A waste heat recovery device and method for soda ash diluted calcium solution

Abstract

The present invention discloses a waste heat recovery device and method for soda ash dilute calcium solution, comprising a negative pressure flash evaporation device, a vertical exhaust steam heat exchanger, a hot water circulation pump, a centrifugal heat pump, and a water vapor compressor. The vertical exhaust steam heat exchanger comprises a feed pipe, a liquid inlet pipe, a first liquid outlet pipe, a second liquid outlet pipe, a third liquid outlet pipe, and a discharge pipe. The discharge port of an exhaust steam demister is connected to the feed pipe of the vertical exhaust steam heat exchanger. The centrifugal heat pump comprises an evaporator, a condenser, and a steam-water separator. The discharge port of the condenser is connected to the feed port of the steam-water separator. The discharge pipe is connected to a condensate recovery tank via a pipeline. The condensate recovery tank is connected to a salt production condensate water tank via a condensate recovery pump. The present invention achieves efficient recovery and utilization of waste heat generated during the production of soda ash dilute calcium solution through the synergistic effect of components such as the negative pressure flash evaporation device, the vertical exhaust steam heat exchanger, the hot water circulation pump, the centrifugal heat pump, and the water vapor compressor, thereby significantly improving energy utilization efficiency.

Description

Technical Field

[0001] The present invention relates to the field of soda ash production technology and equipment, and in particular to a soda ash dilute calcium solution waste heat recovery device and method. Background Art

[0002] The treatment of dilute calcium solution is a critical step in the soda ash production process, often generating significant amounts of waste heat. If this waste heat isn't effectively utilized, it not only wastes significant energy but also increases production costs and the environmental burden. Therefore, efficiently recovering and utilizing this waste heat has become a pressing issue for soda ash manufacturers.

[0003] In traditional soda ash dilute calcium solution treatment processes, waste heat is often directly discharged or simply cooled. This approach not only fails to effectively utilize waste heat resources but also may cause secondary environmental pollution. With the continuous advancement of energy conservation and emission reduction policies and the increasing efficiency of energy utilization, soda ash manufacturers are beginning to seek more efficient and environmentally friendly waste heat recovery technologies.

[0004] In recent years, waste heat recovery technology has been widely used in various industrial fields and has achieved remarkable results. In the field of soda ash production, the introduction of advanced waste heat recovery equipment can effectively recover the waste heat generated during the treatment of dilute calcium solution and convert it into reusable heat energy or water resources, thereby achieving energy conservation, emission reduction, and lowering production costs.

[0005] Existing waste heat recovery systems for soda ash and diluted calcium solution mostly use heat exchangers and heat pumps. However, these devices still have certain shortcomings in terms of recovery efficiency and stability. For example, traditional heat exchangers are prone to scaling and clogging during the heat exchange process, affecting heat exchange efficiency. Heat pump systems also consume a certain amount of electricity during operation, increasing operating costs. Summary of the Invention

[0006] The purpose of the present invention is to solve the above technical problems, thereby providing a soda ash dilute calcium solution waste heat recovery device and method;

[0007] In order to solve the above technical problems, the present invention provides the following technical solutions:

[0008] One object of the present invention is to provide a waste heat recovery device for soda ash diluted calcium solution.

[0009] It includes a negative pressure flash evaporation device, a vertical exhaust steam heat exchanger, a hot water circulation pump, a centrifugal heat pump, and a water vapor compressor. An exhaust steam demister is provided between the negative pressure flash evaporation device and the vertical exhaust steam heat exchanger, and the discharge port of the negative pressure flash evaporation device is connected to the feed port of the exhaust steam demister;

[0010] The vertical exhaust steam heat exchanger includes a feed pipe, a liquid feed pipe, a first liquid discharge pipe, a second liquid discharge pipe, a third liquid discharge pipe, and a discharge pipe. The liquid feed pipe is used to introduce water. The discharge port of the exhaust steam demister is connected to the feed pipe of the vertical exhaust steam heat exchanger. The centrifugal heat pump includes an evaporator, a condenser, and a steam-water separator. The heated water is connected to the feed port of the evaporator through the first liquid discharge pipe. The discharge port of the evaporator is connected to the feed port of the condenser. The discharge port of the condenser is connected to the feed port of the steam-water separator. The water separator includes a first separation tube and a second separation tube. The first separation tube is connected to the water vapor compressor through a pipeline, and the second separation tube is connected to the desalted water pipe of the power workshop through a pipeline. The discharge port of the evaporator is also connected to the second liquid discharge pipe through a pipeline for secondary heating. The discharge pipe is connected to the condensate recovery tank through a pipeline. The third liquid discharge pipe is arranged on the lower end side wall of the vertical exhaust steam heat exchanger. The condensate recovery tank is connected to the salt making condensate water barrel through a condensate recovery pump. The first discharge pipe is connected to a constant pressure water replenishment device.

[0011] Optionally, the constant-pressure water replenishment device includes a water replenishment pipe, a water replenishment valve and a water replenishment pump, one end of the water replenishment pipe is connected to the first liquid outlet pipe, and the other end is connected to the desalted water pipe of the power workshop or an external water source, the water replenishment valve is arranged on the water replenishment pipe, and is used to control the water replenishment flow, and the water replenishment pump is arranged on the water replenishment pipe, and is used to provide water replenishment power. The constant-pressure water replenishment device also includes a pressure sensor and a controller, and the pressure sensor is arranged on the first liquid outlet pipe, and is used to monitor the pressure in the pipeline in real time, and the controller is connected to the pressure sensor and the water replenishment valve, and is used to control the opening and closing of the water replenishment valve according to the signal of the pressure sensor to keep the pressure in the pipeline stable.

[0012] Optionally, the vertical exhaust steam heat exchanger includes a heat exchange tube bundle and a shell, the heat exchange tube bundle is arranged in the shell, the heat exchange tube bundle is used to divide the inner cavity of the shell into a left cavity and a right cavity, the left cavity and the right cavity are both provided with a disturbance mechanism, the disturbance mechanism includes a motor, a screw, and a sliding block, the motor is arranged at the upper end of the shell, the upper end of the screw passes through the side wall of the shell and is connected to the output shaft of the motor, the sliding block is arranged on the screw, and the left and right side walls of the sliding block are inclinedly provided with several groups of disturbance plates, and the left and right side walls of the lower end of the sliding block are vertically provided with baffles, and the motor drives the screw to rotate, thereby driving the sliding block to slide up and down along the surface of the screw.

