A flue gas heat exchanger and system for nonferrous smelting industry

Abstract

The present invention provides a flue gas heat exchanger and system for nonferrous smelting industry. The heat exchanger comprises a shell, and the heat exchanger shell comprises an upper box, a middle box, and an ash hopper. The middle box is disassembled to set a heat dissipation pipe, and a dust cleaning mechanism is arranged in the upper box, and an ash hopper is arranged below the heat dissipation pipe. A partition plate is arranged in the heat exchanger, and the partition plate separates the upper box into upper box I and upper box II, and separates the middle box into middle box I and middle box II. One of the upper box I and upper box II is connected to the flue gas inlet, and the other is connected to the flue gas outlet. The middle box I and the middle box II are connected through the ash hopper. The high-temperature flue gas goes through the shell process, and the high-temperature flue gas forms dust accumulation on the outer wall of the heat dissipation pipe, so that the dust cleaning chain can clean the dust accumulation on the outer wall of the heat dissipation pipe, and the cleaned dust accumulation falls into the ash hopper below the heat dissipation pipe, and the ash hopper can collect the dust accumulation conveniently. The flue gas cooling equipment is aimed at the flue gas temperature, strong corrosion, and high smoke dust concentration in the nonferrous smelting industry under harsh working conditions.

Description

Technical Field

[0001] The invention relates to high-temperature flue gas cooling and heat recovery equipment in the smelting industry, and in particular to a flue gas heat exchanger and a system thereof for the non-ferrous smelting industry. Background Art

[0002] At present, with the strengthening of the country's environmental protection governance, there are also higher requirements for flue gas emissions in the smelting industry. This also brings more challenges to users in the smelting industry. On the premise of ensuring production capacity, environmental emissions must be ensured. In today's world where every inch of land is valuable, products are optimized and three-dimensional space is used rationally. However, for the smelting industry, environmental emissions are the most important part of production. This environmental protection facility consists of a series of equipment. Because the flue gas has high temperature, high dust content, and corrosive characteristics, the flue gas must undergo cooling, primary dust removal (within 50mg / m³ at the outlet), desulfurization, denitrification, secondary dust removal (within 5mg / m³ at the outlet), and de-whitening. The flue gas temperature discharged from the smelting furnace is generally ≥550℃, so it cannot enter the dust collector directly. Because the maximum temperature that the high-temperature bag of the dust collector can withstand is also within 300℃, cooling facilities must be used for this purpose.

[0003] At present, the vast majority of flue gas heat exchangers in the nonferrous smelting industry mainly use shell-and-tube surface coolers and a small number of plate heat exchangers.

[0004] Shell and tube surface coolers, such as Fig.10 , 101 is the tube, 102 is the platform, 10 is the ash hopper. Its disadvantages are that it occupies a large space and relies on environmental self-heating to dissipate heat. With the changes in temperature during the four seasons and day and night, the outlet temperature varies widely and cannot be controlled. In addition, the equipment is usually made of carbon steel or boiler steel, which has a short service life. The advantages are that the equipment has low manufacturing cost, no use cost, and simple structure.

[0005] The structure of the plate heat exchanger is composed of a heat dissipation box, a fan, an ash hopper, etc., and a small number of equipment have added a dust cleaning mechanism. This type of heat exchanger is much more optimized than the traditional surface cooler. The advantages are: it can actively dissipate heat, collect a small amount of smoke in the flue gas, and reduce the floor space; there are also many disadvantages, such as: the plate structure cannot be disassembled, resulting in the service life of the equipment being determined by the heat sink, and the stamping parts that support the heat sink are prone to wear and cannot be repaired. It is because these cannot be installed with a dust cleaning mechanism that dust cleaning cannot be done. Over time, the gap between the plates is blocked and cannot play a role in heat dissipation. Therefore, it is rarely used.

