Waste heat recovery device and industrial flue gas waste heat recovery system

Abstract

The utility model provides an industrial flue gas waste heat recovery system which comprises a flue gas heat exchange box body, a heat exchange assembly and an ash removal mechanism and further comprises an opening and closing mechanism arranged at the top of the flue gas heat exchange box body, and an inlet and an outlet are formed in the top of the flue gas heat exchange box body; the opening and closing mechanism comprises a moving frame, a sealing guide piece, a sealing cover plate and an opening and closing push rod, and the moving frame is configured to be driven by the opening and closing push rod to do linear reciprocating motion in the horizontal direction; the sealing cover plate is configured on the movable frame to vertically reciprocate and is provided with a matching piece; and the ash removal mechanism can enable a spray pipe to extend into the flue gas heat exchange box body through the inlet and outlet. The opening and closing operation of the inlet and outlet in the top of the flue gas heat exchange box can be achieved through the opening and closing mechanism, so that the spray pipe can stretch into the box during ash removal and is arranged outside the box when ash is not removed, direct contact between the spray pipe and flue gas is effectively avoided, and the ash removal effect of the spray pipe is ensured.

Description

Technical Field

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

[0002] Industrial flue gas is a high-temperature waste gas generated during industrial production. Since it carries a lot of heat, the recovery of flue gas waste heat can reduce production energy consumption. At present, the common practice is to use a heat exchange box with a heat exchange component to exchange heat between the flue gas and the heat transfer medium, so that the flue gas temperature drops and the heat transfer medium temperature rises. After the heat transfer medium is heated, it can act on other heat-using links.

[0003] In addition to carrying heat, flue gas also carries many harmful particles. During long-term operation, dust will accumulate on the outer wall of the heat exchange tube, which will affect the heat exchange efficiency over time. The patent with publication number CN217952346U discloses an industrial flue gas waste heat recovery heat exchanger, which uses compressed air as a power source to remove dust accumulation in the heat exchanger. However, this structure of the heat exchanger brings new problems, namely, the compressed air connecting branch pipe and the compressed air nozzle are installed inside the heat exchange box and are in a high-temperature flue gas environment for a long time. On the one hand, the nozzle may be blocked by dust accumulation. On the other hand, the compressed air connecting branch pipe itself cannot be self-cleaned. Over time, dirt will accumulate on its outer wall, especially the dirt near the nozzle will affect the direction of air outlet, thereby affecting the dust cleaning effect. In addition, since the impact force of compressed air decreases with increasing distance, it will cause inadequate cleaning at the far end. Summary of the invention

[0004] The object of the present invention is to provide a waste heat recovery device and an industrial flue gas waste heat recovery system, which can achieve the purpose of preventing the ash cleaner from being invaded by high-temperature flue gas in a non-cleaning situation.

[0005] To achieve the above object, the present invention provides the following technical solution: a waste heat recovery device, comprising a flue gas heat exchange box, a heat exchange component and a ash cleaning mechanism, and also comprising an opening and closing mechanism arranged on the top of the flue gas heat exchange box, wherein the top of the flue gas heat exchange box is provided with an inlet and outlet;

[0006] The opening and closing mechanism comprises a moving frame, a sealing guide, a sealing cover plate and an opening and closing push rod, wherein the moving frame is configured to be driven by the opening and closing push rod to linearly reciprocate in the horizontal direction; the sealing cover plate is configured on the moving frame to reciprocate vertically and has a matching piece;

[0007] When the moving frame is at the beginning of the stroke, the sealing cover plate is separated from the inlet and outlet and the two do not overlap each other;

[0008] When the moving frame is at the end of the stroke, the sealing cover plate is in sealing contact with the inlet and outlet and the two are completely overlapped;

[0009] During the movement of the movable frame from the starting end to the end of its stroke, the matching member can match with the sealing guide member and drive the sealing cover plate to move downward under the action of the matching member;

[0010] The cleaning mechanism can extend the nozzle into the flue gas heat exchange box through the inlet and outlet.

