Waste heat power generation system combining high-pressure liquid heating medium with ORC (organic Rankine cycle)

Abstract

The utility model provides a waste heat power generation system combining a high-pressure liquid heating medium with an ORC. The waste heat power generation system comprises a flash evaporation device, a gas condensation type differential pressure generator set, an ORC generator set, an aftercooler and a condensate tank. Circulating cooling water is connected with the condensation type differential pressure generator set, the ORC generator set and the aftercooler through a circulating cooling water supply pipeline; high-pressure condensed water enters a flash evaporation device through a high-pressure condensed water pipeline, the top and the bottom of the flash evaporation device are connected with the gas condensation type differential pressure generator set and the ORC generator set respectively, the gas condensation type differential pressure generator set is connected with a low-temperature hot water discharging pipeline, the ORC generator set is connected with an after-cooler, and the after-cooler is connected with the flash evaporation device. The aftercooler is connected with a condensate tank, and the condensate tank is connected with an ORC unit hot water discharge pipeline. The device has the advantages that the energy recovery rate of high-pressure condensate water is remarkably increased, meanwhile, continuous and safe production in the industrial process is guaranteed through redundancy design, and economical efficiency and operation reliability are both achieved.

Description

Technical Field

[0001] This utility model relates to the field of industrial energy conservation and waste heat power generation technology, and in particular to a waste heat power generation system combining high-pressure liquid heat medium with ORC. Background Technology

[0002] Industrial processes often generate large amounts of high-pressure condensate, which typically carries significant heat energy (temperatures reaching 100-150℃). However, due to limitations in traditional process design, this heat transfer medium is often not effectively utilized in existing processes and must ultimately be cooled using equipment such as cooling towers. This approach not only results in direct waste of heat energy but also increases the load on the cooling system, leading to reduced energy efficiency and increased operating costs. This waste of low-grade heat energy is particularly pronounced in energy-intensive industries such as chemical, steel, and papermaking, negatively impacting both energy efficiency and economic performance. Utility Model Content

[0003] The purpose of this invention is to provide a waste heat power generation system combining high-pressure liquid heat medium with ORC, thereby solving the aforementioned problems existing in the prior art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows:

[0005] A waste heat power generation system combining high-pressure liquid heat transfer medium and ORC includes a flash evaporator, a condensing differential pressure generator set, an ORC generator set, an aftercooler, and a condensate tank. Circulating cooling water is connected to the condensing differential pressure generator set, the ORC generator set, and the aftercooler via a circulating cooling water supply pipeline. High-pressure condensate enters the flash evaporator via a high-pressure condensate pipeline. The top and bottom of the flash evaporator are connected to the condensing differential pressure generator set and the ORC generator set, respectively. A low-temperature hot water discharge pipeline is connected to the condensing differential pressure generator set. The ORC generator set is connected to the aftercooler, and the aftercooler is connected to the condensate tank. A hot water discharge pipeline from the ORC unit is connected to the condensate tank.

[0006] Preferably, the system further includes a steam standby cooler; the top of the flash evaporator is connected to the steam standby cooler; the steam standby cooler is connected to the condensing differential pressure generator set; the low-temperature hot water discharge pipeline is connected to the steam standby cooler; and a cooling water return pipeline is connected to the steam standby cooler.

[0007] Preferably, the system further includes a flash condensate backup cooler; the bottom of the flash evaporation device is connected to the flash condensate backup cooler; the flash condensate backup cooler is connected to the ORC generator set; the flash condensate backup cooler is connected to the connecting pipeline between the ORC generator set and the aftercooler; the flash condensate backup cooler is connected to the connecting pipeline between the condensing differential pressure generator set and the steam backup cooler.

[0008] Preferably, the flash evaporation device includes a main flash tank and a backup flash tank. The tops of both the main flash tank and the backup flash tank are connected to the condensing differential pressure generator set and the steam standby cooler. The bottoms of both the main flash tank and the backup flash tank are connected to the ORC generator set and the flash condensate standby cooler.

