A seawater desalination device facilitating leak point finding

Abstract

The application relates to the technical field of seawater desalination, in particular to a seawater desalination device facilitating leakage point searching, which comprises a power steam source, a desalination unit, a spraying unit, a condenser and an online conductivity monitor, the power steam source is arranged at the input end of the desalination unit and is used for providing steam to the desalination unit; the condenser is arranged at the output end of the desalination unit, and a detection unit is fixedly connected with the desalination unit; the spraying unit is used for spraying seawater into the desalination unit; the desalination unit comprises a plurality of evaporators, the plurality of evaporators are connected in series through connecting flanges, and a desalination water discharge pipe is arranged in the evaporator; the online conductivity monitor is arranged on the desalination water discharge pipe, and the online conductivity monitor is used for monitoring the conductivity of water flow in the desalination water discharge pipe in real time; through the processing scheme, the seawater desalination device leakage point can be quickly searched, and fresh water loss is reduced.

Description

Technical Field

[0001] This application relates to the field of seawater desalination technology, specifically to a seawater desalination device that facilitates the location of leaks. Background Technology

[0002] A seawater desalination plant is a device that uses steam to evaporate seawater to obtain fresh water. Its main structure is the evaporator, which mainly contains a seawater spraying system, heat exchange tubes, and a freshwater collection system. The function of the seawater spraying system is to evenly spray seawater onto the heat exchange tube bundle. The seawater flows onto the heat exchange tubes (usually made of aluminum alloy or titanium alloy), forming a water film. It is then evaporated by the steam inside the heat exchange tubes. The steam inside the heat exchange tubes condenses into water after heat exchange, collects in the water chamber, and is transported to the freshwater pump through pipelines.

[0003] The heat exchange tubes of a seawater desalination unit are subjected to harsh environments such as seawater and temperature fluctuations. Over time, the heat exchange tubes may become damaged or leak. Since the external environment is seawater, once damaged, seawater will enter the tubes through the leak. The inside of the heat exchange tubes is a channel for steam and desalinated water. When seawater comes into contact with and mixes with the desalinated water, it will contaminate the desalinated water and cause it to become substandard. In this case, the desalinated water cannot be recycled and must be discharged, and the seawater desalination unit must be shut down. Operation can only be resumed after the leak is found and eliminated.

[0004] However, large-scale seawater desalination plants have multiple evaporators, each with tens of thousands of heat exchange tubes. It is difficult to quickly and accurately locate the leaking heat exchange tube. If the leak cannot be found and eliminated for a long time, the seawater desalination plant cannot resume operation, resulting in a significant loss of freshwater. Utility Model Content

[0005] In order to quickly locate leaks in seawater desalination devices and reduce freshwater loss, this application provides a seawater desalination device that facilitates the location of leaks.

[0006] The seawater desalination device provided in this application, which facilitates the location of leaks, adopts the following technical solution:

[0007] The system includes a power steam source, a desalination unit, a spray unit, a condenser, and an online conductivity monitor. The power steam source is located at the input end of the desalination unit and is used to supply steam to the desalination unit. The condenser is located at the output end of the desalination unit. The spray unit is used to spray seawater into the desalination unit.

[0008] The desalination unit includes multiple evaporators, which are connected in series via connecting flanges.

[0009] The evaporator includes: an evaporator shell, heat exchange tubes, a demister, a desalinated water collection mechanism, and a concentrated brine collection pipe. Multiple heat exchange tubes are arranged in an array inside the evaporator shell, and the heat exchange tubes are arranged along the axial direction of the evaporator shell. The demister is located at the input end of the evaporator shell.

[0010] The spraying unit includes a seawater delivery pipe and multiple spray pipes, which are connected in parallel on the seawater delivery pipe. The spray pipes are respectively located in the inner cavities of the multiple evaporator shells and are positioned above the heat exchange tubes. The spray pipes are used to spray seawater onto the heat exchange tubes. The concentrated brine collection pipe is located at the bottom of the evaporator and is connected to the inner cavity of the evaporator shell.

[0011] The desalinated water collection mechanism includes a desalinated water collection tank and a desalinated water discharge pipe. The desalinated water collection tank is fixedly installed on the heat exchange tube near the output end of the evaporator shell, and the inner cavity of the desalinated water collection tank is connected to the heat exchange tube. One end of the desalinated water discharge pipe is connected to the bottom of the desalinated water collection tank, and the other end is connected to a desalinated water main pipe. Multiple desalinated water discharge pipes are connected in parallel on the desalinated water main pipe.

