Exhaust gas heat recovery system

Abstract

The invention relates to a waste gas heat recovery system, which belongs to the technical field of waste gas heat treatment, and comprises a heat insulation box, a waste gas inlet and a waste gas outlet are arranged on two corresponding sides of the heat insulation box, a heat exchange assembly is arranged in the heat insulation box, and the heat exchange assembly comprises more than three sets of heat exchangers. More than three sets of heat exchangers are transversely arranged between the waste gas inlet and the waste gas outlet in sequence in rows, each set of heat exchanger is provided with a plurality of fresh air pipes, all the fresh air pipes are vertically arranged in the waste gas channel, the periphery of each fresh air pipe is provided with an air passing gap for waste gas to pass through, and the fresh air pipes of any heat exchanger in the middle are divided into two groups; the bottom openings of the two sets of fresh air pipes communicate with each other, the top openings of the two sets of fresh air pipes communicate with the top openings of all or one set of fresh air pipes of the heat exchangers on the two adjacent sides correspondingly, cleaning is more convenient, and the heat exchange speed is higher.

Description

Technical Field

[0001] The invention belongs to the technical field of waste gas treatment, and in particular relates to a waste gas heat recovery system. Background Art

[0002] Traditional exhaust gas heat recovery systems often adopt a heat exchange layout in which hot exhaust gas flows inside the pipe and cold fresh air flows outside the pipe. The oil stains and impurities carried by the hot exhaust gas remain inside the pipe, making it inconvenient to clean. Summary of the invention

[0003] The invention discloses an exhaust gas heat recovery system which is convenient for cleaning a new air duct.

[0004] For this reason, the present invention adopts the following technical scheme:

[0005] An exhaust gas heat recovery system includes an insulation box, which is open on both sides so that the openings on both sides form an exhaust gas inlet and an exhaust gas outlet respectively, and the interior of the box becomes an exhaust gas channel. A heat exchange assembly is arranged in the insulation box, and the heat exchange assembly includes more than three sets of heat exchangers, which are arranged in a row horizontally between the exhaust gas inlet and the exhaust gas outlet. Each set of heat exchangers has a number of fresh air ducts, all of which are erected in the exhaust gas channel, and each fresh air duct has a wind gap around it for the exhaust gas to pass through. The fresh air ducts of any heat exchanger located in the middle are divided into two groups, the bottoms of the two groups of fresh air ducts are connected to each other, and the tops of the two groups of fresh air ducts are respectively connected to the tops of all or one group of fresh air ducts of the heat exchangers on the adjacent two sides, so that the fresh air ducts of more than three sets of heat exchangers form a continuous fresh air channel, and the fresh air can pass through the fresh air ducts of the heat exchangers on both sides once and pass through the fresh air duct of the heat exchanger in the middle twice.

[0006] As a preferred solution, each set of heat exchanger also includes an upper fresh air box and a lower fresh air box. The upper fresh air box is fixedly arranged on the top wall of the heat insulation box, and the lower fresh air box is arranged below the upper fresh air box and fixedly connected to the upper fresh air box through a connecting rod; a number of fresh air ducts are uprightly arranged between the upper fresh air box and the lower fresh air box, and the top openings are connected to the upper fresh air box, and the bottom openings are connected to the lower fresh air box.

[0007] As a preferred solution, the heat exchanger includes four sets, and the upper fresh air boxes of any two adjacent sets of heat exchangers are fixedly connected and interconnected through a connecting box to connect the four sets of heat exchangers into one set of heat exchange assembly.

[0008] As a preferred solution, the fresh air duct of the heat exchanger close to the exhaust gas outlet is divided into two rows, one row close to the exhaust gas outlet and the other row close to the exhaust gas inlet. The upper fresh air box of the heat exchanger is horizontally divided into a first chamber and a second chamber. The first chamber is located on the exhaust gas outlet side and connected to the row of fresh air ducts of the heat exchanger close to the exhaust gas outlet, and the second chamber is located on the exhaust gas inlet side and connected to the other row of fresh air ducts of the heat exchanger close to the exhaust gas inlet.