[0013] Optionally, the disruptor plates in the left cavity are inclined in opposite directions to those in the right cavity, with one set of tilt angles being upward and the other set of tilt angles being downward.

[0014] Optionally, the water vapor compressor is connected to a condensate recovery system for converting the compressed water vapor into liquid water and recovering it. The condensate recovery system includes a condensate collection tank and a condensate pump. The condensate collection tank is used to collect liquid water from the water vapor compressor, and the condensate pump is used to transport the condensate to a salt production system or other places where water is needed, thereby realizing the recycling of water resources.

[0015] Optionally, a temperature sensor and a pressure sensor are provided in the negative pressure flash evaporation device for real-time monitoring of the temperature and pressure during the flash evaporation process. The temperature sensor and the pressure sensor are connected to a control system, and the control system automatically adjusts the operating parameters of the negative pressure flash evaporation device according to the data fed back by the sensors to ensure that the flash evaporation process is carried out under optimal conditions and to improve the waste heat recovery efficiency.

[0016] Optionally, the condensate recovery tank also includes a liquid level sensor and a drain valve. The liquid level sensor is used to monitor the liquid level in the tank in real time. The drain valve is connected to the liquid level sensor and is used to automatically open or close according to the signal of the liquid level sensor to control the discharge of condensate.

[0017] Another object of the present invention is to provide a method for recovering waste heat from soda ash diluted calcium solution, comprising the following steps:

[0018] S1: The soda ash dilute calcium solution is passed into the negative pressure flash evaporation device for flash evaporation treatment. The temperature and pressure during the flash evaporation process are monitored in real time, and the operating parameters of the negative pressure flash evaporation device are automatically adjusted according to the monitoring data to ensure that the flash evaporation process is carried out under optimal conditions;

[0019] S2: After the flashed exhaust steam passes through the exhaust steam demister to remove foam, it is passed into the vertical exhaust steam heat exchanger for heat exchange. During the heat exchange process, the motor drives the screw to rotate, which in turn drives the sliding block to slide up and down along the screw surface, so that the disrupting plate disturbs the fluid in the heat exchanger, enhancing the heat exchange effect;

[0020] S3: The fluid after heat exchange is passed into the evaporator of the centrifugal heat pump for evaporation, the evaporated gas is passed into the condenser for condensation, and the condensed liquid is passed into the steam-water separator for steam-water separation;

[0021] S4: The water vapor after steam-water separation is passed into the water vapor compressor for compression, converted into liquid water and recovered to the condensate recovery system to achieve the recycling of water resources;

[0022] S5: Recover the remaining liquid after steam-water separation and the condensate at the lower end of the vertical exhaust steam heat exchanger into a condensate recovery tank. Monitor the liquid level in the tank in real time and automatically control the discharge of the condensate based on the liquid level signal.

[0023] S6: The pressure in the pipeline is monitored and controlled in real time through the constant pressure water supply device to maintain a stable pressure, so as to achieve continuous and stable operation of the entire waste heat recovery process.

[0024] Beneficial effects of the present invention

[0025] The present invention realizes the efficient recovery and utilization of waste heat generated in the production process of soda ash and dilute calcium solution through the synergistic effect of components such as a negative pressure flash evaporation device, a vertical exhaust steam heat exchanger, a hot water circulation pump, a centrifugal heat pump, and a water vapor compressor, significantly improving energy utilization efficiency and making important contributions to energy conservation, emission reduction, and sustainable development of enterprises.

[0026] A heat exchange tube bundle and a disturbance mechanism are set in the vertical exhaust steam heat exchanger. The sliding block slides up and down along the screw through the drive of the motor, driving the disturbance plate to disturb the fluid in the left and right cavities, thereby enhancing the turbulence of the fluid and improving the heat exchange efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a structural schematic diagram of the present invention.

[0028] Figure 2 This is an enlarged view of the structure of the vertical exhaust steam heat exchanger of the present invention.

[0029] Figure 3 This is a cross-sectional view of the structure of the vertical exhaust steam heat exchanger of the present invention.

[0030] Figure 4 This is an enlarged view of the structure of the constant pressure water replenishment device of the present invention.

[0031] Explanation of the accompanying drawings: 1-negative pressure flash evaporation device, 2-vertical exhaust steam heat exchanger, 3-hot water circulation pump, 4-centrifugal heat pump, 5-water vapor compressor, 6-exhaust steam demister, 7-feed pipe, 8-liquid inlet pipe, 9-first liquid outlet pipe, 10-second liquid outlet pipe, 11-third liquid outlet pipe, 12-discharge pipe, 13-constant pressure water supply device, 14-water supply pipeline, 15-water supply valve, 16-water supply pump, 17-heat exchange tube bundle, 18-shell, 19-left cavity, 20-right cavity, 21-motor, 22-screw, 23-sliding block, 24-disturbance plate, 25-baffle, 26-condensate collection tank, 27-condensate pump, 28-condensate recovery tank, 29-evaporator, 30-condenser, 31-steam-water separator, 32-first separation tube, 33-second separation tube. DETAILED DESCRIPTION

[0032] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0033] Example

[0034] like Figures 1-4 As shown, one object of the present invention is to provide a waste heat recovery device for soda ash diluted calcium solution,

[0035] It includes a negative pressure flash evaporation device 1, a vertical exhaust steam heat exchanger 2, a hot water circulation pump 3, a centrifugal heat pump 4, and a water vapor compressor 5. An exhaust steam demister 6 is provided between the negative pressure flash evaporation device 1 and the vertical exhaust steam heat exchanger 2. The discharge port of the negative pressure flash evaporation device 1 is connected to the feed port of the exhaust steam demister 6.

