活性炭捕集燃煤烟气中二氧化碳的模拟分析

Dynamical adsorption of CO ₂ in flue gas by fixed-bed was simulated by Aspen Adsorption to investigate the suitable mathematical model for CO ₂ adsorption by activated carbon and the solid adsorption process for regenerating CO ₂ using steam blowing. Comparison between simulative and experimental breakthrough curves showed that the simulation data with ideal adsorption solution-linear diver force (IAS-LDF) model was more coincident with experimental data than results of models using pure component adsorption or Particle MB model. A complete temperature swing adsorption model was established, and the fixed-bed was heated and cooled respectively by high-temperature steam and adsorbed flue gas. The effects of purge temperature, adsorption / desorption time on CO ₂ capture rate, product purity and energy consumption were analyzed. The results showed that the increase of purge temperature enhanced the capture rate significantly and raised energy consumption slightly, but had few effects on the product purity. When the purge temperature increased from 100 °C to 200 °C with the adsorption / desorption time of 2~4 min, the capture rate increased by 11.1%, the energy consumption increased by 13.9%, and the product purity increased by 1.7%. The increase of adsorption / desorption time greatly improved the product purity, but reduced the capture rate and increased the energy consumption obviously. When the adsorption / desorption time increased from 2 min to 4 min with the purge temperature of 100~200 °C, the product purity increased by 13.6%, the capture rate of CO ₂ decreased by 4.8%, and the energy consumption increased by 43.1%.