[0009] As a preferred solution, the fresh air duct of the heat exchanger close to the exhaust gas inlet is divided into two rows, one row close to the exhaust gas outlet and the other row close to the exhaust gas inlet. The upper fresh air box of the heat exchanger is horizontally divided into a third chamber and a fourth chamber. The third chamber is located on the side of the exhaust gas outlet and connected to the row of fresh air ducts of the heat exchanger close to the exhaust gas outlet. The fourth chamber is located on the side of the exhaust gas inlet and connected to the other row of fresh air ducts of the heat exchanger close to the exhaust gas inlet.

[0010] As a preferred solution, the first chamber is connected to the upper fresh air box closest to the exhaust gas outlet, the second chamber is connected to the third chamber, and the fourth chamber is connected to the upper fresh air box closest to the exhaust gas inlet.

[0011] As a preferred solution, the lower fresh air box of the heat exchanger closest to the exhaust gas inlet is provided with a cool fresh air inlet, and the lower fresh air box of the heat exchanger closest to the exhaust gas outlet is provided with a hot fresh air outlet, so that the flow directions of the exhaust gas and the fresh air are opposite.

[0012] As a preferred solution, all fresh air ducts are oval flat tubes and have narrow arc surfaces as exhaust gas windward surfaces.

[0013] As a preferred solution, the exhaust gas inlet is connected to a secondary filter unit, which includes a secondary filter box fixedly connected to the insulation box and connected to the exhaust gas inlet, and an air equalizing net and a secondary manual filter net are arranged inside the secondary filter box.

[0014] As a preferred solution, the secondary filter box is connected to the primary filter part, the primary filter part includes a primary filter box fixedly connected and connected to the secondary filter box, a 28-mesh rotating filter screen disk is provided inside the primary filter box, the 28-mesh rotating filter screen disk is connected to a motor for driving it to rotate, and a steam pipe for spraying steam toward the screen surface and a water pipe for spraying water toward the screen surface are provided on the side of the 28-mesh rotating filter screen disk.

[0015] The present invention adopts a heat exchange layout in which cool fresh air flows inside the fresh air duct and hot exhaust gas flows outside the fresh air duct. The oil stains and impurities carried by the hot exhaust gas will only adhere to the outer wall of the fresh air duct and will not remain inside the fresh air duct, making it more convenient to clean the fresh air duct; secondly, the fresh air ducts of the present invention are all arranged upright, and the oil stains and dirt can be directly washed away by flushing the outer wall of the fresh air duct without disassembling the fresh air duct to flush the inside of the pipe; thirdly, the fresh air ducts of the present invention all adopt flat tubes, which is beneficial to increasing the heat exchange speed between hot exhaust gas and cool fresh air. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 External view of the overall structure of the exhaust gas heat recovery system disclosed in the present invention

[0017] Figure 2 This is a schematic diagram of the heat exchange assembly structure disclosed in the present invention;

[0018] Figure 3 A longitudinal cross-sectional view of the exhaust gas heat recovery system disclosed in the present invention

[0019] Figure 4 A transverse cross-sectional view of the exhaust gas heat recovery system disclosed in the present invention

[0020] Figure 5 Schematic diagram of the new air duct structure disclosed in the present invention DETAILED DESCRIPTION

[0021] The present invention is described below in conjunction with the accompanying drawings and specific embodiments.

