Cooling tower filler partition optimization arrangement and heat and mass transfer cooperative strengthening method

Abstract

The invention discloses a cooling tower filler partition optimization arrangement and heat and mass transfer cooperative strengthening method. The method comprises the following steps: obtaining radial wind speed distribution; determining setting ranges of a core area, a middle area and an edge area according to the radial wind speed distribution; and different fillers are respectively arranged in the core area, the middle area and the edge area. According to the application, the distribution of the core area, the middle area and the edge area is carried out through the distribution of the radial wind speed, then different fillers are arranged according to the layout of the wind speed, local improvement is respectively carried out, and the heat and mass transfer effect of the cooling tower is optimized based on the improvement.

Description

TECHNICAL FIELD

[0001] The application relates to a cooling tower filler partition optimization arrangement and heat and mass transfer synergistic enhancement method. BACKGROUND

[0002] The radial distribution of the wind volume in a large natural draft counterflow cooling tower is significantly uneven, and the wind volume peak often appears at a ring belt with a radius of about 1 / 3 of the tower radius. If uniform fillers and uniform water distribution are still used, two types of mismatching are prone to occur: (1) high wind volume ring belt (about 1 / 3 of the tower radius): under the uniform filler type, the local wind speed is high, the local pressure drop is large, but the specific surface area and heat transfer capacity of the original filler are insufficient, and wind penetration and insufficient contact are prone to occur. (2) low wind volume area (core / near wall): the local wind speed is low, and the local pressure drop is small; if the filler resistance in this area is increased, the airflow will be further inhibited and over-wetting will be caused.

[0003] Therefore, it is necessary to use partition differentiated fillers and water distribution / air supplement to match the resistance distribution and capacity distribution to the local wind volume distribution.

[0004] The existing scheme mostly replaces the uniform filler specifications in the whole tower, or only makes local water / air supplement, and lacks partition differentiated filler + water distribution / air supplement synergistic design based on the wind volume distribution law, so it is difficult to balance the pressure drop, heat transfer and operation stability. SUMMARY

[0005] In order to solve the above problems, the application provides a cooling tower filler partition optimization arrangement and heat and mass transfer synergistic enhancement method, which comprises the following steps: Obtain the radial wind speed distribution; Determine the setting range of the core area, the intermediate area and the edge area according to the radial wind speed distribution; Different fillers are arranged in the core area, the intermediate area and the edge area. The application determines the distribution of the core area, the intermediate area and the edge area according to the distribution of the radial wind speed, then sets different fillers according to the layout of the wind speed, respectively improves the local area, and optimizes the heat and mass transfer effect of the cooling tower based on the improvement.

[0006] Preferably, the radial wind speed distribution is obtained in the following manner: A basic filler is arranged in the tower, a wind speed sensor is arranged above the basic filler in the tower to measure the radial distribution of the wind speed, the maximum wind speed V max in the tower and the change of the wind speed from the center to the tower wall direction are obtained; A threshold wind speed V t1 and the position thereof are obtained, the position of the threshold wind speed V t1 is set as the demarcation line of the intermediate area and the edge area; The core wind speed V​t2 and the location, core wind speed V t2 The location is set as the boundary between the core area and the intermediate area, and the maximum wind speed V max is set in the core area.

[0007] Preferably, the V t1 = 0.1-0.2V max ; The V t2 = 0.4-0.45V max .

[0008] Preferably, the core area uses ANCS composite wave fillers; The intermediate area is PVC small-pitch filler; the pitch between filler sheets is not more than 25mm; The edge area retains the basic filler; the basic filler is a honeycomb filler. The present application first obtains the radial wind speed based on the basic filler, then replaces the basic filler in the intermediate area with PVC small-pitch filler, and replaces the core area with ANCS composite wave filler to improve the mass transfer and heat transfer effect.