[0009] Preferably, a circulating water pump is installed on the circulating cooling water supply pipeline.

[0010] Preferably, a steam condensate pump is installed on the low-temperature hot water discharge pipeline.

[0011] Preferably, the hot water discharge pipeline of the ORC unit is equipped with a condensate pump.

[0012] Preferably, both the main flash tank and the backup flash tank are provided with flash steam vents at their tops.

[0013] The beneficial effects of this invention are: 1. Energy cascade utilization: By synergistically combining flash (steam)-pressure differential power generation and ORC (liquid) power generation, the thermal energy recovery of high-pressure condensate is maximized. 2. Operational reliability: The design of main and backup flash tanks and independent cooling circuits ensures that the process cooling requirements can still be stably met when the power generation system is shut down. 3. System flexibility: Pressure differential power generation and ORC power generation can operate independently or in parallel, adapting to fluctuations in heat transfer parameters under different operating conditions. 4. Process compatibility: The final output low-temperature condensate (around 45℃) can be directly reused or safely discharged, avoiding thermal shock to downstream systems. Attached Figure Description

[0014] Figure 1 This is a structural diagram of the waste heat power generation system in an embodiment of this utility model.

[0015] In the diagram: 1-Circulating cooling water supply pipeline; 2-Flash steam reserved outlet; 3-Steam standby cooler; 4-Condensing differential pressure generator set; 5-ORC generator set; 6-Circulating water pump; 7-Main flash tank; 8-Standby flash tank; 9-Flash condensate standby cooler; 10-Aftercooler; 11-Condensate tank; 12-Condensate pump; 13-Low temperature hot water discharge pipeline; 14-High pressure condensate input pipeline; 15-ORC unit hot water discharge pipeline; 16-Steam condensate pump; 17-Cooling water return pipeline. Detailed Implementation

[0016] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the scope of the present utility model.

[0017] In this embodiment, addressing the common pain points in industrial energy utilization in existing technologies, a waste heat power generation system synergistically combining high-pressure liquid heat transfer medium and Organic Rankine Cycle (ORC) is proposed. Through a three-stage energy recovery architecture of flash evaporation-pressure differential-ORC, the system achieves cascaded utilization of heat transfer medium energy. The system employs a main and backup dual flash tank design. After entering the system, the high-pressure condensate first undergoes depressurization flash evaporation in the flash evaporator. The generated saturated steam drives the condensing differential pressure generator set 4 to generate electricity. The low-pressure saturated water after flash evaporation then enters the ORC generator set 5 for secondary energy extraction.

[0018] To ensure continuous and stable operation of the process, the system is equipped with a backup flash tank and an emergency cooling circuit. When the condensing differential pressure generator set 4 or the ORC generator set 5 is shut down due to maintenance or failure, the backup flash tank can be put into use immediately. The heat medium is cooled to the temperature required by the process through the steam backup cooler 3, the flash condensate backup cooler 9 and the aftercooler 10, and then transported to the user's designated location by the condensate pump.

[0019] like Figure 1 As shown, the system specifically includes a flash evaporator, a condensing differential pressure generator set 4, an ORC generator set 5, an aftercooler 10, and a condensate tank 11. Circulating cooling water is connected to the condensing differential pressure generator set 4, the ORC generator set 5, and the aftercooler 10 via a circulating cooling water supply pipeline 1. High-pressure condensate enters the flash evaporator via a high-pressure condensate inlet pipeline 14. The top and bottom of the flash evaporator are connected to the condensing differential pressure generator set 4 and the ORC generator set 5, respectively. A low-temperature hot water discharge pipeline 13 is connected to the condensing differential pressure generator set 4. The ORC generator set 5 is connected to the aftercooler 10, and the aftercooler 10 is connected to the condensate tank 11. A hot water discharge pipeline 15 for the ORC generator set is connected to the condensate tank 11. A circulating water pump 6 is installed on the circulating cooling water supply pipeline 1. A steam condensate pump 16 is installed on the low-temperature hot water discharge pipeline 13 of the condensing differential pressure generator set, and a condensate pump 12 is installed on the hot water discharge pipeline 15 of the ORC generator set. The specific number of circulating water pump 6, steam condensate pump 16, and condensate pump 12 can be set according to actual conditions, such as... Figure 1 As shown, each type of pump is configured with one pump in use and one on standby.