[0022] like Figure 1-5 The exhaust gas heat recovery system shown in the figure comprises an insulation box 10, the insulation box 10 is opened on both sides so that the openings on both sides respectively form an exhaust gas inlet 10.1 and an exhaust gas outlet 10.2, and the interior thereof becomes an exhaust gas channel for the exhaust gas to pass through; the exhaust gas inlet 10.1 is connected to a secondary filter unit 30, the secondary filter unit 30 comprises a secondary filter box 31 fixedly connected to the insulation box 10 and connected to the exhaust gas inlet 10.1, and an air distribution net 32 ​​and a secondary manual filter net 33 are arranged inside the secondary filter box 31; The first-stage filter box 31 is connected to the first-stage filter part 40, and the first-stage filter part 40 includes the first-stage filter box 41 which is fixedly connected and connected to the second-stage filter box 31. A 28-mesh filter screen disk 42 is rotatably provided inside the first-stage filter box 41. The 28-mesh filter screen disk 42 is connected to a motor 43 for driving the rotation thereof. A steam pipe for spraying steam toward the screen surface and a water pipe for spraying water toward the screen surface are provided on the side of the 28-mesh filter screen disk 42. The first-stage filter box 41 is connected to the exhaust gas inlet box 50, and the exhaust gas outlet is connected to the exhaust gas outlet box 60.

[0023] A heat exchange assembly 20 is provided in the heat insulation box 10, and the heat exchange assembly 20 includes four sets of heat exchangers 21. Each set of heat exchangers 21 includes an upper fresh air box 21.1, a lower fresh air box 21.2 and a plurality of fresh air ducts 21.3. The upper fresh air box 21.1 is fixedly arranged on the top wall of the heat insulation box 10, the lower fresh air box 21.2 is arranged below the upper fresh air box 21.1 and are fixedly connected to each other as a whole through a connecting rod 21.4, and a plurality of fresh air ducts 21.3 are vertically arranged between the upper fresh air box 21.1 and the lower fresh air box 21.2, and the top openings are connected to the upper fresh air box 21.1, and the bottom openings are connected to the lower fresh air box 21.2.

[0024] Four sets of heat exchangers 21 are arranged in a row horizontally between the exhaust gas inlet 10.1 and the exhaust gas outlet 10.2, so that all the fresh air pipes 21.3 are erected in the exhaust gas channel. The fresh air pipes 21.3 of each set of heat exchangers 21 are divided into two rows, one row is close to the exhaust gas outlet 10.2, and the other row is close to the exhaust gas inlet 10.1. The two rows of fresh air pipes 21.3 of the same set of heat exchangers 21 are arranged horizontally staggered, and the same row of fresh air pipes 21.3 of the same set of heat exchangers 21 are arranged horizontally at a distance, so that each fresh air pipe 21.3 has a wind gap around it for the exhaust gas to pass through. All fresh air pipes 21.3 are elliptical flat pipes and have narrow arc surfaces as the exhaust gas windward surface, so that the fresh air flowing through the fresh air pipe 21.3 can exchange heat more fully and quickly with the exhaust gas flowing outside the fresh air pipe 21.3, and less oil stains and impurities carried by the exhaust gas remain on the outer wall of the fresh air pipe 21.2.

[0025] Any two adjacent upper fresh air boxes 21 . 1 are fixedly connected and communicated with each other via a connecting box 22 , so that four sets of heat exchangers 21 are fixedly connected to form a set of heat exchange assembly 20 .

[0026] The lower fresh air box 21.2 closest to the warm exhaust gas outlet 10.2 is provided with a cool fresh air inlet, which is connected to the centrifugal blower 70, and the lower fresh air box 21.2 closest to the exhaust gas inlet 10.1 is provided with a hot fresh air outlet, which is connected to the fresh air discharge box 80. This design can make the exhaust gas and the fresh air flow directions in the insulation box 10 opposite, so that the coolest fresh air that has just entered the heat exchange assembly 20 can exchange heat with the hottest exhaust gas that has just entered the insulation box 10, thereby accelerating the heat exchange speed.

