Study On Characteristics Of Heat And Mass Transfer In Adsorbing And Capturing Carbon Dioxide

With the rapid development of the global economy, the demand of fossil fuel has rapidly increased. Therefore, the quantity of carbon dioxide emissions is incrementing year by year. More and more people have regarded the global change. Greenhouse effect cased by emissions of greenhouse gases such as carbon dioxide. The amount of carbon dioxide emission from fossil fuels accounts for 80 percent of all the emission caused by human activity, and the amount of carbon dioxide from power plants is 30 percent. So the removal of carbon dioxide from flue gas of power plants is the sticking point on greenhouse effect mitigation.The study on adsorbing and capturing carbon dioxide in flue gas in China is still in its infancy stage. On this basis, the method of capturing carbon dioxide by pressure swing adsorption and power swing desorption is presented in this paper. Activated carbon fiber as adsorbent for capturing carbon dioxide in flue gas is presented through analysing the performance of several adsorption materials. Electrical conductivity of activated carbon fiber was measured. Under the power-on condition, the quantity of activated carbon fiber desorbing carbon dioxide and the temperature distribution of desorption tank is measured during the experiment, and analyzed the thermal stability of it. Through the analysis of experimental data, adsorption isotherm equation of carbon dioxide and nitrogen was derived. On this based, it was established that the system of separating carbon dioxide from flue gas.According to the theory of fluid mechanics, thermodynamics and heat transfer, it is established that the dynamic model of tower during adsorption process and desorption process. These governing equations are discrete using finite volume method and solved using the algorithms of SIMPLE. The program is designed using MATLAB in order to get adsorption properties and temperature field in diffierent pressure boost times and desorption properties and temperature field of carbon dioxide in different power voltages.According to the simulation system of adsorbing and capturing carbon dioxide from flue gas, factors of influencing adsorption and desorption properties of carbon dioxide. The influence factors of thermal conductivity, flue gas flow of inlet, power-ontime and volt are analysised, and calculate the temperature filed and adsorption capacity and desorption capacity. It provide a reference for researching equipment of capturing carbon dioxide by pressure swing adsorption and power swing desorption.