[0006] In short, the flue gas heat exchange equipment in the current smelting industry market is ultimately lacking in technology. There is no relatively complete product that can meet the flue gas heat exchange needs of non-ferrous smelting. For this reason, our team has continued to research for several years, and combined with our group's own advantages, we have finally developed our new combined smelting flue gas heat exchanger. Summary of the invention

[0007] To solve the above problems, the present invention provides a flue gas heat exchanger and system for non-ferrous smelting industry, which is mainly aimed at flue gas cooling equipment under harsh working conditions such as high flue gas temperature, strong corrosiveness and high smoke dust concentration in non-ferrous smelting industry.

[0008] The technical solution of the present invention is: a flue gas heat exchanger for non-ferrous smelting industry, characterized in that: the heat exchanger includes a shell, a flue gas outlet and a flue gas inlet; the heat exchanger shell includes an upper box body, a middle box body and an ash hopper from top to bottom, the middle box body is a heat dissipation box body, at least two heat dissipation pipes arranged in parallel are detachably arranged inside the middle box body, a fan is arranged on the side of the middle box body, the cold air blown in by the fan is connected to the air inlet, the air inlet is connected to one end of the heat dissipation pipe, and the other end of the heat dissipation pipe is connected to the air outlet, a dust cleaning mechanism is arranged in the upper box body, and an ash hopper is arranged below the heat dissipation pipe; a partition plate is arranged in the heat exchanger, the partition plate separates the upper box body into upper box body I and upper box body II, the partition plate separates the middle box body into middle box body I and middle box body II, one of the upper box body I and upper box body II is connected to the flue gas inlet, and the other is connected to the flue gas outlet, and the middle box body I and the middle box body II are connected through the ash hopper.

[0009] The heat dissipation pipe is a flat pipe.

[0010] The heat dissipation pipes are arranged in a matrix in the middle box body I and the middle box body II, respectively. Flower plates for fixing the heat dissipation pipes are respectively arranged at both ends of the heat dissipation pipes. The flower plates are plates with holes adapted to the ends of the heat dissipation pipes. The heat dissipation pipes are installed in the holes of the flower plates and extend out. A sealing plate is arranged on the outside of the flower plates, and the sealing plate seals the gap between the holes on the flower plates and the outer wall of the heat dissipation pipes.

[0011] The heat pipe is installed in the hole of the flower plate and extends out 8mm -15mm.

[0012] The heat dissipation pipes form k rows in the horizontal direction, and the heat dissipation pipes in each row are in the same vertical direction; the cleaning structure includes a cleaning chain II, which is located above the heat dissipation pipes, and the cleaning chain II corresponds to the gap between the heat dissipation pipes; the upper box body I and the upper box body II are respectively fixedly connected to the upper end of the chain I or the hanging rope of the rigid material, and the lower end of the chain I or the hanging rope of the rigid material is connected to the cleaning chain installation structure, and the cleaning chain installation structure is provided with n rows and m columns of cleaning chains II of rigid materials (n is a positive integer ≥2, and m is a positive integer ≥2), m=k+2, and the cleaning of rigid materials Chain II is arranged between any two adjacent columns of heat dissipation tubes arranged in parallel and between the heat dissipation tubes arranged at both ends and the shell. At least n cleaning chains II are arranged between each column of gaps formed between any two adjacent columns of heat dissipation tubes arranged in parallel or between each column of gaps formed between the heat dissipation tubes arranged at both ends and the shell. A reducer or a reducer motor is provided outside the shell. The reducer or the reducer motor is connected to the cleaning chain installation structure through a crank-connecting rod mechanism, so that the reducer or the reducer motor drives the crank-connecting rod mechanism to move, pushing the cleaning chain II installation structure to swing back and forth, thereby driving the chain to swing back and forth.

[0013] The rigid material cleaning chain II is 1-4 mm smaller in width direction than the gap formed between any two adjacent rows of parallel heat dissipation tubes or the gap formed between the heat dissipation tubes arranged at both ends and the housing.

[0014] The upper box body I and the upper box body II are respectively directly welded to the upper ends of the chain I or the lifting rope made of rigid material, or are connected to the upper ends of the chain I or the lifting rope made of rigid material through welded lifting rings.

[0015] The dust cleaning chain installation structure can be a fence type frame or a lattice type frame.

