High-performance low-carbon footprint type lean and rich liquid heat exchanger for chemical absorption trapping

Abstract

The invention discloses a high-performance low-carbon footprint type lean and rich liquid heat exchanger for chemical absorption trapping, which comprises a shell, a plurality of plate frames, guide pipes and connecting pipes, the plurality of plate frames are arranged in a shell cavity of the shell in two rows in an up-and-down staggered manner and are separated to form an S-shaped hot liquid flow channel; the head end and the tail end of each hot liquid flow channel are used for inputting or outputting hot fluid through connecting pipes penetrating out of the shell, each plate frame is internally provided with an S-shaped cold liquid flow channel, and every two adjacent plate frames located in the same row are connected in an end-to-end mode through a guide pipe. The plate frames located at the head end and the tail end of each row input or output cold fluid through the guide pipes penetrating out of the shell, efficient heat transfer between the lean liquid and the rich liquid can be achieved, and meanwhile the risk that a high-viscosity absorbent is accumulated and blocked in the pipeline can be reduced so that the cleaning frequency can be reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of chemical heat exchange equipment, in particular to the technical field of rich and lean liquid heat exchangers. Background Art

[0002] The CCUS process refers to Carbon Capture, Utilization and Storage technology, which usually uses a phase change absorbent to absorb carbon dioxide in flue gas in an absorption tower; this process aims to capture carbon dioxide from industrial emission sources and utilize or store it, thereby reducing greenhouse gas emissions and mitigating climate change.

[0003] In the CCUS process, the influence of temperature has a direct impact on the capture rate and absorption capacity of the absorption tower; this is because the absorption reaction is usually an exothermic reaction, and an increase in temperature will reduce the absorption capacity of the phase change absorbent; the rich and lean liquid heat exchanger is a heat exchange equipment used to adjust the temperature of the phase change absorbent in the CCUS process, which can achieve heat recovery (the rich liquid coming out of the absorption tower has a higher temperature, while the lean liquid coming out of the regeneration tower has a lower temperature; through the rich and lean liquid heat exchanger, the heat of the rich liquid can be transferred to the lean liquid, thereby recovering heat and reducing the energy consumption of the system), optimize the absorption efficiency (the lean liquid needs to be cooled before entering the absorption tower, and the rich liquid needs to be heated before entering the regeneration tower; through the rich and lean liquid heat exchanger, the temperatures of the lean liquid and the rich liquid can be adjusted to reach the optimal operating conditions, thereby improving the capture efficiency of carbon dioxide), and reduce energy consumption (through heat recovery, the rich and lean liquid heat exchanger can reduce the heating load of the regeneration tower and the cooling load of the absorption tower, thereby reducing the energy consumption of the entire system).

[0004] Rich and lean liquid heat exchangers usually include shell-and-tube heat exchangers (such as a shell-and-tube heat exchanger with publication number CN117588972A and a shell-and-tube heat exchanger with publication number CN104949552B) and wound-tube heat exchangers (such as a wound-tube heat exchanger with publication number CN109253634A), etc.; in the process of capturing carbon dioxide by chemical absorption method, the performance of the rich and lean liquid heat exchanger has an important impact on the capture rate and energy consumption of the entire system; however, for shell-and-tube heat exchangers, due to their traditional straight-tube design, high-viscosity fluids are prone to form laminar boundary layers during flow in the tubes, resulting in increased flow resistance and reduced flow velocity; this will not only lead to a decrease in thermal efficiency, but also easily cause the phase change absorbent to accumulate in the pipeline, and even block the pipeline in severe cases, greatly increasing the operating cost; wound-tube heat exchangers often have the problem of high construction cost. Summary of the Invention

[0005] The object of the present invention is to solve the problems in the prior art, and a high-performance low-carbon footprint rich and lean liquid heat exchanger for chemical absorption capture is proposed. It can not only achieve efficient heat transfer between the rich and lean liquids, but also reduce the risk of accumulation and blockage of high-viscosity absorbents inside the pipeline to reduce the cleaning frequency.

[0006] To achieve the above object, the present invention provides a high-performance low-carbon footprint rich and lean liquid heat exchanger for chemical absorption capture, which includes a housing, plate frames, ducts and nozzles. A number of the plate frames are arranged in two rows in a staggered manner up and down in the housing cavity of the housing and partitioned to form an S-shaped hot liquid flow channel. The head and tail ends of the hot liquid flow channel are respectively input or output hot fluids through nozzles passing through the housing. An S-shaped cold liquid flow channel is provided in each of the plate frames. Adjacent two plate frames in the same row are connected end to end of the cold liquid flow channels through ducts. The plate frames at the head and tail ends of each row respectively input or output cold fluids through ducts passing through the housing.

