The Experimental Study And Numerical Simulation Of CO₂Adsorbent-Macropore CaO

The negative effects of CO2to the global environment directly relate to related to the survival of human society, and the greenhouse effect is no longer a problem in the field of climate and the global environment. How to reduce CO2in the exhaust was becoming as a current and important research subject. CaO is extensive, low preparation cost, short reaction time, good adsorption and recyclable. So CaO is a good absorbent and has been paied close attention. But adsorption ability of common lime adsorbents are limited, and their pores were easily blocked in the process of carbonization. Evenmore, common lime adsorbents were occured agglomeration in the process of calcinations. How to improve the adsorption ability of lime adsorbents is becoming a research hot-spot.Adsorbent-macroporous CaO were prepared in the laboratory by experiment method to solve the problem of hole blockage in the carbonization process and improve adsorption efficiency of the CO2. Properties of macroporous lime adsorbents are verified by means of experiments and simulations. And the relationship between osmotic pressure drop and various parameters was also discussed, but the simulation results were reliable.Pore structure of the adsorbent-macroporous CaO was studied and found that the pore structure inside the adsorbents was complex and had the fractal characteristics and randomness. Adsorption process of CO2was difficult to accurately calculate through various adsorption model established by predecessors. So this paper presents a fractal model to simulate adsorption process of CO2with macroporous lime adsorbents. The results showed that the calculation results coincided well with the experimental results, but the adsorption model also needed further modification and validation. And Fluent6.3was used to study the flow characteristics of fluid in the fractal pore model, to provide the reference data of fluid flow in real lime adsorbents channels.The gas-solid bubbling fluidized bed was used to adsorb CO2, the adsorbents was adsorbent-macroporous CaO. The research method is a combination of experiment and simulation. Fluidization of different particles and different gas in fluent software was different, and the best operation conditions were different. Therefore, cold simulation of particles and gases firstly was conducted, and obtained the optimum operating conditions. Under the best fluidization condition, the effects of gas concentration and reaction temperature on conversion rate of adsorbent-macroporous CaO were studied.