CN-117537253-B - Working medium filling and recycling assembly and method of carbon dioxide energy storage system

CN117537253BCN 117537253 BCN117537253 BCN 117537253BCN-117537253-B

Abstract

The working medium filling and recycling assembly comprises a liquid storage unit, a pressure balancing unit and a gas phase balancing branch pipe, wherein the liquid storage unit is used for storing liquid carbon dioxide and gaseous carbon dioxide, the liquid storage unit is used for receiving the liquid carbon dioxide input by a carbon dioxide tank car through a liquid phase interface or outputting the liquid carbon dioxide to the carbon dioxide tank car, the pressure balancing unit comprises a pressure regulating device and the gas phase balancing branch pipe, the pressure regulating device is used for carrying out gas-liquid conversion on the carbon dioxide so that the pressure in the liquid storage unit reaches the design pressure, the first end of the gas phase balancing branch pipe is connected with a first gas phase interface, the second end of the gas phase balancing branch pipe is used for connecting the carbon dioxide tank car, and the gaseous carbon dioxide can flow between the liquid storage unit and the carbon dioxide tank car through the gas phase balancing branch pipe so as to balance the pressure between the liquid storage unit and the carbon dioxide tank car. The embodiment of the invention can realize the rapid filling and recycling of the liquid carbon dioxide, save the construction period and reduce the project construction cost.

Inventors

Wen Shuaishuai
He Leiluo
SHAN LING
CHEN QIANG

Assignees

百穰新能源科技(深圳)有限公司

Dates

Publication Date: 20260508
Application Date: 20231208

Claims (8)

1. The utility model provides a carbon dioxide gas-liquid phase is filling recovery unit of energy storage system's working medium which characterized in that includes: the liquid storage unit is used for receiving the liquid carbon dioxide filled from the carbon dioxide tank car in a filling stage through the liquid phase interface or outputting the liquid carbon dioxide to the carbon dioxide tank car in a recycling stage through the liquid phase interface; The pressure balancing unit comprises a pressure regulating device and a gas phase balancing branch pipe, wherein the pressure regulating device is respectively connected with the liquid phase interface and the first gas phase interface, the pressure regulating device is used for carrying out gas-liquid conversion on carbon dioxide in the filling stage so as to enable the pressure in the liquid storage unit to reach the design pressure, the first end of the gas phase balancing branch pipe is connected with the first gas phase interface, the second end of the gas phase balancing branch pipe is used for being connected with the carbon dioxide tank car, and the gaseous carbon dioxide can flow between the liquid storage unit and the carbon dioxide tank car through the gas phase balancing branch pipe so as to balance the pressure between the liquid storage unit and the carbon dioxide tank car; the design pressure is the energy storage pressure of the carbon dioxide gas-liquid phase energy storage system; the pressure regulating device comprises a liquefying part and a gasifying part, wherein a working medium outlet of the liquefying part is connected with the liquid phase interface, a working medium side of the liquefying part is connected with the first gas phase interface, the liquefying part is used for converting gaseous carbon dioxide into liquid carbon dioxide and outputting the liquid carbon dioxide to the liquid storage unit when the transportation pressure of the carbon dioxide tank car is larger than the design pressure in the filling stage, so that the pressure in the liquid storage unit is reduced to the design pressure in the filling stage, a working medium inlet of the gasifying part is connected with the liquid phase interface, a working medium outlet of the gasifying part is connected with the first gas phase interface, and the gasifying part is used for converting the liquid carbon dioxide output by the liquid storage unit into gaseous carbon dioxide and outputting the gaseous carbon dioxide to the liquid storage unit when the transportation pressure of the carbon dioxide tank car is smaller than the design pressure in the filling stage, so that the pressure in the liquid storage unit is increased to the design pressure in the filling stage.
2. The carbon dioxide gas-liquid phase-change energy storage system working medium filling and recycling assembly according to claim 1, wherein the pressure balancing unit further comprises a first balancing pipe connected between the first gas phase interface and the liquefying part; the first end of the gas phase balance branch pipe is connected to the first balance pipe; Or the first end of the gas phase balance branch pipe is connected with the working medium inlet of the liquefying part.
3. The working fluid charging and recovering assembly of a carbon dioxide gas-liquid phase-change energy storage system according to claim 1, wherein said pressure balancing unit further comprises a second balancing pipe connected between a working fluid outlet of said gasification portion and said first gas interface, said first end of said gas-phase balancing branch pipe being connected to said second balancing pipe.
4. The working medium charging and recovering assembly of a carbon dioxide gas-liquid phase-change energy storage system according to claim 1, further comprising a heat exchange assembly, wherein the heat exchange assembly is used for heating the liquid carbon dioxide output by the carbon dioxide tank car to liquid carbon dioxide with a preset charging temperature in the charging stage and outputting the liquid carbon dioxide to the liquid storage unit.
5. The working medium filling and recycling assembly of the carbon dioxide gas-liquid phase-change energy storage system according to claim 1, further comprising a first transmission pipeline, a conveying pump and a second transmission pipeline, wherein the opposite ends of the first transmission pipeline are respectively connected with the liquid storage unit and the carbon dioxide tank car; And the second transmission pipeline is connected with the delivery pump in parallel, and a bypass control valve is arranged on the second transmission pipeline.
6. The working medium charging and recovering assembly of a carbon dioxide gas-liquid phase-change energy storage system according to claim 5, wherein the conveying pump is a two-way pump, the conveying pump is used for conveying the liquid carbon dioxide output by the carbon dioxide tank car to the liquid storage unit through the first conveying pipeline in the charging stage, and conveying the liquid carbon dioxide in the liquid storage unit to the carbon dioxide tank car through the first conveying pipeline in the recovering stage in a second direction, and the first direction is opposite to the second direction.
7. The working medium filling and recovering assembly of the carbon dioxide gas-liquid phase-change energy storage system according to any one of claims 1-6, further comprising a carbon dioxide tank car, wherein the carbon dioxide tank car is used for providing liquid carbon dioxide for the liquid storage unit in the filling stage or receiving and storing the liquid carbon dioxide output by the liquid storage unit in the recovering stage, a second gas phase interface is arranged at the top of the carbon dioxide tank car, and the second end of the gas phase balance branch pipe is connected to the second gas phase interface.
8. A method for recovering a working medium of a carbon dioxide gas-liquid phase-change energy storage system, which is characterized in that the method comprises the following steps of: the carbon dioxide tank car is communicated with the gas phase balance branch pipe, and the pressure between the carbon dioxide tank car and the liquid storage unit is balanced through the gas phase balance branch pipe; Communicating the carbon dioxide tank car with the liquid phase interface; The carbon dioxide tank truck outputs the liquid carbon dioxide to the liquid storage unit in a filling stage, or the liquid storage unit outputs the liquid carbon dioxide to the carbon dioxide tank truck in a recycling stage; In the filling stage, the pressure regulating device carries out gas-liquid conversion on carbon dioxide to enable the pressure in the liquid storage unit to reach the design pressure, specifically, when the transportation pressure of the carbon dioxide tank car is greater than or equal to the design pressure, the liquefying part converts the gaseous carbon dioxide into the liquid carbon dioxide and outputs the liquid carbon dioxide to the liquid storage unit so as to reduce the pressure in the liquid storage unit to the design pressure, and when the transportation pressure of the carbon dioxide tank car is smaller than the design pressure, the gasifying part converts the liquid carbon dioxide output by the liquid storage unit into gaseous carbon dioxide and outputs the gaseous carbon dioxide to the liquid storage unit so as to enable the pressure in the liquid storage unit to be increased to the design pressure.

