Supercritical Brayton cycle bypass impurity removal system and method

Abstract

Disclosed are a supercritical Brayton cycle bypass impurity removal system and method. The supercritical Brayton cycle bypass impurity removal system comprises a heat source, a supercritical Brayton cycle system, an impurity removal bypass and a CO2 compressor intermediate-stage shunting and throttling refrigeration system which communicate in sequence. The impurity removal system serves a supercritical CO2 power generation system to eliminate gas impurities in the system, improve the purity of CO2 in the system and ensure the performance of the system. According to the supercritical Brayton cycle bypass impurity removal system, compressor intermediate-stage extracted gas is used for self-cooling to form a low-temperature cooling working medium, then the low-temperature cooling working medium is used for cooling a low-pressure CO2 working medium in the bypass to make the low-pressure CO2 become liquid, the liquid CO2 in the bypass shunts and removes impurity gases such as O2 and N2 mixed into the system in a separator, and the impurity removal bypass does not need to operate all the time and only needs to operate when the impurity content of the system is detected to be too high. The supercritical Brayton cycle bypass impurity removal system utilizes equipment of the CO2 system to the greatest extent, it is not needed to add complex chemical systems or chemical agents, the investment and operating cost of the impurity removal process are reduced, and the purity of the working medium of the supercritical CO2 power generation system is maintained.

Description

technical field [0001] The invention relates to the technical field of power generation systems, in particular to a supercritical Brayton cycle bypass impurity removal system and method. Background technique [0002] Under the background of energy shortage and environmental crisis, people pay more and more attention to improving energy efficiency. Among the many thermodynamic cycles, the supercritical Brayton cycle is the most advantageous cycle form. New supercritical working fluids (carbon dioxide, helium and nitrous oxide, etc.) have inherent advantages such as high energy density, high heat transfer efficiency, and simple system, which can greatly improve thermal power conversion efficiency, reduce equipment volume, and have high economic efficiency. sex. [0003] However, this type of cycle also has an obvious technical difficulty. The supercritical carbon dioxide Brayton cycle uses carbon dioxide as the work instead of water. In the cycle system, the use of carbon di...

AI Technical Summary

Problems solved by technology

However, because CO2 in the system is in a supercritical state and has no phase transition, it is difficult to separate from N2 and O2. It is more complicated to remove N2 and O2 by chemical reaction, and it is not easy to ensure that other chemical elements are not mixed, and N2 It is an inert gas, and it is not easy to separate by chemical methods

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