Low-speed diesel engine tail gas treatment device and method

Abstract

The invention relates to the technical field of diesel engine tail gas treatment, and provides a low-speed diesel engine tail gas treatment device and method.The low-speed diesel engine tail gas treatment device comprises a treatment box, the interior of the treatment box is divided into a heat recovery cavity and a gas collecting cavity, and a plurality of heat exchange pipes are distributed in the heat recovery cavity; gas guide hoppers in one-to-one correspondence with the heat exchange pipes are arranged on the side, close to the treatment box, of the flow dividing piece; a sweeping mechanism is arranged between each air guide hopper and the corresponding heat exchange pipe, each sweeping mechanism comprises a support arranged in the corresponding air guide hopper and a rod piece rotationally arranged on the support, and a propeller and a strip brush are arranged on each rod piece; the airflow impacts the propeller to drive the rod piece to rotate, so that the strip brush is attached to the inner wall of the heat exchange pipe to revolve, the inner wall of the heat exchange pipe is continuously cleaned in the tail gas heat exchange process, particulate matter in tail gas is prevented from being attached to the inner wall of the heat exchange pipe, the heat exchange pipe keeps efficient heat exchange, and the heat exchange effect is guaranteed.

Description

Technical Field

[0001] The invention relates to the technical field of diesel engine exhaust treatment, in particular to a low-speed diesel engine exhaust treatment device and method. Background Art

[0002] In the shipbuilding industry, low-speed diesel engines are the main power source, and their emissions are directly related to environmental protection. As ship emission standards continue to tighten, how to effectively treat low-speed diesel engine exhaust and reduce harmful emissions has become an important challenge facing the shipbuilding industry.

[0003] Heat recovery is an indispensable part of the exhaust treatment process of low-speed diesel engines. At present, although the exhaust gas is filtered before entering the heat exchange mechanism to remove particulate matter, due to the limitations of current filtering technology, there will still be a certain amount of fine particulate matter in the exhaust gas. These particles will inevitably contact the inner wall of the heat exchange tube during the flow of exhaust gas and gradually adhere to the tube wall. As time goes by, more and more particulate matter accumulates on the inner wall of the heat exchange tube, resulting in a reduction in heat exchange area and a significant decrease in heat exchange efficiency, which affects the effect of heat recovery. In addition, it is extremely inconvenient to clean the particles adhered to the inner wall of the heat exchange tube. The traditional cleaning method is usually to disassemble the heat exchange tube first, and then use a high-pressure water gun or chemical cleaning agent to clean it, which is time-consuming and labor-intensive.

[0004] Therefore, the present invention proposes a low-speed diesel engine exhaust treatment device and method to solve the above problems. Summary of the invention

[0005] The embodiment of the present invention aims to provide a low-speed diesel engine exhaust treatment device and method to solve the above-mentioned problems.

[0006] To achieve the above object, the present invention provides the following technical solutions:

[0007] A low-speed diesel engine exhaust treatment device, comprising a treatment box, wherein the interior of the treatment box is divided into a heat recovery chamber and an air collection chamber, wherein a plurality of heat exchange tubes are evenly arranged in the heat recovery chamber, and one end of the heat exchange tube is connected to the air collection chamber, and the other end is located outside the heat recovery chamber, wherein the treatment device further comprises a flow divider, wherein a side of the flow divider close to the treatment box is provided with an air guide scoop corresponding to the heat exchange tubes one by one, wherein one end of the air guide scoop away from the flow divider is butted against one end of the corresponding heat exchange tube located outside the heat recovery chamber, and the flow divider can be moved away from the treatment box along the direction of the extension line of the heat exchange tube;

[0008] A cleaning mechanism is provided between each of the air guide scoops and the corresponding heat exchange tube for real-time cleaning of the inner wall of the heat exchange tube when recovering exhaust gas heat energy. The cleaning mechanism includes a bracket arranged in the air guide scoop and a rod rotatably arranged on the bracket. The rod is provided with a propeller and a strip brush in contact with the inner wall of the heat exchange tube.

[0009] In an optional solution: a sealing ring is provided at one end of each heat exchange tube located outside the heat recovery chamber.

[0010] In an optional solution, the rod member extends into the heat exchange tube, and a slow-flow cone for slowing down the exhaust gas flow rate is evenly provided on the rod section of the rod member located in the heat exchange tube.

