Efficient heat exchange device

Abstract

The efficient heat exchange device comprises a dust remover and a heat exchanger, the heat exchanger is arranged at the top of the dust remover, a dust discharging opening in the bottom end of the dust remover is communicated with a dust collecting box, a shell of the dust remover is of an interlayer structure, a cooling liquid cavity is formed in the top end of the dust remover, and the interlayer structure is communicated with the cooling liquid cavity. An exhaust port of the dust remover is communicated with a shell pass inlet of the heat exchanger through an air inducing pipe, a cooling liquid outlet communicated with the interior of the interlayer structure is formed in the bottom of the dust remover, a tube pass inlet and a shell pass outlet are formed in the upper end of the heat exchanger, and a smoke inlet is formed in the upper portion of the dust remover. Dust particles are removed through the dust remover, flue gas subjected to dust removal enters the shell pass of the heat exchanger through the air inducing pipe, cooling water enters the shell pass of the heat exchanger for heat exchange and cooling, the cooling water subjected to heat exchange enters the interlayer structure of the dust remover through the cooling liquid cavity, and the flue gas is subjected to heat exchange and pre-cooling synchronously in the dust removal process. And the efficient heat exchange effect is achieved.

Description

Technical Field

[0001] This utility model relates to the field of chemical production equipment technology, specifically to a high-efficiency heat exchange device. Background Technology

[0002] The pyrite-to-acid production line mainly includes a raw material section, a roasting section, and a purification section. The purification section receives furnace gas at approximately 360°C from the roasting section, which undergoes two stages of dust removal before entering a power wave tower for spray washing. The washed flue gas (temperature between 50-65°C) then enters an air cooling tower to further cool it to below 35°C. Most existing air cooling towers are packed towers. Although the dust content is already low after two stages of dust removal and power wave tower washing, some impurities remain in the acid mist, easily causing blockage of the packed tower and affecting production efficiency. Therefore, further dust removal and cooling are needed before the flue gas enters the packed tower to reduce the operating pressure on the subsequent packed tower. Currently, dust collectors and heat exchangers are typically arranged horizontally and independently, connected by pipelines. The flue gas first enters the dust collector and then the heat exchanger for pre-cooling, which not only occupies a large area but also has low heat exchange efficiency.

[0003] Chinese Patent Publication No. CN205537236U discloses an integrated dust removal and heat exchange energy-saving device, comprising: an upper shell-and-tube heat exchanger, a lower cyclone dust collector, and a diffuser tube. The shell-and-tube heat exchanger and the cyclone dust collector are connected as a single unit via the diffuser tube and a flange. The shell-and-tube heat exchanger includes a shell, heat exchange tubes, baffles, tube sheet, flanges, tube box, cold water inlet pipe, hot water outlet pipe, and exhaust pipe. The cyclone dust collector includes a shell, top plate, riser pipe, tangential inlet pipe, and dust discharge pipe. High-temperature exhaust gas enters the shell of the cyclone dust collector through the tangential inlet pipe. After centrifugal separation, the dust in the exhaust gas is discharged through the dust discharge pipe. The purified gas is decelerated and diffused through the riser pipe and diffuser tube before entering the tube side of the shell-and-tube heat exchanger to heat the fluid outside the tubes. In this patent, the flue gas enters the tube side of the shell-and-tube heat exchanger after passing through a cyclone dust collector, while cold water enters the shell side. Due to the large flow rate and low density of the flue gas, it needs to flow at high speed to maintain turbulence if it flows through the tube side, which leads to a sharp increase in tube pressure drop and a low flue gas heat transfer coefficient, thus affecting the heat exchange efficiency. Utility Model Content

[0004] The main objective of this invention is to overcome the deficiencies of the aforementioned background technology and provide a highly efficient heat exchange device.

