2019-07-23|

Prof. Vivien Lin LU from Hong Kong Polytechnic University gave a talk entitled ‘”Enhancing the mass transfer of falling film dehumidifier by plate surface treatment and liquid desiccant modifications’ at the Faculty of Science and Technology on 11 July, 2019. At the seminar, Prof. Lu shared her latest research results in the fields of dehumidification performance of falling film dehumidifier. Amongst different dehumidification technologies, the plate-liquid desiccant type is promising. However, normally, the falling film does not cover the whole plate with film contraction and breakdown, thereby immediately losing some absorption capability, and the liquid droplet carryover by the process air will cause the corrosion of ventilation system. Therefore, this work aims to improve the moisture removal efficiency of this type of dehumidification process by plate surface modification and liquid desiccant modification. Regarding plate surface treatment, an extremely thin TiO2 (titanium oxide) bilayer with a protective layer for coating the plates was successfully developed which provides the plates with super-hydrophilic properties causing the falling desiccant film to entirely cover the plates with less droplet carryover. Regarding liquid desiccant modification, a new kind of additive (polyvinyl pyrrolidone (PVP-K30)), a novel LiCl/H2O-MWNTs nanofluid and a new mixed liquid desiccant solution were successfully fabricated and introduced into the technology respectively which all can largely enhance the moisture removal ability.