[0011] Furthermore, the opening and closing mechanism further includes a return spring, and the return spring is configured to drive the sealing cover plate to have a tendency to move upward relative to the movable frame.

[0012] Furthermore, the sealing guide is a plate body having an inclined guide surface and a horizontal guide surface; the inclined guide surface and the horizontal guide surface are smoothly transitionally connected, and during the movement of the movable frame from the beginning of its stroke to the end of its stroke, the mating piece successively forms contact and mating with the inclined guide surface and the horizontal guide surface.

[0013] Further, the mating piece is a mating roller, and the mating roller forms a rolling contact fit with the inclined guide surface and the horizontal guide surface circle.

[0014] Furthermore, a linear track is arranged on the top of the flue gas heat exchange box, and the movable frame moves linearly on the linear track through limiting rollers on both sides.

[0015] Furthermore, the cleaning mechanism includes a lifting push rod and a lifting frame, the lifting frame is configured to be driven by the lifting push rod to move linearly back and forth in the vertical direction, the ash cleaner is installed on the lifting frame, and the ash cleaner is a nozzle or an ultrasonic ash cleaner.

[0016] Furthermore, a mounting cavity which is recessed inwards and passes through the bottom is provided at the top center of the flue gas heat exchange box body, and the mounting cavity is not connected to the interior of the flue gas heat exchange box body; the lifting push rod is installed in the mounting cavity.

[0017] Furthermore, at least two of the heat exchange components, nozzles and opening and closing mechanisms are provided, and they are arranged one by one.

[0018] The present invention also provides an industrial flue gas waste heat recovery system, comprising a waste heat recovery device, wherein the waste heat recovery device is the above-mentioned waste heat recovery device.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1) The present invention adopts an opening and closing mechanism to realize the opening and closing operation of the inlet and outlet at the top of the flue gas heat exchange box, so that the nozzle can be extended into the box when cleaning and placed outside the box when not cleaning, effectively avoiding direct contact between the nozzle and the flue gas, thereby ensuring the cleaning effect of the nozzle.

[0021] 2) The opening and closing mechanism of the present invention uses a fit-in manner to achieve the sealing and opening of the inlet and outlet by the sealing cover plate, and the sealing guide is used to automatically limit the position after sealing, which greatly reduces the risk of failure.

[0022] 3) The nozzle in the present invention connects clean water and a dust-removing agent, and removes the accumulated dust by chemical reaction, and the removal efficiency is higher than that of compressed air dust removal.

[0023] 4) The sonic dust cleaner of the present invention can expand the scope of action and effectively remove the dust accumulated on the heat exchange tubes and the box wall. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a structural stereogram of the waste heat recovery device in the present invention under the dust removal condition (the arrow in the figure indicates the flow direction);

[0025] Figure 2 for Figure 1 A partial enlarged view of the middle A;

[0026] Figure 3 for Figure 1 The structural side view of the waste heat recovery device in the dust cleaning condition is shown;

[0027] Figure 4 for Figure 3 Structural cross-section view along the BB direction;

[0028] Figure 5 for Figure 4 A partial enlarged view of point C in the middle;

[0029] Figure 6 for Figure 1 The structural stereogram of the waste heat recovery device shown in the figure is in a non-cleaning condition;

[0030] Figure 7 for Figure 6 A partial enlarged view of point D in the middle;

[0031] Figure 8 for Figure 1 The structural side view of the waste heat recovery device in non-cleaning working condition is shown;

[0032] Fig. 9 for Figure 1 A structural stereogram of the opening and closing mechanism in the waste heat recovery device shown (the sealing guide and the opening and closing push rod are not shown);

[0033] Fig.10 for Figure 1 A structural cross-sectional view of another alternative example of a cleaning mechanism in a waste heat recovery device;

[0034] Fig.11This is a flow chart of the industrial flue gas waste heat recovery system in the present invention (solid arrows indicate the medium conveying direction, and hollow arrows indicate the flue gas conveying direction). DETAILED DESCRIPTION