[0005] To achieve the above objectives, this utility model proposes a high-efficiency heat exchange device, comprising a dust collector and a heat exchanger. The heat exchanger is located at the top of the dust collector. The dust collector's bottom ash discharge port is connected to a dust collection box. The dust collector's shell is a sandwich structure. A cooling liquid chamber is provided at the top of the dust collector. The sandwich structure is connected to the cooling liquid chamber. The heat exchanger's tube-side outlet is connected to the cooling liquid chamber. The dust collector's exhaust port is connected to the heat exchanger's shell-side inlet via an exhaust pipe. The bottom of the dust collector is provided with a cooling liquid outlet connected to the interior of the sandwich structure. The heat exchanger's upper end is provided with a tube-side inlet and a shell-side outlet. The dust collector's upper part is provided with a flue gas inlet. The flue gas to be cooled enters the inner wall of the dust collector tangentially through the flue gas inlet, forming a high-speed rotating airflow to remove dust particles larger than 5μm, preventing large dust particles from entering the subsequent heat exchanger and causing blockage. The clean flue gas enters the shell side of the heat exchanger through the duct, and the external cooling water enters the tube side from the tube side inlet at the top of the heat exchanger. It exchanges heat with the rotating and rising clean flue gas in a countercurrent to cool the flue gas. The cooled water after heat exchange enters the cooling liquid chamber below and flows downward into the jacket structure to exchange heat with the flue gas in the dust collector for pre-cooling. Through the synergistic effect of the two-stage heat exchange, the heat exchange efficiency can be further improved.

[0006] In a further optimized technical solution, the heat exchanger shell is equipped with a continuous spiral baffle plate, with a pre-existing gap between the continuous spiral baffle plate and the heat exchanger shell. An annular dust collection groove is fitted onto the heat exchanger shell, and several through-holes are formed around the side wall of the heat exchanger shell, communicating with the annular dust collection groove. As the flue gas spirals upward within the heat exchanger, centrifugal force throws residual fine powder particles towards the heat exchanger shell wall, where they fall along the gaps in the continuous spiral baffle plate into the lower annular dust collection groove for self-cleaning, improving anti-dust accumulation capability and thus enhancing heat exchange efficiency.

[0007] In a further optimized technical solution, tube sheets are provided at both ends of the heat exchanger, and a guide ring is provided on the bottom tube sheet. The guide ring guides fine powder impurities into the annular dust collection tank.

[0008] In a further optimized technical solution, the top of the guide ring is provided with an outward-curved edge, which is inclined downwards. The downward-curved edge can effectively guide fine powder impurities into the annular dust collection trough, while preventing particles in the annular dust collection trough from being thrown upwards.

[0009] In a further optimized technical solution, several dust discharge ports are provided around the bottom of the annular dust collection trough, and each of the dust discharge ports is detachably equipped with a sealing plate. Removing the sealing plate facilitates the discharge of fine powder stored in the annular dust collection trough.

[0010] In a further optimized technical solution, the sandwich structure is equipped with spiral guide vanes. These vanes cause the cooling water within the sandwich structure to swirl downwards, increasing the turbulence intensity and ensuring that the water flow covers the entire wall surface of the sandwich structure.

[0011] In a further optimized technical solution, the spiral direction of the spiral guide vane is opposite to the direction of the external vortex inside the dust collector. This allows the reverse centrifugal force of the cooling water to counteract the radial force generated by the external vortex of the flue gas, suppressing vibration transmission.

[0012] In a further optimized technical solution, the exhaust duct is spiral-shaped, and the spiral directions of both the exhaust duct and the continuous spiral baffle are consistent with the direction of the internal vortex inside the dust collector. By adopting a co-directional spiral structure, the airflow continues to flow in the original direction of rotation after leaving the dust collector, avoiding vortex dissipation and kinetic energy loss.

[0013] In a further optimized technical solution, valves are provided at the flue gas inlet, the induced draft duct, the shell-side outlet, the tube-side inlet, and the coolant outlet. These valves control the opening and closing of the corresponding pipes and inlets / outlets, or regulate the volume of gas entering or leaving the pipes.

[0014] In a further optimized technical solution, the dust collector's casing is equipped with support feet. These support feet provide support for the entire device.

[0015] The beneficial effects of this invention include: flue gas enters the dust collector through the flue gas inlet to remove dust particles larger than 5μm, preventing large dust particles from entering subsequent processes and causing blockages; the dust-removed flue gas is guided into the shell side of the heat exchanger through the duct, where it rotates and rises. Simultaneously, cooling water enters the tube side of the heat exchanger from the tube side inlet at the top, counter-currently exchanging heat with the rotating, rising clean flue gas to cool it. The cooled flue gas is then discharged from the shell side outlet to the next process, while the cooled water enters the lower cooling liquid chamber. The flue gas then flows downwards into the sandwich structure to exchange heat with the external vortex flue gas for pre-cooling. Compared with existing technologies, the flue gas to be cooled can meet the flow requirements at a lower flow rate. The pressure drop of the flue gas in the shell side is low, and the flue gas rotates and washes the tube bundle during the upward process, generating a radial velocity gradient and destroying the thermal boundary layer, which can improve the heat transfer efficiency at the same flow rate. At the same time, the cooling water after heat exchange enters the sandwich structure of the dust collector and flows from top to bottom, indirectly exchanging heat with the high-temperature external vortex flue gas in the dust collector. Through the synergistic effect of two-stage heat exchange, a high-efficiency heat exchange effect is achieved. Attached Figure Description

[0016] Figure 1 This is an overall schematic diagram of the heat exchange device in an embodiment of this utility model.

