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2022

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State of the art of Supercritical carbon dioxide solar thermal power generation

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The Supercritical carbon dioxide cycle power generation system is an advanced thermal power conversion technology. It uses Supercritical carbon dioxide as the working medium to work in a closed thermal cycle. When the heat source temperature exceeds 500, the Supercritical carbon dioxide cycle is suitable for the heat source temperature. It can use 400-700 heat sources, and the cycle efficiency is as high as 40% -50%. With a compact structure, it can achieve 10-20MWe modular design. Then, let's take a look at the State of the art of Supercritical carbon dioxide solar thermal power generation.

Supercritical carbon dioxide cycle power generation system is an advanced thermal power conversion technology, using supercritical carbon dioxide as the working medium, working in a closed thermal cycle, when the heat source temperature exceeds 500, the supercritical carbon dioxide cycle is suitable for the heat source temperature, 400-700 heat sources can be used, the cycle efficiency is as high as 40%-50%, and the structure is compact, and the modular design of 10-20MWe can be realized. So, let's take a look at the development status of supercritical carbon dioxide solar thermal power generation technology.

Supercritical carbon dioxide

Started a large number of system integration and optimization research, mainly for high-temperature reactor power generation; However, under the technical conditions of the time, many difficult problems could not be solved, and the development was slow after that. At the beginning of this century, fourth-generation nuclear reactors, characterized by high temperatures, received widespread attention, and research on power generation gradually attracted attention. The tower solar supercritical CO2 power generation system formed by combining supercritical carbon dioxide power generation technology and tower solar heat collection technology has the potential to greatly improve energy efficiency and reduce power generation costs, promotes the development of supercritical CO2, and begins to enter the stage of technology development and application.

Research progress and mechanism of system integration

1. Research progress of system integration

In the 60s and 70s, based on the simple recuperative supercritical carbon dioxide cycle, in-depth system integration research was carried out, according to whether the supercritical fluid was shunted or not, the supercritical fluid was divided into whether there was a shunt and whether there was a shunt, reducing the circulating heat dissipation temperature, increasing the heat absorption temperature of the reheat cycle, reducing the irreversible loss of intermediate recuperation or recompression reheating process, segmented expansion, precompression, and parallel turbine methods to improve system energy consumption.

2. Energy efficiency improvement mechanism of recompression supercritical carbon dioxide

Improve the efficiency of cyclic power generation by changing physical properties close to the critical point

The reason for the high thermal power conversion efficiency of supercritical CO2 cycle is directly related to the strong non-ideality of CO0 engineering near the critical point. Change in compression factor and specific heat near the critical point. The compression factor of supercritical CO2 near the critical point is much higher than that of atmospheric pressure air (about 0) between 5.1-30.1, the specific heat near the critical point is above <>kJ/kgK, the compression factor of normal temperature and atmospheric pressure air specific heat (much higher than <>kJ/kgK) is reduced, the energy consumption of the compression process is reduced, and under the same heat source conditions, the working temperature range of the supercritical carbon dioxide cycle becomes larger, and the efficiency is greatly improved.

The use of recompression process to improve the efficiency of cyclic power generation recuperation process is one of the important processes in supercritical carbon dioxide, the heat transfer process must have heat transfer temperature difference, the larger the heat transfer temperature difference, the stronger the irreversibility of the heat transfer process, the lower the thermal efficiency of the system. The difference between the recuperation process T-Q of the simple recuperation cycle of supercritical carbon dioxide and the recompression cycle indicates the magnitude of the heat transfer temperature difference. Under the same condition of small heat transfer temperature difference, the recompression cycle slightly increases the heat transfer in the reheat recuperation process, but the heat transfer temperature difference in the reheat process is greatly reduced, and the recompression technology greatly reduces the irreversible loss of the reheat process, and the power generation efficiency of the recompression cycle is increased by nearly 10 percentage points compared with the pure reheat cycle.

The above introduction is the development status of supercritical carbon dioxide solar thermal power generation technology, if you need to know more, you can contact us at any time! Our company has many years of experience and is always looking forward to your joining.

 

NANTONG WISDOM SCFE

The Company has committed to the field of supercritical fluid extraction equipment for 30 years.