[0020] In this embodiment, the system further includes a steam standby cooler 3 and a flash condensate standby cooler 9; the top of the flash evaporation device is connected to the steam standby cooler 3; the steam standby cooler 3 is connected to the condensing differential pressure generator set 4; the low-temperature hot water discharge pipeline 13 is connected to the steam standby cooler 3; a cooling water return pipeline 17 is connected to the steam standby cooler 3. The bottom of the flash evaporation device is connected to the flash condensate standby cooler 9; the flash condensate standby cooler 9 is connected to the ORC generator set 5; the flash condensate standby cooler 9 is connected to the connecting pipeline between the ORC generator set 5 and the aftercooler 10; the flash condensate standby cooler 9 is connected to the connecting pipeline between the condensing differential pressure generator set 4 and the steam standby cooler 3.

[0021] In this embodiment, the flash evaporation device includes a main flash tank 7 and a backup flash tank 8. The tops of both the main flash tank 7 and the backup flash tank 8 are connected to the condensing differential pressure generator set 4 and the steam standby cooler 3; the bottoms of both the main flash tank 7 and the backup flash tank 8 are connected to the ORC generator set 5 and the flash condensate standby cooler 9. The tops of both the main flash tank 7 and the backup flash tank 8 are provided with flash steam reserved outlets 2.

[0022] The system operates as follows: During normal operation, high-pressure condensate enters the main flash tank 7 and the backup flash tank 8 via the high-pressure condensate inlet pipeline 14 for depressurized flash evaporation. The high-pressure saturated steam generated during flash evaporation is discharged from the top of the tanks and enters the condensing differential pressure generator set 4 via pipelines to generate electricity. The condensate from the generated steam is then discharged to the location designated by the owner via the steam condensate pump 16. Simultaneously, the low-pressure saturated water at the bottom of the main flash tank 7 and the backup flash tank 8 enters the ORC generator set 5 via pipelines. After heat recovery, it is cooled to the required process temperature by the aftercooler 10 and finally flows into the condensate tank 11 via pipelines, and is then discharged to the location designated by the owner by the condensate pump 12.

[0023] The high-pressure saturated steam discharged from the top of the main flash tank 7 and the backup flash tank 8 enters the condensing differential pressure generator set 4 and also enters the steam standby cooler 3. The low-pressure hot water discharged from the bottom of the main flash tank 7 and the backup flash tank 8 enters the ORC generator set 5 and also enters the flash condensate standby cooler 9, thus ensuring the safe operation of the unit.

[0024] The circulating cooling water enters the circulating water pump 6 through the circulating cooling water supply pipeline 1 to supply circulating water to the condensing differential pressure generator set 4, the ORC generator set 5, the standby steam cooler, the flash condensate standby cooler 9, and the aftercooler 10. Finally, it is discharged to the location designated by the owner through the cooling water return pipeline 17.

[0025] The system has intelligent control function: regulating valves are installed on the corresponding connecting pipelines. When the heat medium parameters fluctuate and the ORC outlet temperature is too high, the regulating valve opens to divert part of the heat medium to the flash condensate standby cooler 9 for secondary cooling, ensuring that the output condensate temperature is stable at about 45℃. When the heat medium temperature is too low, the regulating valve opens to allow part of the heat medium to bypass directly to the condensate tank 11, maintaining the system thermal balance.

[0026] When ORC generator set 5 is under maintenance, the heat transfer medium is treated by flash condensate standby cooler 9; when condensing differential pressure generator set 4 is under maintenance, all heat transfer medium is treated by steam standby cooler 3. When condensing differential pressure generator set 4 and ORC generator set 5 are shut down at the same time, the system automatically switches to standby cooler operation. After being rapidly cooled by the standby cooler, the heat transfer medium is directly delivered to the location designated by the owner via condensate pump.