[0012] The online conductivity monitor is installed on the desalinated water discharge pipe and is used to monitor the conductivity of the water flow in the desalinated water discharge pipe in real time.

[0013] In one possible implementation, the conductivity monitor includes a display controller, a transmission circuit, and multiple conductivity electrodes. The multiple conductivity electrodes are respectively disposed on multiple desalinated water discharge pipes. Each conductivity electrode includes two parallel plates that extend into the inner cavity of the desalinated water discharge pipe. One end of the transmission circuit is connected to the conductivity electrode, and the other end is connected to the display controller. The display controller is used to display the resistivity of the desalinated water.

[0014] In one possible implementation, the conductivity monitor further includes an alarm device electrically connected to the display controller.

[0015] In one possible implementation, a concentrated brine discharge pipe is also included, and a plurality of concentrated brine collection pipes are connected in parallel on the concentrated brine discharge pipe; a flash tank is provided on the concentrated brine discharge pipe, and a plurality of flash tanks are connected in series through the concentrated brine discharge pipe;

[0016] The flash tank is equipped with a steam return pipe that extends into the inner cavity of the evaporator shell, and the outlet height of the steam return pipe is higher than the liquid level height inside the evaporator shell.

[0017] In one possible implementation, the condenser is disposed on the evaporator at the output end of the desalination unit, and the condenser includes a high-pressure steam discharge pipe, a non-condensable steam discharge pipe, and a vacuum suction device; the vacuum suction device is disposed outside the evaporator, and one end of the high-pressure steam discharge pipe is connected to the top of the heat exchange tube, and the other end is connected to the vacuum suction device.

[0018] One end of the non-condensable steam discharge pipe is connected to the top of the evaporator shell, and the other end is connected to the vacuum suction device.

[0019] In one possible implementation, a cooling water discharge pipe is provided at the bottom of the evaporator at the output end of the desalination unit, and the cooling water discharge pipe is connected to the inner cavity of the evaporator shell.

[0020] In one possible implementation, the sidewall of the desalinated water collection tank is provided with multiple end plates, which are made of transparent material.

[0021] The seawater desalination device provided in this application facilitates the location of leaks. During operation, an online conductivity monitor continuously monitors the resistivity of the desalinated water in the discharge pipe. By inserting two parallel plates into the discharge pipe, an electric potential is applied and the current is measured. The transmission circuit transmits the current data to the display controller, which calculates the conductivity based on the current data. When the conductivity exceeds a preset value, it can be determined that seawater is mixed in the desalinated water pipe. The display controller then transmits a signal to the alarm device to trigger an alarm. Operators can determine the location of the leak in the heat exchanger tube based on the position of the online conductivity monitor in the discharge pipe. The heat exchanger tube can be viewed through a transparent end plate, facilitating the precise location of the leak and enabling rapid identification of the leak point. This allows for quick replacement and repair of the leaking heat exchanger tube, reducing freshwater loss. Attached Figure Description

[0022] The accompanying drawings are provided to further understand this application and form part of the specification. They are used together with the embodiments of this application to explain this application and do not constitute a limitation thereof.

[0023] Figure 1 This is a schematic diagram of the overall structure of a seawater desalination device that facilitates the location of leaks, as described in this application.

[0024] Figure 2 This is a schematic diagram of the layout of an online conductivity monitor for a seawater desalination device that facilitates the location of leaks, as described in this application.

[0025] Figure 3 This is a schematic diagram of the end face of the evaporator of a seawater desalination device that facilitates the location of leaks, as described in this application.

[0026] Figure 4 This is a longitudinal cross-sectional view of the evaporator of a seawater desalination device that facilitates the location of leaks, as described in this application.

[0027] Figure Descriptions: 1. Power Steam Source; 2. Desalination Unit; 21. Evaporator; 211. Evaporator Shell; 212. Heat Exchange Tube; 213. Demister; 214. Desalinated Water Collection Mechanism; 2141. Desalinated Water Collection Tank; 2142. Desalinated Water Discharge Pipe; 2143. End Plate; 215. Concentrated Brine Collection Pipe; 216. Desalinated Water Main Pipe; 217. Concentrated Brine Discharge Pipe; 218. Flash Tank; 2181. Steam Return Pipe; 219. Cooling Water Discharge Pipe; 3. Spray Unit; 31. Seawater Delivery Pipe; 32. Spray Pipe; 4. Condenser; 41. High-Pressure Steam Discharge Pipe; 42. Non-Condensing Steam Discharge Pipe; 43. Vacuum Suction Device; 5. Online Conductivity Monitor; 51. Display Controller; 52. Conductivity Electrode; 53. Alarm Device. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] 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 this application, unless otherwise stated, "multiple" means two or more.

