CN-121173003-B - Gas-liquid interconversion compressed carbon dioxide energy storage system and utilization method of compression heat of system

CN121173003BCN 121173003 BCN121173003 BCN 121173003BCN-121173003-B

Abstract

The invention provides a gas-liquid interconversion compressed carbon dioxide energy storage system and a utilization method of compression heat of the system, and relates to the field of compressed carbon dioxide energy storage. The gas-liquid interconversion compression carbon dioxide energy storage system comprises a power generation module, wherein the power generation module comprises a carbon dioxide pipeline, a first condenser, a high-pressure liquid storage device, a first evaporator, a turbine unit, a second condenser, a low-pressure liquid storage device, a second evaporator and a compressor unit which are sequentially arranged. The compressed high-pressure gaseous carbon dioxide is condensed into liquid state by the first condenser and stored in the high-pressure liquid storage device, and the liquid carbon dioxide is heated into gas state by the first evaporator and then is sent into the turbine unit for power generation. The second condenser condenses the carbon dioxide after doing work into liquid, and the second evaporator heats the liquid carbon dioxide of the low-pressure liquid storage device into gas. Compared with gaseous storage, the liquid storage mode can obviously reduce the storage space and the occupied area of the system, reduce the construction cost and facilitate flexible deployment.

Inventors

ZHANG XIAOHAI
CHU PAN
Meng Zishuo
YANG WEI
Liao Lengrui

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: 20260505
Application Date: 20251120

Claims (7)

1. A gas-liquid interconversion compressed carbon dioxide energy storage system, comprising: the power generation module comprises a carbon dioxide pipeline, and a first condenser, a high-pressure liquid storage device, a first evaporator, a turbine unit, a second condenser, a low-pressure liquid storage device, a second evaporator and a compressor unit which are sequentially arranged in the carbon dioxide pipeline, wherein the first condenser is used for receiving high-pressure gaseous carbon dioxide compressed by the compressor unit, condensing the high-pressure gaseous carbon dioxide into liquid carbon dioxide and conveying the liquid carbon dioxide to the high-pressure liquid storage device for storage; the second condenser is used for condensing the carbon dioxide after acting by the turbine set into liquid carbon dioxide, and the second evaporator is used for heating the liquid carbon dioxide output by the low-pressure liquid storage device into gaseous carbon dioxide; A carbon dioxide pipeline between the turbine unit and the second condenser is provided with a supplementary interface; a carbon dioxide pipeline between the second evaporator and the compressor unit is provided with a supplementary interface; the gas-liquid interconversion compressed carbon dioxide energy storage system further comprises a carbon dioxide trapping device, wherein the carbon dioxide trapping device is communicated with the supplementing interface and an external carbon dioxide emission source; a first delivery pump is arranged between the second condenser and the low-pressure liquid storage device, and a second delivery pump is arranged between the low-pressure liquid storage device and the second evaporator.
2. The gas-liquid interconversion compressed carbon dioxide energy storage system of claim 1, wherein the cold source of the first condenser uses a first ethylene process waste cold as a cold source, and the cold source of the second condenser uses a second ethylene process waste cold as a cold source.
3. The gas-liquid interconversion compressed carbon dioxide energy storage system of claim 1, wherein the heat source of the first evaporator employs a first ethylene process waste heat as the heat source and the heat source of the second evaporator employs a second ethylene process waste heat as the heat source.
4. The gas-liquid interconversion compressed carbon dioxide energy storage system of claim 1, further comprising an energy storage module, a heat sink, and a heat release device; the energy storage module comprises an energy storage pipeline, and a low-temperature storage tank and a high-temperature storage tank which are arranged in the energy storage pipeline; The heat absorber is arranged on a carbon dioxide pipeline between the compressor unit and the first condenser, so that a low-temperature medium in the low-temperature storage tank is introduced through the energy storage pipeline and exchanges heat with carbon dioxide compressed by the compressor unit in the carbon dioxide pipeline; The heat release device is arranged on a carbon dioxide pipeline between the first evaporator and the turbine unit, so that a high-temperature medium in the high-temperature storage tank is introduced through the energy storage pipeline and exchanges heat with carbon dioxide to be introduced into the turbine unit in the carbon dioxide pipeline.
5. The gas-liquid interconversion compressed carbon dioxide energy storage system of claim 4, wherein the medium in the energy storage pipeline is pressurized water or heat transfer oil.
6. The gas-liquid interconversion compressed carbon dioxide energy storage system of claim 4, further comprising a heat supply branch and a heat supply storage tank, wherein one end of the heat supply branch is connected to the energy storage line between the heat absorber and the high temperature storage tank, the other end is connected to the inlet of the heat supply storage tank, and the outlet of the heat supply storage tank is connected to an external heat user.
7. A method for utilizing system compression heat, which is characterized in that the method for utilizing system compression heat comprises an energy storage step and an energy release step based on the gas-liquid mutual conversion compression carbon dioxide energy storage system of claim 4; The energy storage step comprises the steps of compressing gaseous carbon dioxide output by the second evaporator into high-pressure gaseous carbon dioxide by the compressor unit, conducting the energy storage pipeline, enabling a low-temperature medium in the low-temperature storage tank to flow into the heat absorber, enabling the low-temperature medium and the high-pressure gaseous carbon dioxide to exchange heat in the heat absorber to absorb heat, enabling the low-temperature medium after heat absorption to rise in temperature to form a high-temperature medium and be conveyed to the high-temperature storage tank to be stored, enabling the high-pressure gaseous carbon dioxide after heat absorption to release heat to flow into the first condenser, enabling the high-pressure gaseous carbon dioxide after heat absorption to flow into the first condenser to be condensed into liquid carbon dioxide, and conveying the liquid carbon dioxide to the high-pressure storage device to be stored; The energy release step comprises the steps that liquid carbon dioxide in the high-pressure liquid storage device flows into the first evaporator and is heated into gaseous carbon dioxide by the first evaporator, the energy storage pipeline is conducted, a high-temperature medium in the high-temperature storage tank flows into the heat release device, the high-temperature medium and the gaseous carbon dioxide exchange heat in the heat release device to release heat, the released high-temperature medium is cooled to form a low-temperature medium and flows back to the low-temperature storage tank, and the absorbed gaseous carbon dioxide is introduced into the turbine unit to drive the turbine unit to generate electricity.