[0036] The vertical exhaust steam heat exchanger 2 includes a feed pipe 7, a liquid feed pipe 8, a first liquid discharge pipe 9, a second liquid discharge pipe 10, a third liquid discharge pipe 11, and a discharge pipe 12. The liquid feed pipe 8 is used to introduce water. The discharge port of the exhaust steam demister 6 is communicated with the feed pipe 7 of the vertical exhaust steam heat exchanger 2. The centrifugal heat pump 4 includes an evaporator 29, a condenser 30, and a steam-water separator 31. The heated water is connected to the feed port of the evaporator 29 through the first liquid discharge pipe 9. The discharge port of the evaporator 29 is connected to the feed port of the condenser 30. The discharge port of the condenser 30 is connected to the feed port of the steam-water separator 31. The steam-water separator 31 includes a first separation tube 32 and a second separation tube 33. The first separation tube 32 is connected to the water vapor compressor 5 through a pipeline, and the second separation tube 33 is connected to the desalted water pipe of the power workshop through a pipeline. The discharge port of the evaporator 29 is also connected to the second liquid discharge pipe 10 through a pipeline for secondary heating. The discharge pipe 12 is connected to the condensate recovery tank 28 through a pipeline. The third liquid discharge pipe 11 is arranged on the lower end side wall of the vertical exhaust steam heat exchanger 2. The condensate recovery tank 28 is connected to the salt making condensate bucket through a condensate recovery pump. The first discharge pipe 12 is connected to a constant pressure water replenishment device 13.

[0037] The main purpose of the above-mentioned configuration is to recover and utilize the waste heat generated during the production of soda ash and diluted calcium solution. To achieve this goal, the device adopts multiple components such as negative pressure flash evaporation, vertical exhaust steam heat exchanger 2, hot water circulation pump 3, centrifugal heat pump 4 and water vapor compressor 5, and effectively recovers and utilizes the waste heat through their synergistic effect.

[0038] Negative pressure flash evaporation:

[0039] During the negative pressure flash evaporation process, the soda ash and dilute calcium solution are flash evaporated under negative pressure conditions, so that part of the water evaporates rapidly in the form of steam. The heat released in this process is the main source of waste heat.

[0040] Exhaust steam demister 6:

[0041] The exhaust steam generated from the negative pressure flash evaporation process, i.e., the gas with a small amount of liquid and impurities in the steam, first enters the exhaust steam demister 6. The main function of the exhaust steam demister 6 is to remove foam and impurities in the exhaust steam to ensure the smooth progress of the subsequent heat exchange process and improve the heat exchange efficiency.

[0042] Vertical exhaust steam heat exchanger 2:

[0043] The exhaust steam after defoaming treatment enters the vertical exhaust steam heat exchanger 2, which adopts a multi-tube design, including a feed pipe 7, a liquid inlet pipe 8, a first liquid outlet pipe 9, a second liquid outlet pipe 10, a third liquid outlet pipe 11 and a discharge pipe 12. This design allows the water and exhaust steam to fully contact and exchange heat in the heat exchanger, thereby maximizing the recovery of heat energy in the exhaust steam. Specifically, the water enters the heat exchanger through the liquid inlet pipe 8, and after heat exchange with the exhaust steam, the heated water flows out through the first liquid outlet pipe 9 for subsequent heat energy utilization. At the same time, part of the heated water can also be reheated through the second liquid outlet pipe 10, further improving the heat energy recovery rate. Finally, the exhaust steam after heat exchange is discharged through the discharge pipe 12.

[0044] Centrifugal heat pump 4:

[0045] The heated water enters the evaporator 29 of the centrifugal heat pump 4, further absorbs heat and is converted into steam. Then, the steam enters the condenser 30, releases heat in the condenser 30 and is condensed into liquid water. In this process, the heat energy is further converted and recovered. The condensed water enters the steam-water separator 31, which separates the water and possible impurities through the separation effect. The separated water can be transported through pipelines to other places where it is needed for reuse.

[0046] Water vapor compressor 5:

[0047] The water vapor separated from the steam-water separator 31 enters the water vapor compressor 5 for compression. During the compression process, the water vapor is converted into liquid water, and the recycling of water resources is realized. The compressed liquid water can be transported to the salt making condensation water tank or other places where water is needed for reuse.

[0048] In summary, the soda ash diluted calcium solution waste heat recovery device achieves effective recovery and utilization of waste heat and improves the utilization rate of water resources through the synergistic effect of multiple components. It not only helps to save energy and reduce costs, but also helps to reduce environmental pollution and promote sustainable development.

[0049] The constant-pressure water replenishment device 13 includes a water replenishment pipe 14, a water replenishment valve 15 and a water replenishment pump 16. One end of the water replenishment pipe 14 is connected to the first liquid outlet pipe 9, and the other end is connected to the desalted water pipe of the power workshop or an external water source. The water replenishment valve 15 is arranged on the water replenishment pipe 14 to control the water replenishment flow rate. The water replenishment pump 16 is arranged on the water replenishment pipe 14 to provide water replenishment power. The constant-pressure water replenishment device 13 also includes a pressure sensor and a controller. The pressure sensor is arranged on the first liquid outlet pipe 9 to monitor the pressure in the pipeline in real time. The controller is connected to the pressure sensor and the water replenishment valve 15 to control the opening and closing of the water replenishment valve 15 according to the signal of the pressure sensor to keep the pressure in the pipeline stable.

[0050] In the soda ash diluted calcium solution waste heat recovery device, the constant pressure water supply device 13 ensures the pressure stability in the first liquid outlet pipe 9, thereby helping to improve the heat exchange efficiency and the stability of the entire system.

[0051] One end of the water replenishment pipe 14 is connected to the first liquid outlet pipe 9, and the other end is connected to the desalted water pipe of the power workshop or an external water source. This design allows the water replenishment process to flexibly select the water source, and water can be replenished from the desalted water of the power workshop or from an external water source.

[0052] The water supply valve 15 is provided on the water supply pipe 14. Its main function is to control the water supply flow. By adjusting the opening of the water supply valve 15, the amount of water supply entering the first liquid outlet pipe 9 can be accurately controlled, thereby ensuring the pressure stability in the pipe.