[0016] It comprises at least two heat exchangers, each heat exchanger comprises a shell, a smoke outlet and a smoke inlet, and the smoke outlet of one heat exchanger is connected to the smoke inlet of another heat exchanger through a connecting pipe.

[0017] The beneficial effect of the present invention is that the U-shaped airflow design of each heat exchanger of the flue gas heat exchanger for the smelting industry provided by the present application prolongs the travel of the flue gas in the heat exchanger, making its heat exchange effect better, and also makes the flue gas heat exchanger for the smelting industry provided by the present application smaller in size and smaller in floor space than the traditional surface cooler. Moreover, each heat exchanger is designed with a U-shaped airflow, and the flue gas is deflected upward after entering the ash hopper. The ash hopper is a relatively empty space, and the flow rate of the flue gas airflow in this space is reduced, which will allow larger particles in the flue gas airflow to settle. After settling, the dust concentration in the flue gas will be reduced, and the dust concentration of the flue gas entering the dust collector will be smaller than that of the original flue gas, so that the large particles of dust can be pre-separated or settled, and the dust concentration at the inlet of the dust collector can be reduced, which reduces the working pressure of the dust collector. The flue gas heat exchanger and system provided by the present application for the non-ferrous smelting industry has cooling air passing through the tube side and high-temperature flue gas passing through the shell side, that is, air enters the air inlet of the heat exchanger through the fan arranged on the side of the heat exchanger, and then enters the heat dissipation pipe from the end of the heat dissipation pipe to exchange heat with the high-temperature flue gas passing through the shell side of the heat exchanger, and then the air comes out from the air outlet of the heat exchanger, thereby achieving the purpose of reducing the flue gas temperature. Since the high-temperature flue gas passes through the shell side, the high-temperature flue gas forms dust accumulation on the outer wall of the heat dissipation pipe, so that the dust cleaning chain can be used to clean the dust accumulation on the outer wall of the heat dissipation pipe, and the cleaned dust accumulation falls into the ash hopper below the heat dissipation pipe, and the ash hopper is convenient for collecting the dust accumulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the heat exchanger system of the present invention.

[0019] Figure 2 It is a schematic diagram of the structure of a single heat exchanger.

[0020] Figure 3 yes Figure 2 Schematic diagram of the side view of the heat exchanger.

[0021] Figure 4 It is a structural diagram of the heat exchange tube.

[0022] Figure 5 It is a schematic diagram of the structure of the heat exchange tube when the middle box is divided into two.

[0023] Figure 6 It is a schematic diagram of the structural relationship between the heat exchange tube, the flower plate and the sealing plate.

[0024] Figure 7 It is a structural diagram of the dust cleaning structure.

[0025] Figure 8 It is a side view structural schematic diagram of the dust cleaning structure.

[0026] Fig. 9It is a schematic diagram of the connection structure relationship between the dust cleaning chain installation structure of the dust cleaning structure and the reducer or reducer motor.

[0027] Fig.10 It is an existing shell and tube surface cooler. DETAILED DESCRIPTION

[0028] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings. It is necessary to point out that this description is only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Technical personnel skilled in the art can make some non-essential improvements and adjustments based on the above-mentioned contents of the present invention.

[0029] like Figure 1-Figure 9 As shown, a flue gas heat exchanger for nonferrous smelting industry includes at least two heat exchangers 1, and the heat exchanger 1 includes a shell 2, a flue gas outlet 3 and a flue gas inlet 4; the heat exchanger shell 2 includes an upper box body 6, a middle box body 7, and an ash hopper 10 from top to bottom, the middle box body 7 is a heat dissipation box body, and at least two heat dissipation pipes 70 arranged in parallel are detachably arranged inside the middle box body 7, and a fan 71 is arranged on the side of the middle box body 7. The fan can be a variable frequency motor, and the cold air blown in by the fan 71 is connected to the air inlet of the heat exchanger, and the air inlet is connected to one end of the heat dissipation pipe 70, and the other end of the heat dissipation pipe is connected to the air outlet of the heat exchanger, and a dust cleaning mechanism 9 is arranged in the upper box body, and an ash hopper 10 is arranged below the heat dissipation pipe.