[0017] Figure 2 This is a schematic diagram of the interior of the heat exchange device after being cut open in an embodiment of this utility model.

[0018] Figure 3 yes Figure 2 A magnified view of a portion of point A in the middle.

[0019] Figure 4 This is an overall schematic diagram of the annular dust collection trough in an embodiment of this utility model.

[0020] Figure 5 This is a schematic diagram of the bottom of the annular dust collection trough in an embodiment of this utility model.

[0021] Figure 6 This is a schematic diagram of the sandwich structure in an embodiment of this utility model.

[0022] Reference numerals: 1. Dust collector; 101. Ash discharge port; 102. Jacket structure; 1021. Spiral guide vane; 103. Coolant chamber; 104. Exhaust port; 105. Coolant outlet; 106. Flue gas inlet; 2. Heat exchanger; 201. Shell-side inlet; 202. Tube-side inlet; 203. Shell-side outlet; 204. Continuous spiral baffle; 205. Annular dust collection trough; 2051. Dust discharge port; 2052. Sealing plate; 206. Through port; 207. Tube sheet; 208. Guide ring; 209. Outward flange; 3. Dust collection box; 4. Exhaust duct; 5. Valve; 6. Support foot. Detailed Implementation

[0023] To make the technical problems, technical solutions, and beneficial effects of the embodiments of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0024] It should be noted that when a component is referred to as "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as "connected to" another component, it can be directly connected to or indirectly connected to that other component. Furthermore, a connection can be for both fixing and circuit connection purposes.

[0025] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", and "outer" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0026] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of embodiments of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0027] Please see Figures 1 to 6This embodiment discloses a high-efficiency heat exchange device, which includes a dust collector 1 and a heat exchanger 2. The heat exchanger 2 is vertically installed on top of the dust collector 1 to reduce the floor space. A dust collection box 3 is connected to the ash discharge port 101 at the bottom of the dust collector 1. The shell of the dust collector 1 is configured as a sandwich structure 102. A cooling liquid chamber 103 is provided at the top of the dust collector 1. The upper end of the sandwich structure 102 is connected to the cooling liquid chamber 103. The tube-side outlet at the bottom of the heat exchanger 2 is connected to the cooling liquid chamber 103. The exhaust port 104 of the dust collector 1 is connected to the shell-side inlet 201 of the heat exchanger 2 through an exhaust pipe 4. A cooling liquid outlet 105 connected to the interior of the sandwich structure 102 is provided at the bottom of the shell of the dust collector 1. A tube-side inlet 202 and a shell-side outlet 203 are respectively provided at the upper end of the heat exchanger 2. A flue gas inlet 106 is provided at the upper part of the dust collector 1. Specifically, the dust collector 1 is a cyclone dust collector, and the heat exchanger 2 is a spiral baffle heat exchanger. Support feet 6 are provided on the shell of the dust collector 1 to form a stable support. Valves 5 are provided at the flue gas inlet 106, the exhaust pipe 4, the shell-side outlet 203, the tube-side inlet 202, and the coolant outlet 105. The valves 5 control the opening and closing of the corresponding pipes and inlets / outlets, or regulate the air volume. The exhaust port 104 of the dust collector 1 is located at the top center of the dust collector 1. The exhaust port 104 is not connected to the coolant chamber 103, but is led out to the side wall of the coolant chamber 103 through the exhaust pipe 4 and then connected to the shell-side inlet 201 at the bottom of the heat exchanger 2.In this embodiment, the flue gas to be cooled enters the inner wall of the dust collector 1 tangentially through the flue gas inlet 106, forming a high-speed rotating airflow. The rotating airflow spirals downward to form an outer vortex. The centrifugal force generated during the rotation throws dust particles toward the inner wall of the dust collector 1. The dust particles fall into the dust collection box 3 below under their own gravity, removing dust particles >5μm and preventing large dust particles from entering the heat exchanger 2 and causing blockage, thus affecting the heat exchange efficiency. After the rotating airflow descends to the bottom, it turns upward along the axial direction of the dust collector 1 to form an upward inner vortex and enters the exhaust port 104. It then enters the shell side of the heat exchanger 2 through the duct 4. Inside the shell side of the heat exchanger 2, it rotates and rises along the spiral baffle of the heat exchanger 2. At the same time, cooling water enters the tube side from the tube side inlet 202 at the top of the heat exchanger 2 and exchanges heat with the rotating and rising clean flue gas in a countercurrent manner to cool the flue gas. The cooled flue gas then exits from the exhaust port 104. The cooling water discharged from the shell-side outlet 203 enters the next process. After heat exchange, the cooling water enters the lower cooling liquid chamber 103 and flows downward into the jacket structure 102 to exchange heat with the flue gas in the outer vortex for pre-cooling. After flowing to the bottom of the jacket structure 102, the cooling water is discharged from the cooling liquid outlet 105. Compared with the prior art, since the shell-side flow cross-sectional area of ​​the heat exchanger 2 is larger, the flue gas to be cooled can meet the flow requirements even when it moves upward through the shell side of the heat exchanger at a lower flow rate. The pressure drop of the flue gas in the shell side is low, and the flue gas rotates and washes the tube bundle during the upward process, generating a radial velocity gradient and destroying the thermal boundary layer, which can improve the heat transfer efficiency at the same flow rate. At the same time, the cooling water after heat exchange enters the jacket structure 102 of the dust collector 1 and flows from top to bottom, indirectly exchanging heat with the high-temperature external vortex flue gas in the dust collector 1. The heat exchange efficiency is further improved through the synergistic effect of the two-stage heat exchange.