[0053] The water replenishment pump 16 is also provided on the water replenishment pipe 14, which provides the necessary power for the water replenishment process. When the system needs water replenishment, the water replenishment pump 16 will start and pump water from the water source into the first liquid outlet pipe 9 to replenish the water volume reduced due to the heat exchange process.

[0054] The pressure sensor is arranged on the first liquid outlet pipe 9. Its main task is to monitor the pressure changes in the pipeline in real time. The pressure sensor can sense tiny pressure fluctuations and convert them into electrical signals to transmit to the controller.

[0055] The controller is connected to the pressure sensor and the water supply valve 15. It determines whether the pressure in the pipeline is stable based on the signal transmitted by the pressure sensor. When the pressure in the pipeline is lower than the set value, the controller will issue an instruction to open the water supply valve 15 and start the water supply pump 16 to supply water; when the pressure in the pipeline reaches the set value, the controller will issue an instruction to close the water supply valve 15 and stop the water supply pump 16.

[0056] By ensuring stable pressure within the first liquid outlet pipe 9, the constant-pressure water replenishment device 13 facilitates a smoother and more efficient heat exchange process between the water and the exhaust steam, which helps improve heat recovery and reduce energy consumption. The constant-pressure water replenishment device 13 can monitor and automatically adjust the pressure within the pipeline in real time, making the entire system more stable and reliable. This helps reduce failures and downtime caused by pressure fluctuations and improves production efficiency. The introduction of pressure sensors and controllers enables real-time monitoring and automatic adjustment of the pressure within the pipeline, further increasing the system's automation level. This makes it easier for operators to monitor and manage the system, reducing labor intensity and the potential for human error.

[0057] In summary, the constant pressure water replenishment device 13 ensures the pressure stability in the first liquid outlet pipe 9, improves the heat exchange efficiency and system stability, and provides a strong guarantee for achieving a more efficient and reliable waste heat recovery process.

[0058] The vertical exhaust steam heat exchanger 2 includes a heat exchange tube bundle 17 and a shell 18. The heat exchange tube bundle 17 is arranged in the shell 18. The heat exchange tube bundle 17 is used to divide the inner cavity of the shell 18 into a left cavity 19 and a right cavity 20. The left cavity 19 and the right cavity 20 are both provided with a disrupting mechanism. The disrupting mechanism includes a motor 21, a screw 22, and a sliding block 23. The motor 21 is arranged at the upper end of the shell 18. The upper end of the screw 22 passes through the side wall of the shell 18 and is connected to the output shaft of the motor 21. The sliding block 23 is arranged on the screw 22. The left and right side walls of the sliding block 23 are both obliquely provided with several groups of disrupting plates 24. The left and right side walls of the lower end of the sliding block 23 are vertically provided with baffles 25. The motor 21 drives the screw 22 to rotate, thereby driving the sliding block 23 to slide up and down along the surface of the screw 22.

[0059] The heat exchange tube bundle 17 is the core part of the vertical exhaust steam heat exchanger 2 and is composed of multiple heat exchange tubes. These heat exchange tubes are made of high-efficiency heat-conducting materials to ensure that heat can be quickly transferred from the exhaust steam to the water liquid.

[0060] The motor 21 is the driving force source of the disturbance mechanism. The motor 21 drives the screw 22 to rotate, thereby driving the sliding block 23 and the disturbance plate 24 to move. The disturbance plate 24 is driven by the sliding block 23 to move between the heat exchange tube bundles 17, breaking the thermal boundary layer between the water liquid and the exhaust steam.

[0061] During the downward movement, the baffle 25 separates the liquid into two sides. When the baffle 25 divides the liquid into left and right sides, the flow path of the liquid is effectively dispersed, so that the disruptor plate 24 can more fully contact the liquid on the left and right sides during the up and down movement. This contact breaks the thermal boundary layer, so that heat can be transferred from the exhaust steam to the water liquid more quickly. The combination of diversion and disturbance makes the heat exchange process more uniform and efficient. The movement of the disruptor plate 24 continuously breaks the new thermal boundary layer, promotes the continuous transfer of heat, and thus improves the overall heat exchange effect.

[0062] The presence of the baffle 25 significantly changes the flow path of the liquid, forming a more complex flow field. This complex flow field reduces the fluid retention area, allowing the liquid to flow more smoothly through the heat exchange tube bundle 17, thereby improving the overall fluidity. The up and down movement of the disruptor plate 24 further promotes the mixing and flow of the liquid. It continuously pushes the liquid, reduces the dead water area, and allows the liquid to more fully contact the heat exchange tube bundle 17, thereby improving the heat exchange efficiency.

[0063] After the baffle 25 diverts the liquid, the flow path of the liquid becomes longer, which means that the contact area between the liquid and the heat exchange tube bundle 17 also increases accordingly. The longer flow path and more contact area allow more opportunities for heat to be transferred from the exhaust steam to the water liquid.

[0064] The movement of the disruptor plate 24 further increases the contact opportunity between the liquid and the heat exchange tube bundle 17. It continuously changes the flow direction of the liquid so that the liquid can more fully cover the surface of the heat exchange tube bundle 17, thereby improving the heat exchange area and heat exchange efficiency.

[0065] The inclined disruptor plate 24 can better adapt to the flow direction of the liquid. It contacts and exchanges heat with the liquid at a more optimized angle, which allows heat to be transferred more smoothly from the exhaust steam to the water liquid. The optimized heat exchange angle reduces the resistance in the heat exchange process, allowing the liquid to flow more easily through the heat exchange tube bundle 17, which helps to improve the heat exchange efficiency and reduce the energy consumption of the equipment.

[0066] The inclined disturbance plate 24 can produce a greater disturbance effect when moving up and down, breaking the thermal boundary layer in a more efficient way, so that heat can be transferred to the water more quickly. This enhanced disturbance effect not only improves the heat transfer efficiency, but also makes the heat transfer process more uniform and stable. It reduces local overheating or overcooling and improves the overall heat transfer performance.