[0030] The following is in conjunction with the appendix Figure 1-4 This application will be described in further detail.

[0031] This application discloses a seawater desalination device that facilitates the location of leaks.

[0032] Reference Figures 1-4A seawater desalination device for easy leak location includes: a power steam source 1, a desalination unit 2, a spray unit 3, a condenser 4, and an online conductivity monitor 5. The desalination unit 2 includes multiple evaporators 21. In this embodiment, five evaporators 21 are connected in series via flanges, arranged from left to right as a first-effect evaporator 21 to a fifth-effect evaporator 21. The first-effect evaporator 21 is the input end of the desalination unit 2, and the fifth-effect evaporator 21 is the output end. The power steam source 1 is located at the input end of the first-effect evaporator 21 and provides high-pressure steam to it. The condenser 4 is located at the output end of the fifth-effect evaporator 21 and provides a negative pressure environment for the desalination unit 2, allowing steam to move sequentially from the first-effect evaporator 21 to the fifth-effect evaporator 21. The spray unit 3 sprays seawater into the interiors of the first to fifth evaporators 21.

[0033] Reference Figures 1-4 The evaporator 21 includes an evaporator shell 211, heat exchange tubes 212, a demister 213, a desalinated water collection mechanism 214, and a concentrated brine collection pipe 215. Multiple heat exchange tubes 212 are arrayed within the evaporator shell 211 and arranged along the axial direction of the evaporator shell 211. The demister 213 is located at the input end of the evaporator shell 211. The concentrated brine collection pipe 215 is located at the bottom of the evaporator 21 and is connected to the inner cavity of the evaporator shell 211. The desalinated water collection mechanism 214 includes a desalinated water collection tank 2141 and a desalinated water discharge pipe 2142. The desalinated water collection tank 2141 is fixedly installed on the heat exchange tube 212 near the output end of the evaporator shell 211, and the inner cavity of the desalinated water collection tank 2141 is connected to the heat exchange tube 212. One end of the desalinated water discharge pipe 2142 is connected to the bottom of the desalinated water collection tank 2141, and the other end is connected to a desalinated water header pipe 216. Multiple desalinated water discharge pipes 2142 are connected in parallel on the desalinated water header pipe 216. The side wall of the desalinated water collection tank 2141 is provided with multiple end plates 2143, and the end plates 2143 are made of transparent material.

[0034] Reference Figure 1 Below the first-effect evaporator 21 to the fifth-effect evaporator 21, there is a concentrated brine discharge pipe 217, and multiple concentrated brine collection pipes 215 are connected in parallel on the concentrated brine discharge pipe 217; a flash tank 218 is installed on the concentrated brine discharge pipe 217, and multiple flash tanks 218 are connected in series through the concentrated brine discharge pipe 217; a steam return pipe 2181 is installed on the flash tank 218, the steam return pipe 2181 extends into the inner cavity of the evaporator shell 211, and the outlet height of the steam return pipe 2181 is higher than the liquid level height inside the evaporator shell 211.

[0035] Reference Figure 1The spray unit 3 includes a seawater delivery pipe 31 and multiple spray pipes 32. The seawater delivery pipe 31 is located outside the first-effect evaporator 21 to the fifth-effect evaporator 21. The multiple spray pipes 32 are connected in parallel to the seawater delivery pipe 31. The discharge ends of the spray pipes 32 are respectively located in the inner cavities of the five evaporator shells 211, and the spray pipes 32 are located above the heat exchange tubes 212. The seawater delivery pipe 31 supplies seawater to the multiple spray pipes 32, and the seawater flows out from the spray pipes 32 and sprays onto the heat exchange tubes 212.

[0036] Reference Figure 2 The online conductivity monitor 5 includes a display controller 51, a transmission circuit, an alarm device 53, and multiple conductivity electrodes 52. The multiple conductivity electrodes 52 are respectively disposed on multiple desalinated water discharge pipes 2142. Each conductivity electrode 52 includes two parallel plates that extend into the inner cavity of the desalinated water discharge pipe 2142. One end of the transmission circuit is connected to the conductivity electrode 52, and the other end is connected to the display controller 51. The display controller 51 displays the resistivity of the desalinated water. The alarm device 53 is electrically connected to the display controller 51.