[0035] The technical solutions in the embodiments of the present invention are described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0036] like Figures 1 to 10 As shown, this embodiment discloses a waste heat recovery device, including a flue gas heat exchange box 1, a heat exchange component 4, a ash cleaning mechanism and an opening and closing mechanism. Four heat exchange components 4 are provided, and the opening and closing mechanism is provided at the top of the flue gas heat exchange box 1. Two inlets and outlets 1.7 are provided at the top of the flue gas heat exchange box 1. The inlet and outlet 1.7 are located above the front and rear heat exchange components 4. The size of the inlet and outlet 1.7 needs to be determined according to the size of the ash cleaner. The larger the radial size of the ash cleaner, the larger the diameter of the inlet and outlet 1.7. A side wall of the flue gas heat exchange box 1 is provided with several groups of water channel joints, and each group of water channel joints is respectively connected to the two ends of each heat exchange component 4, and the outside thereof is connected in sequence through a connecting pipe 5 to form a complete water channel connected end to end. In this way, there will be two remaining water channel joints that are not connected to the connecting pipe 5, one of which is used as a water inlet and the other as a water outlet. The medium conveying direction is opposite to the flue gas conveying direction, so the residual heat of the flue gas after heat exchange and cooling will preheat the medium just input into the flue gas heat exchange box 1, which can improve the utilization rate of residual heat. It is known that the inside of the flue gas heat exchange box 1 and its container components are all treated with anti-corrosion, which is a conventional method and will not be described in detail.

[0037] The opening and closing mechanism includes a moving frame 7, a sealing guide 10, a sealing cover plate 15 and an opening and closing push rod 13. Two sets of linear rails 6 are fixedly installed on the top of the flue gas heat exchange box 1. The linear rails 6 are made of channel steel, and their notches are set inward. There are two moving frames 7. Limit rollers 18 are installed on both sides of the moving frame 7. The limit rollers 18 include an upper limit wheel and a lower limit wheel. The upper limit wheel contacts the upper groove wall of the linear rail 6, and the lower limit wheel contacts the lower groove wall. In this way, by utilizing the limiting matching relationship between the limit roller 18 and the corresponding linear rail 6, the moving frame 7 is restricted in the notch of the linear rail 6 and can only move in a straight line to ensure the sealing effect of the inlet and outlet 1.7.

[0038] The opening and closing push rod 13 is fixedly mounted on one end of the linear track 6, and the push rod is connected to the moving frame 7, thereby driving the moving frame 7 to make a horizontal linear reciprocating movement along the linear track 6. A plurality of guide pillars 9 are arranged on the top surface of the sealing cover plate 15, and a vertical sliding installation is formed between the guide pillars 9 and the moving frame 7, so that the sealing cover plate 15 can vertically reciprocate relative to the moving frame 7. A central T-shaped column 15.1 is arranged in the center of the top surface of the sealing cover plate 15, and matching pieces 16 are arranged at both ends of the central T-shaped column 15.1. The sealing guide 10 is fixedly mounted on the linear track 6, and its function is to cooperate with the matching piece 16, thereby driving the sealing cover plate 15 to move vertically. Combined with the moving process of the moving frame 7, the movement state of the sealing cover plate 15 is: when the opening and closing push rod 13 is in a fully retracted state, the moving frame 7 is at the beginning of the stroke, and the sealing cover plate 15 is separated from the inlet and outlet 1.7 and the two do not overlap each other. At this time, the inlet and outlet 1.7 are completely exposed and there is no obstruction above, and the nozzle can pass through the inlet and outlet 1.7 to enter the flue gas heat exchange box 1. When the opening and closing push rod 13 is in a fully extended state, the movable frame 7 is at the end of the stroke, and the sealing cover plate 15 is in sealing contact with the inlet and outlet 1.7 and the two are completely overlapped. At this time, the inlet and outlet 1.7 are completely blocked by the sealing cover plate 15, and the nozzle cannot pass through the inlet and outlet 1.7 to enter the flue gas heat exchange box 1. In the process of the push rod of the opening and closing push rod 13 extending outward, the movable frame 7 moves from the beginning of its stroke to the end of its stroke, and the matching piece 16 can cooperate with the sealing guide 10 and drive the sealing cover plate 15 to move downward under its action. Specifically, the sealing guide 10 is a metal plate body having an inclined guide surface and a horizontal guide surface. The inclined guide surface and the horizontal guide surface are connected in a smooth transition. The matching piece 16 is a matching roller, and the matching roller forms a rolling contact match with the inclined guide surface and the horizontal guide surface. When the mating roller contacts the inclined guide surface, the inclined guide surface generates a downward force on the mating roller, which causes the sealing cover plate 15 to move downward. When the mating roller slides over the inclined guide surface to the horizontal guide surface, the horizontal guide surface is at the lowest position, so the sealing cover plate 15 moves downward to the lowest position, and the sealing cover plate 15 contacts and overlaps the inlet and outlet 1.7. When the moving frame 7 moves to the end, the sealing cover plate 15 completely overlaps the inlet and outlet 1.7, so that the inlet and outlet 1.7 is completely blocked. It can be known that when the sealing cover plate 15 blocks the inlet and outlet 1.7, the horizontal guide surface will limit the mating roller, preventing the sealing cover plate 15 from moving upward, thereby ensuring the sealing effect.