[0009] Preferably, the following improvements are made to the intermediate area, core area and edge area respectively, and the improvement range of each time is not more than 2%: The intermediate area increases water distribution nozzles, and the number and flow of the water distribution nozzles are set as follows: the number of the water distribution nozzles is not less than 4 and is uniformly distributed in the circumferential direction; The core area is provided with a wind supplement pipe; The edge area optimizes the water inlet pipe to reduce the end pressure drop, and the optimization of the water inlet pipe includes increasing the hole diameter of the water inlet pipe and / or the opening degree of the water distribution valve.

[0010] Preferably, it further includes a subsequent optimization verification process: According to the Merkel / Poppe model and CFD coupling to build KaV / L response surface, and according to the multi-objective constraint of “GLR uniformity-KaV / L-ΔP” to optimize: The GLR uniformity is improved by not less than 20%; Or KaV / L is improved by 15%-20%; The additional pressure drop ΔP in the tower is increased by not more than 10%; Adjust until the outlet water temperature is reduced by 0.5-0.8 ℃ compared with the temperature before adjustment. The present application first replaces the filler, then increases the water distribution nozzle in the intermediate area, optimizes the water inlet pipe in the edge area, and sets the wind supplement pipe in the core area, and the replacement gradient is controlled within 2%, and the outlet water temperature is finally reduced by 0.5-0.8 ℃ after the subsequent optimization verification.

[0011] Preferably, the filler is arranged on a filler supporting device.

[0012] Preferably, the filler supporting device comprises a plurality of transversely arranged main beams, a plurality of support columns arranged at the lower part of the main beams, two longitudinally arranged secondary beams arranged on the main beams, and a plurality of U-shaped clamps for fixing the cooling tower filler arranged between the two secondary beams; the U-shaped clamp comprises a transverse rod bridging between the two secondary beams, vertical rods arranged at both ends of the transverse rod, the vertical rods passing through the secondary beams, a bottom bolt rod arranged at the bottom of the vertical rod, and a fastening nut arranged on the bottom bolt rod at the lower part of the secondary beam. The main beam and the secondary beam are used to assist in forming an overall supporting structure, the overall structure adopts an assembled structure, then the cooling tower filler is arranged on the secondary beam and fixed by the U-shaped clamp, the stability of the overall structure is better, and the partition replacement can be performed according to the arrangement of the U-shaped clamp, thereby simplifying the entire maintenance process.

[0013] Preferably, a cutting-resistant guard plate is arranged at the position of the vertical rod corresponding to the cooling tower filler; an obliquely arranged oblique support rod is arranged at the bottom of the main beam at both ends, and the oblique support rod at the middle is connected by a bottom connecting bolt or welded. A main beam connecting hole is arranged at the position of the main beam corresponding to the secondary beam, a secondary beam connecting hole is arranged at the position of the secondary beam corresponding to the main beam, and a plurality of fixed connecting bolts are arranged between the main beam connecting hole and the secondary beam connecting hole; the main beam connecting hole is a strip-shaped hole, the secondary beam connecting hole is a strip-shaped hole, the axis of the main beam connecting hole and the axis of the secondary beam connecting hole are arranged vertically; the fixed connecting bolt comprises a bolt body, a stop washer and a fixed nut are arranged at both sides of the bolt body. Two strip-shaped holes are used for connection, and then the fixed connecting bolt is used for connection, which can be adjusted within a certain range, and the assembly is more convenient to use.

[0014] Preferably, the support column comprises a column body, a concrete pad is arranged at the upper part of the column body, a adjustable nut block is fixedly arranged on the concrete pad, an adjusting bolt is threadedly connected to the middle part of the adjustable nut block, and an insertion positioning groove is arranged at the position of the main beam corresponding to the adjusting bolt; an insulating gasket is arranged at the abutting portion between the main beam and the secondary beam. The concrete pad of different heights can be replaced according to the used part, and the height is finely adjusted by combining the adjustable nut block and the adjusting bolt, so that the device supporting height can be continuously adjusted by fine adjustment + coarse adjustment.

