Air dehumidification using various TEG based nano solvents in hollow fiber membrane contactors

Abstract

In this study, tri-ethylene glycol (TEG) based nanofluids of carbon nanotubes (CNT), silica (SiO2) and aluminum oxide (Al2O3) in different weight percents of 0.01 and 0.05 wt% were employed to improve the properties of TEG for water vapor absorption in a hollow fiber membrane contactor (HFMC). To do so, the impact of various operational parameters including nanofluid type, nanoparticles (NPs) concentration, liquid and gas flow rate on water vapor separation were elucidated. According to obtained results, CNT nanofluid was more capable on water vapor absorption toward SiO2 and Al2O3, so that the injection of CNT nanofluid led to water vapor absorption enhancement up to 10.8 % as compared to TEG solution alone. The results also indicated that the gas flow rate has an inverse relationship with the amount of water vapor absorption efficiency, whereas increasing the liquid flow rate has no tangible effect on absorption efficiency, which is because of the very high solubility of water vapor in TEG. Ultimately, dynamic light scattering (DLS) analysis was carried out to evaluate the stability of nanofluids and size distribution of nanostructures in the base fluid.