[0011] In an optional solution, the narrow end of the slow-flow cone is opposite to the flow direction of the exhaust gas in the heat exchange tube.

[0012] In an optional scheme: the bracket is provided with a through hole for the rod to pass through, and the rod is coaxial with the through hole, the bracket is evenly provided with a plurality of protrusions around the circumference of the through hole, the rod is passed through a fixed U-shaped part, rollers are provided at both ends of the U-shaped part, the bracket is provided with a rotatable annular part coaxial with the through hole, the annular part is provided with a plurality of vertical poles passing through the U-shaped part, each of the vertical poles is provided with a limiting cap at one end away from the annular part, and a compression spring is sleeved on the rod section of each vertical pole located between the U-shaped part and the limiting cap.

[0013] In an optional solution: the diameter of the through hole is larger than the diameter of the rod, and a plurality of balls that contact and abut against the rod are evenly embedded on the wall of the through hole circumferentially.

[0014] In an optional solution: the processing device also includes a separation mechanism for realizing the movement of the diverter along the extension line of the heat exchange tube toward the processing box, the separation mechanism includes a slide rail and a slide seat slidably arranged on the slide rail, the slide seat is fixedly connected to the diverter, and the slide rail is provided with a rotatable threaded rod and a driving member for driving the threaded rod to rotate, and the threaded rod threadably cooperates with and passes through the slide seat.

[0015] A method for treating exhaust gas from a low-speed diesel engine, using the exhaust gas treatment device for a low-speed diesel engine described in any one of the above technical solutions, comprising the following steps:

[0016] S1: Cold water is continuously introduced into the heat recovery chamber. After the exhaust gas enters the diverter, it enters the corresponding heat exchange tube through each air guide. The heat in the exhaust gas is transferred to the cold water through the heat exchange tube to achieve heat exchange. The hot water generated after the heat exchange is discharged. The airflow impacts the propeller to drive the rod to rotate, so that the strip brush revolves to continuously clean the inner wall of the heat exchange tube;

[0017] S2: The exhaust gas after heat exchange is collected in the gas collection cavity and discharged.

[0018] Compared with the prior art, the beneficial effects of the embodiments of the present invention are as follows:

[0019] After the exhaust gas enters the diverter, it enters the corresponding heat exchange tube through each air guide hopper. The airflow impacts the propeller, thereby driving the rod to rotate, causing the strip brush to revolve along the inner wall of the heat exchange tube, thereby continuously cleaning the inner wall of the heat exchange tube during the exhaust gas heat exchange process, preventing particulate matter in the exhaust gas from adhering to the inner wall of the heat exchange tube, allowing the heat exchange tube to maintain high-efficiency heat exchange and ensure the heat exchange effect. The diverter is periodically moved along the extension line of the heat exchange tube toward the treatment box to bring out all the strip brushes, and the strip brushes are cleaned outside the treatment box. There is sufficient space and the operation is convenient.

[0020] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The drawings herein are incorporated into and constitute a part of the specification to illustrate embodiments consistent with the present application and are used together with the specification to explain the principles of the present application. At the same time, these drawings and text descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application for those skilled in the art by referring to specific embodiments.

[0022] Figure 1 It is a schematic diagram of the structure of the present invention.

[0023] Figure 2 It is a schematic diagram (part) of the arrangement between the air guide hopper, the rod and the strip brush in the present invention.

[0024] Figure 3 It is a structural schematic diagram of the processing box in the present invention.

[0025] Figure 4 It is a schematic diagram of the arrangement between the air guide scoop and the bracket in the present invention.

[0026] Figure 5 It is a schematic diagram of the arrangement among the rod, the strip brush and a plurality of slow flow cones in the present invention.

[0027] Figure 6 It is a schematic diagram of the arrangement between the rod, the bracket and the U-shaped member in the present invention.

[0028] Figure 7 This is a schematic diagram of another angle setting between the rod, the bracket and the U-shaped member in the present invention.

