Supercritical carbon dioxide generator set working medium storage system

Abstract

The utility model relates to a working medium storage system of a supercritical carbon dioxide generator set, which is characterized in that an oil-water separator is additionally arranged at a compressed air source inlet of a liquid booster pump; a heating device is arranged around the liquid booster pump; a check valve is arranged between the working medium inlet and the working medium outlet of the liquid booster pump; a temperature measuring point is additionally arranged at a liquid booster pump working medium inlet; a pressure measuring point is additionally arranged at a liquid booster pump working medium outlet. On the basis of the original working medium storage system and process flow of the supercritical carbon dioxide generator set, the oil-water separator, the auxiliary heater, the check valve, the temperature sensor and the like are added; the problems that a liquid booster pump in a supercritical carbon dioxide working medium storage system works continuously for a long time and a pipeline is frosted and frozen can be effectively solved, and therefore carbon dioxide with the needed pressure is supplied to a unit.

Description

Technical Field

[0001] The utility model relates to a marine supercritical carbon dioxide Brayton cycle power generation system, in particular to a working medium storage system for a supercritical carbon dioxide generator set. Background Art

[0002] At present, the working medium storage system of a supercritical carbon dioxide generator set is composed of a cryogenic liquid storage tank, a liquid booster pump, a vaporizer, valves and instruments, as Figure 1 shown. The specific working process: The working medium is filled into the cryogenic liquid storage tank by a liquid carbon dioxide tanker, and then flows out from the liquid outlet of the storage tank and is pressurized by the liquid booster pump, and then enters the vaporizer for heating. A small part of the vaporized liquid carbon dioxide returns to the storage tank through the gas-liquid balance loop to maintain the pressure balance of the storage tank. Most of the heated gaseous carbon dioxide enters the supercritical carbon dioxide generator set system for the unit to use.

[0003] The carbon dioxide filled into the cryogenic liquid storage tank by the tanker has a temperature of -35°C and a pressure of 2.2 MPa. The designed inlet and outlet temperatures of the carbon dioxide in the vaporizer are -40°C and 80°C respectively, and the vaporization amount is 700 kg / h. The pressure ratio of the liquid carbon dioxide booster pump is 28:1, the maximum outlet pressure is 22.4 MPa, the maximum outlet flow rate is 13.7 L / min, the driving gas source pressure is 0.6 - 0.8 MPa, the material is stainless steel, and it is mainly composed of a box body, a gas-liquid booster pump and a pipeline platform, including a pressure gauge, a high-pressure gauge, a pressure regulating valve, a low-pressure switch and a high-pressure switch. The compressed air system includes an air compressor, a gas storage tank and a refrigerated compressed air dryer.

[0004] During the operation of the carbon dioxide working medium storage system, as time goes by, the boosting effect of the liquid booster pump weakens, and it makes a "panting" sound. There is frosting at the silencer. After about 1 to 2 hours, the liquid booster pump stops working, and the frosting at the silencer is serious.

[0005] Through the analysis of the technical parameters of the liquid booster pump and the physical properties of carbon dioxide, it is preliminarily judged that the compressed air of the driving gas source of the liquid booster pump contains moisture, which exchanges heat with the -35°C liquid carbon dioxide, resulting in the pipeline being frozen, and the liquid booster pump cannot work normally, affecting the normal operation of the supercritical carbon dioxide generator set. By consulting the physical properties of liquid carbon dioxide, it is found that it instantaneously vaporizes under high pressure conditions. Therefore, during the use of the liquid booster pump, it will absorb a large amount of heat, resulting in a decrease in the surrounding temperature. At the same time, due to the low boiling point of liquid carbon dioxide, it can vaporize and absorb heat even at normal temperature and pressure, condensing the surrounding moisture into frost or ice, causing the booster pump to freeze and unable to work.

[0006] Therefore, it is necessary to improve the existing working medium storage system and process flow of the supercritical carbon dioxide generator set. Summary of the Invention

[0007] In view of the above problems, the present utility model proposes a working medium storage system applicable to a supercritical carbon dioxide power generation unit. Considering the working characteristics of the liquid carbon dioxide booster pump and the specific natural environment, the existing process flow is improved to ensure that the working medium storage system can operate continuously and reliably, thereby ensuring the normal power generation of the supercritical carbon dioxide power generation unit.

