of the cavity 22 is small and the air flow rate is fast. This situation will cause a pressure difference between the flue gas channel 3 and the air flow cavity 22. Because the Venturi effect produces different pressures at different locations on the heat exchange plate 2, in addition, since the heat exchange plate 2 is welded from two thin plates, these pressure differences can cause the thin plates to shake to a certain extent. These shakings make it difficult for dust to accumulate on the outer surface of the heat exchange plate 2. When the heat exchange plate 2 shakes, the rapping rod 4 fixed on the welding portion 21 vibrates the adjacent heat exchange plate 2 as the heat exchange plate 2 shakes, so that even if there is dust accumulation on the heat exchange plate 2, the dust can be vibrated off by the vibration formed by the rapping of the rapping rod 4, and then be taken away with the flow of the flue gas.

[0041] Preferably, flue gas circulates in the upper and lower directions of the casing 1, and the flue gas transfers heat to the cold air in the air flow cavity 22 when passing through the flue gas channel 3 in the casing 1. Therefore, the top of the casing 1 is connected to the flue gas inlet pipe, and the bottom of the casing 1 is connected to the flue gas outlet pipe. The air in the heat exchange plate 2 flows from left to right. Therefore, the leftmost side of the single heat exchange plate 2 is connected to the air inlet pipe, and the rightmost side is connected to the air outlet pipe, so that when the air enters the heat exchange plate, it reduces the flow in other directions and mainly flows to the right. After flowing through the heat exchange plate, heat exchange is generated with the flue gas between the heat exchange plates, and the temperature in the high-temperature flue gas is transferred to the low-temperature air, so that the air is preheated before entering the combustion furnace.

[0042] Specifically, the edge positions of the two thin plates are also sealed by welding, the leftmost air flow cavity 22 of the single heat exchange plate 2 is connected to the air inlet pipe for the incoming air, and the rightmost air flow cavity 22 is connected to the air outlet pipe for the outgoing air, so that the air flow cavity 22 is formed inside; the shaking amplitude mentioned in the present application refers to the amplitude of the front and rear fluctuation of the heat exchange plate 2 relative to the casing 1; the forming methods of the heat exchange plate 2 include mold forming and fluid forming, and the mold forming is to cast the two thin plates of the heat exchange plate 2 into a predetermined shape through a mold, and then weld the two plates together at the welding part 21; and fluid forming is to first weld two straight thin plates together at the welding part 21 by laser non-oxidation welding, and then seal the air outflow port, and fill the air inlet with high-pressure gas or high-pressure liquid to make the ventilation part of the thin plate bulge to form the predetermined shape of the heat exchange plate 2.

[0043] In another embodiment, two adjacent heat exchange plates 2 have the same shape, and the middle position of the rapping rod 4 is fixed to the welding portion 21 , so when the rapping rod 4 shakes with the heat exchange plate 2 , the rapping rod 4 will collide and vibrate with the adjacent rapping rod 4 .

[0044] When producing and processing the heat exchange plate 2, wide channel laser plate bulging is adopted, and the welding point spacing and bulging height are reasonably arranged, so that the angle between the entire corrugated surface and the flue gas scouring is much larger than the self-locking angle of the dust, effectively preventing dust deposition.

[0045] A plurality of heat exchange plates 2 are arranged as vertical wall panels in the casing 1, and the spacing between adjacent heat exchange plates 2 is reasonably arranged. The entire flue is divided into a number of relatively independent small flue gas channels 3. The entire air preheater is equivalent to a rectifying grid. At the same time, the flue gas flow field and the flue gas velocity are relatively uniform, which reduces the formation of ash accumulation from the structural point of view.

[0046] The air inlet and outlet of the multiple heat exchange plates 2 are open corrugated plates to absorb the tensile stress generated by vibration and prevent fatigue cracking, etc. A non-rigidly connected support is set at the bottom to bear the weight of the plates.

[0047] Further, such as Figure 6 As shown, the casing 1 is provided with a left connecting portion 11 and a right connecting portion 12, and the left and right side surfaces of the heat exchange plate 2 are respectively connected to the left connecting portion 11 and the right connecting portion 12, and the distance between the left connecting portion 11 and the right connecting portion 12 is smaller than the length between the left and right side surfaces of the heat exchange plate 2, so that the heat exchange plate 2 is connected between the left connecting portion 11 and the right connecting portion 12 in a wave shape.