[0037] Reference Figure 1 The condenser 4 includes a high-pressure steam discharge pipe 41, a non-condensable steam discharge pipe 42, and a vacuum suction device 43. The vacuum suction device 43 is located outside the fifth-effect evaporator 21. One end of the high-pressure steam discharge pipe 41 is connected to the top of the heat exchange tube 212 inside the fifth-effect evaporator 21, and the other end is connected to the vacuum suction device 43. One end of the non-condensable steam discharge pipe 42 is connected to the top of the shell 211 of the fifth-effect evaporator, and the other end is connected to the vacuum suction device 43. A cooling water discharge pipe 219 is provided at the bottom of the fifth-effect evaporator 21, and the cooling water discharge pipe 219 is connected to the inner cavity of the evaporator shell 211.

[0038] The implementation principle of the seawater desalination device for easy leak location described in this application is as follows: During seawater desalination, a power steam source 1 first supplies high-pressure steam to the first-effect evaporator 21. The high-pressure steam passes through the demister 213 of the first-effect evaporator 21 and then enters the heat exchange tubes 212, where the temperature rises. Simultaneously, the seawater delivery pipe 31 sprays seawater through the spray pipe 32 onto the heat exchange tubes 212 from the first-effect evaporator 21 to the fifth-effect evaporator 21. When the seawater is sprayed onto the heat exchange tubes 212 inside the first-effect evaporator 21, a portion of the seawater is evaporated by the high-temperature heat exchange tubes 212 to form freshwater steam. The steam inside the heat exchange tubes 212 condenses to form desalinated water. The desalinated water collects in the desalinated water collection tank 2141 at the end of the heat exchange tubes 212 and is discharged from the desalinated water discharge pipe 2142 at the bottom of the collection tank 2141. Water vapor enters the heat exchange tubes 212 of the second-effect evaporator 21 after passing through the demister 213. The fresh water vapor raises the temperature of the heat exchange tubes 212. When seawater is sprayed onto the heat exchange tubes 212 of the second-effect evaporator 21, the fresh water vapor condenses into desalinated water, and the seawater evaporates to form new fresh water vapor. This principle continues until the fresh water vapor enters the fifth-effect evaporator 21. The fresh water vapor forms desalinated water in the heat exchange tubes 212 of the fifth-effect evaporator 21. The uncondensed fresh water vapor is discharged through the high-pressure steam discharge pipe 41 by the vacuum suction device 43. The fresh water vapor formed by the evaporation of seawater on the heat exchange tubes 212 in the fifth-effect evaporator 21 is discharged through the non-condensable steam discharge pipe 42 by the vacuum suction device 43. The unevaporated seawater in the fifth-effect evaporator 21 is discharged through the cooling water discharge pipe 219. The desalinated water produced by the first-effect evaporator 21 to the fifth-effect evaporator 21 flows into the desalinated water main pipe 216 through the desalinated water discharge pipe 2142. At the same time, the seawater that has not evaporated in the first-effect evaporator 21 to the fourth-effect evaporator 21 enters the flash tank 218 through the concentrated brine collection pipe 215. The high-temperature seawater boils and evaporates rapidly in the flash tank 218 and undergoes two-phase separation. The generated steam enters the evaporator shell 211 through the steam return pipe 2181 for further heat exchange and condensation.

[0039] During seawater desalination, the online conductivity monitor 5 monitors the resistivity of the desalinated water in the desalinated water discharge pipe 2142 in real time. By inserting two parallel plates into the desalinated water discharge pipe 2412, the parallel plates apply an electric potential and measure the current. The transmission circuit transmits the current data to the display controller 51. The display controller 51 calculates the conductivity based on the current data. When the conductivity exceeds the preset value, it can be determined that seawater is mixed in the desalinated water pipe. The display controller 51 transmits the signal to the alarm device 53 to trigger an alarm. The operator can determine that the heat exchange tube 212 is leaking based on the location of the online conductivity monitor 5 in the desalinated water discharge pipe 2142 where the alarm was generated. At the same time, the heat exchange tube 212 can be viewed through the transparent end plate 2143 to confirm the specific location of the leak. After opening the end plate 2143, the leaking heat exchange tube 212 can be replaced and repaired, realizing the rapid location of the leak and the quick replacement and repair of the leaking heat exchange tube 212, thereby reducing the loss of freshwater.

[0040] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. This application is not limited to the exact structures described above and illustrated in the accompanying drawings, and it should not be considered that the specific implementation of this application is limited to these descriptions. For those skilled in the art, various changes and modifications made without departing from the concept of this application should be considered to fall within the protection scope of this application.