[0007] Preferably, disturbing convex structures are respectively provided on the surfaces of a number of plate frames near the outlet end of the hot liquid flow channel.

[0008] Preferably, the disturbing convex structures are hemispherical, cylindrical or trapezoidal.

[0009] Preferably, the plate frame includes a cover plate, a base groove, a baffle plate, a joint and a sealing ring. The cover plate is detachably closed at the notch of the base groove and jointly encloses a groove cavity with the base groove. The cold liquid flow channel is formed by partitioning a number of baffle plates arranged in two rows in a staggered manner up and down in the groove cavity. Joints communicating with the groove cavity and detachably connected to the ducts are respectively provided on the cover plate and the base groove. The sealing ring is located at the adjacent surface of the cover plate and the base groove.

[0010] Preferably, a number of groove body fastening seats are provided along the inner edge of the notch of the base groove. Through holes of the cover plate corresponding to each of the groove body fastening seats are provided on the cover plate. The cover plate and the base groove are connected together by a number of first fasteners passing through the through holes of the cover plate and screwed into the groove body fastening seats. Each of the first fasteners does not protrude from the surface of the cover plate through a counterbore of the cover plate.

[0011] Preferably, a ring groove portion is further provided at the notch of the base groove. The sealing ring is filled in the ring groove portion.

[0012] Preferably, a movable plate is further included. The movable plate is detachably connected to the cover plate. The disturbing convex structures are evenly distributed on the movable plate.

[0013] Preferably, the movable plate is placed on the cover plate along the sinking opening of the cover body and does not protrude from the surface of the cover plate. A plurality of cover body screw holes are provided above the sinking opening of the cover body. Plate body through holes corresponding to each cover body screw hole one by one are provided on the movable plate. The cover plate and the movable plate are connected together by a plurality of second fasteners passing through the plate body through holes and screwed into the cover body screw holes. Each of the second fasteners does not protrude from the surface of the movable plate through the plate body counterbore.

[0014] Preferably, the sinking opening of the cover body communicates with the outer edge and has a chute at the edge. The cover plate has a slide rail that cooperates with the chute.

[0015] Preferably, the flow direction of the cold fluid is opposite to the flow direction of the hot fluid.

[0016] Advantages of the present invention: 1) By arranging several plate frames in two rows, upper and lower, in a staggered manner in the outer shell to form an S-shaped external baffle space for the hot fluid to flow through, using a conduit to connect the S-shaped cold liquid flow channels of each plate frame end to end for the cold fluid to flow through, and adopting a countercurrent heat exchange design, compared with traditional heat exchangers, it can achieve efficient heat exchange between rich and lean liquids in a shorter time (improving the heat exchange efficiency), and can also effectively reduce the probability of pipeline blockage (reducing the maintenance cost of the equipment and improving the operation stability at the same time); 2) By adding disturbing convex structures in the shape of hemispheres, cylinders or trapezoids on the surfaces of several plate frames near the outlet end of the hot liquid flow channel, the efficient heat exchange capacity and anti-blocking performance of the equipment can be further improved (prolonging the service life of the equipment); 3) By using a movable plate detachably connected to the cover plate to carry the disturbing convex structure, it is convenient to adjust the flow disturbing performance of the disturbing convex structure in real time according to actual use requirements; 4) From the perspective of low carbon footprint, since the present invention greatly improves the heat transfer efficiency, it can significantly reduce the energy consumption of the equipment, reduce the carbon emissions generated by energy consumption, and at the same time the anti-blocking ability reduces the energy and water resource consumption in the cleaning process (reducing the resource and energy consumption brought by equipment replacement and frequent maintenance, and reducing the additional energy consumption caused by absorbent adhesion); 5) By adding a cover body counterbore, a cover body sinking opening and a plate body counterbore, the first fastener, the movable plate and the second fastener do not protrude from the cover plate, avoiding direct scouring of the first fastener, the movable plate and the second fastener by the liquid flow, and effectively improving the connection stability between the cover plate and the base groove and the movable plate respectively.