[0029] Notes on figure numbers: 1-processing box, 101-heat recovery chamber, 102-air collecting chamber, 2-heat exchange tube, 3-rod, 4-slow flow cone, 5-air guide hopper, 6-diverter, 7-slide rail, 8-threaded rod, 9-driving member, 10-slide seat, 11-sealing ring, 12-propeller, 13-brush, 14-bracket, 15-bump, 16-ring, 17-vertical pole, 18-U-shaped member, 19-limiting cap, 20-compression spring, 21-roller, 22-through hole, 23-ball. DETAILED DESCRIPTION

[0030] The present application is further described in detail below in conjunction with the accompanying drawings. It is necessary to point out here that the following specific implementation methods are only used to further illustrate the present application and cannot be understood as limiting the scope of protection of the present application. Technical personnel in this field can make some non-essential improvements and adjustments to the present application based on the above application content.

[0031] See also Figure 1 to Figure 4 A low-speed diesel engine exhaust treatment device, comprising a treatment box 1, wherein the interior of the treatment box 1 is divided into a heat recovery chamber 101 and an air collection chamber 102, wherein a plurality of heat exchange tubes 2 are evenly arranged in the heat recovery chamber 101, and one end of the heat exchange tube 2 is connected to the air collection chamber 102, and the other end is located outside the heat recovery chamber 101, wherein the treatment device further comprises a flow divider 6, wherein a gas guide scoop 5 corresponding to the heat exchange tube 2 is arranged on one side of the flow divider 6 close to the treatment box 1, wherein one end of the gas guide scoop 5 away from the flow divider 6 is butted against one end of the corresponding heat exchange tube 2 located outside the heat recovery chamber 101, and the flow divider 6 can move away from the treatment box 1 along the direction of the extension line of the heat exchange tube 2;

[0032] A cleaning mechanism is provided between each of the air guide scoops 5 and the corresponding heat exchange tube 2 for real-time cleaning of the inner wall of the heat exchange tube 2 when recovering the exhaust heat energy. The cleaning mechanism includes a bracket 14 provided in the air guide scoop 5 and a rod 3 rotatably provided on the bracket 14. The rod 3 is provided with a propeller 12 and a strip brush 13 in contact with the inner wall of the heat exchange tube 2.

[0033] It should be noted that the diverter 6 is provided with an exhaust gas inlet, the gas collecting chamber 102 is provided with an exhaust gas outlet, and the heat recovery chamber 101 is provided with a cold water inlet and a hot water outlet for discharging hot water after heat exchange.

[0034] When treating the exhaust gas of a low-speed diesel engine, cold water is continuously introduced into the heat recovery chamber 101. After the exhaust gas enters the diverter 6, it enters the corresponding heat exchange tube 2 through each air guide hopper 5. The heat in the exhaust gas is transferred to the cold water through the heat exchange tube 2 to achieve heat exchange. The hot water generated after the heat exchange is discharged, and the air flow impacts the propeller 12, thereby driving the rod 3 to rotate, so that the strip brush 13 revolves around the inner wall of the heat exchange tube 2, so that the inner wall of the heat exchange tube 2 is continuously cleaned during the exhaust gas heat exchange process, and the particulate matter in the exhaust gas is prevented from adhering to the inner wall of the heat exchange tube 2, so that the heat exchange tube 2 maintains high-efficiency heat exchange and ensures the heat exchange effect. The exhaust gas after heat exchange is collected in the gas collection chamber 102 and discharged into the subsequent treatment link (desulfurization, denitrification, etc., which are existing technologies and will not be described here) to complete the treatment. The diverter 6 is regularly moved along the extension line of the heat exchange tube 2 toward the treatment box 1 to bring out all the strip brushes 13, and the strip brushes 13 are cleaned outside the treatment box 1, so there is sufficient space and the operation is convenient.

[0035] Furthermore, a sealing ring 11 is provided at one end of each heat exchange tube 2 outside the heat recovery chamber 101 to ensure sealing when the end of the air guide scoop 5 is butted against the end of the corresponding heat exchange tube 2 to avoid exhaust gas leakage.

[0036] See also Figure 5 In one embodiment of the present invention, the rod 3 extends into the heat exchange tube 2, and a slow-flow cone 4 for slowing down the exhaust gas flow rate is evenly provided on the rod section of the rod 3 located in the heat exchange tube 2.

[0037] In this embodiment, a slow-flow cone 4 is provided to block and slow the flow of the exhaust gas, thereby slowing down the flow velocity of the exhaust gas in the heat exchange tube 2, thereby lengthening the time for the exhaust gas to pass through the heat exchange tube 2, ensuring sufficient heat exchange time and improving the heat exchange rate.