[0030] The cooling air goes through the tube side, and the high-temperature flue gas goes through the shell side, that is, the air enters the air inlet of the heat exchanger through the fan installed on the side of the heat exchanger, and then enters the heat pipe from the end of the heat exchanger to exchange heat with the high-temperature flue gas passing through the shell side of the heat exchanger, and then the air comes out from the air outlet of the heat exchanger, thereby reducing the flue gas temperature. Since the high-temperature flue gas goes through the shell side, the high-temperature flue gas forms dust on the outer wall of the heat exchanger, which makes it convenient for the dust cleaning chain to clean the dust on the outer wall of the heat exchanger. The cleaned dust falls into the ash hopper under the heat exchanger, which is convenient for the ash hopper to collect the dust. The ash hopper is funnel-shaped.

[0031] The hot air after heat exchange in the flue gas heat exchanger for the smelting industry provided in the present application can be recycled after coming out from the air outlet of the heat exchanger, such as returning to the furnace to compensate for heat or heating domestic water.

[0032] A partition plate 11 is provided in the heat exchanger 1, and the partition plate 11 separates the upper box 6 into an upper box I 60 and an upper box II 61, and the partition plate 11 separates the middle box 7 into a middle box I 72 and a middle box II 73. One of the upper box I 60 and the upper box II 61 is connected to the flue gas inlet 4, and the other is connected to the flue gas outlet 3. The middle box I 72 and the middle box II 73 are connected through the ash hopper 10. The flue gas inlet 4 and the flue gas outlet 3 are both located at the upper end of the heat exchanger 1.

[0033] Assuming that the upper box body Ⅰ60 is connected to the smoke inlet 4 and the middle box body Ⅰ72 respectively, and the upper box body Ⅱ61 is connected to the smoke outlet 3 and the middle box body Ⅱ73 respectively, the smoke first enters the upper box body Ⅰ60 from the smoke inlet of a heat exchanger, then enters the shell in the middle box body Ⅰ72 to exchange heat with the heat dissipation pipe 70 in the middle box body Ⅰ72, then enters the ash hopper 10, enters the shell of the middle box body Ⅱ73 from the ash hopper 10 to further exchange heat with the heat dissipation pipe 70 of the middle box body Ⅱ73, then enters the upper box body Ⅱ61, exits from the smoke outlet 3, enters the next heat exchanger 1 through the connecting pipe 5, and completes the heat exchange process until it exits from the smoke outlet 3 of the last heat exchanger 1. At this time, the path of the smoke in each heat exchanger is equivalent to a U-shape, so it can be considered as a U-shaped airflow. Therefore, the U-shaped airflow design of each heat exchanger of the flue gas heat exchanger for the smelting industry provided by the present application prolongs the travel of the flue gas in the heat exchanger, making its heat exchange effect better, and also makes the flue gas heat exchanger for the smelting industry provided by the present application smaller in size and smaller in floor space than the traditional surface cooler. Moreover, each heat exchanger is designed with a U-shaped airflow, and the flue gas is deflected upward after entering the ash hopper. The ash hopper is a relatively empty space, and the flow rate of the flue gas airflow in this space is reduced, which will allow larger particles in the flue gas airflow to settle. After settling, the dust concentration in the flue gas will be reduced, and the dust concentration of the flue gas entering the dust collector will be smaller than that of the original flue gas, so that the large particles of dust can be pre-separated or settled, and the dust concentration at the inlet of the dust collector can be reduced, which reduces the working pressure of the dust collector.

[0034] The heat dissipation pipe 70 is a flat pipe, and the narrow end or the curved end of the cross section of the flat pipe faces upward and downward.