[0027] The system achieves cascaded utilization of thermal energy through three-stage energy recovery (flash evaporation-differential pressure-ORC), while employing a modular redundant architecture to ensure process continuity, combining high energy efficiency and operational reliability. The system can automatically switch operating modes according to the heat medium parameters and maintain the output condensate temperature stable within the technical requirement range of 45±2℃.

[0028] This system breaks away from the reliance of traditional ORC power generation systems on gaseous heat sources, and is optimized for the characteristics of high-pressure liquid heat transfer media. Secondly, it achieves flexible coupling between the generator set and the production process through dynamic regulating valves, ensuring no impact on the stability of the main process. Finally, its modular design allows the system to flexibly adapt to heat transfer media recovery requirements at different pressure levels. Actual engineering cases show that this solution can recover approximately 65%-75% of the waste heat transfer media energy, with an investment payback period of less than 3 years, while reducing the cooling system load by up to 40%, achieving a dual improvement in economic benefits and energy conservation and emission reduction.

[0029] By adopting the above-disclosed technical solution of this utility model, the following beneficial effects are obtained:

[0030] This invention provides a waste heat power generation system combining high-pressure liquid heat transfer medium and ORC (oral refrigerant flow), achieving cascaded energy utilization: through the synergy of flash evaporation (steam)-pressure differential power generation and ORC (liquid) power generation, the recovery of heat energy from high-pressure condensate is maximized. Operational reliability: The design of main and backup flash tanks and independent cooling circuits ensures stable performance to meet process cooling requirements even when the power generation system is shut down. System flexibility: Pressure differential power generation and ORC power generation can operate independently or in parallel, adapting to fluctuations in heat transfer medium parameters under different operating conditions. Process compatibility: The final output low-temperature condensate (around 45°C) can be directly reused or safely discharged, avoiding thermal shock to downstream systems.

[0031] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A waste heat power generation system combined with ORC by high pressure liquid heat medium, characterized in that: The system further comprises a steam backup cooler; the top of the flash device is connected with the steam backup cooler; the steam backup cooler is connected with the condensing pressure difference generator set; the low-temperature hot water discharge pipeline is connected with the steam backup cooler; the steam backup cooler is connected with a cooling water return pipeline.

2. The system for power generation from waste heat by high pressure liquid heat medium combined with ORC according to claim 1, characterized in that: The system further comprises a flash condensate backup cooler; the bottom of the flash device is connected with the flash condensate backup cooler; the flash condensate backup cooler is connected with the ORC generator set; the flash condensate backup cooler is connected on the connecting pipeline between the ORC generator set and the aftercooler; the flash condensate backup cooler is connected on the connecting pipeline between the condensing pressure difference generator set and the steam backup cooler.

3. The system for power generation from waste heat by high pressure liquid heat medium combined with ORC according to claim 2, characterized in that: The flash device comprises a main flash tank and a backup flash tank; the top of the main flash tank and the backup flash tank is connected with the condensing pressure difference generator set and the steam backup cooler; the bottom of the main flash tank and the backup flash tank is connected with the ORC generator set and the flash condensate backup cooler.

4. The system according to claim 3, wherein: A circulating water pump is arranged on the circulating cooling water supply pipeline.

5. The system for power generation from waste heat by high pressure liquid heat medium coupled with ORC as claimed in claim 1, wherein: A steam condensate pump is arranged on the low-temperature hot water discharge pipeline.

6. The system as claimed in claim 1, wherein the system further comprises a high pressure liquid heat medium ORC based waste heat power generation system. The ORC unit hot water discharge pipeline is provided with a condensate pump.

7. The system as claimed in claim 1, wherein the system further comprises a high pressure liquid heat medium ORC based waste heat power generation system. The top of the main flash tank and the backup flash tank is provided with a flash steam reservation flange.

8. The system as claimed in claim 4, wherein the system further comprises a high pressure liquid heat medium ORC based waste heat power generation system. ​

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