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CN-121993272-A - Power generation system and method

CN121993272ACN 121993272 ACN121993272 ACN 121993272ACN-121993272-A

Abstract

The invention discloses a power generation system and a method, and relates to the technical field of thermal energy power generation, wherein the power generation system comprises a generator, a first circulation module and a second circulation module, the first circulation module is used for guiding working medium to flow, the first circulation module comprises an evaporator, an expansion device, a condenser and a working medium pump which are sequentially connected, the expansion device is connected with the generator to generate electric energy, the working medium pump is used for increasing the pressure of condensed working medium and conveying the working medium to the evaporator, the second circulation module comprises a thermochemical battery and a cooling tower, the downstream of the cooling tower is provided with a circulation pump, the thermochemical battery is provided with a hot end heat exchanger connected with an inlet of the working medium and a cold end heat exchanger positioned at the downstream of the circulation pump, and the downstream of the cold end heat exchanger is communicated with the cooling tower. The technical scheme provided by the invention can solve the problems that when the traditional organic Rankine cycle is used for generating electricity, the heat energy utilization rate of waste heat is low, and the overall generating efficiency is influenced.

Inventors

  • ZHANG WENYAO
  • FANG CHAOHE
  • CHEN BINGBING
  • WANG SHEJIAO
  • ZHU DONGXUE
  • LI YUEXIN

Assignees

  • 中石油深圳新能源研究院有限公司
  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241105

Claims (10)

  1. 1. A power generation system, comprising: A generator (1); The first circulation module (2), the first circulation module (2) is used for guiding the working medium to flow, the first circulation module (2) comprises an evaporator (21), an expansion device (22), a condenser (23) and a working medium pump (24) which are connected in sequence; the evaporator (21) is used for evaporating a working medium; The expansion device (22) is used for expanding the evaporated working medium, and the expansion device (22) is connected with the generator (1) to generate electric energy; The condenser (23) is used for condensing the expanded working medium; The working medium pump (24) for increasing the pressure of the condensed working medium and delivering the working medium to the evaporator (21), and The second circulation module (3), second circulation module (3) include thermochemical battery (31) and cooling tower (32), and the low reaches of cooling tower (32) still are equipped with circulating pump (33), thermochemical battery (31) have hot end heat exchanger (311) and being located of connecting working medium entry (4) cold end heat exchanger (312) of circulating pump (33) low reaches, the low reaches intercommunication of cold end heat exchanger (312) cooling tower (32).
  2. 2. The power generation system according to claim 1, wherein the medium inlet (4) is located between the evaporator (21) and the hot side heat exchanger (311), a first valve (101) is arranged between the medium inlet (4) and the hot side heat exchanger (311), a second valve (102) is arranged between the medium inlet (4) and the evaporator (21), the medium inlet (4) is provided with a temperature sensor (5), and the temperature sensor (5) is electrically connected with the first valve (101) and the second valve (102).
  3. 3. The power generation system according to claim 2, characterized in that the evaporator (21) connects a branch between the first valve (101) and the hot side heat exchanger (311).
  4. 4. A power generation system according to claim 3, wherein the first circulation module (2) further comprises a regenerator (25), one end of the regenerator (25) being located between the expansion device (22) and the condenser (23), the other end of the regenerator (25) being located between the condenser (23) and the evaporator (21).
  5. 5. The power generation system according to claim 4, characterized in that the first circulation module (2) further comprises a preheater (26), the preheater (26) connecting the regenerator (25) with the evaporator (21).
  6. 6. The power generation system according to claim 5, characterized in that the outlet of the hot side heat exchanger (311) is connected to the preheater (26), and a branch between the hot side heat exchanger (311) and the preheater (26) is connected to the outlet of the preheater (26).
  7. 7. The power generation system according to claim 6, characterized in that a third valve (103) is arranged between the hot side heat exchanger (311) and the preheater (26), a fourth valve (104) is arranged in a branch between the hot side heat exchanger (311) and the preheater (26), and the temperature sensor (5) is electrically connected with the third valve (103) and the fourth valve (104).
  8. 8. The power generation system according to any one of claims 1 to 7, wherein the condenser (23) is connected to the circulation pump (33), and an outlet of the condenser (23) is connected to an inlet of the cooling tower (32).
  9. 9. The power generation system according to claim 8, wherein a fifth valve (105) is provided between the circulation pump (33) and the cold-end heat exchanger (312), a sixth valve (106) is provided between the circulation pump (33) and the condenser (23), and the temperature sensor (5) is electrically connected to the fifth valve (105) and the sixth valve (106).
  10. 10. A power generation method implemented using the power generation system according to any one of claims 2 to 9, comprising the steps of: Introducing a working medium into the first circulation module (2) and the second circulation module (3); Determining a threshold value for the working medium temperature at the medium inlet (4) when the net generated power or thermal efficiency of the first circulation module (2) and the second circulation module (3) are equal; when the working medium temperature of the medium inlet (4) is smaller than the threshold value, the second valve (102) is closed, the first valve (101) is opened, and the working medium enters the second circulation module (3) through the first valve (101) to generate electricity; When the working medium temperature of the medium inlet (4) is greater than the threshold value, the first valve (101) and the second valve (102) are opened, and the working medium enters the first circulation module (2) and the second circulation module (3) to generate power; When the working medium temperature of the medium inlet (4) is larger than the threshold value, the opening degree of the first valve (101) and the opening degree of the second valve (102) are adjusted to enable the net power generation power or the thermal efficiency of the first circulation module (2) and the net power generation power or the thermal efficiency of the second circulation module (3) to be equal, and the threshold value is updated.