[0048] By adopting the above-mentioned technical solution, by setting the distance between the left connecting part 11 and the right connecting part 12 to be smaller than the length between the left and right side surfaces of the heat exchange plate 2, the heat exchange plate 2 is slightly bent when installed on the casing 1, and is installed on the casing 1 when it is wavy, so that the shaking amplitude of the heat exchange plate 2 is larger. Since the heat exchange plate 2 has peaks and troughs at the same time, it can better disperse stress compared with a single-wave structure, reduce local stress concentration, and increase the stability of the heat exchange plate 2.

[0049] It can be understood that in another embodiment, the distance between the left connecting portion 11 and the right connecting portion 12 is equal to the length between the left and right side surfaces of the heat exchange plate 2 .

[0050] Furthermore, at least one of the upper and lower sides of the heat exchange plate 2 is connected to the adjacent heat exchange plate 2 through a flexible material, the flexible material is connected to the middle part of the upper and lower sides of the heat exchange plate 2, and / or one of the left and right sides of the heat exchange plate 2 is flexibly connected to the shell.

[0051] By adopting the above technical solution and adding a flexible material connection, the heat exchange plate 2 is made more stable when shaking, and the connection with the casing 1 is prevented from being disconnected due to excessive shaking, thereby avoiding damage to the structure of the heat exchange plate 2.

[0052] It is understandable that the left and right sides of the heat exchange plate 2 can also be flexibly connected to the casing 1. At this time, the channels for air inflow and outflow also need to be designed to be flexible to cooperate with the shaking of the heat exchange plate 2. This design can increase the shaking amplitude of the heat exchange plate 2.

[0053] Furthermore, the flexible material is a semicircular tube 5, a single heat exchange plate 2 is only connected to one semicircular tube 5, the semicircular tube 5 is only installed on the side close to the flue gas inflow, and the convex surface of the semicircular tube 5 faces the flue gas inlet.

[0054] By adopting the above technical solution, the semicircular tube 5 is flexibly connected to the adjacent heat exchange plate 2, so that the shaking of the heat exchange plate 2 is more stable, and the convex surface of the semicircular tube 5 is facing the smoke inlet to reduce the accumulation of dust in the smoke on the semicircular tube.

[0055] Specifically, the same heat exchange plate can be flexibly connected to two adjacent heat exchange plates using two semicircular tubes, but the two semicircular tubes need to be staggered to prevent dust accumulation at the junction; the outermost heat exchange plate 2 can also be flexibly connected to the shell through half of the semicircular tube.

[0056] It is understandable that the flexible material may also be a material having a certain strength and capable of flexible connection, such as memory alloy.

[0057] Furthermore, a through hole 211 is provided on the welding portion 21, and the middle part of the rapping rod 4 is fixed to the through hole 211. The rapping rod 4 protrudes from the heat exchange plate 2 in the front-to-back direction, and the heat exchange plates 2 with rapping rods 4 and the heat exchange plates 2 without rapping rods 4 are arranged alternately.

[0058] By adopting the above-mentioned technical solution, the rapping rod 4 passes through the through hole 211, so that the rapping rod 4 can rapple to two adjacent heat exchange plates 2 when shaking, thereby being able to lengthen the length of a single rapping rod 4, and being able to reduce the number of rapping rods 4 installed on other heat exchange plates, thereby being able to reduce the number of rapping rods 4, reducing the processing time, and reducing the cost of the air preheater.

[0059] It can be understood that, except for the two ends of the rapping rod 4, the rest are all middle parts.

[0060] Furthermore, a locking column 6 is installed on the casing 1 , one end of the locking column 6 is fixedly connected to the casing 1 , and the other end of the locking column 6 abuts against the outermost heat exchange plate 2 or the outermost rapping rod 4 .

[0061] By adopting the above-mentioned technical solution, by arranging the locking column 6 on the casing 1, it is possible to prevent the entire heat exchange plate 2 from shaking too much, thereby avoiding excessive fatigue stress of the plate to cause breakage.

[0062] Preferably, the locking column 6 is installed in the middle of the heat exchange plate 2 to achieve the best effect.

[0063] Furthermore, the welding portion 21 includes at least two welding rings of different shapes, and a plurality of welding rings of the same shape are sequentially spaced apart in the flue gas flow direction.