[0027] The upper fresh air box 21.1 next to the warm exhaust gas outlet 10.2 is laterally partitioned into a second chamber 21.12 by a first partition 23. The first chamber 21.11 is located on one side of the warm exhaust gas outlet 10.2 and is connected to a row of fresh air pipes 21.3 of the same set of heat exchangers 21 next to the warm exhaust gas outlet 10.2. The second chamber 21.12 is located on one side of the exhaust gas inlet 10.1 and is connected to a row of fresh air pipes 21.3 of the same set of heat exchangers 21 next to the exhaust gas inlet 10.1. The upper fresh air box 21.1 next to the exhaust gas inlet 10.1 is laterally partitioned into a third chamber 21.13 and a fourth chamber 21.14 by a second partition 24. The third chamber 21.13 is located on one side of the warm exhaust gas outlet 10.2 and is connected to a row of fresh air pipes 21.3 of the same set of heat exchangers 21 next to the exhaust gas inlet 10.1. A row of fresh air pipes 21.3 near the warm exhaust gas outlet 10.2, the fourth chamber 21.14 is located on the side of the exhaust gas inlet 10.1 and is connected to the row of fresh air pipes 21.3 of the same set of heat exchangers 21 near the exhaust gas inlet 10.1; the first chamber 21.11 is connected to the upper fresh air box 21.1 closest to the warm exhaust gas outlet 10.2, the second chamber 21.12 is connected to the third chamber 21.3, and the fourth chamber 21.4 is connected to the upper fresh air box 21.1 closest to the exhaust gas inlet 10.1, so that the fresh air can pass through the heat exchanger 21 closest to the warm exhaust gas outlet 10.2 upward at one time, pass through the two sets of heat exchangers 21 in the middle twice, first downward and then upward, and pass through the heat exchanger 21 closest to the exhaust gas inlet 10.1 downward at one time. In this solution, the fresh air ducts 21.3 of the two sets of heat exchangers 21 in the middle are configured as double channels for the fresh air to pass twice, thereby extending the distance of the fresh air passing through the heat insulation box 10 so that the fresh air can more fully absorb the heat of the hot exhaust gas.

[0028] In order to facilitate the cleaning of the oil stains and impurities remaining on the outer wall of the fresh air pipe 21.3, a high-pressure cleaning nozzle 25 for flushing the outer walls of all the fresh air pipes 21.3 of the heat exchanger 21 is provided on the exhaust gas inlet side and the exhaust gas outlet side of each set of heat exchangers 21. The high-pressure cleaning nozzle 25 is provided on the water pipe, which is horizontally arranged in the heat insulation box 10. The water pipe can be provided with two types of cold water pipes and hot water pipes. The high-pressure cleaning nozzle 25 provided on the hot water pipe can first spray hot water to the outer wall of the fresh air pipe 21.3 to soften the grease and impurities, and then the high-pressure cleaning nozzle 25 provided on the cold water pipe can spray cold water to the outer wall of the fresh air pipe 21.3 to flush away the grease and other impurities. For this purpose, a water receiving tank 90 can be provided at the bottom of the heat insulation box 10 to collect the waste water generated when the four sets of heat exchangers 21 are working or cleaning.

[0029] When in use, the exhaust gas inlet box 50 is connected to the discharge end of the exhaust gas generating equipment, the exhaust gas outlet box 60 is connected to the exhaust gas exhaust fan, the air inlet end of the centrifugal blower 70 is connected to the outside, and the fresh air outlet box 80 is connected to the equipment or place that needs to use hot fresh air. At the same time, the exhaust gas exhaust fan and the centrifugal blower 70 are started, and the exhaust gas flows through the inside of the heat insulation box 10 after being filtered by the primary filter box 40 and the secondary filter box 30 along the exhaust gas inlet box 50, and heat exchanges with the cool fresh air flowing through the fresh air pipe 21.3. The warm exhaust gas with residual heat after the heat exchange can be transported to other exhaust gas treatment equipment by the exhaust gas exhaust fan, and the hot fresh air formed after the heat exchange is transported to the use place or equipment by the hot fresh air outlet box 80.