[0038] Furthermore, in this embodiment, the narrow end of the slow flow cone 4 is opposite to the flow direction of the exhaust gas in the heat exchange tube 2. The conical surface of the slow flow cone 4 can make the exhaust gas flow toward the inner wall of the heat exchange tube 2, thereby getting close to the inner wall of the heat exchange tube 2 to improve the heat exchange effect.

[0039] Please refer to the figure Figure 6 and Figure 7In one embodiment of the present invention, the bracket 14 is provided with a through hole 22 for the rod 3 to pass through, and the rod 3 is coaxial with the through hole 22. The bracket 14 is evenly provided with a plurality of protrusions 15 around the through hole 22. A fixed U-shaped member 18 is passed through the rod 3, and rollers 21 are provided at both ends of the U-shaped member 18. The bracket 14 is provided with a rotatable annular member 16 coaxial with the through hole 22. The annular member 16 is provided with a plurality of vertical rods 17 passing through the U-shaped member 18, and each of the vertical rods 17 is provided with a limiting cap 19 at one end away from the annular member 16, and a compression spring 20 is sleeved on the rod section of each vertical rod 17 located between the U-shaped member 18 and the limiting cap 19.

[0040] In this embodiment, when the rod 3 rotates, it drives the U-shaped member 18 to rotate synchronously. The rotation of the U-shaped member 18 drives the two rollers 21 to revolve, thereby cyclically contacting multiple protrusions 15. When the rollers 21 contact the protrusions 15, the rod 3 as a whole will be driven to move toward the diverter 6. When the rollers 21 no longer contact the protrusions 15, the rod 3 as a whole will be reset under the action of the compression spring 20. This cycle keeps the strip brush 13 in a vibrating state, which can effectively shake off the particles adhered to the strip brush 13, so that the strip brush 13 can be kept as clean as possible, reducing the frequency of cleaning the strip brush 13.

[0041] Furthermore, in this embodiment, the diameter of the through hole 22 is larger than the diameter of the rod 3, and a plurality of balls 23 that are in contact with and abut against the rod 3 are evenly embedded on the wall of the through hole 22 in a circumferential direction. By providing the balls 23, the rod 3 is contact-limited, and the sliding friction is converted into rolling friction, so that the rod 3 can rotate and reciprocate more smoothly.

[0042] See also Figure 1 In one embodiment of the present invention, the processing device also includes a separation mechanism for realizing the movement of the diverter 6 along the extension line of the heat exchange tube 2 toward the processing box 1. The separation mechanism includes a slide rail 7 and a slide seat 10 slidably arranged on the slide rail 7. The slide seat 10 is fixedly connected to the diverter 6. The slide rail 7 is provided with a rotatable threaded rod 8 and a driving member 9 for driving the threaded rod 8 to rotate (the driving member 9 is a rotating device such as a motor and a reduction motor in the prior art, which will not be described in detail here). The threaded rod 8 is threadedly matched to pass through the slide seat 10.

[0043] In this embodiment, the driving member 9 drives the threaded rod 8 to rotate so as to drive the slide seat 10 to slide, that is, to drive the diverter 6 to move away from the processing box 1 along the extension line of the heat exchange tube 2 and to reset.

[0044] The present invention also provides a method for treating exhaust gas from a low-speed diesel engine, which uses an exhaust gas treatment device for a low-speed diesel engine according to any one of the above technical solutions, comprising the following steps:

[0045] S1: cold water is continuously introduced into the heat recovery chamber 101, and the tail gas enters the diverter 6 and then enters the corresponding heat exchange tube 2 through each air guide 5. The heat in the tail gas is transferred to the cold water through the heat exchange tube 2 to achieve heat exchange. The hot water generated after the heat exchange is discharged, and the airflow impacts the propeller 12 to drive the rod 3 to rotate, so that the strip brush 13 revolves to continuously clean the inner wall of the heat exchange tube 2;

[0046] S2: The exhaust gas after heat exchange is collected in the gas collecting cavity 102 and discharged.