[0039] like Figure 5As shown, preferably, the surface where the sealing cover plate 15 contacts the inlet and outlet 1.7 is provided with a high temperature resistant sealing gasket 19, such as a polytetrafluoroethylene gasket or a silicone gasket, which not only has good sealing performance, but also has high temperature resistance. It can be known that when the sealing cover plate 15 contacts the inlet and outlet 1.7, the high temperature resistant sealing gaskets on both are under pressure, and the deformation of the material is used to form a seal, and during the movement, the sealing form is a dynamic seal, and after being completely blocked, the sealing form becomes a static seal. The sealing principle is a technology, so it is not repeated.

[0040] When the opening and closing mechanism needs to be opened, the moving frame 7 moves from the end position to the starting position, and the matching roller rolls from the horizontal guide surface to the inclined guide surface. The matching roller is no longer under downward pressure, and the sealing cover plate 15 needs to move upward. The power for the upward movement of the sealing cover plate 15 comes from the return spring 8 installed on the guide rod 9. One end of the return spring 8 abuts against the top boss of the guide rod 9, and the other end abuts against the moving frame 7. After being compressed, the return spring 8 provides the guide rod 9 with a force to move upward.

[0041] As a preferred example, the dust cleaning mechanism includes a lifting push rod 2 and a lifting frame 3, and the lifting frame 3 is configured to be driven by the lifting push rod 2 to move back and forth in a straight line in the vertical direction. The lifting push rod 2 is installed outside the flue gas heat exchange box 1, and can be installed on one side of the flue gas heat exchange box 1, or installed in the installation cavity at the top center of the flue gas heat exchange box 1. The installation cavity is formed by the top center of the flue gas heat exchange box 1 being recessed inward and penetrating its bottom. It is not connected to the inside of the flue gas heat exchange box 1, so it belongs to the space outside the box. The lifting push rod 2 is set upward, and its push rod is connected to the lifting frame 3.

[0042] Two dust collectors 11 are installed on the lifting frame 3, and the dust collectors 11 are nozzles or sonic dust collectors. In a preferred example, the dust collector 11 is a nozzle, and a plurality of pressure nozzles 12 facing different directions and at different heights are distributed on the nozzle. The nozzle is connected to the cleaning source through a water pipe 17. The cleaning source is a cleaning water tank and a dust removal agent tank, and the aforementioned cleaning medium is supplied by a water pump. The dust removal process can be to first spray a chemical agent to react with the dirt, and then spray cleaning water to peel it off the surface of the object. The effect of using chemical agents to remove dirt is better because the agent reacts with the dirt to generate other substances, which will reduce the adhesion of the surface of the object, so that it can be easily washed away by water. The specific agent type is determined according to the flue gas, which will not be repeated here. However, the use of compressed gas has the problem of limited range of action, resulting in a small impact pressure at some locations and cannot be effectively removed. Although dust can also be cleaned, the overall effect is not as good as the combination of agents and cleaning.