[0015] The application can bring the following beneficial effects: 1. The application distributes the core area, the middle area and the edge area by the distribution of the radial wind speed, then arranges different fillers according to the layout of the wind speed, respectively improves the local area, and optimizes the heat and mass transfer effect of the cooling tower based on the improvement.

[0016] 2. The application first replaces the filler, then increases the water distribution nozzle in the middle zone, optimizes the import water pipe in the edge zone, and sets the air supplement pipe in the core zone, and the replacement gradient control is 2%, combined with the subsequent optimization verification, the outlet water temperature is finally reduced by 0.5-0.8 ℃.

[0017] 3. The application adopts main beam and secondary beam to form a whole support structure, the whole adopts assembly type structure, then sets cooling tower filler on the secondary beam, and fixes by U-shaped clamp, the stability of the whole structure is better, and the partition replacement can be carried out according to the arrangement of the U-shaped clamp, so that the whole maintenance process is simplified.

[0018] 4. The filler support device of the application can replace concrete pads of different heights according to the used parts, and the height of the adjustable nut block and the adjusting bolt is adjusted, so that the fine adjustment + coarse adjustment cooperation can be realized, BRIEF DESCRIPTION OF DRAWINGS

[0019] The drawings described herein are used to provide further understanding of the application, and constitute a part of the application. The schematic embodiments of the application and their descriptions are used to explain the application, and do not constitute improper limitation on the application. In the drawings: Figure 1 It is a flowchart of the application.

[0020] Figure 2 It is a structural schematic diagram of the filler support device.

[0021] Figure 3 It is a structural schematic diagram of the main beam and the supporting column cooperating with the support.

[0022] Figure 4 It is a schematic diagram of the cooling tower filler fixing.

[0023] Figure 5 It is Figure 4 Another perspective view.

[0024] Figure 6 It is a structural schematic diagram of the main beam and the secondary beam connection.

[0025] Figure 7 It is a structural schematic diagram of the main beam and the supporting part abutting. DETAILED DESCRIPTION

[0026] In order to clearly explain the technical characteristics of the scheme, the application will be described in detail below through specific implementation manner, and combined with its drawings.

[0027] A cooling tower filler partition optimization arrangement and heat transfer and mass transfer synergistic enhancement method, as shown in Figure 1 The method comprises the following steps: S1 Obtain radial wind speed distribution: The radial wind speed distribution is obtained in the following way: A base packing is arranged in the tower, and a wind speed sensor is arranged above the base packing in the tower to measure the wind speed along the radial direction thereof, so as to obtain the maximum wind speed V max and the change of the wind speed from the center to the wall of the tower; S2 Determine the setting range of the core area, the intermediate area and the edge area according to the radial wind speed distribution: Obtain the threshold wind speed V t1 and the position thereof, the threshold wind speed V t1 The position thereof is set as the demarcation line between the intermediate area and the edge area; Obtain the core wind speed V t2 and the position thereof, the core wind speed V t2 The position thereof is set as the demarcation line between the core area and the intermediate area, and the maximum wind speed V max is arranged in the core area.

[0028] The V t1 =0.1-0.2V max ; The V t2 =0.4-0.45V max .

[0029] S3 Arrange different packings in the core area, the intermediate area and the edge area respectively: The core area adopts ANCS composite wave packing; The intermediate area is PVC small-pitch packing, and the pitch between packing sheets is not more than 25 mm; The edge area retains the base packing, and the base packing is honeycomb packing.

[0030] S4 Improvement of partition: The following improvements are made for the intermediate area, the core area and the edge area respectively, and the amplitude of each improvement is not more than 2%: The intermediate area increases water distribution nozzles, and the number and flow of the water distribution nozzles are arranged in the following way: the number of the water distribution nozzles is not less than 4, and the water distribution nozzles are arranged uniformly in the circumferential direction; The core area is provided with a supplementary air pipe; The edge area optimizes the water inlet pipe to reduce the end pressure drop, and the optimization of the water inlet pipe includes increasing the aperture of the water inlet pipe and / or the opening degree of the water distribution valve.