[0028] In a preferred embodiment, the shell of the heat exchanger 2 is provided with a continuous spiral baffle 204, with a gap reserved between the continuous spiral baffle 204 and the shell of the heat exchanger 2. An annular dust collection groove 205 is fitted on the shell of the heat exchanger 2, protruding from the shell of the heat exchanger 2. Several through ports 206 are opened around the side wall of the shell of the heat exchanger 2, and the several through ports 206 are connected to the annular dust collection groove 205. When the flue gas spirals upward in the shell side of the heat exchanger 2, the centrifugal force throws the residual fine powder toward the shell wall of the heat exchanger 2, and falls into the annular dust collection groove 205 below along the gap of the continuous spiral baffle 204, reducing the accumulation of dust on the outer surface of the tube bundle of the heat exchanger 2. The self-cleaning of the heat exchanger 2 improves its anti-dust accumulation ability, thereby improving the heat exchange efficiency.

[0029] In a preferred embodiment, tube sheets 207 are provided at both ends of the heat exchanger 2, and the space between the two tube sheets 207 is the shell-side space of the heat exchanger 2. A guide ring 208 is provided on the bottom tube sheet 207. When centrifugal force throws the residual fine powder toward the shell wall of the heat exchanger 2, the fine powder passes through the gap between the continuous spiral baffle 204 and the shell of the heat exchanger 2 under gravity and falls onto the guide ring 208 below. The guide ring 208 guides the fine powder into the annular dust collection tank 205, preventing the fine powder from accumulating.

[0030] In a specific example, an outwardly flanged edge 209 is provided at the top of the guide ring 208, and the outwardly flanged edge 209 is inclined downwards. With the outwardly flanged edge 209 inclined downwards, when fine powder falls onto the outwardly flanged edge 209, it can effectively slide into the annular dust collection groove 205. At the same time, the outwardly flanged edge 209 extends laterally into the annular dust collection groove 205, which can prevent the fine powder in the annular dust collection groove 205 from being thrown upwards.

[0031] In a specific example, several dust discharge ports 2051 are provided at the bottom of the annular dust collection trough 205, and sealing plates 2052 are detachably provided at the dust discharge ports 2051. When the machine stops, the fine powder stored in the annular dust collection trough 2055 can be discharged by removing the sealing plates 2052 and exposing the dust discharge ports 2051.

[0032] In a preferred embodiment, a spiral guide vane 1021 is provided inside the sandwich structure 102, and the spiral direction of the spiral guide vane 1021 is opposite to the direction of the external vortex inside the dust collector 1. The spiral guide vane 1021 causes the cooling water inside the sandwich structure 102 to swirl downwards, increasing the turbulence intensity of the cooling water, ensuring that the water flow covers the entire wall surface of the sandwich structure 102, improving the wall surface heat transfer coefficient, and thus improving the heat exchange effect; moreover, the spiral direction of the spiral guide vane 1021 is opposite to the direction of the external vortex inside the dust collector 1, so that the reverse centrifugal force of the cooling water can counteract the radial force generated by the external vortex of the flue gas, suppressing vibration transmission, avoiding resonance between the water flow and the flue gas flow in the same direction in the sandwich structure 102, and reducing the risk of structural fatigue.