[0043] As an alternative, the ash cleaner 11 can also be an acoustic ash cleaner. The number and installation angle of the acoustic ash cleaner can be set according to actual needs, which will not be elaborated here. The acoustic ash cleaner is connected to the air source, and converts the kinetic energy of the pressure gas (compressed air, nitrogen, etc.) provided by the air source into the wave energy of sound waves or infrasound waves. The wave energy of sound waves or infrasound waves is used to displace various deposits and leave their original positions, thereby achieving the purpose of removing dust and unblocking. Compared with the method of using compressed air to directly act on the dust in the prior art, the acoustic ash cleaner has an adjustable installation angle, a wider range of action, and effectively avoids dead corners. It should be noted that the length of the acoustic ash cleaner is shorter than the nozzle. Therefore, when working, the acoustic ash cleaner can be driven to rise and fall within a certain range by controlling the lifting push rod 2, so as to achieve cleaning at different heights.

[0044] It can be known that multiple inlets and outlets 1.7 can be provided in the width direction, so as to improve the coverage of the cleaning medium. Correspondingly, the same number of opening and closing mechanisms are also provided. However, all the moving racks 7 in the moving direction of the moving rack 7 can be driven by the same opening and closing push rod 13 to realize the opening and closing control of all the sealing cover plates 15 in this direction. A nozzle is also provided corresponding to each inlet and outlet 1.7.

[0045] In order to discharge dirt, a funnel-shaped sewage outlet 1.5 is provided at the bottom of the smoke collection box 1. The funnel-shaped sewage outlet 1.5 is equipped with a valve 14. Under normal conditions of collecting waste heat, the valve 14 is closed, and under sewage discharge conditions, the valve 14 is opened. The opening and closing push rod 13 and the lifting push rod 2 are both hydraulic cylinders or electric cylinders, which is a prior art and will not be described in detail.

[0046] When dust cleaning is not required, the opening and closing mechanism is in a closed state, the inlet and outlet 1.7 are blocked, the lifting push rod 2 is in a fully extended state, and the nozzle is located above the smoke collection box 1. When dust cleaning is required, the smoke delivery is stopped, and then the opening and closing mechanism is controlled to be in an open state, and the sealing cover plate 15 leaves the inlet and outlet 1.7 to make it completely exposed. At this time, the lifting push rod 2 retracts, driving the nozzle to extend into the inside of the smoke collection box 1, and then the air source or water source is connected to spray the dust cleaning medium into the inside of the smoke collection box 1. After the dust cleaning is completed, the valve 14 is opened to discharge the dirt from the sewage outlet 1.5, and then the valve 14 is closed, the nozzle is withdrawn, and the opening and closing mechanism is controlled to be in a closed state again, and finally the smoke is delivered for preheating recovery.

[0047] The present invention also provides an industrial flue gas waste heat recovery system, comprising the above waste heat recovery device, the entire flue gas waste heat recovery process is as follows Fig. 9As shown, the air inlet 1.2 of the flue gas collection box 1 is connected to the exhaust outlet of the production line, and the air outlet 1.1 is connected to the flue gas treatment device, such as desulfurization equipment, denitrification equipment, dust removal equipment, etc., which needs to be specifically configured according to the type of flue gas. The flue gas is discharged into the atmosphere through the chimney after purification. The heat exchange component 4 of the waste heat recovery device is connected to the water tank, and the water is heated after heat exchange. The outlet water can enter the heat storage body to further heat and generate steam for use in related processes of the production line.

[0048] It should be noted that the control part in the present invention is prior art, so it will not be described in detail.