[0030] like Figure 3 As shown by the dotted arrow in the figure, the fresh air flow direction is as follows: the cool fresh air from the outside is first blown into the lower fresh air box 21.2 of the heat exchanger 21 closest to the exhaust gas outlet 10.2 by the centrifugal blower 70, and then goes up along the two rows of fresh air pipes 21.3 of the heat exchanger 21 to enter the upper fresh air box 21.1 of the heat exchanger 21, and then flows downward through the connecting box 22 and the first chamber 21.11 through the row of fresh air pipes 21.3 of the heat exchanger 21 closest to the warm exhaust gas outlet 10.2 and enters the lower fresh air box 21.2 of the heat exchanger 21, and then goes up through the heat exchanger 21. Another row of fresh air pipes 21.3 of the heat exchanger 21 enters the second chamber 21.12 and the third chamber 21.13, then passes downward through a row of fresh air pipes 21.3 of the heat exchanger 21 closest to the exhaust gas inlet 10.1 to enter the lower fresh air box 21.2 of the heat exchanger 21, and passes upward through another row of fresh air pipes 21.3 of the heat exchanger 21 to enter the fourth chamber 21.14, and finally enters the lower fresh air box 21.2 of the heat exchanger 21 along all the fresh air pipes 21.3 of the heat exchanger 21 closest to the exhaust gas inlet 10.1, and is drawn out by the centrifugal blower 80. In the above process, the fresh air flowing through the four sets of heat exchangers 21 can undergo six heat exchanges with the exhaust gas flowing through the heat insulation box 10, which is beneficial to improving the waste heat utilization rate of the exhaust gas.

Claims

1. An exhaust gas heat recovery system, comprising an insulation box (10), the insulation box (10) being split on both sides so that the openings on both sides respectively form an exhaust gas inlet (10.1) and an exhaust gas outlet (10.2), and the interior of the insulation box becomes an exhaust gas channel, characterized in that: A heat exchange assembly (20) is provided in the heat insulation box (10), and the heat exchange assembly (20) includes more than three sets of heat exchangers (21). The more than three sets of heat exchangers (21) are arranged in a row in a horizontal direction between the exhaust gas inlet (10.1) and the exhaust gas outlet (10.2). Each set of heat exchangers (21) includes a plurality of fresh air pipes (21.3). All the fresh air pipes (21.3) are erected in the exhaust gas channel. A wind gap is reserved around each fresh air pipe (21.3) for the exhaust gas to pass through. The fresh air pipe (21.3) of any heat exchanger (21) located in the middle is The two groups of fresh air pipes (21.3) are divided into two groups, the bottom openings of the two groups of fresh air pipes (21.3) are connected to each other, and the top openings of the two groups of fresh air pipes (21.3) are respectively connected to the top openings of all or one group of fresh air pipes (21.3) of the heat exchangers (21) on the adjacent two sides, so that the fresh air pipes (21.3) of more than three sets of heat exchangers (21) form a continuous fresh air channel, and the fresh air can pass through the fresh air pipes (21.3) of the heat exchangers (21) on both sides once and pass through the fresh air pipe (21.3) of the heat exchanger (21) in the middle twice.

2. The exhaust gas heat recovery system according to claim 1, characterized in that: Each set of heat exchangers (21) further comprises an upper fresh air box (21.1) and a lower fresh air box (21.2); the upper fresh air box (21.1) is fixedly arranged on the inner top wall of the heat insulation box (10); the lower fresh air box (21.2) is arranged below the upper fresh air box (21.1) and is fixedly connected to the upper fresh air box (21.1) via a connecting rod (21.4); a plurality of fresh air ducts (21.3) are vertically arranged between the upper fresh air box (21.1) and the lower fresh air box (21.2); the top openings are all connected to the upper fresh air box (21.1), and the bottom openings are all connected to the lower fresh air box (21.2).

