Performance Study On Carbon Capture Technology Based On Gas-solid Phase Separation

With the rapid development of human society,excessive emissions of greenhouse gases such as carbon dioxide have triggered a series of climate problems such as global warming.As a transitional carbon emission reduction technology,CO₂capture technology embodied chemical reaction can reduce the emission reduction of large-scale centralized emission sources such as power plants and cement plants,and alleviate the harm caused by the greenhouse effect.However,existed traditional carbon capture technology demonstrated many drawbacks.Thus,carbon capture technology based on gas-solid separation phase change mechanism as a potential alternative technology,has advantages in process design,with a possible extended application,is emerging from the ocean of technological values In this paper,the content is organized as follow:In this work,the limit of energy efficiency of carbon capture technology was researched based on the finite-capacity and infinite-capacity carbon pump models,which was also calculated in a case study.The results indicate that the separation model and the finite-capacity chemical pump model shows no difference in the view of thermodynamic ideal approach,which with totally different application background though.And the separation model was also proved less ideal than the infinite-capacity chemical pump model.The theoretical energy of the separation model and the finite-capacity chemical pump model is 0.148 MJ/kg in a typical working condition with CO₂ concentration is 15%.Then,a mathematical model is established to get the physical property data of the gas-solid phase change process.It is mainly divided into two parts.The first part is based on the fugacity conservation to predict the gas-liquid equilibrium and gas-solid phase equilibrium of the CO₂-containing mixture.The second part is based on Gibbs free energy to calculate the enthalpy entropy of solid CO₂.The analysis model solves the data and finds when the CO₂ concentration is 49.1%at a system pressure of 1MPa,it is no longer possible to capture by gas-liquid phase separation.Finally,based on the arrangement of thermal processes and the“process engineering”method in chemical industry,the specific composition of gas-solid phase separation carbon capture system was designed.In this paper,a conventional gas-solid phase separation carbon capture system is designed for performance studying,and according to the conclusion,the system is further optimized.The simulation results show that the energy consumption of the conventional system is 2.25 MJ/kg in a typical working condition with CO₂ concentration is 15%.Subsequently,the heat recovery optimization design of the carbon capture system was carried out,and the flue gas circulation and the refrigeration cycle were heat-coupled to achieve the purpose of energy saving.The simulation results show that the energy consumption of the gas-solid phase separation system is 0.963 MJ/kg in a typical working condition with CO₂ concentration is 15%.