Abstract:

Membranes are promising candidates for the separation of carbon dioxide from the flue gas of fossil fuel power plants. The stability of the membrane systems directly restraints its extensive application. This study analyzes the characteristics of membranes，such as pore diameter distribution and porosity，which could affect separation efficiency and stability of the system. Under real conditions，after long-term exposure in flue gas，the impurities could change the performance of membranes. The reduction of gas flux was mainly caused by the deposition of ash particles and gypsum. Water vapor could condense on the surface of membranes or in the pores of membranes through capillary condensation. The presence of sulfur dioxide would decrease the carbon dioxide captured by membranes in the process of competitive adsorption，which resulted in a change of gas flux. All these factors would negatively impact the performance of membranes and affect the application of membrane systems.

摘要：

膜法捕集CO₂系统运行的稳定性直接制约其大规模运用，本文总结分析了其稳定性一方面受到膜自身特点，如孔径分布、孔隙率等的影响；另一方面燃煤烟气杂质对膜系统的作用也是限制其发展的要素所在，如细颗粒物会吸附沉积在膜表面或膜孔内部、水蒸气易冷凝于膜表面或在孔径内形成毛细管冷凝现象、SO₂会与CO₂形成竞争吸附，这些因素都会引起气体通量的变化，从而改变膜捕集系统的性能。