[0047] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A low-speed diesel engine exhaust treatment device, comprising a treatment box (1), characterized in that: The interior of the treatment box (1) is divided into a heat recovery chamber (101) and an air collection chamber (102); a plurality of heat exchange tubes (2) are evenly arranged in the heat recovery chamber (101); one end of the heat exchange tube (2) is connected to the air collection chamber (102), and the other end is located outside the heat recovery chamber (101); the treatment device further comprises a flow divider (6); a side of the flow divider (6) close to the treatment box (1) is provided with an air guide hopper (5) corresponding to each of the heat exchange tubes (2); an end of the air guide hopper (5) away from the flow divider (6) is butted against an end of the corresponding heat exchange tube (2) located outside the heat recovery chamber (101); the flow divider (6) can move along the direction of the extension line of the heat exchange tube (2) towards the treatment box (1); A cleaning mechanism is provided between each of the air guide scoops (5) and the corresponding heat exchange tube (2) for real-time cleaning of the inner wall of the heat exchange tube (2) when recovering exhaust gas heat energy. The cleaning mechanism comprises a bracket (14) provided in the air guide scoop (5) and a rod (3) rotatably provided on the bracket (14). The rod (3) is provided with a propeller (12) and a strip brush (13) in contact with the inner wall of the heat exchange tube (2).

2. The low-speed diesel engine exhaust treatment device according to claim 1, characterized in that: A sealing ring (11) is provided at one end of each heat exchange tube (2) located outside the heat recovery chamber (101).

3. The low-speed diesel engine exhaust treatment device according to claim 1, characterized in that: The rod (3) extends into the heat exchange tube (2), and a slow-flow cone (4) for slowing down the exhaust gas flow velocity is evenly arranged on the rod section of the rod (3) located in the heat exchange tube (2).

4. The low-speed diesel engine exhaust treatment device according to claim 3, characterized in that: The narrow end of the slow-flow cone (4) is opposite to the flow direction of the exhaust gas in the heat exchange tube (2).

5. The low-speed diesel engine exhaust treatment device according to claim 1, characterized in that: The bracket (14) is provided with a through hole (22) for the rod (3) to pass through, and the rod (3) and the through hole (22) are kept coaxially. The bracket (14) is provided with a plurality of protrusions (15) uniformly arranged around the through hole (22). A fixed U-shaped member (18) is passed through the rod (3), and rollers (21) are arranged at both ends of the U-shaped member (18). The bracket (14) is provided with a rotatable annular member (16) coaxial with the through hole (22). The annular member (16) is provided with a plurality of vertical rods (17) passing through the U-shaped member (18), and a limiting cap (19) is arranged at one end of each vertical rod (17) away from the annular member (16), and a compression spring (20) is sleeved on the rod section of each vertical rod (17) located between the U-shaped member (18) and the limiting cap (19).

6. The low-speed diesel engine exhaust treatment device according to claim 5, characterized in that: The diameter of the through hole (22) is larger than the diameter of the rod (3), and a plurality of rolling balls (23) that are in contact with and abut against the rod (3) are evenly embedded on the wall of the through hole (22) in a circumferential direction.

7. The low-speed diesel engine exhaust treatment device according to claim 1, characterized in that: The processing device also includes a separation mechanism for enabling the flow dividing member (6) to move along the extension line of the heat exchange tube (2) toward the processing box (1), the separation mechanism including a slide rail (7) and a slide seat (10) slidably arranged on the slide rail (7), the slide seat (10) being fixedly connected to the flow dividing member (6), the slide rail (7) being provided with a rotatable threaded rod (8) and a driving member (9) for driving the threaded rod (8) to rotate, the threaded rod (8) being threadedly fitted and passing through the slide seat (10).

8. A method for treating exhaust gas from a low-speed diesel engine, using the exhaust gas treatment device for a low-speed diesel engine as claimed in any one of claims 1 to 7, characterized in that: The following steps are involved: S1: cold water is continuously introduced into the heat recovery chamber (101), and the tail gas enters the diverter (6) and then enters the corresponding heat exchange tube (2) through each air guide hopper (5). The heat in the tail gas is transferred to the cold water through the heat exchange tube (2) to achieve heat exchange. The hot water generated after the heat exchange is discharged, and the air flow impacts the propeller (12), thereby driving the rod (3) to rotate, so that the strip brush (13) revolves to continuously clean the inner wall of the heat exchange tube (2); S2: The exhaust gas after heat exchange is collected in the gas collecting chamber (102) and discharged.

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