[0067] The inclined disruptor plate 24 can better adapt to the flow direction of the liquid. This design makes the interaction between the disruptor plate 24 and the fluid more harmonious when moving, reducing the shaking caused by fluid impact. The optimized angle design helps to reduce the resistance encountered by the disruptor plate 24 during movement. When the resistance is reduced, the movement of the disruptor plate 24 is smoother, thereby reducing vibration.

[0068] The baffle 25 divides the liquid into two sides, which changes the flow path of the fluid. The disruptor plate 24 is set at an angle, which can better interact with the diverted fluid and further reduce the shaking caused by uneven fluid flow.

[0069] In summary, the synergistic effect of the disruptor plate 24 and the baffle 25 and the effect of the inclined setting of the disruptor plate 24 act together on the vertical exhaust steam heat exchanger 2, significantly improving the heat exchange efficiency, fluidity and equipment stability.

[0070] The disrupting plates 24 in the left cavity 19 and the disrupting plates 24 in the right cavity 20 are inclined in opposite directions, with one group inclined upward and the other group inclined downward.

[0071] When the disturbance plates 24 in the left cavity 19 and the right cavity 20 are tilted in opposite directions, their disturbance effects on the water liquid and the exhaust steam will also be opposite. This opposite disturbance effect makes the flow path of the fluid in the heat exchanger more complex and changeable. The complex flow pattern helps to break more thermal boundary layers, so that heat can be transferred to the water liquid more quickly and evenly.

[0072] The oppositely inclined disruptor plate 24 continuously pushes and mixes the water liquid and exhaust steam during movement. This mixing effect makes the temperature and composition of the fluid more uniform, further improving the heat exchange effect. At the same time, the mixing effect also helps to reduce the fluid retention area, allowing the fluid to more fully contact the heat exchange tube bundle 17.

[0073] The complex flow pattern increases the contact area between the water and the exhaust steam in the heat exchanger. More contact area means more heat transfer opportunities, thereby improving the heat exchange efficiency. At the same time, the oppositely inclined disruptor plates 24 also help guide the fluid to more areas of the heat exchange tube bundle 17, further expanding the heat exchange area.

[0074] The complex flow pattern and increased heat transfer area together increase the heat transfer rate. Heat can be transferred from the exhaust steam to the water liquid more quickly, thereby improving the overall performance of the heat exchanger. The increased heat transfer rate also helps to reduce the size and cost of the heat exchanger because the same heat transfer task can be completed in a shorter time.

[0075] The oppositely inclined disruptor plates 24 make the flow path of the fluid in the heat exchanger longer. The longer flow path means that the fluid stays longer in the heat exchanger. The extended residence time allows the fluid to more fully contact the heat exchange tube bundle 17, thereby improving the heat energy recovery rate.

[0076] In conventional heat exchangers, the fluid sometimes experiences a "short-circuiting" phenomenon, that is, the fluid flows directly through the heat exchanger without fully contacting the heat exchange tube bundle 17. In contrast, the inclined disruptor plate 24 design helps to reduce the occurrence of this short-circuiting phenomenon. They guide the fluid to more areas of the heat exchange tube bundle 17 and ensure that the fluid stays in the heat exchanger for a sufficient time to undergo sufficient heat exchange.

[0077] In summary, the design of the disruptor plates 24 in the left cavity 19 and the right cavity 20 with opposite inclination directions improves the overall performance of the vertical exhaust steam heat exchanger 2 by forming a complex flow pattern, enhancing the heat transfer effect and extending the residence time.

[0078] The water vapor compressor 5 is connected to a condensed water recovery system for converting the compressed water vapor into liquid water and recovering it. The condensed water recovery system includes a condensed water collection tank 26 and a condensed water pump 27. The condensed water collection tank 26 is used to collect liquid water from the water vapor compressor 5, and the condensed water pump 27 is used to transport the condensed water to the salt production system or other places where water is needed, thereby realizing the recycling of water resources.

[0079] The water vapor compressor 5 compresses the low-pressure, low-temperature water vapor from the flash tank or other steam equipment to increase its pressure and temperature. During the compression process, the energy in the water vapor is further utilized and converted into a high-pressure, high-temperature state, which provides favorable conditions for the subsequent condensation process.

[0080] The water vapor compressor 5 is connected to the flash tank or other steam equipment in the condensate recovery system through a pipeline. The low-temperature water vapor from these equipment is sent to the water vapor compressor 5 for compression. The compressed high-temperature, high-pressure water vapor then enters the condenser 30, where it exchanges heat with a cooling medium such as water or air, releases heat and condenses into liquid water. The heat released during the condensation process can be recovered and utilized to preheat other fluids entering the system or for other forms of thermal energy utilization.

[0081] Through the compression and condensation process of the water vapor compressor 5, low-temperature water vapor that might have been directly discharged or wasted is converted into valuable liquid water, thereby realizing the conservation and reuse of water resources. This treatment method not only reduces the waste of water resources, but also reduces the dependence on fresh water sources, helping to alleviate the problem of water shortage.

[0082] The condensed water collection tank 26 is used to receive liquid water flowing out of the condenser 30. After condensation treatment, most of the impurities and dissolved gases in the liquid water have been removed and the liquid water has a high degree of purity. The condensed water collection tank 26 usually has sufficient volume to cope with the system's instantaneous flow fluctuations and the need to store backup water.

[0083] The condensate pump 27 is responsible for transporting the liquid water in the condensate collection tank 26 to places where water is needed, such as salt production systems, boiler water supply systems or other industrial production processes. The condensate pump 27 usually has a high head and flow regulation capability to ensure that the condensate can be transported to the target location stably and efficiently.

[0084] By setting up the condensate collection tank 26 and the condensate pump 27, the recovered condensate can be conveniently transported to various places where water is needed. This recycling method not only reduces the consumption of fresh water, but also reduces the pollution to the environment caused by wastewater discharge.

[0085] In summary, the connection between the water vapor compressor 5 and the condensate recovery system, as well as the setting of the condensate collection tank 26 and the condensate pump 27, together constitute an efficient and environmentally friendly water resource recycling system. This system not only improves the utilization rate of water resources, but also helps to alleviate the problem of water shortage and reduce the risk of environmental pollution.