[0033] In a preferred embodiment, the exhaust duct 4 is spiral-shaped, and the spiral directions of both the exhaust duct 4 and the continuous spiral baffle 204 are consistent with the direction of the internal vortex inside the dust collector 1. The rising airflow in the vortex inside the dust collector 1 has high tangential velocity and rotational angular momentum. The exhaust duct 4 adopts a co-directional spiral structure, allowing the airflow to continue flowing in the original rotation direction after leaving the dust collector 1, avoiding vortex dissipation and kinetic energy loss. Moreover, after the airflow enters the shell side of the heat exchanger 2, since the continuous spiral baffle 204 and the exhaust duct 4 rotate in the same direction, the flue gas can rise along the spiral flow channel without adjusting its direction after entering. Through the coordinated design of the flow field, the system pressure drop can be reduced, energy consumption can be saved, and heat exchange efficiency can be improved.

[0034] The above description, in conjunction with specific / preferred embodiments, provides a further detailed explanation of the present invention and should not be construed as limiting the specific implementation of the present invention to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the protection scope of the present invention. In the description of this specification, the reference to terms such as "an embodiment," "some embodiments," "preferred embodiment," "example," "specific example," or "some examples," etc., indicates that the specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the described specific features, structures, materials, or characteristics can be combined in a suitable manner in any one or more embodiments or examples. Without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification and the features of different embodiments or examples. Although embodiments of the present invention and their advantages have been described in detail, it should be understood that various changes, substitutions and alterations may be made herein without departing from the scope of protection of the patent application.

Claims

1. A high-efficiency heat exchange device, characterized in that, include: The dust collector and heat exchanger are provided. The heat exchanger is located at the top of the dust collector. The dust collection box is connected to the ash discharge port at the bottom of the dust collector. The shell of the dust collector is a sandwich structure. A cooling liquid chamber is provided at the top of the dust collector. The sandwich structure is connected to the cooling liquid chamber. The tube-side outlet of the heat exchanger is connected to the cooling liquid chamber. The exhaust port of the dust collector is connected to the shell-side inlet of the heat exchanger through an exhaust pipe. A cooling liquid outlet connected to the interior of the sandwich structure is provided at the bottom of the dust collector. A tube-side inlet and a shell-side outlet are respectively provided at the top of the heat exchanger. A flue gas inlet is provided at the top of the dust collector.

2. The high-efficiency heat exchange device as described in claim 1, characterized in that: The heat exchanger shell is provided with a continuous spiral baffle plate inside, and a gap is reserved between the continuous spiral baffle plate and the heat exchanger shell. An annular dust collection groove is fitted on the heat exchanger shell, and a plurality of passage openings are opened around the side wall of the heat exchanger shell, and the plurality of passage openings are connected to the annular dust collection groove.

3. The high-efficiency heat exchange device as described in claim 2, characterized in that: The heat exchanger has tube sheets at both ends, and a flow guide ring is provided on the tube sheet at the bottom.

4. The high-efficiency heat exchange device as described in claim 3, characterized in that: The top of the guide ring is provided with an outward flange, which is inclined downward.

5. The high-efficiency heat exchange device as described in claim 4, characterized in that: A plurality of dust discharge ports are provided around the bottom of the annular dust collection trough, and a sealing plate is detachably provided at each of the dust discharge ports.

6. The high-efficiency heat exchange device as described in claim 1, characterized in that: The sandwich structure is equipped with spiral guide vanes.

7. The high-efficiency heat exchange device as described in claim 6, characterized in that: The spiral direction of the spiral guide vane is opposite to the direction of the external vortex inside the dust collector.

8. The high-efficiency heat exchange device as described in claim 2, characterized in that: The exhaust duct is spiral-shaped, and the spiral direction of both the exhaust duct and the continuous spiral baffle is consistent with the direction of the internal vortex inside the dust collector.

9. The high-efficiency heat exchange device as described in claim 1, characterized in that: Valves are provided at the flue gas inlet, the exhaust pipe, the shell-side outlet, the tube-side inlet, and the coolant outlet.

10. The efficient heat exchange device as described in any one of claims 1 to 9, characterized in that: The dust collector is equipped with support feet on its casing.

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