[0035] The heat dissipation pipe 70 adopts a flat tube design to minimize the friction area between the smoke and the flat tube and maximize the contact area with the smoke. Figure 5 In the installation method of flat tubes, the flue gas flows vertically downward or upward. Under the guidance of the first row of flat tubes, the airflow passes through the channels between the flat tubes. The length of the narrow side end or curved side end of the flat tube's cross section is 10 times the length of the wide side end or plane end of the flat tube's cross section. When the wide side end or plane end of the flat tube's cross section faces upward or downward, it directly faces the high-temperature flue gas, and the friction area between the smoke and the flat tube is large. When the narrow side end or curved side end of the flat tube's cross section faces upward or downward, the friction area between the smoke and the flat tube is minimized, so it is not easy to wear.

[0036] The heat dissipation tubes 70 are arranged in a matrix in the middle box 7, and the length direction of the heat dissipation tubes 70 is perpendicular to the vertical direction. Therefore, the high-temperature flue gas of the heat exchanger is perpendicular to the cooling air, which is more convenient for the heat exchange between the two.

[0037] Both ends of the heat dissipation tube 70 are provided with flower plates 74 for fixing the heat dissipation tube. The flower plates 74 are plates with holes corresponding to the ends of the heat dissipation tube 70. The heat dissipation tube 70 is installed in the holes of the flower plates 74 and extends out. A sealing plate 75 is provided on the outside of the flower plates. The sealing plate 75 can be a stamping part. The sealing plate 75 seals the gap between the hole on the flower plate and the outer wall of the heat dissipation tube. This makes it easy to fix and disassemble the heat dissipation tube 70. When the heat dissipation tube 70 is replaced, the corresponding heat dissipation tube can be removed for replacement, and the heat dissipation tube of the entire heat exchanger does not need to be replaced.

[0038] When the partition plate 11 separates the middle box into middle box I 72 and middle box II 73, the flower plate 74 at each end may be a whole, or a flower plate 74 may be provided at each end of the heat dissipation pipe 70 in the middle box I 72 and the middle box II 73.

[0039] Each heat dissipation tube 70 is respectively covered with sealing plates 75 at both ends to seal the gap between the outer wall of the corresponding heat dissipation tube and the hole on the flower plate. Therefore, when a heat dissipation tube needs to be replaced, it is convenient to only remove the sealing plates at both ends of the corresponding heat dissipation tube, and then install a new heat dissipation tube and the corresponding removed sealing plates or newly replaced sealing plates, which makes replacement more simple and convenient.

[0040] The heat dissipation pipe 70 is installed in the hole of the flower plate 74 and extends out by 8mm-15mm, for example, it can extend out by 10mm, so as to facilitate the replacement of the heat dissipation pipe.

[0041] The heat dissipation tubes 70 form k rows in the horizontal direction, and the heat dissipation tubes 70 in each row are in the same vertical direction; the cleaning mechanism 9 includes a cleaning chain II 92 for removing the soot on the outer wall of the heat dissipation tube 70; the upper box body 6 is fixedly connected to the upper end of the chain I or the hanging rope 90 made of rigid material, and the lower end of the chain I or the hanging rope 90 made of rigid material is connected to the cleaning chain installation structure 91, and the cleaning chain installation structure 91 is provided with n rows and m columns of rigid material cleaning chains II 92 (n is a positive integer ≥2, and m is a positive integer ≥2), m=k+2, and the rigid material cleaning chain II 92 is arranged between any two adjacent parallel rows of heat dissipation tubes 70 and between the heat dissipation tubes 70 arranged at both ends and the shell, and any At least n cleaning chains II 92 are arranged between each gap 15 formed between two adjacent columns of parallel heat dissipation tubes or between each gap formed between the heat dissipation tubes arranged at both ends and the shell; a reducer or reducer motor 93 is provided outside the shell, and the reducer or reducer motor 93 is connected to the cleaning chain mounting structure 91 through a crank-connecting rod mechanism 94, so that the reducer or reducer motor drives the crank-connecting rod mechanism to move, pushing the chain mounting structure 91 to swing back and forth, thereby driving the cleaning chain II 92 to swing back and forth in the gap formed between two adjacent columns of parallel heat dissipation tubes 70 or the gap formed between the heat dissipation tubes 70 arranged at both ends and the shell, so as to achieve the purpose of cleaning the dust accumulated on the outer wall of the heat dissipation tube. The lower end of the cleaning chain II 92 is preferably 5-10cm longer than the lower end of the heat pipe 70, and the upper end is preferably 5-10cm longer than the upper end of the heat pipe 70, so that the cleaning chain II 92 can clean the outer wall of each end heat pipe during the swinging process. In addition, in order to make the cleaning chain II 92 produce greater friction on the outer wall of the heat pipe when cleaning dust, the speed reducer or speed reducer motor 93 has a lower operating frequency, so that the swing amplitude of the cleaning chain II 92 is slower, so that the chain will not have a large friction with the outer wall of the heat pipe due to excessive speed, which will reduce the service life of the heat pipe.

