Research Of Using Composite Membrane To Capture Water Vapor In Flue Gas And Permeation Mechanism

Coal combustion produce large amounts of flue gas, content of flue gas water vapor is about 10%, the presence of smoke water results in not only waste of water resources, but also a greater heat losses and environmental pollution, therefore the recovery of flue gas water vapor provide a new water-saving idea for the thermal power plants. Gas dehumidification process by membrane technology is a newly developed dehumidification technology. Dehumidification by membrane technology possesses many advantages^ such as low investment, low energy consumption, convenient usage and flexible operation etc., having a broad prospect for development. Study research of using composite membrane to capture water vapor in flue gas and permeation mechanism, include in mass transfer resistance of flue gas water vapor in composite membrane, preparation hollow fiber composite membrane, and bench for capturing water vapor.Firstly, using Fluent to build mass transfer resistance model for flue gas water vapor in composite membrane, to simulate permeation process, compare resistance under different conditions such as pressure, velocity, separation factor, flux and flue gas composition. Then select the composite membrane materials for thermal power plant separating flue gas water vapor, through the full investigation and comparison penetrates separation parameters of the different membrane material, make SPEEK / PES hollow fiber composite membrane, set up the water recovery system bench, design the flue stack size according to the actual size and different layout scheme membrane module. And use the system to study the effect of different factors on the flue gas water mass transfer coefficient and separation factor. Finally, using Fluent to simulate the impact of different membrane modules arranged programs within the flue on temperature, velocity and pressure, compares the theory and analog changes of flue gas temperature, velocity and pressure, determines the optimal arrangement, and provides the basis for optimization to select operating parameters of the experiment and the membrane structure.