[0049] The matters not described in detail in the present invention are all known technologies to those skilled in the art.

[0050] In the description of the present invention, it should be understood that the terms "upper", "lower", "left", "right", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, and a specific direction structure and operation, and therefore, cannot be understood as a limitation of the present invention. In addition, "first" and "second" are only for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features.

[0051] In the description of the present invention, unless otherwise specified, "plurality" means two or more than two. In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal connection of two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0052] Finally, it should be noted that the above specific implementation methods are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified and replaced by equivalents without departing from the spirit and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A waste heat recovery device, comprising a flue gas heat exchange box (1), a heat exchange component (4) and a dust cleaning mechanism, characterized in that: It also includes an opening and closing mechanism arranged on the top of the flue gas heat exchange box (1), and the top of the flue gas heat exchange box (1) is provided with an inlet and outlet (1.7); The opening and closing mechanism comprises a movable frame (7), a sealing guide (10), a sealing cover plate (15) and an opening and closing push rod (13); the movable frame (7) is configured to be driven by the opening and closing push rod (13) to move linearly back and forth in a horizontal direction; the sealing cover plate (15) is configured on the movable frame (7) to move vertically back and forth, and has a matching member (16); When the movable frame (7) is at the beginning of its travel, the sealing cover plate (15) is separated from the inlet and outlet (1.7) and the two do not overlap each other; When the movable frame (7) is at the end of its travel, the sealing cover plate (15) is in sealing contact with the inlet and outlet (1.7) and the two completely overlap; During the movement of the movable frame (7) from the start end of its stroke to the end end of its stroke, the matching member (16) can match with the sealing guide member (10) and drive the sealing cover plate (15) to move downward under its action; The ash cleaning mechanism is capable of extending the ash cleaner (11) into the flue gas heat exchange box (1) through the inlet and outlet (1.7).

2. A waste heat recovery device according to claim 1, characterized in that: The opening and closing mechanism further comprises a return spring (8), wherein the return spring (8) is configured to drive the sealing cover plate (15) to have a tendency to move upward relative to the movable frame (7).

3. A waste heat recovery device according to claim 1, characterized in that: The sealing guide (10) is a plate body having an inclined guide surface and a horizontal guide surface; the inclined guide surface and the horizontal guide surface are smoothly transitionally connected, and when the movable frame (7) moves from the beginning of its stroke to the end of its stroke, the matching piece (16) successively forms contact matching with the inclined guide surface and the horizontal guide surface.

4. A waste heat recovery device according to claim 3, characterized in that: The matching piece (16) is a matching roller, and the matching roller forms a rolling contact match with the inclined guide surface and the horizontal guide surface circle.

5. The waste heat recovery device according to claim 1, characterized in that: A linear track (6) is provided on the top of the flue gas heat exchange box (1), and the movable frame (7) moves linearly on the linear track (6) via limiting rollers (18) on both sides.

6. A waste heat recovery device according to claim 1, characterized in that: The dust cleaning mechanism comprises a lifting push rod (2) and a lifting frame (3); the lifting frame (3) is configured to be driven by the lifting push rod (2) to move linearly back and forth in a vertical direction; the dust cleaner (11) is mounted on the lifting frame (3); the dust cleaner (11) is a nozzle or a sonic dust cleaner.

7. A waste heat recovery device according to claim 6, characterized in that: The center of the top of the flue gas heat exchange box (1) is provided with an installation cavity which is recessed inwards and passes through the bottom thereof, and the installation cavity is not connected to the interior of the flue gas heat exchange box (1); the lifting push rod (2) is installed in the installation cavity.

8. A waste heat recovery device according to any one of claims 1 to 7, characterized in that: At least two of the heat exchange components (4), dust collectors (11) and opening and closing mechanisms are provided, and are arranged one by one in a matching manner.

9. An industrial flue gas waste heat recovery system, comprising a waste heat recovery device, characterized in that: The waste heat recovery device is a waste heat recovery device as described in claim 1.

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