[0064] By adopting the above-mentioned technical solution, due to the shape of the welding ring on the heat exchange plate 2, the flue gas will form different degrees of pressure on the heat exchange plate 2 when flowing through parts of different widths of the flue gas channel 3. At this time, the air interacts with each other when flowing through different parts of the air channel, thereby increasing the significant curvature of the heat exchange plate 2 in the direction perpendicular to the flue gas flow, and the instability of the flue gas causes the heat exchange plate 2 to shake when bending, thereby increasing the effect of heat exchange that is not easy to accumulate dust.

[0065] It can be understood that welding rings with different shapes or sizes have different effects on the air flow rate, and therefore can be understood as different definitions of shapes in this solution.

[0066] Furthermore, the welding portion 21 includes at least two of a circular welding ring, a shuttle welding ring with a small end facing the air flow direction, and a teardrop-shaped welding ring with a large end facing the air inflow direction.

[0067] By adopting the above-mentioned technical scheme, when the width of the air flow cavity 22 is the same, when the air flows through the shuttle-shaped welding ring, it can comb the airflow while avoiding reducing the flow rate of the airflow, so that the subsequent lower temperature air can enter the heat exchange plate 2 faster, thereby increasing the convection and absorption of air heat; when the air flows through the teardrop-shaped welding ring, the airflow is cut when it contacts the small end of the welding ring, and then when passing through the large end of the teardrop shape, the cut airflow forms turbulence at the tail end, so that the internal and external airflows are mixed, so that the air with a lower internal temperature contacts the plate wall, thereby increasing the convection and absorption of air heat; when the air flows through the circular welding ring, the flow rate is relatively slow, so the air flowing through these three welding rings can form different pressures on the heat exchange plate 2 here, which helps to increase the shaking of the heat exchange plate 2.

[0068] It can be understood that in addition to the above three welding rings, there are also welding rings of other shapes, as long as the air in the air flow cavity can be combed and changed in speed after flowing through the welding ring.

[0069] Furthermore, the rapping rod 4 and the welding portion 21 are fixed by welding.

[0070] By adopting the above-mentioned technical solution, the rapping rod 4 and the welding part 21 are fixed by welding, and the rapping rod 4 can be welded while the welding process of the welding part 21 is being carried out, thereby reducing the processing steps and lowering the production cost.

[0071] It is understandable that the rapping rod 4 can also be fixedly connected to the welding portion 21 by means of nail gun fixation.

[0072] Furthermore, the housing 1 is provided with sound insulation cotton 7.

[0073] With the aforementioned technical solution, since the heat exchange plate 2 in the casing 1 will emit a vibration noise during operation, the casing 1 is provided with a sound insulation cotton 7 to reduce the noise.

[0074] It is understandable that other materials with sound insulation effect can be installed on the casing 1 to reduce the noise inside the casing 1. The sound insulation cotton 7 can be wrapped around the outer periphery of the casing 1 or installed inside the casing 1. If the casing 1 is hollow with a interlayer, it can also be placed in the interlayer.

[0075] When the present embodiment is in use, smoke flows in the up and down directions of the casing 1, and the smoke exchanges heat with the cold air in the air flow cavity 22 when passing through the smoke channel 3 in the casing 1. Therefore, the top of the casing 1 is connected to the smoke inlet pipe, and the bottom of the casing 1 is connected to the smoke outlet pipe. The air in the heat exchange plate 2 flows from left to right. Therefore, the leftmost air flow cavity of the single heat exchange plate 2 is connected to the air inlet pipe of the incoming air, and the rightmost air flow cavity is connected to the air outlet pipe of the outgoing air, so that when the air enters the heat exchange plate, it reduces the flow in other directions and mainly flows to the right. After flowing through the heat exchange plate, heat exchange is generated with the smoke between the heat exchange plates, and the temperature in the high-temperature smoke is absorbed into the low-temperature air, so that the air is preheated before entering the combustion furnace. At the same time, the dust carried in the flue gas will accumulate in the grooves and gaps of the heat exchange plates. However, since the heat exchange plates are formed by welding thin plates, when the flue gas pressure fluctuates, the heat exchange plates will shake, driving the rapping rods at the welding parts to rappel the dust on the adjacent heat exchange plates, which will then be carried away in the downward flow of the flue gas. This has a better dust removal effect than flue gas flowing in other directions, making it less likely for dust to accumulate on the heat exchange plates, avoiding heat insulation caused by dust accumulation, and not reducing heat transfer, thereby achieving better heat exchange function.