Description

Working medium filling and recycling assembly and method of carbon dioxide energy storage system Technical Field The invention relates to the technical field of energy storage, in particular to a working medium filling and recycling assembly of a carbon dioxide energy storage system and a working medium filling and recycling method of the carbon dioxide energy storage system. Background Carbon dioxide energy storage is a novel physical energy storage technology, and the carbon dioxide energy storage system realizes energy storage based on carbon dioxide gas-liquid phase change, and the main working medium is carbon dioxide. The existing carbon dioxide energy storage system generally comprises an air storage, an energy storage component, a liquid storage tank and an energy release component which are sequentially connected in a closed loop mode. Wherein, the gas storage is provided with the accommodation cavity that is used for holding gaseous carbon dioxide. The energy storage assembly, the liquid storage tank and the energy release assembly can be collectively referred to as a working medium operation system. When the carbon dioxide energy storage system operates, carbon dioxide is converted between a gas state and a liquid state between the gas storage and the working medium operation system. The liquid carbon dioxide flowing out of the liquid storage tank is converted into gas through the energy release assembly and flows into the gas storage tank to release the energy stored in the energy storage process. Before the carbon dioxide energy storage system is in test operation, carbon dioxide working medium is filled into the carbon dioxide energy storage system, air in the system is replaced by high-purity carbon dioxide, the existing working medium filling mode is a gaseous filling mode, the carbon dioxide is gasified into gaseous carbon dioxide and then is filled into the system, the filling speed is low, project construction production period of the carbon dioxide energy storage system is seriously affected, and how to quickly fill the carbon dioxide working medium into the carbon dioxide energy storage system is an important problem for ensuring the operation of the carbon dioxide energy storage system. Disclosure of Invention Therefore, in order to solve the problem of slower working medium filling speed of the carbon dioxide energy storage system in the prior art, the embodiment of the invention provides a working medium filling and recycling assembly and a working medium filling and recycling method of the carbon dioxide energy storage system, which can realize rapid filling and recycling of liquid carbon dioxide, save construction period and reduce project construction cost. The working medium filling and recycling assembly of the carbon dioxide energy storage system comprises a liquid storage unit and a pressure balancing unit, wherein the liquid storage unit is used for storing liquid carbon dioxide and gaseous carbon dioxide, the liquid storage unit is provided with a liquid phase interface, the top of the liquid storage unit is provided with a first gaseous phase interface, the liquid storage unit is used for receiving the liquid carbon dioxide filled from a carbon dioxide tank car in a filling stage through the liquid phase interface or outputting the liquid carbon dioxide to the carbon dioxide tank car in a recycling stage through the liquid phase interface, the pressure balancing unit comprises a pressure regulating device and a gaseous phase balancing branch pipe, the pressure regulating device is respectively connected with the liquid phase interface and the first gaseous phase interface, the pressure regulating device is used for carrying out gas-liquid conversion on the carbon dioxide in the liquid storage unit in the filling stage so that the pressure in the liquid storage unit reaches the design pressure, the first gaseous phase interface is connected with the first end of the gaseous phase balancing branch pipe, the second end of the gaseous phase balancing branch pipe is used for connecting the carbon dioxide tank car, and the gaseous carbon dioxide can flow between the liquid storage unit and the carbon dioxide tank car through the gaseous phase balancing branch pipe to balance the pressure between the liquid storage unit and the carbon dioxide tank car. In some embodiments, the pressure regulating device comprises a liquefaction part, a working medium outlet of the liquefaction part is connected with the liquid phase interface, a working medium side of the liquefaction part is connected with the first gas phase interface, and the liquefaction part is used for converting the gaseous carbon dioxide into the liquid carbon dioxide and outputting the liquid carbon dioxide to the liquid storage unit so as to reduce the pressure in the liquid storage unit to a design pressure in the filling stage. In some embodiments, the pressure balancing unit further comprises a first balancing pipe co