3. The exhaust gas heat recovery system according to claim 2, characterized in that: The heat exchangers (21) include four sets, and the upper fresh air boxes (21.1) of any two adjacent sets of heat exchangers (21) are fixedly connected and communicated with each other via a connecting box (22), so that the four sets of heat exchangers (21) are connected to form a heat exchange assembly (20).

4. The exhaust gas heat recovery system according to claim 3, characterized in that: The fresh air pipe (21.3) of the heat exchanger (21) close to the exhaust gas outlet (10.2) is divided into two rows, one row is close to the exhaust gas outlet (10.2), and the other row is close to the exhaust gas inlet (10.1). The upper fresh air box (21.1) of the heat exchanger (21) is transversely divided into a first chamber (21.11) and a second chamber (21.12). The first chamber (21.11) is located on one side of the exhaust gas outlet (10.2) and is connected to the row of fresh air pipes (21.3) of the heat exchanger (21) close to the exhaust gas outlet (10.2). The second chamber (21.12) is located on one side of the exhaust gas inlet (10.1) and is connected to the other row of fresh air pipes (21.3) of the heat exchanger (21) close to the exhaust gas inlet (10.1).

5. The exhaust gas heat recovery system according to claim 4, characterized in that: The fresh air pipe (21.3) of the heat exchanger (21) close to the waste gas inlet (10.1) is divided into two rows, one row is close to the waste gas outlet (10.2), and the other row is close to the waste gas inlet (10.1). The upper fresh air box (21.1) of the heat exchanger (21) is transversely divided into a third chamber (21.13) and a fourth chamber (21.14). The third chamber (21.13) is located on one side of the waste gas outlet (10.2) and is connected to the row of fresh air pipes (21.3) of the heat exchanger (21) close to the waste gas outlet (10.2). The fourth chamber (21.14) is located on one side of the waste gas inlet (10.1) and is connected to the other row of fresh air pipes (21.3) of the heat exchanger (21) close to the waste gas inlet (10.1).

6. The exhaust gas heat recovery system according to claim 5, characterized in that: The first chamber (21.11) is connected to the upper fresh air box (21.1) closest to the exhaust gas outlet (10.2), the second chamber (21.12) is connected to the third chamber (21.3), and the fourth chamber (21.4) is connected to the upper fresh air box (21.1) closest to the exhaust gas inlet (10.1).

7. The exhaust gas heat recovery system according to claim 6, characterized in that: The lower fresh air box (21.2) of the heat exchanger (21) closest to the exhaust gas inlet (10.1) is provided with a cool fresh air inlet, and the lower fresh air box (21.2) of the heat exchanger (21) closest to the exhaust gas outlet (10.2) is provided with a hot fresh air outlet, so that the exhaust gas and the fresh air flow in opposite directions.

8. The exhaust gas heat recovery system according to any one of claims 1 to 7, characterized in that: All fresh air ducts (21.3) are oval flat tubes and have narrow arc surfaces as exhaust gas windward surfaces. An air gap is reserved between each of the new air ducts (21.3) for the exhaust gas to pass through.

9. The exhaust gas heat recovery system according to claim 1, characterized in that: The waste gas inlet (10.1) is connected to a secondary filter unit (30), the secondary filter unit (30) comprising a secondary filter box (31) fixedly connected to the heat insulation box (10) and communicating with the waste gas inlet (10.1), and an air distribution net (32) and a secondary manual filter net (33) are arranged inside the secondary filter box (31).

10. The exhaust gas heat recovery system according to claim 9, characterized in that: The secondary filter box (31) is connected to the primary filter part (40), the primary filter part (40) comprises a primary filter box (41) fixedly connected and communicating with the secondary filter box (31), a 28-mesh rotating filter screen disk (42) is arranged inside the primary filter box (41), the 28-mesh rotating filter screen disk (42) is connected to a motor (43) for driving the rotating filter screen disk (42), and a steam pipe for spraying steam toward the screen surface and a water spray pipe for spraying water toward the screen surface are arranged on the side of the 28-mesh rotating filter screen disk (42).

Images