[0086] The negative pressure flash evaporation device 1 is provided with a temperature sensor and a pressure sensor for real-time monitoring of the temperature and pressure during the flash evaporation process. The temperature sensor and the pressure sensor are connected to a control system, and the control system automatically adjusts the operating parameters of the negative pressure flash evaporation device 1 according to the data fed back by the sensors to ensure that the flash evaporation process is carried out under optimal conditions and improve the waste heat recovery efficiency.

[0087] The temperature sensor is installed on the negative pressure flash evaporation device 1, which can capture and record the temperature data during the flash evaporation process in real time. This data is crucial for evaluating the flash evaporation effect, adjusting operating parameters, and preventing potential safety problems. High-precision temperature sensors, such as certain models of thermocouples, ensure the accuracy of temperature data, enabling the control system to make decisions based on reliable data.

[0088] By monitoring the temperature in real time, the control system can determine whether the current flash evaporation process is within the optimal temperature range. When the temperature deviates from the set range, the control system will automatically adjust relevant operating parameters such as heating power, cooling water flow, etc., so that the temperature quickly returns to the optimal range, thereby ensuring the stability and efficiency of the flash evaporation process.

[0089] The pressure sensor is used to monitor the operating pressure in the negative pressure flash evaporation device 1. During the negative pressure flash evaporation process, the operating pressure is one of the key factors affecting the flash evaporation effect. By monitoring the pressure data in real time, it can be ensured that the flash evaporation process is carried out under the set negative pressure environment.

[0090] The creation of a negative pressure environment usually relies on equipment such as a vacuum pump set, while the pressure sensor is responsible for real-time monitoring of whether the vacuum degree meets the requirements. When the pressure data is abnormal, such as insufficient or too high vacuum degree, the control system will promptly issue an alarm and take corresponding remedial measures.

[0091] According to the feedback data from the pressure sensor, the control system can automatically adjust the operating parameters of the vacuum pump group, such as the pumping rate, the operating time, etc., to ensure that the operating pressure in the negative pressure flash device 1 is always maintained within the optimal range.

[0092] In addition, the control system may also predict future operating conditions based on the changing trends of pressure data and adjust relevant parameters in advance to cope with potential fluctuations or failures.

[0093] The control system of the negative pressure flash evaporation device 1 is usually a highly integrated automation system that can simultaneously receive real-time data from temperature sensors and pressure sensors and perform comprehensive analysis and processing. The control system has built-in advanced algorithms and logic control programs, which can automatically adjust operating parameters according to preset process parameters and real-time data to ensure that the flash evaporation process is carried out under optimal conditions.

[0094] By precisely controlling the temperature and pressure parameters during the flash evaporation process, the control system can optimize waste heat recovery efficiency. When flash evaporation is carried out under negative pressure, the boiling point decreases due to the reduced operating pressure, making it easier for the light components in the material to be removed and converted into steam to carry away heat. By reasonably controlling the temperature and pressure parameters, it can be ensured that the heat carried in the steam is fully utilized and converted into useful energy forms such as hot water, steam, etc.

[0095] The automatic adjustment function enables the negative pressure flash evaporation device 1 to maintain a stable operating state in the face of various changes in working conditions. Whether it is fluctuations in the properties of the raw materials or interference from the external environment such as temperature changes, power grid fluctuations, etc., the control system can respond to these changes by automatically adjusting relevant parameters and ensure the continuity and stability of the flash evaporation process.

[0096] In summary, the temperature sensors and pressure sensors provided in the negative pressure flash evaporation device 1 and the corresponding control system together constitute an efficient and stable automatic monitoring system. This system ensures that the flash evaporation process is carried out under optimal conditions by real-time monitoring and automatic adjustment of key parameters, thereby improving the waste heat recovery efficiency and the overall performance of the system.

[0097] The condensate recovery tank 28 also includes a liquid level sensor and a drain valve. The liquid level sensor is used to monitor the liquid level in the tank in real time. The drain valve is connected to the liquid level sensor and is used to automatically open or close according to the signal of the liquid level sensor to control the discharge of the condensate.

[0098] The liquid level sensor is installed inside the condensate recovery tank 28 and can capture and record the liquid level data in the tank in real time. This data is crucial for assessing the accumulation of condensate, determining whether discharge is necessary, and preventing potential safety issues. High-precision liquid level sensors, such as certain models of ultrasonic level gauges, ensure the accuracy of liquid level data, allowing the control system to make decisions based on reliable data.

[0099] By monitoring the liquid level in real time, the control system can determine whether the liquid level in the condensate recovery tank 28 has reached a preset discharge threshold. Once the liquid level reaches or exceeds this threshold, the control system will trigger the opening of the drain valve to discharge the condensate in time. The timely discharge of condensate not only helps to recover valuable liquid resources, but also avoids a series of problems caused by excessively high liquid levels in the tank, such as overflow and equipment damage.

[0100] The drain valve is connected to the liquid level sensor through a control system. When the liquid level sensor detects that the liquid level in the tank reaches or exceeds the preset threshold, it will send a signal to the control system. After receiving this signal, the control system will immediately trigger the opening operation of the drain valve. The opening degree and time of the drain valve can be precisely controlled according to actual needs to ensure the smooth discharge of condensate.

[0101] Through the automatic control connection of the liquid level sensor and the drain valve, the condensate recovery system achieves a high degree of automation. This not only reduces the burden of manual monitoring and operation, but also improves the operating efficiency and stability of the system. Automated control can also reduce safety issues caused by human operational errors, such as overflow caused by forgetting to drain condensate.

[0102] Real-time monitoring of the liquid level sensor and automatic control of the drain valve together constitute an effective safety mechanism. When the liquid level in the tank rises abnormally, the system will trigger the drain operation in time to prevent condensate from overflowing out of the tank. Overflow accidents will not only lead to the waste of liquid resources, but may also cause environmental pollution and even cause serious consequences such as fire. Therefore, the automatic control of the liquid level sensor and drain valve is of great significance in preventing the occurrence of such safety accidents.

