RECENT Developments IN THE Robust Fabrication of Thin-film Nanocomposite Membranes for the Environmental Care

다국어 초록 (Multilingual Abstract)

Power generation in recent decades has been carried out by coal-fired power plants, which use coal to generate electricity. Burning of coal is generated large quantities of flue gas which contains N₂, O₂, CO₂, nitrogen oxides (NOx), sulfur oxides (SOx), fly ash, and water vapor. Lots of water vapor discharged from stacks and cooling towers of factories into the atmosphere is a serious crisis, as global warming is growing and more consumption of the limited water resources. In addition, white flume produced by condensing water vapor from flue gas becomes a cause of visual pollution. In the presence of a large amount of water vapor in the stack, condensation can readily occur, resulting in corrosion. For these reasons, water vapor is preferably removed from flue gas. On the other hand, volatile organic compounds (VOCs) are a generic term for liquid or gaseous hydrocarbon compounds that are easily evaporated into the atmosphere due to their high vapor pressure. These VOCs are emitted from public power generation facilities, district heating facilities, petroleum refining facilities, private power generation facilities, organic chemical product manufacturing industries, and other combustible or noncombustible sources, resulting in leading to compromised air quality. Therefore, it is necessary to create a clean environment by removing not only water vapor but also VOCs. Many technologies are used to remove water vapor and VOCs, but they have their own characteristics. For example, heat treatment technology is more suitable for high VOC concentrations (preferred for large and medium-sized workplace), adsorption treatment technology is more suitable for low VOC concentrations (preferred for small and medium-sized workplace). Membrane-based technology does not require thermal regeneration and phase change, and thus consumes less energy. Furthermore, it is compact, energy-efficient, easy to scale, low initial investment and simple to use and maintain. Therefore, membrane-based technology can be an attractive alternative that is used as a hybrid with existing technologies or to replace existing technologies to remove water vapor and VOCs. In this study, we propose a method of removing water vapor and VOCs together by using polymeric hollow fiber membranes. The polymeric membranes are coated with hydrophilic materials and hydrophobic materials to remove water vapor and VOCs, respectively. In order to further improve their performance, thin film nanocomposite (TFN) membranes with nanoparticles are also developed and tested the separation performance for environmental care.