[0017] The features and advantages of the present invention will be described in detail through embodiments in conjunction with the drawings. Description of the Drawings

[0018] Figure 1 It is the front view of Embodiment 1; Figure 2 It is a schematic assembly diagram of the plate frame and the conduit in the first embodiment; Figure 3 It is a schematic assembly diagram of the plate frame, the conduit and the disturbing convex structure in the second embodiment; Figure 4 It is the front view of the plate frame in the third embodiment; Figure 5 It is the left view of the plate frame in the third embodiment; Figure 6 It is Figure 5 The schematic structural diagram when the cover plate is removed; Figure 7 It is a schematic assembly diagram of the plate frame, the disturbing convex structure and the movable plate in the fourth embodiment; Figure 8 It is the left view of the plate frame in the third embodiment; Figure 9 It is a schematic assembly diagram of the disturbing convex structure and the movable plate in the fourth embodiment; Figure 10 It is the life cycle system boundary diagram of the first embodiment; In the figure: 1 - outer shell, 2 - plate frame, 21 - cover plate, 211 - cover body through hole, 212 - cover body counterbore, 213 - cover body sinking opening, 214 - cover body screw hole, 215 - chute, 22 - base groove, 221 - sealing ring, 222 - annular groove part, 23 - baffle plate, 24 - joint, 25 - sealing ring, 3 - conduit, 4 - connecting pipe, 5 - disturbing convex structure, 6 - movable plate, 61 - plate body through hole, 62 - plate body counterbore, 63 - slide rail. Detailed implementation manners

[0019] The first embodiment: Referring to Figures 1 to 2 , this embodiment includes an outer shell 1, a plate frame 2, a conduit 3 and a connecting pipe 4. Several pieces of the plate frame 2 are arranged in two rows in a staggered manner up and down in the cavity of the outer shell 1 and partition to form an S-shaped hot fluid flow channel. The head and tail ends of the hot fluid flow channel are respectively input or output hot fluid through the connecting pipe 4 penetrating the outer shell 1. An S-shaped cold fluid flow channel is provided in each piece of the plate frame 2. The cold fluid flow channels of adjacent two pieces of the plate frame 2 in the same row are connected end to end by the conduit 3. The plate frames 2 at the head and tail ends of each row respectively input or output cold fluid through the conduit 3 penetrating the outer shell 1; compared with the straight channels in the traditional shell-and-tube heat exchanger, the degree of flow deflection of the hot fluid flow channel can be optimized according to the staggered arrangement mode of each piece of the plate frame 2, so that the hot fluid frequently changes the flow direction during the flow, increasing the degree of turbulence (the increase in turbulence can increase the heat transfer coefficient, strengthen the heat transfer and shorten the fluid residence time), and efficiently reducing the hot fluid to the temperature required when entering the absorption tower.

[0020] The flow direction of the cold fluid is opposite to that of the hot fluid; this countercurrent heat exchange mode can maintain a large temperature difference between the cold fluid and the hot fluid, thereby improving the heat exchange uniformity and efficiency.

[0021] The working process of this embodiment: During operation, the hot fluid, as Figure 1 shown by the arrow direction, first enters the outer shell 1 along the connecting pipe 4 and flows along the hot liquid flow path to exchange heat with each plate frame 2, and then leaves the outer shell 1 along the connecting pipe 4 after heat exchange; in addition, the cold fluid, as Figure 2 shown by the arrow direction, first enters the outer shell 1 along the conduit 3 and flows through each plate frame 2 through the cold liquid flow path to exchange heat with the hot fluid, and then leaves the outer shell 1 along the conduit 3 after heat exchange.

[0022] In addition, the efficient heat exchanger also reduces the carbon footprint of the production cycle, specifically reflected in that the baffle design improves the residence time of the fluid, enhances the heat exchange efficiency, and reduces materials such as stainless steel required for the manufacture of the heat exchanger; refer to Figure 10 , the carbon emissions in each stage can be calculated using the following formula; a) The quantification of the carbon footprint in the raw material and auxiliary material acquisition stage is shown in the following formula (1): (1); In the formula, C1 represents the carbon footprint in the raw material and auxiliary material acquisition stage, and the unit is tCO2e; M i represents the total input in the acquisition stage of the i th material, and the unit is t, m 3 or L; EF i represents the carbon emission factor in the acquisition stage of the i th material, and the unit is tCO2e / t, tCO2e / m 3 or tCO2e / L.

[0023] b) The quantification of the carbon footprint in the raw material and auxiliary material transportation stage is shown in the following formula (2): (2); In the formula, C 2 represents the carbon footprint in the raw material and auxiliary material transportation stage, and the unit is tCO2e; T i represents the total transportation volume in the transportation stage of the i th material, and the unit is t, m 3 or L; D i represents the transportation distance in the transportation stage of the i th material, and the unit is km; EF i represents thei The carbon emission factor corresponding to a material transportation method, with the unit of tCO2e / (t×km); c) The carbon footprint quantification in the heat exchanger manufacturing stage is shown in the following formula (3): (3); In the formula, C 3 represents the carbon footprint in the heat exchanger manufacturing stage, with the unit of tCO2e; E i represents the total consumption of the i th substance or energy in the heat exchanger manufacturing stage, with the unit of t, m 3 , L or kWh; EF i represents the carbon emission factor of the i th substance or energy consumed in the heat exchanger manufacturing stage, with the unit of tCO2e / t, tCO2e / m 3 , tCO2e / L or tCO2e / MWh.