Description

Power generation system and method Technical Field The invention relates to the technical field of thermal energy power generation, in particular to a power generation system and a power generation method. Background Renewable clean energy sources such as geothermal energy, solar heat energy, biomass energy and ocean temperature difference energy are efficiently developed and utilized, industrial waste heat resources are recycled in a cascade mode, the problem of energy crisis is solved, carbon emission in an industrial production process is reduced, and the global climate target is assisted. In the field of low-temperature heat energy utilization, the prior art has thousands of years such as organic Rankine cycle, kalina cycle, flash cycle, transcritical cycle and the like. Among them, the organic Rankine cycle is attracting attention with the unique advantage of being able to efficiently convert lower temperature heat energy (usually not less than 100 ℃), the thermochemical battery is an emerging thermoelectric conversion technology, and the thermochemical battery directly converts low-grade heat energy into electric energy by utilizing the thermal diffusion effect of redox ion pairs in solution and electrode reaction, thus providing a new idea for the efficient utilization of medium-low temperature heat energy. Because of the common adoption of aqueous solution, the technology can safely and effectively utilize low-temperature heat energy below 85 ℃ and widen the temperature range of available heat energy. In the traditional power generation system, the organic Rankine cycle has a certain potential in low-temperature heat energy utilization, but the utilization degree of the organic Rankine cycle on a heat source is still insufficient, and especially the heat transfer fluid after heat exchange of an evaporator still often contains considerable waste heat, so that the heat energy utilization rate of the waste heat is low, and the overall power generation efficiency is influenced. Disclosure of Invention The invention mainly aims to provide a power generation system and a method, and aims to solve the problems that when the traditional organic Rankine cycle is used for power generation, the utilization rate of heat energy of waste heat is low, and the overall power generation efficiency is affected. The power generation system comprises a generator, a first circulation module and a second circulation module, wherein the first circulation module is used for guiding working medium to flow, the first circulation module comprises an evaporator, an expansion device, a condenser and a working medium pump, the evaporator is used for evaporating the working medium, the expansion device is used for expanding the evaporated working medium, the expansion device is connected with the generator to generate electric energy, the condenser is used for condensing the expanded working medium, the working medium pump is used for increasing the pressure of the condensed working medium and conveying the working medium to the evaporator, the second circulation module comprises a thermochemical battery and a cooling tower, the circulation pump is further arranged at the downstream of the cooling tower, the thermochemical battery is provided with a hot end heat exchanger connected with a working medium inlet and a cold end heat exchanger positioned at the downstream of the circulation pump, and the downstream of the cold end heat exchanger is communicated with the cooling tower. In an embodiment, the medium inlet is located between the evaporator and the hot side heat exchanger, a first valve is arranged between the medium inlet and the hot side heat exchanger, a second valve is arranged between the medium inlet and the evaporator, and a temperature sensor is arranged at the medium inlet and is electrically connected with the first valve and the second valve. In one embodiment, the evaporator connects a branch between the first valve and the hot side heat exchanger. In an embodiment, the first circulation module further comprises a regenerator, one end of the regenerator being located between the expansion device and the condenser, and the other end of the regenerator being located between the condenser and the evaporator. In an embodiment, the first circulation module further comprises a preheater connecting the regenerator with the evaporator. In an embodiment, the outlet of the hot side heat exchanger is connected to the preheater, and a branch between the hot side heat exchanger and the preheater is connected to the outlet of the preheater. In an embodiment, a third valve is arranged between the hot end heat exchanger and the preheater, a fourth valve is arranged in a branch circuit between the hot end heat exchanger and the preheater, and the temperature sensor is electrically connected with the third valve and the fourth valve. In one embodiment, the condenser is connected to the circulation pump, and the outlet of the cond