[0076] The installation process is as follows: first use compression molding to manufacture the heat exchange plate, first cast the two thin plates of the heat exchange plate 2 into a predetermined shape through a mold, and then weld the two plates together on the welding part 21 to form a heat exchange plate, and at the same time, synchronously weld the rapping rod to the welding part by welding, and then weld all the heat exchange plates to the casing, and then connect the heat exchange plate with the air inlet and outlet pipes, and finally wrap the silencer cotton on the outside of the casing to complete the installation.

[0077] In addition to the above-mentioned preferred embodiments, the present invention also has other implementation modes. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative work are within the scope of protection requested by the present invention.

Claims

1. A wide-channel plate-type air preheater with flue gas channel cleaning and self-cleaning function, comprising a casing, wherein a plurality of heat exchange plates arranged in a front-to-back direction are connected inside the casing, and a flue gas channel is formed between two of the heat exchange plates, characterized in that: The heat exchange plate is formed by welding two front and rear thin plates through a plurality of welding parts, and the unwelded parts of the two thin plates are away from each other to form an air flow cavity, and the air flow cavity and the welding parts are staggered. At least one welding part on at least one of the heat exchange plates is provided with a rapping rod, and the rapping rod is fixedly connected to the welding part. There is a gap between one end of the rapping rod and the adjacent heat exchange plate, and the gap is smaller than the shaking amplitude of the heat exchange plate, so that the shaking of the heat exchange plate drives the rapping rod at the welding part to vibrate the adjacent heat exchange plate. The casing is provided with a left connecting part and a right connecting part. The left and right side surfaces of the heat exchange plate are respectively connected to the left connecting part and the right connecting part, and the distance between the left connecting part and the right connecting part is smaller than the length between the left and right side surfaces of the heat exchange plate, so that the heat exchange plate is connected between the left connecting part and the right connecting part in a wave shape to increase the shaking amplitude of the heat exchange plate; at least one side of the upper and lower side surfaces of the heat exchange plate is connected to the adjacent heat exchange plate through a flexible material, and the flexible material is connected to the middle part of the upper and lower side surfaces of the heat exchange plate, and / or one side of the left and right side surfaces of the heat exchange plate is flexibly connected to the shell.

2. A wide channel plate type air preheater with flue gas channel ash cleaning and self-cleaning function according to claim 1, characterized in that: The flexible material is a semicircular tube, which is installed only on the side close to the smoke inflow, and the convex surface of the semicircular tube faces the smoke inlet.

3. The wide-channel plate-type air preheater with flue gas channel ash cleaning and self-cleaning function according to claim 1, characterized in that: The welding portion is provided with a through hole, the middle portion of the rapping rod is fixed to the through hole, the rapping rod protrudes from the heat exchange plate in the front-to-back direction, and the heat exchange plate with the rapping rod and the heat exchange plate without the rapping rod are arranged alternately.

4. The wide-channel plate-type air preheater with flue gas channel ash cleaning and self-cleaning function according to claim 1, characterized in that: A locking column is installed on the casing, one end of the locking column is fixedly connected to the casing, and the other end is abutted against the outermost heat exchange plate or the outermost rapping rod.

5. The wide channel plate type air preheater with flue gas channel ash cleaning and self-cleaning function according to claim 1, characterized in that: The welding portion comprises at least two welding rings of different shapes, and a plurality of welding rings of the same shape are sequentially spaced apart in the direction of flue gas flow.

6. A wide channel plate type air preheater with flue gas channel ash cleaning and self-cleaning function according to claim 5, characterized in that: The welding portion includes at least two of a circular welding ring, a shuttle welding ring with a small end facing the air flow direction, and a teardrop-shaped welding ring with a small end facing the air inflow direction.

7. The wide channel plate type air preheater with flue gas channel ash cleaning and self-cleaning function according to claim 1, characterized in that: The rapping rod and the welding part are fixed by welding.

8. The wide-channel plate-type air preheater with flue gas channel ash cleaning and self-cleaning function according to claim 1, characterized in that: The casing is provided with sound insulation cotton.

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