Description

Gas-liquid interconversion compressed carbon dioxide energy storage system and utilization method of compression heat of system Technical Field The invention belongs to the technical field of compressed carbon dioxide energy storage, and particularly relates to a gas-liquid interconversion compressed carbon dioxide energy storage system and a utilization method of compression heat of the system. Background Renewable energy grid connection influences grid stability due to intermittent and fluctuation, and measures need to be taken for coping. Carbon dioxide energy storage technology is a research hotspot because of environmental protection, safety, fluctuation relief, high energy density and low environmental risk. However, in the prior art system, there are still some problems to be solved. For example, the gas tanks in the system for storing low pressure gaseous carbon dioxide result in a very large space required for the overall construction. This not only increases the floor space of the project, but also increases the costs of construction and maintenance, thereby limiting further popularization and application of the technology. Disclosure of Invention In view of the above, the present invention provides a gas-liquid interconversion compressed carbon dioxide energy storage system and a method for utilizing the compression heat of the system, which aims to reduce the construction space of the gas-liquid interconversion compressed carbon dioxide energy storage system. The technical scheme of the invention is realized as follows: The embodiment of the invention provides a gas-liquid interconversion compressed carbon dioxide energy storage system, which comprises a power generation module, wherein the power generation module comprises a carbon dioxide pipeline, a first condenser, a high-pressure liquid storage device, a first evaporator, a turbine set, a second condenser, a low-pressure liquid storage device, a second evaporator and a compressor set, wherein the first condenser, the high-pressure liquid storage device, the first evaporator, the second evaporator and the compressor set are sequentially arranged in the carbon dioxide pipeline, the first condenser is used for receiving high-pressure gaseous carbon dioxide compressed by the compressor set, condensing the high-pressure gaseous carbon dioxide into liquid carbon dioxide and delivering the liquid carbon dioxide to the high-pressure liquid storage device for storage, the first evaporator is used for receiving the liquid carbon dioxide output by the high-pressure liquid storage device, heating the liquid carbon dioxide into the gaseous carbon dioxide and then introducing the gaseous carbon dioxide into the turbine set for power generation, and the second condenser is used for condensing the liquid carbon dioxide output by the low-pressure liquid storage device into the gaseous carbon dioxide. In an embodiment, the cold source of the first condenser adopts the first ethylene process residual cold as the cold source, and the cold source of the second condenser adopts the second ethylene process residual cold as the cold source. In one embodiment, the heat source of the first evaporator uses the first ethylene process waste heat as the heat source, and the heat source of the second evaporator uses the second ethylene process waste heat as the heat source. In one embodiment, the carbon dioxide line between the turbine unit and the second condenser is provided with a supplemental interface, and/or the carbon dioxide line between the second evaporator and the compressor unit is provided with a supplemental interface. In one embodiment, the system further comprises a carbon dioxide capture device in communication with the carbon dioxide emission source outside the replenishment mouthpiece. In one embodiment, a first transfer pump is disposed between the second condenser and the low pressure reservoir, and/or a second transfer pump is disposed between the low pressure reservoir and the second evaporator. In one embodiment, the heat-exchange system further comprises an energy storage module, a heat absorber and a heat release device, wherein the energy storage module comprises an energy storage pipeline, a low-temperature storage tank and a high-temperature storage tank which are arranged in the energy storage pipeline, the heat absorber is arranged on a carbon dioxide pipeline between the compressor unit and the first condenser, so that a low-temperature medium in the low-temperature storage tank is introduced through the energy storage pipeline and exchanges heat with carbon dioxide compressed by the compressor unit in the carbon dioxide pipeline, and the heat release device is arranged on a carbon dioxide pipeline between the first evaporator and the turbine unit, so that a high-temperature medium in the high-temperature storage tank is introduced through the energy storage pipeline and exchanges heat with carbon dioxide to be introduced into the turbine