[0024] Example 2: Referring to Figure 3 , on the surfaces of several plate frames 2 near the outlet end of the hydrothermal flow channel, disturbing convex structures 5 are respectively provided; during the flow of the absorbent, the disturbing convex structures 5 can further disturb the fluid boundary layer, enhance the heat exchange effect, and effectively prevent the high-viscosity absorbent from adhering to the surface of the plate frame 2; the disturbing convex structures 5 are hemispherical; among them, the hemispherical design endows the disturbing convex structures 5 with advantages in processing and manufacturing (can be efficiently realized through casting or machining, without complex molds), good structural strength and durability (the curved surface design can evenly disperse the pressure to the entire surface, improving the erosion resistance), and self-cleaning and low-maintenance characteristics (the streamlined surface can reduce the attachment of dirt, and can also cooperate with the anti-adhesion coating to further reduce the maintenance frequency); in addition, the disturbing convex structures 5 can also be cylindrical or trapezoidal, so as to flexibly adjust the height-width ratio according to requirements, so that the absorbent can stably generate periodic vortices and enhance fluid mixing even in the laminar flow state.

[0025] Others are the same as in Example 1.

[0026] Example 3: Referring to Figures 3 to 6, the plate frame 2 includes a cover plate 21, a base groove 22, a baffle plate 23, a joint 24 and a sealing ring 25. The cover plate 21 is detachably closed at the notch of the base groove 22 and jointly encloses a groove cavity with the base groove 22. The cold liquid flow channel is formed by separating and blocking several baffle plates 23 arranged in two rows and staggered up and down in the groove cavity. The cover plate 21 and the base groove 22 are respectively provided with joints 24 that are communicated with the groove cavity and detachably connected to the conduit 3. The sealing ring 25 is located at the adjacent surface of the cover plate 21 and the base groove 22. Arranging the baffle plate 23 in the plate frame 2 can guide the cold fluid to flow along a specific path, avoid the occurrence of flow dead corners, further enhance the disturbance of the fluid inside the plate frame 2, ensure that the phase change absorbent can flow smoothly even in a high-viscosity state, prevent blockage, and ensure the stable operation of the equipment.

[0027] The base groove 22 is provided with several groove body fastening seats 221 along the inner edge of the notch. The cover plate 21 is provided with cover body through holes 211 corresponding to each groove body fastening seat 221 one by one. The cover plate 21 and the base groove 22 are connected together by several first fasteners passing through the cover body through holes 211 and screwed into the groove body fastening seats 221. Each of the first fasteners does not protrude from the surface of the cover plate 21 through the cover body counterbore 212.

[0028] The base groove 22 is further provided with an annular groove portion 222 at the notch. The sealing ring 25 is filled in the annular groove portion 222.

[0029] Others are the same as in the first embodiment.

[0030] After using for a period of time, the cover plate 21 can be opened as required to clean the base groove 22 and its internal structure.

[0031] Embodiment 4: Refer to Figures 7 to 9 , on the surfaces of several plate frames 2 near the outlet end of the hot liquid flow channel, disturbing convex structures 5 are respectively provided.

[0032] The disturbing convex structure 5 is in a hemispherical, cylindrical or trapezoidal shape.

[0033] It further includes a movable plate 6. The movable plate 6 is detachably connected to the cover plate 21. The disturbing convex structures 5 are evenly distributed on the movable plate 6.

[0034] The movable plate 6 is placed on the cover plate 21 along the sinking opening 213 of the cover body and does not protrude from the surface of the cover plate 21. A plurality of cover body screw holes 214 are provided above the sinking opening 213 of the cover body. Plate body through holes 61 corresponding to each of the cover body screw holes 214 are provided on the movable plate 6. The cover plate 21 and the movable plate 6 are connected together by a plurality of second fasteners passing through the plate body through holes 61 and screwed into the cover body screw holes 214. Each of the second fasteners does not protrude from the surface of the movable plate 6 through the plate body counterbore 62.

[0035] The sinking opening 213 of the cover body communicates with the outer edge and has a sliding groove 215 at the edge. The cover plate 21 has a sliding rail 63 that matches the sliding groove 215.

[0036] Others are the same as in Embodiment 3.