[0042] The steel cleaning chain II 92 is 1-4 mm smaller in width than the gap between any two adjacent parallel rows of heat dissipation tubes 70 or the gap between the heat dissipation tubes and the housing at both ends. This makes it easier for the steel cleaning chain II 92 to swing and clean the outer wall of the heat dissipation tube 70.

[0043] The upper box 6 is directly welded to the upper end of the rigid chain I or the hanging rope 90, or is connected to the upper end of the rigid chain I or the hanging rope through a welded hanging ring 95. The cleaning chain installation structure is directly welded to the upper end of the cleaning chain II 92, or is connected to the rigid cleaning chain II 92 through a welded hanging ring 95. The hanging ring 95 can be a circular ring or a U-shaped ring.

[0044] The dust cleaning chain installation structure 91 can be a fence-type frame or a grid-type frame. For example, the dust cleaning chain installation structure can be in the shape of a "well" or a "field".

[0045] When the partition plate 11 divides the upper box body into the upper box body I 60 and the upper box body II 61, dust cleaning mechanisms 9 for cleaning the heat dissipation pipes 70 can be respectively arranged in the upper box body I 60 and the upper box body II 61; alternatively, dust cleaning chain installation structures 91 can be respectively arranged in the upper box body I 60 and the upper box body II 61, and the dust cleaning chain II 92 is installed. Then, there is a speed reducer or a speed reducer motor outside the heat exchanger shell, and the speed reducer or the speed reducer motor is respectively connected to the dust cleaning chain installation structures 91 in the upper box body I 60 and the upper box body II 61 through a crank and connecting rod mechanism. Thus, the speed reducer or the speed reducer motor drives the crank and connecting rod mechanism 94 to move, pushing the chain installation structures 91 in the upper box body I 60 and the upper box body II 61 to swing reciprocally respectively, so as to drive the chains to swing reciprocally in the gaps formed between adjacent two rows of parallel arranged heat dissipation pipes 70 in the upper box body I 60 and the upper box body II 61 or in the gaps formed between the heat dissipation pipes arranged at both ends and the shell, achieving the purpose of cleaning the dust accumulated on the outer walls of the heat dissipation pipes 70.

[0046] A flue gas heat exchanger for the non-ferrous smelting industry includes at least two heat exchangers 1. The flue gas outlet 3 of one heat exchanger is connected to the flue gas inlet 4 of another heat exchanger through a connecting pipe 5. The connecting pipe 5 can include two obliquely upward pipes, which are cross-connected at the upper end. The lower ends of the two obliquely upward pipes are respectively connected to different heat exchangers 1, and the included angle between the two obliquely upward pipes is 60°.

[0047] The process flow of high-temperature flue gas is as follows: Figure 1 As shown, a flue gas heat exchanger for the non-ferrous smelting industry is composed of two heat exchangers. The flue gas from the smelting furnace enters from the flue gas inlet of the first heat exchanger, exchanges heat with the cold air in the heat dissipation pipes 70 in the first heat exchanger, then comes out from the flue gas outlet of the first heat exchanger, and then enters the flue gas inlet of the second heat exchanger through the connecting pipe, exchanges heat with the heat dissipation pipes in the second heat exchanger, comes out from the flue gas outlet of the second heat exchanger, and then enters the dust collector.