[0031] S5 Subsequent optimization verification: The KaV / L response surface is constructed by coupling the Merkel / Poppe model with CFD, and optimization is performed according to the multi-objective constraint of "GLR homogeneity - KaV / L - ΔP": GLR uniformity improvement is no less than 20%; Or KaV / L increase by 15%–20%; The additional pressure drop ΔP inside the tower increases by no more than 10%; Adjust until the outlet water temperature is 0.5–0.8 ℃ lower than before adjustment.

[0032] For the support of the packing, such as Figures 2-7 As shown, the packing material is installed on the packing support device, which includes several horizontally arranged main beams 1, several support columns 2 at the lower part of the main beams 1, two longitudinally arranged secondary beams 3 on the main beams 1, and several U-shaped clamps 5 for fixing the cooling tower packing material 4 between the two secondary beams 3; the U-shaped clamps 5 include a horizontal bar 6 spanning between the two secondary beams 3, and vertical bars 7 at both ends of the horizontal bar 6. The vertical bars 7 pass through the secondary beams 3, and a bottom bolt bar 8 is provided at the bottom of the vertical bar 7. A fastening nut 9 is provided on the bottom bolt bar 8 at the lower part of the secondary beam 3.

[0033] A cut-resistant guard plate 10 is installed at the position of the vertical rod 7 corresponding to the cooling tower packing 4. An inclined support rod 11 is installed at the bottom of the main beam 1 at both ends. The inclined support rod 11 is connected to the inclined support rod 11 in the middle by bottom connecting bolts or welding.

[0034] A main beam connection hole is provided at the position of the main beam 1 corresponding to the position of the secondary beam 3, and a secondary beam connection hole 12 is provided at the position of the secondary beam 3 corresponding to the position of the main beam 1. A plurality of fixing bolts 13 are provided between the main beam connection hole and the secondary beam connection hole 12. The main beam connection hole is a strip-shaped hole, and the secondary beam connection hole 12 is a strip-shaped hole. The axis of the main beam connection hole and the axis of the secondary beam connection hole 12 are perpendicular to each other. Each fixing bolt 13 includes a bolt body 14, and a locking washer 15 and a fixing nut 16 are respectively provided on both sides of the bolt body 14.

[0035] The support column 2 includes a column body 17, a concrete pad 18 is provided on the upper part of the column body 17, an adjustable nut block 19 is fixedly provided on the concrete pad 18, an adjusting bolt 20 is threadedly connected to the middle of the adjustable nut block 19, and an insertion positioning groove is provided on the main beam 1 at the position corresponding to the adjusting bolt 20. An insulating gasket is provided at the abutment between the main beam 1 and the secondary beam 3.

[0036] In assembly, first set up the support column 2, can be replaced according to the part used, different height of concrete cushion 18, combined with the height of adjustable nut block and adjusting bolt 20 fine tuning, so that can be through the fine tuning + coarse tuning cooperation, realize the device support height can be continuously adjustable, then set up the main beam 1 on the support column 2, set up the secondary beam 3 on the main beam 1, and then the bolt body 14 passes through the secondary beam connecting hole 12, the main beam connecting hole, then the two sides are fixed by using the stop washer 15 and the fixed nut 16, and then the cooling tower filler 4 is set up from the secondary beam 3, and then the vertical rod 7 of the U-shaped clamp 5 is set up through the secondary beam 3, and then the fastening nut 9 is connected to the bolt rod 8 set on the bottom.

[0037] The above only for the embodiment of the present application, and is not used to limit the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. within the spirit and principle of the present application shall be included in the scope of claims of the present application.

Claims

1. A method for synergistic enhancement of cooling tower packing zoning and heat and mass transfer, characterized in that: Includes the following steps: Obtain radial wind speed distribution; The setting range of the core area, intermediate area and edge area is determined based on the radial wind speed distribution; Different fillers are used in the core area, middle area and edge area.

2. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 1, characterized in that: The radial wind speed distribution is obtained as follows: A foundation packing is installed inside the tower. An anemometer is placed above the foundation packing to measure the wind speed distributed radially along it, thus obtaining the maximum wind speed V inside the tower. max And the wind speed change from the center towards the tower wall; Obtain the threshold wind speed V t1 And its location, threshold wind speed V t1 Its location is set as the boundary between the middle and edge areas; Obtain core wind speed V t2 And its location, core wind speed V t2 The location is set as the dividing line between the core area and the intermediate area, and the maximum wind speed V max It is located in the core area.

3. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 2, characterized in that: The V t1 =0.1-0.2V max ; The V t2 =0.4-0.45V max .

4. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 2, characterized in that: The core area uses ANCS composite wave filler; The intermediate area is filled with PVC fine-pitch filler; the spacing between the filler sheets does not exceed 25mm. The edge area retains the basic filler; the basic filler is a honeycomb filler.

5. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 1, characterized in that: The following improvements will be made to the middle area, core area, and edge area, with each improvement not exceeding 2%: The intermediate zone is equipped with water distribution nozzles. The number of water distribution nozzles and the flow rate of the water distribution nozzles are set as follows: the number of water distribution nozzles is not less than 4, and they are evenly distributed in the circumferential direction. The core area is equipped with a makeup air duct; The edge area is optimized to introduce water pipes and reduce the pressure drop at the end. The optimization of the water pipes includes increasing the orifice diameter of the water pipes and / or the opening degree of the water distribution valves.

6. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 5, characterized in that: This also includes the process of subsequent optimization and verification: The KaV / L response surface is constructed by coupling the Merkel / Poppe model with CFD, and optimization is performed according to the multi-objective constraint of "GLR homogeneity - KaV / L - ΔP": GLR uniformity improvement is no less than 20%; Or KaV / L increase by 15%–20%; The additional pressure drop ΔP inside the tower increases by no more than 10%; Adjust until the outlet water temperature is 0.5–0.8 ℃ lower than before adjustment.

7. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 1, characterized in that: The packing material is mounted on the packing support device.

8. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 7, characterized in that: The packing support device includes several horizontally arranged main beams, several support columns at the bottom of the main beams, two longitudinally arranged secondary beams on the main beams, and several U-shaped clamps for fixing the cooling tower packing between the two secondary beams. The U-shaped clamps include a horizontal bar spanning between the two secondary beams, vertical bars at both ends of the horizontal bar, the vertical bars passing through the secondary beams, bottom bolt bars at the bottom of the vertical bars, and fastening nuts on the bottom bolt bars at the bottom of the secondary beams.

9. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 8, characterized in that: Cut-resistant protective plates are installed at the positions of the vertical rods corresponding to the cooling tower packing; inclined support rods are installed at the bottom of the main beams at both ends, and the inclined support rods are connected to the inclined support rods in the middle by bottom connecting bolts or welding. A main beam connection hole is provided at the position of the main beam corresponding to the secondary beam, and a secondary beam connection hole is provided at the position of the secondary beam corresponding to the main beam. A plurality of fixing bolts are provided between the main beam connection hole and the secondary beam connection hole. The main beam connection hole is a strip hole, and the secondary beam connection hole is a strip hole. The axis of the main beam connection hole and the axis of the secondary beam connection hole are perpendicular to each other. The fixing bolt includes a bolt body, and a locking washer and a fixing nut are respectively provided on both sides of the bolt body.

10. The method for zonal optimization of cooling tower packing and synergistic enhancement of heat and mass transfer as described in claim 8, characterized in that: The support column includes a column body, a concrete pad on the upper part of the column body, an adjustable nut block fixed on the concrete pad, an adjusting bolt threaded to the middle of the adjustable nut block, an insertion positioning groove on the main beam corresponding to the position of the adjusting bolt, and an insulating gasket at the abutment between the main beam and the secondary beam.

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