[0037] Before use, the movable plate 6 can be replaced according to requirements to change the shape of the disturbing convex structure 5.

[0038] The above embodiments are illustrative of the present invention, not limiting of the present invention. Any solution obtained by simply transforming the present invention belongs to the protection scope of the present invention.

Claims

1. A high-performance low-carbon footprint rich / lean liquid heat exchanger for chemical absorption capture, characterized in that: It includes a housing (1), a plate frame (2), a conduit (3) and a connection pipe (4). Several of the said plate frames (2) are arranged in two staggered rows up and down in the housing cavity of the housing (1) and partitioned to form an S-shaped hot liquid flow channel. The head and tail ends of the said hot liquid flow channel are respectively connected through the connection pipes (4) passing through the housing (1) to input or output hot fluid. An S-shaped cold liquid flow channel is provided in each of the said plate frames (2). The cold liquid flow channels of adjacent two of the said plate frames (2) in the same row are connected end to end through the conduit (3). The plate frames (2) at the head and tail ends of each row are respectively connected through the conduits (3) passing through the housing (1) to input or output cold fluid.

2. The high-performance low-carbon footprint rich and lean liquid heat exchanger for chemical absorption capture according to claim 1, wherein: On the surfaces of several plate frames (2) near the outlet end of the said hot liquid flow channel, disturbing convex structures (5) are respectively provided.

3. The high-performance low-carbon footprint rich / lean liquid heat exchanger for chemical absorption capture according to claim 2, characterized in that: The said disturbing convex structures (5) are hemispherical, cylindrical or trapezoidal.

4. The high-performance low-carbon footprint lean-rich liquid heat exchanger for chemical absorption capture according to claim 3, wherein: The said plate frame (2) includes a cover plate (21), a base groove (22), a baffle plate (23), a joint (24) and a sealing ring (25). The cover plate (21) is detachably closed at the notch of the base groove (22) and jointly encloses a groove cavity with the base groove (22). The cold liquid flow channel is formed by partitioning of several baffle plates (23) arranged in two staggered rows up and down in the groove cavity. Joints (24) communicating with the groove cavity and detachably connected to the conduit (3) are respectively provided on the cover plate (21) and the base groove (22). The sealing ring (25) is located at the adjacent surface of the cover plate (21) and the base groove (22).

5. The high-performance low-carbon footprint rich / lean liquid heat exchanger for chemical absorption capture according to claim 4, wherein: Several groove body fastening seats (221) are provided along the inner edge of the notch of the said base groove (22). Cover body through holes (211) corresponding to each of the groove body fastening seats (221) are provided on the cover plate (21). The cover plate (21) and the base groove (22) are connected together through several first fasteners passing through the cover body through holes (211) and screwed into the groove body fastening seats (221). Each of the said first fasteners does not protrude from the surface of the cover plate (21) through the cover body counterbores (212).

6. The high-performance low-carbon footprint lean-rich liquid heat exchanger for chemical absorption capture according to claim 4, characterized in that: A ring groove portion (222) is further provided at the notch of the said base groove (22). The sealing ring (25) is filled in the ring groove portion (222).

7. The high-performance low-carbon footprint lean-rich liquid heat exchanger for chemical absorption capture according to claim 4, characterized in that: It further includes a movable plate (6). The movable plate (6) is detachably connected to the cover plate (21). The said disturbing convex structures (5) are evenly distributed on the movable plate (6).

8. The high-performance low-carbon footprint rich / lean liquid heat exchanger for chemical absorption capture according to claim 7, characterized in that: The said movable plate (6) is placed on the cover plate (21) along the cover body sinking opening (213) and does not protrude from the surface of the cover plate (21). Several cover body screw holes (214) are provided on the cover body sinking opening (213). Plate body through holes (61) corresponding to each of the cover body screw holes (214) are provided on the movable plate (6). The cover plate (21) and the movable plate (6) are connected together through several second fasteners passing through the plate body through holes (61) and screwed into the cover body screw holes (214). Each of the said second fasteners does not protrude from the surface of the movable plate (6) through the plate body counterbores (62).

9. The high-performance low-carbon footprint rich / lean liquid heat exchanger for chemical absorption capture according to claim 8, characterized in that: The sinking opening (213) of the cover body communicates with the outer edge and has a sliding groove (215) at the edge, and the cover plate (21) has a sliding rail (63) that cooperates with the sliding groove (215).

10. The high-performance low-carbon footprint lean-rich liquid heat exchanger for chemical absorption capture according to any one of claims 1 to 9, characterized in that: The flow direction of the cold fluid is opposite to that of the hot fluid.

Images