[0048] A temperature measuring point I 12 is provided at the flue gas inlet of the first heat exchanger through which the flue gas passes. The temperature measuring point I 12 can be provided with a temperature detector or / and a temperature sensor; a temperature measuring point II 13 is provided on the connecting pipe 5. The temperature measuring point II 13 can be provided with a temperature detector or / and a temperature sensor; a temperature measuring point III 14 is provided at the flue gas outlet of the last heat exchanger through which the flue gas passes. The temperature measuring point III 14 can be provided with a temperature detector or / and a temperature sensor.

[0049] If there are two heat exchangers, the control logic mainly refers to the control system of the heat exchanger. For example, the temperature detectors or / and temperature sensors at several temperature measuring points are connected to the PLC controller respectively. If the fan is equipped with a frequency conversion controller or the fan is a frequency conversion fan, the PLC controller is connected to the frequency conversion controller of each heat exchanger fan respectively. The temperature sensor transmits the temperature signal to the PLC controller at any time. The PLC controls the fan frequency converter according to the feedback data requirements, so that: for example, the flue gas temperature is 600℃ and needs to be reduced to 200±5℃. The outlet temperature of the first heat exchanger is designed to be 400℃, which is the connecting pipe temperature, and the outlet temperature of the second heat exchanger is 200℃. When designing a heat exchanger, the heat exchange area and air volume are designed with a margin, mainly to prevent the inlet operating temperature from increasing instantaneously. Figure 7 When the temperature measurement point II is close to 400℃, the fan of the first heat exchanger runs at full load. When the temperature is close to 200℃, the fan of the first heat exchanger stops working or the fan of the second heat exchanger stops working. For every 4℃ decrease in the temperature feedback from the temperature measurement point II, the fan frequency of the first heat exchanger decreases by 1Hz, and vice versa. The principle of the temperature measurement point III is similar to that of the temperature detection II. It mainly controls the fan frequency of the second heat exchanger and feeds back the temperature in real time. It can be achieved that when the ambient temperature decreases, the fan frequency of the heat exchanger also decreases, while ensuring that the outlet temperature is close to a constant temperature.

[0050] Therefore, the present application uses automated electronic control logic to reduce the operator's workload and can implement natural air temperature changes to achieve automatic control. The structural design of the flue gas heat exchanger for the smelting industry provided by the present application can also more accurately control the temperature, providing more favorable conditions for the design of the back-end dust collector, while also saving the cost of the dust collector. Moreover, the flue gas heat exchanger system for the smelting industry provided by the present application is provided with multi-point temperature measurement feedback, controls the fan air volume, and accurately controls the outlet flue gas temperature.

[0051] The motor of the cleaning structure of the present application can also be connected to the PLC, so that the cleaning structure of the present application can make the cleaning structure run regularly by controlling the running time of the motor, and can also be pressure-differential controlled: if the user chooses the pressure-differential control method, the air pipes must be led to the pressure detection device such as a pressure sensor at the inlet and outlet of the flue gas channel of the heat exchanger respectively. The pressure sensor is connected to the PLC, and the pressure sensor transmits the pressure signal to the PLC controller at any time. The PLC controls the fan inverter according to the feedback data requirements. If the flue gas channel is not blocked, the inlet and outlet pressure difference is within a certain range. When it exceeds the range, the flue gas channel is blocked and cleaning is required. The control method is: the pressure detection device feeds back the model to the PLC, and the PLC controls the cleaning mechanism. The user can also control the operation of the cleaning structure by manipulating the motor, and the electronic control part is humanized.

[0052] The above description is only a preferred embodiment of the present invention, but the protection scope of the present invention is not limited thereto. It should be pointed out that for those skilled in the art and any technician familiar with the technical field, without departing from the overall concept of the present invention, the technical solution and the inventive concept of the present invention are equivalently replaced or changed, and several changes and improvements are made, which should also be regarded as the protection scope of the present invention.