[0103] In addition to preventing overflow accidents, the automatic control of liquid level sensors and drain valves can also improve the overall safety of the condensate recovery system. Through real-time monitoring and precise control, the system can promptly detect and address various potential safety hazards. For example, when the liquid level sensor detects an abnormally low liquid level in the tank, the system can determine that there may be a leak problem and promptly issue an alarm or take other remedial measures.

[0104] In summary, the connection between the liquid level sensor and the drain valve in the condensate recovery tank 28 realizes the automatic control of condensate discharge. This mechanism not only improves the automation and stability of the system, but also helps prevent safety accidents such as overflow of the condensate recovery tank 28 due to excessive liquid level. This is of great significance for ensuring the safe and efficient operation of the condensate recovery system.

[0105] The present application realizes the efficient recovery and utilization of waste heat generated in the production process of soda ash dilute calcium solution through the synergistic effect of components such as the negative pressure flash evaporation device 1, the vertical exhaust steam heat exchanger 2, the hot water circulation pump 3, the centrifugal heat pump 4 and the water vapor compressor 5. The negative pressure flash evaporation device 1 serves as the front end of the entire system. It partially vaporizes the high-temperature dilute calcium solution by reducing the pressure, thereby releasing a large amount of heat energy. The exhaust steam generated in this process, i.e., low-pressure steam, is rich in heat energy and is an important source of waste heat recovery. Subsequently, the exhaust steam enters the vertical exhaust steam heat exchanger 2 and exchanges heat with the cold water entering the heat exchanger. In this process, the heat energy of the exhaust steam is transferred to the cold water, causing it to heat up, thereby realizing the initial recovery of heat energy. The hot water circulation pump 3 is responsible for circulating the hot water after heat exchange back to the production system or for use in other links that require hot water, further improving the utilization rate of thermal energy. The centrifugal heat pump 4 further heats the hot water after heat exchange through the coordinated work of the evaporator 29 and the condenser 30, so that it achieves a higher thermal energy utilization value. At the same time, the steam-water separator 31 of the heat pump ensures the stable operation of the system and avoids damage to the equipment by water vapor. Finally, the water vapor compressor 5 compresses the excess water vapor generated in the system, converts it into liquid water and recycles it. This process not only realizes the recycling of water resources, but also further recovers the heat energy in the water vapor, thereby improving the energy utilization efficiency of the entire system.

[0106] The present invention realizes the efficient recovery and utilization of waste heat generated in the production process of soda ash and dilute calcium solution through the synergistic effect of components such as the negative pressure flash evaporation device 1, the vertical exhaust steam heat exchanger 2, the hot water circulation pump 3, the centrifugal heat pump 4 and the water vapor compressor 5, thereby significantly improving energy utilization efficiency and making important contributions to energy conservation, emission reduction and sustainable development of enterprises.

[0107] This application is equipped with a variety of monitoring equipment such as pressure sensors, temperature sensors, liquid level sensors, etc., and connected to the control system, realizing real-time monitoring and automatic adjustment of key links such as flash evaporation process, water replenishment process, condensate recovery process, etc., ensuring that the device operates under optimal conditions and further improving the waste heat recovery efficiency.

[0108] A heat exchange tube bundle 17 and a disturbance mechanism are provided in the vertical exhaust steam heat exchanger 2. Driven by a motor 21, the sliding block 23 slides up and down along the screw 22, driving the disturbance plate 24 to disturb the fluid in the left cavity 19 and the right cavity 20, thereby enhancing the turbulence of the fluid and improving the heat exchange efficiency.

[0109] The water vapor compressor 5 in the device is connected to the condensed water recovery system to convert the compressed water vapor into liquid water and recycle it, thereby realizing the recycling of water resources and reducing the waste of water resources.

[0110] The constant pressure water supply device 13 is set to monitor the pressure in the pipeline in real time through a pressure sensor, and control the opening and closing of the water supply valve 15 according to the pressure signal, thereby maintaining the pressure in the pipeline stable and ensuring the stable operation of the device.

[0111] The waste heat recovery device described in this application is not only suitable for the production process of soda ash and dilute calcium solution, but can also be promoted and applied to other industrial fields that require waste heat recovery. It has broad application prospects and important economic value.

[0112] Another object of the present invention is to provide a method for recovering waste heat from soda ash diluted calcium solution, comprising the following steps:

[0113] S1: passing the soda ash weak calcium solution into the negative pressure flash evaporation device 1 for flash evaporation treatment, monitoring the temperature and pressure during the flash evaporation process in real time, and automatically adjusting the operating parameters of the negative pressure flash evaporation device 1 according to the monitoring data to ensure that the flash evaporation process is carried out under optimal conditions;

[0114] S2: After the flashed exhaust steam passes through the exhaust steam demister 6 to remove foam, it is passed into the vertical exhaust steam heat exchanger 2 for heat exchange. During the heat exchange process, the motor 21 drives the screw 22 to rotate, which in turn drives the sliding block 23 to slide up and down along the surface of the screw 22, so that the disrupting plate 24 disturbs the fluid in the heat exchanger, thereby enhancing the heat exchange effect;

[0115] S3: The fluid after heat exchange is passed into the evaporator 29 of the centrifugal heat pump 4 for evaporation, and the evaporated gas is passed into the condenser 30 for condensation, and the condensed liquid is then passed into the steam-water separator 31 for steam-water separation;

[0116] S4: The steam after steam-water separation is passed into the steam compressor 5 for compression, converted into liquid water and recovered to the condensate recovery system, thereby realizing the recycling of water resources;

[0117] S5: Recover the remaining liquid after steam-water separation and the condensate at the lower end of the vertical exhaust steam heat exchanger 2 into the condensate recovery tank 28, monitor the liquid level in the tank in real time, and automatically control the discharge of the condensate based on the liquid level signal;

[0118] S6: The pressure in the pipeline is monitored and controlled in real time by the constant pressure water supply device 13 to keep the pressure stable, so as to achieve continuous and stable operation of the entire waste heat recovery process.