Claims

1. A seawater desalination device that facilitates the location of leaks, characterized in that, include: The equipment includes a power steam source (1), a desalination unit (2), a spray unit (3), a condenser (4), and an online conductivity monitor (5). The power steam source (1) is located at the input end of the desalination unit (2) and is used to supply steam to the desalination unit (2). The condenser (4) is located at the output end of the desalination unit (2); the spray unit (3) is used to spray seawater into the desalination unit (2); The desalination unit (2) includes multiple evaporators (21), which are connected in series via connecting flanges; The evaporator (21) includes: an evaporator shell (211), heat exchange tubes (212), a demister (213), a desalinated water collection mechanism (214), and a concentrated brine collection pipe (215). Multiple heat exchange tubes (212) are arranged in an array inside the evaporator shell (211), and the heat exchange tubes (212) are arranged along the axial direction of the evaporator shell (211). The demister (213) is located at the input end of the evaporator shell (211). The spray unit (3) includes a seawater delivery pipe (31) and multiple spray pipes (32). The multiple spray pipes (32) are arranged in parallel on the seawater delivery pipe (31). The spray pipes (32) are respectively arranged in the inner cavity of multiple evaporator shells (211), and the spray pipes (32) are located above the heat exchange tubes (212). The spray pipes (32) are used to spray seawater onto the heat exchange tubes (212). The concentrated brine collection pipe (215) is located at the bottom of the evaporator (21), and the concentrated brine collection pipe (215) is connected to the inner cavity of the evaporator shell (211). The desalinated water collection mechanism (214) includes a desalinated water collection tank (2141) and a desalinated water discharge pipe (2142). The desalinated water collection tank (2141) is fixedly installed on the side of the heat exchange tube (212) near the output end of the evaporator shell (211), and the inner cavity of the desalinated water collection tank (2141) is connected to the heat exchange tube (212). One end of the desalinated water discharge pipe (2142) is connected to the bottom of the desalinated water collection tank (2141), and the other end is connected to a desalinated water main pipe (216). Multiple desalinated water discharge pipes (2142) are connected in parallel on the desalinated water main pipe (216). The online conductivity monitor (5) is installed on the desalinated water discharge pipe (2142), and the online conductivity monitor (5) is used to monitor the conductivity of the water flow in the desalinated water discharge pipe (2142) in real time.

2. The seawater desalination device for facilitating leak location as described in claim 1, characterized in that, The online conductivity monitor (5) includes a display controller (51), a transmission circuit, and multiple conductivity electrodes (52). The multiple conductivity electrodes (52) are respectively disposed on multiple desalinated water discharge pipes (2142). Each conductivity electrode (52) includes two parallel plates, and the two parallel plates extend into the inner cavity of the desalinated water discharge pipe (2142). One end of the transmission circuit is connected to the conductivity electrode (52), and the other end is connected to the display controller (51). The display controller (51) is used to display the resistivity of the desalinated water.

3. The seawater desalination device for facilitating leak location as described in claim 2, characterized in that, The online conductivity monitor (5) also includes an alarm device (53), which is electrically connected to the display controller (51).

4. The seawater desalination device for facilitating leak location as described in claim 1, characterized in that, It also includes a concentrated brine discharge pipe (217), and multiple concentrated brine collection pipes (215) are connected in parallel on the concentrated brine discharge pipe (217); a flash tank (218) is provided on the concentrated brine discharge pipe (217), and multiple flash tanks (218) are connected in series through the concentrated brine discharge pipe (217); The flash tank (218) is provided with a steam return pipe (2181), which extends into the inner cavity of the evaporator shell (211), and the outlet height of the steam return pipe (2181) is higher than the liquid level height inside the evaporator shell (211).

5. The seawater desalination device for facilitating leak location as described in claim 1, characterized in that, The condenser (4) is installed on the evaporator (21) at the output end of the desalination unit (2). The condenser (4) includes a high-pressure steam discharge pipe (41), a non-condensable steam discharge pipe (42), and a vacuum suction device (43). The vacuum suction device (43) is installed outside the evaporator (21). One end of the high-pressure steam discharge pipe (41) is connected to the top of the heat exchange tube (212), and the other end is connected to the vacuum suction device (43). One end of the non-condensable steam discharge pipe (42) is connected to the top of the evaporator shell (211), and the other end is connected to the vacuum suction device (43).

6. The seawater desalination device for facilitating leak location as described in claim 1, characterized in that, The bottom of the evaporator (21) at the output end of the desalination unit (2) is provided with a cooling water discharge pipe (219), which is connected to the inner cavity of the evaporator shell (211).

7. The seawater desalination device for facilitating leak location as described in claim 1, characterized in that, The desalinated water collection tank (2141) has multiple end plates (2143) on its side wall, and the end plates (2143) are made of transparent material.

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