Claims

1. A flue gas heat exchanger for non-ferrous smelting industry, characterized by: The heat exchanger includes a shell, a flue gas outlet and a flue gas inlet; the heat exchanger shell includes an upper box, a middle box and an ash hopper from top to bottom, the middle box is a heat dissipation box, at least two parallel heat dissipation pipes are detachably arranged inside the middle box, a fan is arranged on the side of the middle box, the cold air blown in by the fan is connected to the air inlet, the air inlet is connected to one end of the heat dissipation pipe, and the other end of the heat dissipation pipe is connected to the air outlet, a dust cleaning mechanism is arranged in the upper box, and an ash hopper is arranged below the heat dissipation pipe; a partition plate is arranged in the heat exchanger, the partition plate separates the upper box into upper box I and upper box II, the partition plate separates the middle box into middle box I and middle box II, one of the upper box I and upper box II is connected to the flue gas inlet, and the other is connected to the flue gas outlet, and the middle box I and the middle box II are connected through the ash hopper; The heat dissipation pipes are arranged in a matrix in the middle box body I and the middle box body II, respectively. Both ends of the heat dissipation pipes are respectively provided with flower plates for fixing the heat dissipation pipes. The flower plates are plates with holes adapted to the ends of the heat dissipation pipes. The heat dissipation pipes are installed in the holes of the flower plates and extend out. A sealing plate is provided on the outside of the flower plates, and the sealing plate seals the gap between the holes on the flower plates and the outer wall of the heat dissipation pipes. The heat dissipation pipes form k rows in the horizontal direction, and the heat dissipation pipes in each row are in the same vertical direction; the dust cleaning mechanism includes a dust cleaning chain II, which is located above the heat dissipation pipes, and the dust cleaning chain II corresponds to the gap between the heat dissipation pipes; the upper box body I and the upper box body II are respectively fixedly connected to the upper end of the chain I or the hanging rope made of rigid material, and the lower end of the chain I or the hanging rope made of rigid material is connected to the dust cleaning chain installation structure, and the dust cleaning chain installation structure is provided with n rows and m columns of dust cleaning chains II made of rigid material, n is a positive integer ≥2, m is a positive integer ≥2, m=k+2, and the rigid material The cleaning chain II is arranged between any two adjacent columns of heat dissipation tubes arranged in parallel and between the heat dissipation tubes arranged at both ends and the shell. At least n cleaning chains II are arranged between each column of gaps formed between any two adjacent columns of heat dissipation tubes arranged in parallel or between each column of gaps formed between the heat dissipation tubes arranged at both ends and the shell. A reducer or a reducer motor is provided outside the shell. The reducer or the reducer motor is connected to the cleaning chain installation structure through a crank-connecting rod mechanism, so that the reducer or the reducer motor drives the crank-connecting rod mechanism to move, pushing the cleaning chain II installation structure to swing back and forth, thereby driving the chain to swing back and forth.

2. The flue gas heat exchanger for nonferrous smelting industry according to claim 1, characterized in that: The heat dissipation pipe is a flat pipe.

3. The flue gas heat exchanger for nonferrous smelting industry according to claim 1, characterized in that: The heat dissipation pipe is installed in the hole of the flower plate and extends out 8mm-15mm.

4. The flue gas heat exchanger for nonferrous smelting industry according to claim 1, characterized in that: The rigid material cleaning chain II is 1-4 mm smaller in width direction than the gap formed between any two adjacent rows of parallel heat dissipation tubes or the gap formed between the heat dissipation tubes arranged at both ends and the shell.

5. The flue gas heat exchanger for nonferrous smelting industry according to claim 1, characterized in that: The upper box body I and the upper box body II are respectively directly welded to the upper ends of the chain I or the lifting rope made of rigid material, or are connected to the upper ends of the chain I or the lifting rope made of rigid material through welded lifting rings.

6. The flue gas heat exchanger for nonferrous smelting industry according to claim 1, characterized in that: The dust cleaning chain installation structure is a fence-type frame or a lattice-type frame.

7. A flue gas heat exchanger system for non-ferrous smelting industry, characterized by: The invention comprises at least two heat exchangers according to any one of claims 1 to 6, wherein the heat exchanger comprises a shell, a smoke outlet and a smoke inlet, and the smoke outlet of one heat exchanger is connected to the smoke inlet of another heat exchanger through a connecting pipe.

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