[0119] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A waste heat recovery device for soda ash diluted calcium solution, characterized in that: It includes a negative pressure flash evaporation device, a vertical exhaust steam heat exchanger, a hot water circulation pump, a centrifugal heat pump, and a water vapor compressor. An exhaust steam demister is provided between the negative pressure flash evaporation device and the vertical exhaust steam heat exchanger, and the discharge port of the negative pressure flash evaporation device is connected to the feed port of the exhaust steam demister; The vertical exhaust steam heat exchanger includes a feed pipe, a liquid feed pipe, a first liquid discharge pipe, a second liquid discharge pipe, a third liquid discharge pipe, and a discharge pipe. The liquid feed pipe is used to introduce water. The discharge port of the exhaust steam demister is connected to the feed pipe of the vertical exhaust steam heat exchanger. The centrifugal heat pump includes an evaporator, a condenser, and a steam-water separator. The heated water is connected to the feed port of the evaporator through the first liquid discharge pipe. The discharge port of the evaporator is connected to the feed port of the condenser. The discharge port of the condenser is connected to the feed port of the steam-water separator. The water separator includes a first separation tube and a second separation tube, the first separation tube is connected to the water vapor compressor through a pipeline, the second separation tube is connected to the desalted water pipe of the power workshop through a pipeline, the discharge port of the evaporator is also connected to the second liquid outlet pipe through a pipeline for secondary heating, the discharge pipe is connected to the condensate recovery tank through a pipeline, the third liquid outlet pipe is arranged on the lower end side wall of the vertical exhaust steam heat exchanger, the condensate recovery tank is connected to the salt making condensate bucket through a condensate recovery pump, and the first liquid outlet pipe is connected to a constant pressure water replenishment device; The vertical exhaust steam heat exchanger includes a heat exchange tube bundle and a shell. The heat exchange tube bundle is arranged in the shell. The heat exchange tube bundle is used to divide the inner cavity of the shell into a left cavity and a right cavity. The left cavity and the right cavity are both provided with a disrupting mechanism. The disrupting mechanism includes a motor, a screw, and a sliding block. The motor is arranged at the upper end of the shell. The upper end of the screw passes through the side wall of the shell and is connected to the output shaft of the motor. The sliding block is arranged on the screw. The left and right side walls of the sliding block are both obliquely provided with a plurality of groups of disrupting plates. The left and right side walls of the lower end of the sliding block are vertically provided with baffles. The motor drives the screw to rotate, thereby driving the sliding block to slide up and down along the surface of the screw. The disrupting plates in the left cavity are inclined in opposite directions to those in the right cavity, with one group of plates being inclined upward and the other group being inclined downward.

2. A soda ash diluted calcium solution waste heat recovery device according to claim 1, characterized in that: The constant-pressure water replenishment device includes a water replenishment pipe, a water replenishment valve and a water replenishment pump. One end of the water replenishment pipe is connected to the first liquid outlet pipe, and the other end is connected to the desalted water pipe of the power workshop or an external water source. The water replenishment valve is arranged on the water replenishment pipe to control the water replenishment flow rate. The water replenishment pump is arranged on the water replenishment pipe to provide water replenishment power. The constant-pressure water replenishment device also includes a pressure sensor and a controller. The pressure sensor is arranged on the first liquid outlet pipe to monitor the pressure in the pipeline in real time. The controller is connected to the pressure sensor and the water replenishment valve, and is used to control the opening and closing of the water replenishment valve according to the signal of the pressure sensor to keep the pressure in the pipeline stable.

3. A soda ash dilute calcium solution waste heat recovery device according to claim 1, characterized in that: The water vapor compressor is connected to a condensate recovery system for converting the compressed water vapor into liquid water and recovering it. The condensate recovery system includes a condensate collection tank and a condensate pump. The condensate collection tank is used to collect liquid water from the water vapor compressor, and the condensate pump is used to transport the condensate to the salt production system to achieve the recycling of water resources.

4. A soda ash dilute calcium solution waste heat recovery device according to claim 1, characterized in that: The negative pressure flash evaporation device is provided with a temperature sensor and a pressure sensor for real-time monitoring of the temperature and pressure during the flash evaporation process. The temperature sensor and the pressure sensor are connected to a control system, and the control system automatically adjusts the operating parameters of the negative pressure flash evaporation device according to the data fed back by the sensors to ensure that the flash evaporation process is carried out under optimal conditions and improve the waste heat recovery efficiency.

5. A soda ash dilute calcium solution waste heat recovery device according to claim 1, characterized in that: The condensate recovery tank also includes a liquid level sensor and a drain valve. The liquid level sensor is used to monitor the liquid level in the tank in real time. The drain valve is connected to the liquid level sensor and is used to automatically open or close according to the signal of the liquid level sensor to control the discharge of condensate.

6. A waste heat recovery method for a waste heat recovery device for soda ash diluted calcium solution according to any one of claims 1 to 5, characterized in that: The following steps are involved: S1: The soda ash dilute calcium solution is passed into the negative pressure flash evaporation device for flash evaporation treatment. The temperature and pressure during the flash evaporation process are monitored in real time, and the operating parameters of the negative pressure flash evaporation device are automatically adjusted according to the monitoring data to ensure that the flash evaporation process is carried out under optimal conditions; S2: After the flashed exhaust steam passes through the exhaust steam demister to remove foam, it is passed into the vertical exhaust steam heat exchanger for heat exchange. During the heat exchange process, the motor drives the screw to rotate, which in turn drives the sliding block to slide up and down along the screw surface, so that the disrupting plate disturbs the fluid in the heat exchanger, enhancing the heat exchange effect; S3: The fluid after heat exchange is passed into the evaporator of the centrifugal heat pump for evaporation, the evaporated gas is passed into the condenser for condensation, and the condensed liquid is passed into the steam-water separator for steam-water separation; S4: The water vapor after steam-water separation is passed into the water vapor compressor for compression, converted into liquid water and recovered to the condensate recovery system to achieve the recycling of water resources; S5: Recover the remaining liquid after steam-water separation and the condensate at the lower end of the vertical exhaust steam heat exchanger into a condensate recovery tank. Monitor the liquid level in the tank in real time and automatically control the discharge of the condensate based on the liquid level signal. S6: The pressure in the pipeline is monitored and controlled in real time through the constant pressure water supply device to maintain a stable pressure, so as to achieve continuous and stable operation of the entire waste heat recovery process.

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