[0008] To achieve the above object, the technical solution of the present utility model is a working medium storage system for a supercritical carbon dioxide power generation unit, including:

[0009] 1) An oil-water separator is added at the compressed air source inlet of the liquid booster pump;

[0010] 2) A heating device is arranged around the liquid booster pump;

[0011] 3) A check valve is arranged between the working medium inlet and outlet of the liquid booster pump;

[0012] 4) A temperature measuring point is added at the working medium inlet of the liquid booster pump;

[0013] 5) A pressure measuring point is added at the working medium outlet of the liquid booster pump.

[0014] Furthermore, the temperature measuring point added at the working medium inlet of the liquid booster pump is used to monitor the inlet temperature, adjust the temperature of the liquid carbon dioxide, keep the temperature within the required range, and leave a certain margin.

[0015] Furthermore, the pressure measuring point added at the working medium outlet of the liquid booster pump is used to control the output pressure of the working medium at the outlet of the liquid booster pump and reduce the influence of the vaporization of the liquid carbon dioxide.

[0016] Furthermore, the oil-water separator added at the driving air source inlet of the liquid booster pump is used to remove the moisture in the compressed air source and reduce the influence of the endothermic cooling caused by the vaporization of the liquid carbon dioxide.

[0017] Furthermore, the heating device arranged around the liquid booster pump is used to heat and increase the ambient temperature around the liquid booster pump.

[0018] The beneficial effects of the present utility model are:

[0019] The system and process method proposed by the present utility model add devices such as an oil-water separator, an auxiliary heater, a check valve, and a temperature sensor on the basis of the original working medium storage system and process flow of the supercritical carbon dioxide power generation unit, and can effectively solve the problems of continuous long-term operation of the liquid booster pump and pipeline frosting and freezing in the supercritical carbon dioxide working medium storage system, thereby supplying carbon dioxide with the required pressure for the unit.

[0020] Meanwhile, the present utility model has important guiding significance for the process design, development and test of the entire supercritical carbon dioxide power generation unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is the existing working medium storage system and process flow diagram of the supercritical carbon dioxide power generation unit;

[0022] Figure 2 is the working medium storage system and process flow diagram of the supercritical carbon dioxide power generation unit of the present utility model. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0023] The present utility model will be further described below in conjunction with the drawings and embodiments.

[0024] As Figure 2 shown, a working medium storage system of a supercritical carbon dioxide power generation unit proposed in an embodiment of the present utility model includes:

[0025] 1) At the compressed air source inlet of the liquid booster pump 1, an oil-water separator 2 is added to remove as much moisture as possible from the compressed air;

[0026] 2) Around the liquid booster pump 1, a heating device 3 is provided to increase the ambient temperature around it and reduce the influence of the endothermic vaporization of liquid carbon dioxide as much as possible;

[0027] 3) A check valve 4 is provided between the working medium inlet and outlet of the liquid booster pump 1 to prevent the working medium in the pipeline from flowing back into the booster pump body;

[0028] 4) A temperature measuring point is added to the working medium inlet of the liquid booster pump 1 to adjust the temperature of the liquid carbon dioxide and keep it within a reasonable range;

[0029] 5) A pressure measuring point is added to the working medium outlet of the liquid booster pump 1 to control its output pressure and reduce the influence of the vaporization of liquid carbon dioxide.

[0030] A process flow method provided by an embodiment of the present utility model, as Figure 2 shown, adopts a working medium storage system of a supercritical carbon dioxide power generation unit of the present utility model. According to the improved process flow diagram above, first, an oil-water separator 2 is added at the driving gas source inlet of the liquid booster pump 1 to remove the moisture in the compressed air source and reduce the influence of the endothermic vaporization of liquid carbon dioxide; then a heating device 3 is used to increase the ambient temperature around the liquid booster pump, and at the same time, a check valve 4 is provided at the outlet of the liquid booster pump 1 to prevent the backflow of the working medium. Finally, the temperature at the working medium inlet and the pressure at the outlet of the liquid booster pump 1 are monitored and controlled within a reasonable range, leaving a certain margin.

Claims

1. A supercritical carbon dioxide generator working fluid storage system, characterized in that: include: 1) Install an oil-water separator at the compressed air source inlet of the liquid booster pump; 2) A heating device is provided around the liquid booster pump; 3) A check valve is provided between the inlet and outlet of the liquid booster pump; 4) Add a temperature measuring point at the working fluid inlet of the liquid booster pump; 5) Add a pressure measuring point at the outlet of the liquid booster pump.

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